Chapter IV

Microbiology's Moment, 1945-1955

A. Introduction -- The "Spectacular Rise" of Microbiology

On May 13, 1949, C.B. van Niel delivered a lecture dedicated to his mentor A.J. Kluyver, professor at the Laboratory for Microbiology in Delft, the Netherlands. "General microbiology is now a rapidly expanding science," proclaimed van Niel to the Society of American Bacteriologists, assembled for its annual meeting, "and I firmly believe that it is an easily defensible thesis to propose that its spectacular rise is due in large part to the Delft School."⁽¹⁾ Van Niel went on to recount with delight the central importance of microorganisms in recent research in biochemistry and genetics.

Van Niel assessed the dynamic state of general microbiology accurately. Between 1945 and 1955, general microbiology enjoyed a distinct period of expansion. It increased in status, attracted new practitioners, and achieved a new level of institutional security.

Several historical accounts identify the period from about 1940 to 1965 as a "molecular" or "biological revolution" because it produced an extraordinary number of studies associated with the foundation of molecular biology.⁽²⁾ To a considerable extent, this assessment derives from retrospective accounts written by molecular biologists in the 1960's and 1970's or from studies by historians relying on the same sources and/or narrative order. Historian Pnina Abir-Am has given the most incisive (and acerbic) analysis of accounts she has called "second-order legitimations."⁽³⁾ Her work implicitly raises important questions: What significant events, institutions, and practitioners have been excluded from the accounts she has analyzed, and why?

From the viewpoint of many researchers in the 1940's and 1950's, this period might easily have been identified as a "microbial" or "microbiological revolution." Microbiology enjoyed a period of high prestige and rapid expansion before "molecular biology" existed as either a professional identity or widely used label for research.⁽⁴⁾ A significant body of work, later claimed as foundational for molecular biology, was initially carried out under the disciplinary identity microbiology.

Like scientists in many fields, microbiologists enjoyed the benefits of the general postwar expansion in research. Having proved their worth in dramatic terms during the war, especially through antibiotics research, microbiologists were well-situated to take advantage of the new opportunities for patronage and institutional expansion that developed in the 1940's and 1950's. As Rutgers microbiologist Selman Waksman had anticipated, World War II put microbiology on the map. The urgency of wartime research had drawn a number of investigators trained in other fields to work on bacteria and other microorganisms.

Perhaps the most important stimulus to the expansion of microbiology after the war was the formation of a new research specialty, microbial genetics. In the 1940's and 1950's, researchers in large numbers turned to microorganisms to investigate problems in physiological or biochemical genetics. Bacteria, viruses, yeast, and the bread mold Neurospora proved to be especially useful organisms for experimental study of genetics. Several lines of investigation on microbial heredity consolidated to make this field a rapidly moving research front. Research on microorganisms was crucial to the formulation of the one gene/one enzyme principle and the first important models of the regulation of gene expression, advanced in the late 1950's. Bacterial and phage genetics became dynamic research areas in the 1940's and 1950's. Viewed retrospectively, much of this research has been perceived as constitutive of molecular biology. Previous scholarship has emphasized the connections of this research to genetics or biochemistry. From the 1940's until about 1955, however, microbial genetics constituted a distinct research specialty that was as closely linked to microbiology as to genetics. In this chapter, I give evidence of significant social, technical, and institutional connections between microbiology, especially general microbiology, and a substantial body of research later incorporated into the canon of molecular biology.

Van Niel construed the explosion of research on microorganisms as evidence of the success of his project to establish general microbiology as a dynamic and rigorous experimental science of life. Van Niel simply assumed that microbial genetics represented an interesting and valuable sub-field of general microbiology. While van Niel appreciated the increasing importance of microbial genetics, he did not take up this new direction of research. He and his circle of students and colleagues continued to investigate the biochemistry, physiology, and morphology of microorganisms in broad biological terms. The transformation of matter and energy in cellular metabolism continued to be a strong theme. At the University of California, Berkeley, van Niel's former students Roger Stanier and Michael Doudoroff continued teaching and research in accordance with van Niel's conception of general microbiology. At times, they carried out research that bordered on microbial genetics. Nonetheless, they remained proponents of a broadly biological and physiological approach to microbiology.

The new emphasis on microorganisms for experimental research made van Niel's expertise in microbiology important in a new way. Postdoctoral fellows, students, and senior investigators from around the world flocked to his laboratory to learn how to experiment with microorganisms. Van Niel's summer course in microbiology became a key location for the transmission of the basic craft, concepts, and substantive content of microbiology. Elite researchers from a variety of backgrounds competed for admission. Van Niel's course played a special role in training physical scientists for research in biology.

As in the 1930's, the course served several important purposes. For some students, its principal value was practical; it was the best place in the world to learn the craft of microbiology. A second purpose may be termed "acculturation;" many scientists with medical backgrounds came to the course for van Niel's presentation of microbiology as a general science of life. Some scientists came primarily for social legitimation. As the course became part of the common experience of an elite group of scientists, admission into van Niel's course became a mark of social distinction. Finally, ten weeks in a small laboratory on the Monterey Bay could provide both recreation and renewal. Van Niel's course provided a refuge from the moral complexities of postwar science.

In the 1940's and 1950's, boundaries between microbial genetics, biochemical genetics, and microbiology were unstable and indefinite. Socially and intellectually, microbial genetics could be construed as a part of either microbiology or genetics. Van Niel and his students Doudoroff and Stanier at Berkeley maintained close connections with the leaders of microbial genetics, including Max Delbrück, Salvador Luria, Joshua Lederberg, André Lwoff, and Jacques Monod. Van Niel and Stanier shared a special intellectual sympathy with researchers at the Pasteur Institute in the Department of Microbial Physiology, headed by Lwoff. Stanier spent two sabbaticals there and became a lifelong friend and colleague of Monod.

In the late 1950's, research on bacterial and phage genetics became closely allied to a new research area, the structure and function of macromolecules, in conjunction with the larger reordering of knowledge and practices associated with the emergence of molecular biology. Up to the middle of the 1950's, however, much of this research was understood to be part of microbiology. Van Niel's program to cultivate general microbiology as a dynamic and prestigious general science of life then appeared to have reached the pinnacle of success.

B. Van Niel and the Microbe to Center Stage

At the end of the war, van Niel's most urgent concern was to restore contact with Kluyver. From 1940 to 1944, van Niel had no news from Delft. In October 1944, he learned that Kluyver was still alive, but in what condition or under what circumstances he did not know. As soon as postal communications with the Netherlands were restored, van Niel sent off an anxious inquiry.⁽⁵⁾ Four months later, he received a gratifying reply. Kluyver had survived. Like others in Holland, however, he had nearly starved to death during the winter of 1944. Students who had refused to declare loyalty to the Nazis had been deported from the Delft laboratory. Most of the laboratory's equipment and instruments had been destroyed or expropriated. It had been impossible to conduct any research at the Delft laboratory for many months. In the aftermath of the war, Kluyver simply wanted to rebuild his research programs as rapidly as possible.⁽⁶⁾ American and Canadian colleagues offered various kinds of assistance. Horace Barker, for example, organized a project to send reprints to Kluyver to help him catch up on the important research in microbiology that had occurred during the war.⁽⁷⁾ Gifts of tobacco and chocolate were also greatly appreciated.⁽⁸⁾

After the war, van Niel assumed the mantle of the world's leading exponent of general microbiology. He won numerous prestigious honors and received attractive offers from important institutions. In 1945, van Niel was elected to the National Academy of Science of the United States. That year, the President of Yale University asked van Niel to advise at a conference on a proposed microbiology department there.⁽⁹⁾ Van Niel wrote to the president of Stanford that he had accepted the invitation, "since there are few things I have so warmly at heart as the sound development of the sciences of general and applied microbiology." An offer of an endowed professorship at Yale soon followed.⁽¹⁰⁾ Princeton University, too, attempted to convince van Niel to join its faculty. Van Niel accepted an honorary doctorate, but not a professorship, from Princeton.⁽¹¹⁾

Van Niel and colleagues acted quickly to restore professional relationships severed by the war. In the fall of 1945, Stanier went to England as a Guggenheim Fellow to work with microbiologist Marjorie Stephenson. Van Niel was delighted to have an emissary in Europe. It went without saying that Stanier, as van Niel's heir apparent, would visit Kluyver and the Laboratory for Microbiology in Delft. Stanier also planned to visit the most prominent microbiologists and biochemists in England. "Give my very best regards to Marjorie [Stephenson]," he wrote to Stanier. "You will also meet Knight, D.D. Woods, Quastel, Krebs," he continued, naming some of the leading European researchers in biochemistry and microbial physiology. Van Niel was also anxious for news of researchers at the Pasteur Institute, especially André Lwoff, whose work on the physiology of protozoa and their nutritional requirements he very much admired.⁽¹²⁾ "His has been some of the most significant work, both experimentally and philosophically since 1930, I feel," he wrote to Stanier.⁽¹³⁾

Doudoroff, too, was pleased that Stanier had won the fellowship and would go to Stephenson's laboratory. "Of all of van Niel's students," Doudoroff wrote to Stanier, "I think you are most likely to be outstanding and to carry on his traditions. (This is not meant as merely pleasantries, but is a firm conviction, based on the knowledge of your work and capabilities). Already you have... a rather enviable reputation which I hear on all sides."⁽¹⁴⁾ Stanier spent half of 1945 in Stephenson's laboratory at Cambridge, where he also began a lifelong friendship with algae specialist Ernst G. Pringsheim.

That microorganisms were moving to center stage in experimental biology became evident in the Cold Spring Harbor symposium of 1946. Organized by Milislav Demerec, director of the Department of Genetics and the Biological Laboratory, it was the first symposium held since the summer of 1941. Its theme was "Heredity and Variation in Microorganisms."

Demerec, a classically trained geneticist, had conducted research on maize and Drosophila at CSH laboratories since 1924. During the World War II, however, he undertook research on the genetics of the penicillin mold. The purpose of the project was to determine if penicillin yields could be increased through genetic mutations in the mold. Ultimately, his group found a mutant that produced penicillin in submerged cultures. At the same time, he began to study penicillin resistance in bacteria, a topic that naturally led to serious considerations of bacterial genetics.⁽¹⁵⁾

The meeting brought together a diverse group of investigators who were working on microorganisms and genetics. Many of the assembled investigators had been isolated from one another during the war. The meeting demonstrated that the genetics of microorganisms was a dynamic research area. It contributed to the intellectual and social formation of a new research specialty, microbial genetics, assembled from diverse projects that had not been seen as closely related before World War II. The meeting provided an excellent opportunity for scientists to collect and review recent research on microorganisms and to discover their common interests and concerns.

Van Niel, a leading authority in general microbiology, attended the meeting along with researchers directly concerned with microbial heredity. From van Niel's point of view, the new research on the genetics of microorganisms provided gratifying evidence of the success and importance of general microbiology. Throughout the 1940's and 1950's, van Niel kept close track of the new research being carried out on microorganisms. He developed cordial relations with the most important researchers working on the newly emerging fields of microbial and viral genetics, including among others Beadle, Tatum, Lederberg, Luria, Delbrück, and especially Lwoff's group at the Pasteur Institute. They communicated frequently through correspondence and scientific meetings with the leaders of the newly emerging fields of microbial and viral genetics.

The research reports given at the meeting illustrated that understanding of microorganisms was in the midst of a major upheaval. Well into the 1930's, bacteria were generally regarded as primitive organisms with a biology in some ways incommensurate with that of so-called higher organisms. Van Niel's work on photosynthesis provided an important counter to that viewpoint, but there was one major barrier his work had done little to overcome, namely the problem of genetics. Bacteria appeared to be more physiologically and genetically flexible than more complex organisms. "Perhaps bacteria may tentatively be regarded as biochemical experimenters; owing to their relatively small size and rapid growth, variations must arise very much more frequently than in more differentiated forms of life," wrote the biochemist and microbiologist Marjory Stephenson in 1930.⁽¹⁶⁾ A dominant view held that bacteria were Lamarckian organisms. The phenomenon known as "bacterial adaptation" provided the most compelling evidence for this viewpoint. Cultures of bacteria that could develop the capacity to metabolize a new sugar source were said to "adapt" to the new medium. Further, most investigators up to the 1940's, including van Niel and Stanier, had concluded that bacteria did not reproduce sexually. Bacteria appeared to reproduce exclusively through simple cell division. Bacteria appeared to be fundamentally different from so-called higher organisms cytologically as well. Viewed by conventional light microscopy, bacteria appeared to lack an organized internal structure. They were sometimes described as mere "bags of enzymes."⁽¹⁷⁾ The status of the bacterial nucleus was dubious as well. Because bacteria reproduced asexually, they seemed not to need one.

In 1943, Luria and Delbrück carried out one of the first important challenges to the Lamarckian viewpoint. They developed a distinctive approach to the study of bacterial heredity that took advantage of recent work on bacteriophage. Luria and Delbrück had observed that a given culture of bacteria would sometimes become resistant to infection by bacteriophage. They set out to determine if the acquisition of this new character was environmentally induced or the result of a random, spontaneous mutation.⁽¹⁸⁾ They employed an innovative statistical method to analyze the appearance of clones of bacteria that were resistant to bacteriophage. They followed the pattern of the appearance of the new character in bacteria in the presence and in the absence of the bacteriophage. Under both conditions, bacteriophage resistance appeared in bacterial cultures randomly. They found no evidence that the presence of phage in the culture environment caused the character of phage resistance to appear. On the basis of these observations, Luria and Delbrück concluded that bacteria were not Lamarckian organisms. Rather, they inferred that spontaneously occurring, random genetic mutation accounted for the acquisition of phage resistance.

The experiments of Luria and Delbrück impressed Stanier, who wrote to Delbrück with his compliments. Delbrück was more interested in the bacteriophage than the bacterium, however, which he tended to regard as a reaction vessel, not the phenomenon of interest. "I am more and more puzzled by the whole phage problem," Delbrück replied to Stanier, "I wish somebody would make a great discovery, like Hadley's cyclostages. Only it should be understandable and true."⁽¹⁹⁾

Retrospectively, the Luria and Delbrück experiment was proclaimed as the beginning of modern bacterial genetics. "The famous proof that bacterial mutations occur marks the beginning of bacterial genetics," wrote molecular biologist Gunther Stent in 1963.⁽²⁰⁾ At the time it was produced, however, its influence was diffuse. It was one piece of experimental work contributing to a revision of conceptions of bacterial heredity. It implied that bacterial variation could be understood in terms of discreet mutations.⁽²¹⁾

At the Cold Spring Harbor meeting of 1946, it became apparent that a major attack on earlier views of microbial genetics was underway. A central question was whether or not bacteria and their viruses, the bacteriophage, contained genes like those in more complex organisms. Delbrück and his colleague A.D. Hershey both reported on the occurrence of mutations in bacterial viruses.⁽²²⁾ The implication was that if bacteriophage had mutations, they must also have genes. If they had genes, they had a biologically important property in common with complex organisms. Similarly, Demerec, Luria, Lwoff, Tatum, and Arthur Shapiro all gave papers giving evidence for bona fide mutations in bacteria. The same logic applied. If bacteria exhibited mutations, then they too might be endowed with genes similar to those in more complex organisms. This work extended the research carried out by Luria and Delbrück in 1943.⁽²³⁾

The CSH meeting also included the group of investigators headed by Oswald Avery at the Rockefeller Institute for Medical Research. Avery and his colleagues had been investigating the phenomenon of the transfer of virulence from heat-killed Pneumococcus to non-virulent living strains.⁽²⁴⁾ Avery's initial interest in the problem was primarily medical. In 1944, Avery's group reported that a substance called desoxyribonucleic acid was the chemical agent of transformation.⁽²⁵⁾ Retrospectively, Avery was charged with undue caution for failing to extrapolate from his work on the transforming principle to a grand claim that desoxyribonucleic acid was the material of which genes were made.⁽²⁶⁾ This assessment fails to take adequate account of the uncertain status of bacterial heredity and bacteria as biological entities in the 1940's. The idea that bacterial heredity was analogous to that of more complex organisms was just beginning to achieve acceptance, as the CSH meeting of 1946 illustrated.

One of the most important papers at this pivotal meeting reported that genetic recombination occurred in bacteria.⁽²⁷⁾ While still at Stanford, Tatum had begun experiments with bacteria that paralleled his important investigations with Beadle on Neurospora. By 1945, Tatum had prepared several nutritional mutants in the bacterium E. coli (strain K12).⁽²⁸⁾ The fact that mutants of this kind could be produced implied that bacteria contained genes analogous to those in more complex organisms. In 1945, Joshua Lederberg, then a medical student working part-time at Columbia with Francis Ryan, a former postdoctoral fellow of Tatum, realized that these mutants could be used to test for genetic recombination or sexual reproduction in bacteria. In 1945, Lederberg began working with Tatum, who had moved to Yale to begin a microbiology program there. Within a year, Lederberg and Tatum had evidence that bacteria could engage in genetic recombination.⁽²⁹⁾ Discussion of their results at the CSH meeting further undermined the conception of bacteria as Lamarckian organisms.

Since the 1960's, the discovery of genetic recombination in bacteria has been considered to be foundational for molecular biology. In 1946, however, it was perceived as research primarily in microbiology (or bacteriology), and therefore fell within the intellectual jurisdiction of van Niel. When geneticist Beadle heard news of the discovery, he wrote to Tatum, "The story on the sex life of bacteria sounds darned exciting. It looks to me like it is the most important advance in bacteriology in the last hundred years. Congratulations."⁽³⁰⁾ In response Tatum wrote, "It is, we feel, a very exciting field and we will keep you in touch with progress. Dr. van Niel has a preliminary copy of a proposed paper. Perhaps you could get it from him and take a look at it."⁽³¹⁾ Similarly, in a 1947 review of the recent work on bacterial genetics, the bacteriologist Luria called the work of Lederberg and Tatum, "among the most fundamental advances in the whole history of bacteriological science."⁽³²⁾ Luria's article was published in Bacteriological Reviews, a major American journal in bacteriology, sponsored by the SAB.

This disciplinary identification is not surprising when one considers that in 1946 molecular biology was not yet a professional identity, discipline, or even widely-used category of research. The research from which molecular biology was built was necessarily carried out under different disciplinary affiliations of which microbiology was one of the most important. Similarly, the research of Beadle and Tatum on the relationship between genes and enzymes, the work of Luria and Delbrück on mutations in bacteria, and the studies by Avery and colleagues on the "transforming principle" have all been claimed as foundations of molecular biology. It is important to note that Tatum, Luria, and Avery were all trained in bacteriology and were comfortable with that label in the 1940's; Beadle was a geneticist, and Delbrück originally a physicist. The role of genetics and physics has been emphasized in existing histories of molecular biology, while that of bacteriology and microbiology have been relatively obscured.

Research on the genetics of yeasts, the ciliate Paramecium, and Neurospora was also featured at the CSH meeting. Geneticist and protozoologist Tracy Sonneborn discussed cytoplasmic factors and the enzymatic constitution in Paramecium. Sol Spiegelman, a researcher from the Department of Microbiology at the University of Illinois, reported on the role of cytoplasmic and nuclear factors in the genetic control of enzyme formation in yeast.⁽³³⁾ Beadle's colleague David Bonner reported on biochemical mutations in Neurospora. This paper afforded opportunity for discussion of the principle developed by Beadle and Tatum that one gene specifies one enzyme. "The single topic of greatest interest to the audience present at that meeting," molecular biologist Gunther Stent later wrote, "was ...the apparent triumph of the one-gene--one-enzyme theory."⁽³⁴⁾

Van Niel's contribution at the meeting was of a different nature. Van Niel's paper, "The Classification and Natural Relationships of Bacteria," offered a broad biological context in which the new work on microbial genetics could be situated. Van Niel placed bacteria in the context of the origin of life and evolution via a detailed review of bacterial classifications systems proposed from the nineteenth century to the 1940's. He revisited issues he had addressed in publications with Kluyver in 1936 and with Stanier in 1941. As in the earlier works, van Niel emphatically distinguished between rational phylogenies and practical classification systems. Only the former, he argued, constituted scientific knowledge because they were theoretically meaningful and helped pose new research questions. The earlier works had been unapologetic attacks on the SAB-sponsored Bergey's Manual, the standard handbook for bacterial classification. While remaining critical of Bergey's Manual, van Niel offered something of a truce. He was forced to admit that the process of constructing rational phylogenies was far too slow to keep up with the numbers of bacteria being brought into culture collections and described. The need for a workable system for naming and classifying bacteria simply overwhelmed theoretical considerations. Still, he urged his audience not to mistake a practical classification for a theoretically valid one out of intellectual laziness.⁽³⁵⁾

As the 1946 CSH meeting portended, study of the genetics of microorganisms developed into a dynamic research area in the late 1940's and 1950's. One group of investigators, led by Delbrück at Caltech and Luria at Indiana, made the bacteriophage their central object of research. Another group, stimulated by the work of Lederberg on genetic recombination in bacteria, worked hard at finding mutations and mapping genes in bacteria. A third area of activity concerned the problem of adaptive enzymes in bacteria and yeasts. Another area of research inspiring a great deal of excitement at the time concerned the role of cytoplasmic factors in heredity. In all of these areas, studies on microorganisms were central.

From van Niel's point of view, the new research on the genetics of microorganisms attested to the rising fortunes of general microbiology. He assumed that his field could and would absorb this new information into its body of knowledge. What van Niel and others did not appreciate at the time was the potential for this research specialty to break away from its connections to microbiology and become allied with other research agendas.

As a leader of the increasingly important field of general microbiology, van Niel circulated among the elite of experimental biologists and biochemists of the 1940's. After the CSH meeting, van Niel headed back to California for a sabbatical year at Caltech, where he planned to learn "the new chemistry" in Linus Pauling's laboratory. "His concepts strike me as about as fundamental as Lavoisier's," van Niel wrote to Stanier. He thought Pauling's work would make twentieth century chemistry as different from nineteenth century chemistry as the latter was from that of the eighteenth.⁽³⁶⁾ As always, van Niel's interest in science was related to his philosophical standpoint. "Much will depend on what I can still learn," he wrote to Stanier about his sabbatical, "and upon its general bearing on 'science and civilization'."⁽³⁷⁾

At Caltech, Pauling and Beadle were laying out their ambitious plans for

a large-scale program of research in what they generally called "chemical biology" in the 1940's.⁽³⁸⁾ Thanks to maneuvering by Pauling, Beadle had been persuaded to move from Stanford to Caltech in 1945. Beadle and Pauling considered microbiology, along with virus research, to be a cutting edge subject, valuable for the massive project they envisioned.⁽³⁹⁾ Pauling and Beadle were pleased to have the leading exponent of general microbiology close at hand.

During van Niel's sabbatical, C.V. Taylor, the animating spirit and Dean of the School of Biology at Stanford, passed away. Knowing that van Niel would feel Taylor's death keenly, Beadle saw the moment as an opportunity for Caltech. Beadle suggested to Pauling that instability at Stanford might encourage van Niel to consider joining their program at Caltech. In the same letter, Beadle mentioned that he would also like to invite Delbrück to Caltech to lead research on viruses.⁽⁴⁰⁾

Soon thereafter, van Niel received a formal offer from Caltech. The negotiations for the position were complex and for van Niel the decision was not easy. He mulled over the possibilities while stranded in Wyoming by a railroad strike. He took the occasion to read Pauling's The Nature of the Chemical Bond and Bertrand Russell's A History of Western Philosophy. "I have found it superb!" he said of the latter.⁽⁴¹⁾ He later incorporated Russell's book into his course in microbiology.

Despite the strong commitment to experimental biology at Stanford in the 1930's, the outlook for the next decade was clouded. Taylor's death was a personal and professional loss for van Niel. Many of the new faculty appeared to be more interested in teaching than in research. Van Niel was angry that Stanford had failed to keep Tatum, one of the most productive experimentalists in the group, from moving to Yale. The argument that teachers for general biology were more urgently needed than experimentalists had won the day. This outcome had made van Niel pessimistic about the prospects for experimental biology at Stanford.⁽⁴²⁾ Meanwhile, Tatum accepted a position at Yale, where he went on to conduct more path-breaking research on genetics and microorganisms. There were even rumors that Stanford might close the Hopkins Marine Station except for summer programs. On the positive side, Whitaker, a scientist whom van Niel liked and respected, replaced Taylor as the new Dean of the School of Biology.

Despite these doubts, van Niel declined the attractive offer from Caltech. Beadle and Pauling could console themselves with the fact that Delbrück accepted an offer to join them. Van Niel chose to return to the relative isolation and tranquility of the Jacques Loeb Laboratory on the Monterey Bay. His appointment to an endowed professorship eased his decision. After a difficult and disruptive sabbatical year, van Niel was looking forward to settling down for the next few years. He expected "the spirit of 1937-42" to return, he wrote to Stanier, and was pleased to report that even his laboratory technician was working hard again. "Life at the Station is going to be fine again!" he wrote.⁽⁴³⁾

Van Niel's decision to return to the marine station did not mean a retreat from either scientific authority or activity. In the 1940's and 1950's, van Niel's laboratory became a renowned center for the pursuit of microbiological research and for the production of high quality researchers. In the first decade after World War II, Wolf Vishniac, Barbara Wright, Helge Larsen, Barbara Bachmann, and F.G. Lara received doctoral degrees under van Niel. All five became distinguished microbiologists who continued research in van Niel's mode. Two postdoctoral fellows, J.L. Stokes and M.B. Allen, arrived in the mid-1940's and stayed for three or more years.⁽⁴⁴⁾ In 1950, ten postdoctoral fellows joined van Niel. From 1950 to 1952, the "microbiology group" working under van Niel consisted of fifteen students and researchers.⁽⁴⁵⁾ In the summers, van Niel resumed teaching his ten-week course in microbiology. It became world-famous, attracting prominent researchers from around the world to spend several months at the HMS.

Van Niel continued to define his research program in broad biological terms: to explore fully the range of microbial diversity, to understand the physiology and morphology of micro-organisms as wholes, and to determine the ecological role of microorganisms in nature. In the 1940's and 1950's, his laboratory consistently produced important research in microbial physiology, biochemistry, and ecology. Research topics included thermophilic bacteria, blue-green algae, myxobacteria, bacterial fermentations, denitrification, pigment formation, green sulfur bacteria, thiobacilli, hydrogen-oxidizing bacteria, photosynthesis, and protozoan metabolism.⁽⁴⁶⁾

The opposite of an autocratic research director, van Niel gave his students considerable independence in their research and training. Stanier and Doudoroff later described his laboratory as a place where "freedom reigned," even "if it was a freedom that bordered on anarchy." Each student "was free to follow his own scientific interests, to develop his talents in his own particular way and at his own particular pace."⁽⁴⁷⁾ In contrast to what is now typical practice, van Niel did not attach his name to a publication unless he had been directly and substantially involved in the research. Van Niel signed only a few of the thirty-three substantial publications produced by his students and colleagues between 1951 and 1954. He was the sole author of several other publications.⁽⁴⁸⁾

Much of the work produced in van Niel's laboratory was biochemical or biophysical in nature, but it was always directed toward answering broad microbiological questions. Van Niel resisted the impulse to allow biochemical, biophysical, and genetic studies to become aims in themselves. He cultivated the viewpoint that ecological, physiological, biochemical, and biophysical analysis provided complementary perspectives all of which were ultimately necessary for achieving a complete and unified comprehension of nature. Larsen, for example, carried out a broad program of research on the green sulfur bacteria very much in the tradition set by van Niel and Stanier in their respective dissertations. He began by cultivating a group of photosynthetic bacteria known as the green sulfur bacteria, which had not been much studied in the laboratory. He then undertook a systematic investigation of their physiology and biochemistry with special attention to their photosynthetic processes. He compiled his observations in an article modeled on van Niel's publications on the purple bacteria.⁽⁴⁹⁾ In addition to biochemical work, Larsen analyzed the absorption spectra of these organisms and their pigments and determined the quantum efficiency of carbon dioxide assimilation.⁽⁵⁰⁾

At the marine station, van Niel could recover his conception of scientific research as a quest for truth about nature. As in the 1930's, van Niel continued to present microbiology as a great cultural project. For some of his students, this was a new and exciting idea. For those already disposed toward this idea, van Niel's influence reaffirmed their conviction. In 1946, he wrote to Stanier that "career" was "Not the best word or expression!" to refer to a life in science. At the time, a disillusioned Stanier was considering leaving scientific research. Van Niel responded, "Science is still one of the very few things which can be treated as a major value (philosophy), whence it is, however slowly, spreading a great and beneficial influence, even if much of what goes on under that name has preciously little to do with the fundamental nature of science."⁽⁵¹⁾

Van Niel's conception of science as a noble quest for truth sometimes approached the naive and irresponsible. "I believe we ought to learn that an educational institution (not a 'teaching business' à la Berliz [sic] School) cannot make money, not support itself, but depends upon support from outside," he once wrote to Stanier.⁽⁵²⁾ He did not identify who or what from "outside" should support science. In a similar spirit, van Niel was pleased when one of his postdoctoral fellows left a well-paid position at Merck to remain at the HMS without any salary. He wrote to Stanier about the episode, "Jack Stokes has definitely severed his connections with Merck. I like him more and more"⁽⁵³⁾

Despite van Niel's reluctance to muddy his hands with fund-raising, the fact was that money was necessary for research. In the postwar era, expensive equipment like spectrophotometers, the Tiselius apparatus, and radioactive isotopes became standard, indispensable items for cutting edge research labs. Support from the RF kept van Niel's research programs viable. The RF provided funds to van Niel in various ways throughout the 1940's and 1950's, even after it reduced its general support for experimental biology. In 1948, the RF gave van Niel a special grant of $20,000 without him ever applying for it.⁽⁵⁴⁾ Stanford administrators, fearful of losing van Niel to Caltech or another prestigious institution, had approached the RF in search of funds to support his work, apparently without van Niel's knowledge.⁽⁵⁵⁾ Van Niel made sure that Foundation officers were aware of his belief that fund-raising was an improper activity for a scientist. "You probably know that I did not solicit funds, but was told that Stanford University would endeavor to support my research."⁽⁵⁶⁾ When an RF officer visited his laboratory to learn directly about van Niel's research and requirements, van Niel again made clear that he himself had not made any requests for funding.⁽⁵⁷⁾

Although van Niel was reluctant to ask for funding, he did not decline to accept it. To maintain the moral high ground, van Niel stipulated to his patrons that he retain complete freedom in research. In 1948, he wrote to Weaver at the RF, "that your proposal would leave me virtually complete freedom in the way of apportionment is a reason for my gratitude. I can assure you that expenditures under the grant, if this materializes, will not be lightly made."⁽⁵⁸⁾ The RF responded by awarding van Niel a three-year grant, which allowed him to purchase expensive equipment like centrifuges and spectrophotometers and specialty reagents like radioisotopes.⁽⁵⁹⁾

Van Niel's strategy, if it may be fairly called that, was to represent a certain moral ideal of the scientist. Scientific managers, besieged by more entrepreneurial researchers, were impressed by van Niel's style as well as his science. In 1951, an RF report noted, "In these days of large cooperative teams, gleaming laboratories, and equipment often costing tens of thousands of dollars, it is sometimes forgotten that the essential ingredient in genuinely original research still lies in the individual scientist. An outstanding example is Dr. C.B. van Niel." The RF then awarded van Niel a three-year grant of ten thousand dollars per year.⁽⁶⁰⁾ The RF managers considered van Niel to be a bargain and remarked upon his comparative thriftiness.⁽⁶¹⁾ In 1954, van Niel asked for extension of an RF grant because, he lamented, he had been too busy to carry out his own work. From 1951 to 1952, he had been kept busy supervising fifteen post-doctoral fellows and graduate students who had joined his laboratory at the HMS.⁽⁶²⁾ A favorite of the RF, van Niel was granted his request.

From 1947 to 1954, van Niel's laboratory continued to be a productive center for research in general microbiology. During this period, general microbiology appeared to be a dynamic, cutting-edge field of research. Van Niel's research continued to focus on the morphology, ecology, physiology, and biochemistry of microorganisms, but not on genetics. He left research on this topic to others, but followed its developments carefully. In the 1940's and early 1950's, general microbiology flourished in van Niel's laboratory and in research institutions around the world.

C. General Microbiology at Berkeley

Van Niel's students were especially well poised to take advantage of the new importance of general microbiology in the postwar years. Leading academic institutions approached Stanier, known to be van Niel's protégé, even before the war ended. McGill University, Indiana University, the University of Texas, and the University of California all expressed interest in him. After returning from his European tour of 1945 to 1946, Stanier joined the Department of Bacteriology at Indiana University on a one-year appointment. Indiana wanted to keep Stanier, but he was extremely unhappy there.⁽⁶³⁾

In 1946, however, a new, very attractive opportunity began to develop. At the University of California in Berkeley, President Sproul undertook a campaign to build up the biological sciences to the high level of the physical sciences. He had special ambitions for improving biochemistry.⁽⁶⁴⁾ In the mid-1940's, the Bacteriology Department was also poised for modernization. Karl F. Meyer, the prominent pathologist, resigned as chairman of the Bacteriology Department in 1946 in preparation for retirement. Doudoroff expected the department to improve greatly under the new chairman, A.P. Krueger, a medical bacteriologist with some sympathy for general microbiology. For Doudoroff, "improvement" meant increasing the presence of general microbiology in the department. Doudoroff was delighted on professional and personal grounds when the department became interested in hiring Stanier. "I would very much like to have you as a colleague," Doudoroff wrote to Stanier, "(as a matter of fact, I do not know of anyone I would rather see here, both for my own sake and for the sake of the department)."⁽⁶⁵⁾ Trying to persuade Stanier to come to Berkeley, he described the landscape of science on the West Coast in the following terms: "In California, we have not only Berkeley," he wrote, "but also the Hopkins Marine Station and Cal Tech."⁽⁶⁶⁾

Van Niel, of course, encouraged Berkeley to appoint Stanier to its faculty.⁽⁶⁷⁾ To replace Meyer with his protégé would represent another triumph for general microbiology. Van Niel was thrilled when Stanier was offered the position.⁽⁶⁸⁾ Doudoroff, too, was delighted. In 1947, Stanier joined Doudoroff and Barker, then in the Department of Biochemistry, as the third important student of van Niel on the Berkeley faculty. With Barker located nearby, there were ample opportunities for collaboration and informal discussion. All three disciples remained in close contact with van Niel. In the late 1940's, Barker and van Niel continued radioactive tracer experiments they had begun during the war.⁽⁶⁹⁾ Stanier and Doudoroff both spent the summer of 1947 at the marine station, and they continued to visit several times per year during the next two decades. At Berkeley, Stanier became a forceful presence and a powerful advocate for general microbiology. It became an important expansion point for van Nielian microbiology.

The appointment of Edward Adelberg to the Department of Bacteriology in 1949 brought expertise in genetics and a moderating influence on departmental politics to the Berkeley bacteriology group. During the next dozen years, Doudoroff, Stanier, and Adelberg developed an extraordinarily close-knit and cooperative laboratory group. Collectively, the three scientists offered an outstanding combination of expertise. Doudoroff was the best biochemist in the group, Adelberg the expert in genetics, and Stanier the visionary who maintained a broad view of microbiology as a part of biology.

Stanier and Doudoroff faced a very different institutional situation than did van Niel. At Berkeley, there was no Department of Biology, but rather a motley collection of organizational structures dealing with the life sciences. Departments of Zoology, Botany, and Physiology, like those dissolved at Stanford in the 1930's, persisted at Berkeley until 1989. The organization of Berkeley belied the concept of biology as a unified science of life. The appointment of biochemist Wendell Stanley to the Berkeley faculty in 1948 did nothing to overcome disciplinary or departmental boundaries. In 1938, Stanley had successfully crystallized the tobacco mosaic virus (TMV). He proposed to make the physical and chemical analysis of TMV the center of a new biochemistry.⁽⁷⁰⁾ Stanley launched a successful research program, but failed to serve as a leader for the life sciences more generally. His uncompromising emphasis on the biochemistry of the macromolecular structure of TMV created conflicts with scientists like Barker who were interested in metabolic transformations of small molecules.

Stanier and Doudoroff, deeply committed to general microbiology, faced another kind of dilemma as members of a Department of Bacteriology with a distinguished tradition in medical research. Inevitable conflicts with the medical bacteriologists over curriculum and research programs occurred sporadically from the 1940's to the 1960's with varying degrees of seriousness and intensity.⁽⁷¹⁾ Despite their differences, the faculty interested in pathology and the general microbiologists were dependent on each other. The medical faction, led by Krueger and Sanford Elberg, who had trained with Karl Meyer, advocated a biological approach to understanding pathology. They saw themselves as leading a more enlightened approach to medical bacteriology. "Medical bacteriology, fascinated by the rich rewards granted by the unilateral search for new causes, at first failed to realize that infective diseases are biological manifestations of parasitism," wrote Elberg.⁽⁷²⁾ Elberg often used the phrase "experimental pathology and immunology" to describe his interests instead of the term medical bacteriology, which he associated with a less rigorously scientific approach than he favored.⁽⁷³⁾ The general microbiologists, on the other hand, were dependent on the medical bacteriologists or pathologists to justify the existence of a distinct Department of Bacteriology. The generalists doubted they could maintain a stable department in the university without them.⁽⁷⁴⁾

Unlike their mentor at the marine station in Monterey, Stanier and Doudoroff were frequently embroiled in political matters. Both Stanier and Doudoroff had sympathy for leftist political positions, which endangered their careers at Berkeley despite the high quality of their research and teaching. Their political disagreements with Krueger and Elberg exacerbated scientific differences. During the Second World War, Elberg worked at Camp Dietrick on secret bacteriological warfare research for the U.S. Army.⁽⁷⁵⁾ After the war, Stanier thought the SAB should take a stand against bacteriological warfare and proposed to submit a resolution to the society. In 1947, he wrote to Waksman, "A heavy responsibility rests on those scientists whose professional training permits them to visualize the dangers of biological warfare; only the microbiologists have the scientific authority to make public pronouncements on this matter."⁽⁷⁶⁾ One of the greatest sources of conflict among the bacteriologists was the presence of a Naval Biological Laboratory in the Life Sciences Building. In 1935, Krueger, who held a Navy commission, created the Naval Medical Research Laboratory. In 1940, Krueger arranged for the Navy to install the laboratory on the fifth floor of the Life Sciences Building. The laboratory remained there until 1950, when it was moved to the Oakland Naval Supply Station. Although they had objected to the presence of a military laboratory on a university campus, Doudoroff and Stanier angled (fruitlessly as it turned out) to acquire equipment from the laboratory when it moved.⁽⁷⁷⁾

In 1949, Doudoroff got into serious trouble when he criticized the U.S. and praised the U.S.S.R. while a guest of Krueger at a party at the Alameda Naval Air Officers's Club.⁽⁷⁸⁾ After his comments were reported to the F.B.I., Doudoroff was investigated and charged with disloyalty. He was permanently disqualified from serving on any panels concerned with funding from the U.S. government.⁽⁷⁹⁾ A year later, when a bill was passed requiring all employees of the state of California to swear an Oath of Loyalty, Doudoroff and Stanier at first refused, like many other University of California faculty. Stanier even threatened to resign his professorship over the matter. In the end, Stanier signed the Loyalty Oath, albeit "with the greatest distaste and reluctance," as he wrote to President Sproul.⁽⁸⁰⁾

Other institutions were prepared to exploit these political controversies to obtain top researchers in general microbiology. In 1950, the Yale administration asked Stanier if he would be interested in joining their faculty. After Stanier declined, Yale asked Barker if he might be available "because of the present situation in California."⁽⁸¹⁾ In 1951, serious attempts were made to attract Stanier to the Institute of Radiobiology and Biophysics at the University of Chicago. Manhattan Project veteran Aaron Novick, then a research associate working with physicist Leo Szilard, hoped that Stanier would join them. He described the Institute in attractive terms. He told Stanier that there was considerable freedom in research there and no teaching responsibilities. He also pointed out that many of the most important researchers working on microbial genetics were close by at the Universities of Indiana, Illinois, and Wisconsin. "We are within 120 miles of Josh, Salva, Sol, and Gunny," he wrote to Stanier, referring to Lederberg, Luria, Spiegelman, and microbiologist I.C. Gunsalus respectively.⁽⁸²⁾ In 1951, Stanier was offered a position at Chicago with choice lab space and all the modern equipment, sterilizing rooms, cold rooms, counter rooms, and sufficient space for a Tiselius apparatus and a high precision spectrophotometer. His invitation specifically mentioned that the department would be "delighted" to have Stanier "give a van Nielian microbiological course."⁽⁸³⁾ Despite these attractions, Stanier chose to stay at Berkeley, where he continued to cultivate general microbiology for the next two decades.

Committed to van Niel's intellectual and philosophical views of science, Doudoroff and Stanier worked closely together and continued a broad program of research in general microbiology. Stanier's research focused on a variety of problems in bacterial physiology, including the oxidation of aromatic compounds and amino acids.⁽⁸⁴⁾ He went on to study the structure of the nonsulfur purple bacteria and the synthesis of photosynthetic pigments. In collaboration with Berkeley biochemists Arthur Pardee and Howard Shachman, Stanier made one excursion into analyzing the organization of macromolecules in sub-cellular fractions prepared through analytical centrifugation.⁽⁸⁵⁾

One of Stanier's first research projects at Berkeley was to investigate the phenomenon of "enzyme adaptation," a topic that played a central role in the emergence of molecular biology. In 1947, while investigating the metabolism of aromatic compounds by Pseudomonads, a group of aerobic bacteria, Stanier made an intriguing observation. He found that cells grown on the aromatic compound mandelate were "adapted" to use not only this metabolite, but a whole series of other intermediates within one pathway. He called this phenomenon "simultaneous adaptation." By the early 1950's, the study of enzyme synthesis in bacteria had become a lively and rapidly moving research topic. In 1950, Stanier won the prestigious Eli Lilly and Company Award in Bacteriology and Immunology for his work in this area. Accepting the award at the SAB's annual meeting in May, Stanier gave a lecture on the "Problems of Bacterial Oxidative Metabolism."⁽⁸⁶⁾ Stanier returned to the problem of enzyme adaptation several times in the next two decades.⁽⁸⁷⁾

In the 1940's and 1950's, Doudoroff's research was oriented toward the analysis of sugar metabolism in bacteria. These investigations revealed the numerous and complex biochemical pathways involved in the synthesis and break-down of various kinds of sugar molecules. Doudoroff also identified many of the enzymes involved in these processes.⁽⁸⁸⁾ One postdoctoral fellow, Noberto Palleroni, arrived in 1953 to work with Doudoroff on carbohydrate metabolism in Pseudomonas saccharophila. He remained with the bacteriology group for seventeen years.

In the late 1940's and early 1950's, the boundaries between microbial genetics and general microbiology were fluid and vague. Both Stanier and Doudoroff maintained close connections with the leaders of the developing field of microbial genetics. Doudoroff devoted his sabbatical year 1949 to 1950 to learning bacterial genetics. A Guggenheim Fellowship in hand, Doudoroff visited some of the leading centers of research in the field, including the Pasteur Institute, Spiegelman's laboratory at the University of Illinois, and Lederberg's group, then at the University of Wisconsin. Doudoroff was "glad to discover how ridiculously easy and beautiful Lederberg's techniques are," he wrote to Stanier. "I intend to incorporate them in Bact 1 eventually," he continued, referring to the introductory course in general microbiology he taught.⁽⁸⁹⁾

In the year 1951 to 1952, Stanier made a circuit similar to the one made by Doudoroff. He spent the first half of his sabbatical with I.C. Gunsalus at the University of Illinois. In collaboration with his host and microbiologist C.F. Gunsalus, Stanier continued studies of the metabolism of mandelic acid in Pseudomonads, which he had begun in 1947. In the process, the trio of investigators found five "adaptable" enzymes.⁽⁹⁰⁾ Stanier then traveled to Paris to work on enzyme adaptation with Monod at the Pasteur Institute. There, Stanier found a group of colleagues who shared both his scientific outlooks and his cultural sensibilities. He initiated warm and lasting friendships with Monod, Lwoff, Lwoff's wife Marguerite, and Germaine Cohen-Bazire, a student of Monod. Like van Niel and Stanier, the Pasteur group regarded science, including microbiology, as a kind of cultural and philosophical endeavor.⁽⁹¹⁾ At Berkeley, Stanier and Doudoroff had worked to create a research culture in their laboratories similar to that they had encountered with van Niel. "Thanks for the letters," Doudoroff wrote to Stanier in Paris, "You are with us in spirit, if not in simultaneously adaptive body....There is a wonderful spirit of unity and cooperation, which even people in other departments are becoming jealous of."⁽⁹²⁾

Stanier arrived at the Pasteur Institute during a dynamic period of research on bacterial genetics, enzyme adaptation, and phage genetics. At the Pasteur Institute, André Lwoff directed two main lines of investigation related to bacterial heredity in the Service de Physiologie Microbienne, a department founded in 1938. In the 1920's, when working summers with the protozoologist Edouard Chatton, Lwoff had become passionately interested in the ciliates, a group of protozoans. After receiving a degree in medicine in 1927, he continued to work on the morphology and physiology of the ciliates. In the 1930's, he undertook research on the nutritional requirements of bacteria and other microorganisms. During these studies, he showed that some microorganisms require specific growth factors in analogy to the vitamin requirements of more complex organisms.⁽⁹³⁾

In 1949, inspired in part by the CSH meeting of 1946, Lwoff embarked on a new research topic, the phenomenon known as lysogeny.⁽⁹⁴⁾ Two decades before, researchers at the Pasteur had observed that bacteriophage infection did not always lead to the immediate destruction of the bacterium. Under some conditions, the bacteriophage appeared to enter the bacterial host cell and remain quiescent for a period of time. For reasons not at all understood, the phage would sometimes become active and resume a typical pattern of replication within the bacterial cell, culminating in the lysis of the cell. Lwoff sought to bring this phenomenon under experimental control by determining the specific physical and chemical conditions that would stimulate the phage to change from a latent to an active state.

Jacques Monod led the second line of investigation, the study of enzyme adaptation in bacteria. Monod took a circuitous path to the problem. A graduate of the Sorbonne, where he had studied zoology, Monod spent the year 1936 at Caltech learning Drosophila genetics. When he returned to France, he resolved to study something that seemed simpler, like protozoa. He carried out several studies of the growth of protozoa and occasionally discussed his work with Lwoff, the local authority on protozoan physiology. Lwoff advised Monod to work on bacteria that could grow on a medium that was completely defined biochemically so that quantitative studies of microbial growth would be possible.⁽⁹⁵⁾

Monod studied bacterial growth quantitatively for his thesis at the Sorbonne. His work showed that the rate of growth of a bacterial culture was a function of substrate concentration. During these studies, he noticed an intriguing phenomenon. Monod found that bacteria growing on certain combinations of sugars exhibited an unusual growth pattern. The classic growth curve for bacteria, in which the number of cells in a culture was plotted against time, yielded a simple "S" shaped curve. The first, relatively flat part of the curve was generally called the lag phase of growth. This was followed by a period of logarithmic growth, usually called log phase, followed by a slowing to "stationary phase." Monod found that Bacillus subtilis showed this typical pattern of growth when incubated with either sucrose or glucose or both sugars together. However, if these cells were incubated with certain other pairs of sugars, the bacterial culture exhibited a two-phase or double-S curve growth pattern. Monod termed this phenomenon "diauxie." With Lwoff's help, he interpreted the growth pattern in terms of enzyme adaptation. After a lag phase, the bacteria appeared to be able to adapt to grow on a new sugar. In 1945, Monod formally joined Lwoff's department at the Pasteur Institute, because no one at the Sorbonne found his research interesting.⁽⁹⁶⁾

Published during the war, Monod's thesis became better known after the 1946 CSH meeting, which he and Lwoff attended, and when published in article form in 1949 in the Annual Review of Microbiology. In 1949, Monod conceived of this research as central to microbiology: "The study of the growth of bacterial cultures does not constitute a specialized subject or branch of research: it is the basic method of Microbiology. It would be a foolish enterprise... to attempt reviewing briefly a 'subject' which covers actually our whole discipline."⁽⁹⁷⁾

After entertaining the idea of working on bacteriophage, Monod settled on pursuing enzyme adaptation in the bacterium E. coli. He focused on the synthesis of the enzyme beta-galactosidase in response to the sugar lactose. Representing a continuation of his studies on bacterial growth, this project developed into the research on gene function that won Monod a Nobel Prize in 1965. By that time, he perceived this research as part of molecular biology.⁽⁹⁸⁾ In 1952, he still construed it as microbiology. He concluded an address on the genetic and chemical factors involved in the synthesis of beta-galactosidase with this comment: "Ce qui fait la difficulté et la beauté de notre discipline, la Microbiologie, c'est que chaque problme, chaque expérience se ramne, et nous ramne, aux questions les plus générales et les plus fondamentales de la Biologie."⁽⁹⁹⁾

At the Pasteur, Stanier and Monod undertook a project to create new language that reflected new concepts of bacterial heredity. These concepts emerged in part from studies on enzyme adaptation. Stanier and Monod conspired to reformulate enzyme adaptation as enzyme induction. The terminology that they advanced, discussed in detail in the next chapter, became a part of the working vocabulary of molecular biology.

After Stanier's return to Berkeley, the connections between the Pasteur group and his laboratory continued. In 1953, Germaine Cohen-Bazire came to Berkeley as a postdoctoral fellow with Stanier. She brought with her considerable experience in working on the regulation of the synthesis of the enzyme beta-galactosidase in bacteria, the central problem under study in Monod's laboratory.⁽¹⁰⁰⁾ She spent the summer of 1954 auditing van Niel's lectures in microbiology. At Berkeley, Cohen-Bazire began studies on the regulation of pigment synthesis in non-sulfur purple bacteria, the organisms van Niel had first studied comprehensively. Her work formed a bridge between the research approaches of the Pasteur group and van Nielian microbiology. She went on to productive research on pigment mutants in photosynthetic bacteria, the role of carotenoids in photosynthesis, and the ultra-structure of bacteria.⁽¹⁰¹⁾ In 1956, Stanier and Cohen-Bazire were married. She remained an important practitioner of general microbiology at Berkeley for the next two decades.

D. Transmitting Crafts and Concepts -- The Summer Course in General Microbiology, 1947-1954

In the 1940's and 1950's, microorganisms, especially bacteria and viruses, attained a new place in the working economy of experimental biology. As van Niel remarked in 1949:

It is no longer unusual to find a large fraction of the pages of physiological and biochemical journals occupied by publications dealing with activities of fungi, protozoa, and bacteria. Even in the field of genetics, the mold Neurospora, the yeasts, Escherichia coli, Paramecium, and bacteriophages are successfully competing with Oenothera, Zea mais and Drosophila.⁽¹⁰²⁾ Two years later, Milislav Demerec quantified the shift toward microorganisms for genetic studies. To celebrate the tenth anniversary of his directorship of the Cold Spring Harbor laboratory, he chose to revisit the topic taken up in 1941, "Genes and Mutations." "One of the most remarkable developments of these ten years," he noted, "concerns the organisms used in gene studies. In 1941, about thirty per cent of the Symposium papers reported research carried on with Drosophila, and only six per cent dealt with microorganisms; whereas this year only nine per cent of the papers relate to Drosophila and about seventy per cent to microorganisms."⁽¹⁰³⁾

As microorganisms became important experimental material for a variety of research programs, van Niel's technical and practical expertise became increasingly valuable to an elite group of investigators. Researchers interested in the physiology, biochemistry, and ecology of microorganisms continued to be an important audience for van Niel, but the explosion of interest in microbial genetics created a new constituency for his course. In the 1940's and 1950's, scientists from around the world competed for admission. Its distinguished graduates include the Nobel Prize winners Arthur Kornberg, Paul Berg, and Konrad Bloch, and numerous leading researchers in a wide range of biological fields. The class of 1948, for example, included Leo Szilard, the physicist renowned for his involvement in the atomic bomb project, and his colleague the physical chemist Aaron Novick, another prominent veteran of the Manhattan Project. Already a brilliant achievement in the 1930's, van Niel's course in microbiology became a unique and uniquely valuable resource after World War II.

As in the 1930's, the course could be experienced on several levels. Its intertwined functions included practical instruction, personal cultivation, social legitimation, and even a kind of redemption. The summer course in microbiology continued to be a powerful expression of van Niel's conception of microbiology and a useful means for winning converts to his cause. In practical terms, the course was a godsend for those interested in learning how to work with microorganisms. In ten weeks, a student could receive thorough training in the theory and practice of general microbiology from a masterly teacher. As it became a part of the common experience of a group of elite scientists, van Niel's course came to provide a kind of social legitimation. By the 1950's, it played a very important role in credentialing. Like association with Delbrück's group at Caltech, or a stint at the Pasteur Institute, participation in van Niel's course was a sign of acceptance in the new elite of the life sciences. Ten weeks in van Niel's laboratory on the Monterey Bay could also be a redemptive experience. It could provide assurance that science could still be pursued as a kind of spiritual quest for comprehension of nature.

The migration of physicists to new fields of research, especially the life sciences, is a distinctive feature of postwar science. Van Niel's course played a special role in training physical scientists who sought to conduct research in the biological sciences. In the 1940's and 1950's, van Niel's course in general microbiology and Delbrück's course in phage genetics played complementary roles in training researchers, especially physical scientists, for the new biology. Until the present study, the central importance of van Niel's course in this process has largely been overlooked, in part because of the attention given by historians to Delbrück and the phage course. Van Niel's course provided a place where accomplished physical scientists or other trained professionals could learn the basics of a new field. Here, a physicist could learn how to focus a microscope, how to prepare culture media, how to identify bacteria, how to converse with biologists as a professional, and how to think like a microbiologist. Van Niel's course was in many ways more broadly useful than Delbrück's phage course. It was more than three times as long and presented a broad survey of the microbial world.

Several scholars have noted that the boundaries between medical research and basic research became more fluid after World War II. Researchers with backgrounds in medicine formed a second important constituency for van Niel's course. Scientists trained in various branches of biology also came to the course to learn about microbial physiology and ecology.

In general, van Niel's course brought together scientists and students with diverse interests and backgrounds and gave them a common experience in practicing microbiology. It provided the opportunity for formal and informal exchanges among scientists with diverse backgrounds. It created a temporary space where old identities could be loosened and new ones tried out. The course facilitated the dissolution of disciplinary boundaries and the formation of new scientific identities. In these respects, van Niel's course may be viewed as a "mediating site," that is, as a specific time and place in which crucial exchanges of information, techniques, and concepts occurred, a place in which disciplinary and cultural boundaries could be easily crossed.⁽¹⁰⁴⁾

The class of 1948 illustrates these points. That year, van Niel admitted thirteen regular students and four auditors for the ten week session. His graduate student, "the beautiful Barbara Wright," served as teaching assistant.⁽¹⁰⁵⁾ The auditors included his postdoctoral fellows, Helge Larsen, a Norwegian microbiologist, Mary B. Allen, an American biologist, and the physicist Leo Szilard. Szilard had played a crucial role in launching the program that became the Manhattan project. Physical chemist Novick, who had begun a research collaboration with Szilard, signed on to the summer course as a full-time student along with Roderick Clayton, Delbrück's first graduate student. At Caltech, Clayton was pursuing a joint Ph.D. in physics and biology. In contrast, Ralph Lewin, then a graduate student at Yale, had a thoroughly biological background. He specialized in the biology and ecology of the marine algae. Like Lewin, Paul Silva, a botanist from Berkeley, brought a strong biological background to the class.

Lewin was skeptical, at first, of the value of van Niel's teaching which he had heard highly praised. "Why is this kindly old chap asking such simple questions?" he wondered. Van Niel typically began his course by asking, "What is microbiology?" Soon, however, Lewin had a change of perspective. "I began to realise the cunning pedagogy of it all, and from then on I became a devotee." In his own teaching, Lewin later adopted some of van Niel's pedagogical techniques.⁽¹⁰⁶⁾

For physical chemist Novick, the course was an essential part of his training to conduct research in biology. "I was so terrified of microorganisms," said Novick, "not because I was afraid of getting sick or anything. I was afraid that I would screw up." "Van Niel's course gave me the background I needed," he continued, "and the confidence to experiment with microorganisms.⁽¹⁰⁷⁾ Novick was assisted by the fact that his lab partner for the course was Wolf Vishniac, a graduate student with van Niel. Szilard, too, benefitted from van Niel's course. Szilard's initial lack of biological knowledge impressed Lewin, as did his quickness in learning and general perceptiveness.⁽¹⁰⁸⁾

Several studies have emphasized the importance of Delbrück's phage course in training physical scientists for biological research in the postwar period. Some accounts create the impression that the phage course rapidly and single-handedly transformed physical scientists into researchers capable of revolutionary work in biology. A widely cited encomium from Novick has reinforced this perception. Delbrück's course provided, he wrote,

...a biology that had been made comfortable for people with backgrounds in the physical sciences. In that three-week course, we were given a clear set of definitions, a set of experimental techniques, and the spirit of trying to clarify and understand. It seemed to me that Delbrück had created almost single-handedly, an area in which we could work, and after the three-week course we felt ready to embark on our own without further preparation.⁽¹⁰⁹⁾ It is important to appreciate that this passage derives from a collection of reminiscences written in honor of Delbrück and edited by molecular biologist Gunther Stent and colleagues.⁽¹¹⁰⁾ Despite Novick's widely cited comments on the transforming power of the phage course, it was not by itself sufficient to transform him into a competent researcher in biology. In fact, Novick and Szilard attended van Niel's course the summer after taking the phage course. Novick even found it worthwhile to attend van Niel's lectures a second time in 1949.⁽¹¹¹⁾

Several studies on the relationships between biology and physics imply or state that physicists generally considered biologists to be their intellectual and social inferiors. In her study of the RF, for example, Abir-Am has written that the biology in the 1930's was "underdeveloped" and dependent on physicists who, in collaborative projects, managed their "biological assistants who were subordinate to them socially and intellectually."⁽¹¹²⁾

With regard to van Niel, this description is incorrect. In fact, physicists who wanted to work in biology were dependent on the expertise of scientists like van Niel and Stanier. There is no evidence that van Niel or Stanier were intimidated intellectually or socially by physicists like Szilard. A letter van Niel wrote to Stanier in May of 1947 is indicative of their attitudes:

Dr. Leo Szilard, atomic physicist from Chicago, came here to-day to talk about various biological matters. He showed a particular interest in the myxobacteria,...and I advised him to try and get in touch with you....You may look forward to a very exciting discussion -- if you can find the time and opportunity for it; which I hope you will.⁽¹¹³⁾ While in Pacific Grove, Szilard achieved an insight that built on an idea he had the year before. In 1947, Szilard and Novick met Monod when they were at Cold Spring Harbor for both the symposium and the phage course. In discussion with Monod, Szilard proposed the idea that bacteria could be grown in a continuous culture system, rather than in glass flasks or fermentors, the so-called "batch culture" method. In such a system, bacteria would be removed from the culture at the same rate at which they reproduced. While in Pacific Grove, Szilard realized that if bacteria were removed and the growth medium were re-supplied at constant rates, then the culture would maintain itself in a steady-state. The population of cells would be more homogeneous with respect to their physiological state than would cells growing in a conventional batch culture. Szilard called this the "chemostat principle." At the end of van Niel's summer course, Szilard and Novick returned to Chicago to construct a device based on this principle. It proved useful for numerous kinds of genetic and physiological studies on bacteria.⁽¹¹⁴⁾

There is no evidence that physicist Szilard viewed microbiologist van Niel with anything other than respect. In 1950, Szilard sent van Niel copies of papers he had written with Novick on the chemostat. In the accompanying note, Szilard wrote, "The enclosed manuscripts which are now in print might interest you, particularly since Novick and I are generally regarded as your pupils and you should be blamed for any mistakes which we might make."⁽¹¹⁵⁾

In the postwar era, van Niel's course was at least as important as the phage course in training physical scientists for biological research. Many of Delbrück's students and colleagues took van Niel's course, as had Delbrück himself in 1940. A.H. Doermann, the first teaching assistant in the phage course, was a student in van Niel's course in 1942. It is possible that van Niel's course provided Delbrück with a model for an intensive, specialized summer course in research.⁽¹¹⁶⁾

Not only did Delbrück's graduate student, Roderick Clayton, take van Niel's course, he elected to pursue research in the biophysics of photosynthesis, not phage genetics. He chose to study the purple bacterium, Rhodospirillum rubrum, the organisms van Niel had studied in his path-breaking research on photosynthesis. Clayton's subsequent research in bacterial photosynthesis is more closely related to van Niel's work than to Delbrück's genetic work on phage genetics.⁽¹¹⁷⁾ After completing his Ph.D. at Caltech in 1951, Clayton joined van Niel as a postdoctoral fellow on a Merck fellowship. He continued to study the biophysics of photosynthesis for his entire career. Delbrück, too, returned to the problems of light and life in 1950. Convinced that research on phage genetics was well underway and would proceed productively without him, Delbrück decided to study phototropism in the mold Phycomyces. It would be interesting to know if Delbrück consulted with van Niel concerning his choice of organism or his new research direction. The lack of any extant correspondence between van Niel and Delbrück makes this possibility difficult to assess.

Seymour Benzer, now a prominent molecular biologist at Caltech, serves as another important example of the complementary roles of the phage course and van Niel's course in training physical scientists for biology. Benzer obtained a Ph.D. in solid state physics from Purdue in 1947. After teaching for a year, he was appointed to a position as biophysicist at Oak Ridge National Laboratory. In 1949, Benzer applied to Delbrück for a postdoctoral position. In his letter of application, Benzer specifically pointed out that he would take van Niel's course in addition to the phage course in order to prepare for his new research direction.⁽¹¹⁸⁾ Benzer became an important member of the phage group while at Caltech. He completed his acculturation with a year at the Pasteur Institute, from 1950 to 1951.⁽¹¹⁹⁾ In 1953, he began a detailed analysis of the "fine-structure" of the gene in bacteriophage.

In addition to Clayton, van Niel's course in microbiology was attended by two more graduate students of Delbrück who became prominent scientists. A. Dale Kaiser, now a molecular biologist at Stanford, took van Niel's course in 1952. He went on to work on bacteriophage genetics as a graduate student with Delbrück and completed a Ph.D. at Caltech in 1954. He spent the next two years working at the Pasteur Institute in the department of microbiology directed by Lwoff. Kaiser studied the interactions of the bacteriophage and the bacterial host cell. His later research concerned nucleic acid biochemistry. Bruce Ames, now a prominent molecular biologist at Berkeley, was also a Caltech graduate student when he took van Niel's course in 1952.

A second important constituency for van Niel's course was medically trained researchers. For many scientists who came to van Niel's course, its value was precisely that it presented the study of microorganisms within the framework of biology, not medicine. In the postwar era, this opportunity proved especially valuable for physicians and other medically-trained researchers seeking to undertake fundamental research. The course provided a very different context from medical pathology in which to consider the nature and significance of microbial life.

The bacteriologist Salvador Luria, for example, needed no training in the techniques of microbiology when he planned to attend van Niel's course. In addition to his formal training in the subject, Luria had already carried out ground-breaking studies on bacterial genetics in collaboration with Delbrück in the early 1940's. Nonetheless, he tried to find time to attend van Niel's course. In 1947, his wife wrote to Stanier, "We talk about van Niel's course and a summer at Pacific Grove so much that we'll soon come to believe it. I won't be sure of getting there until I hear you goading me into a good healthy curse."⁽¹²⁰⁾ Luria planned to spend the summer of 1950 with van Niel, but did not because he moved from the University of Indiana to Illinois that summer.⁽¹²¹⁾

For Luria, the main attraction of van Niel's course may have been to learn how a subject with medical origins and associations could be recast as a part of general biology. In the late 1940's, Luria was charged with teaching virology at Indiana, a university with a distinguished tradition in general biology. "The problem that faced me in 1946," he later wrote,

was planning a course in virology for...students in biology and biochemistry, who had no medical orientation and no background in histopathology, in a university that was justly proud of its reputation as a center of experimental biology. I could teach either a watered-down course in virus disease or organize a new type of course, in which virology would be presented as a biological science, like botany, zoology, or general bacteriology.⁽¹²²⁾ There is little doubt that Luria's model for "general bacteriology" as a biological science was the science articulated by van Niel and his disciples. Stanier and Luria were close friends throughout their careers, and the latter frequently consulted the former about microbiological matters. Luria is perhaps best known as having been the graduate advisor of James D. Watson, who in collaboration with Francis Crick proposed a structure for DNA in 1953. Generally considered to be a founder of molecular biology, Luria held appointments in departments of bacteriology or microbiology from 1943 to 1964.

Bernard Davis serves as a second example of a medically trained researcher who turned to basic research in microbial genetics via training in both the phage course and van Niel's course. At the end of the Second World War, Davis was charged with setting up a basic science laboratory for the new Tuberculosis Control Unit within the U.S. Public Health Service (USPHS). To prepare for this position, he initially sought training with Dubos at the Rockefeller Institute. While recovering from tuberculosis, which he acquired by working too carelessly in the laboratory, he read about Beadle's work on biochemical mutants in Neurospora. It occurred to him that one could select mutants in bacteria unable to grow in a given medium to which penicillin was added. The penicillin would kill only the actively growing cells; the mutants would therefore survive. His success in implementing this idea turned his research interests to bacterial genetics. He later wrote, "And though I took the phage course...which initiated a treasured friendship with Max Delbrück -- I still did not get deeply into bacterial genetics itself. Van Niel's famous summer course...had a stronger influence on my interests and my approach to problems."⁽¹²³⁾ Davis was an auditor in van Niel's course in 1949. Taking advantage of biochemical and genetic approaches, Davis spent most of his career analyzing biochemical pathways in bacteria. His research on the biosynthesis of aromatic compounds, for which he became well-known, had far more in common with Stanier's work than with Delbrück's. Davis's distinguished career in research encompassed bacterial genetics, amino acid biosynthesis, the mechanism of antibiotic action, and protein transport across cell membranes. In 1968, he became Professor of Bacterial Physiology at Harvard Medical School.

Harry Eagle, Ole Maaløe, Arthur Kornberg, and Paul Berg provide more examples of medical researchers who obtained training in general microbiology from van Niel and then undertook important basic research. From 1947 to 1949, Eagle served as scientific director of research at the National Cancer Institute. He was then appointed chief of the laboratory for experimental therapeutics at the Microbiology Institute at NIH, a position he held until 1958. He enrolled in van Niel's course in the summer of 1950.

Ole Maaløe, a Danish researcher trained in medicine, found his way to elite research in basic biology through the complementary paths of the phage course and van Niel's course. He began his transition to fundamental research by studying with the biophysicist Arne Tiselius at Uppsala from 1947 to 1949. He then spent part of the year 1951-52 in Delbrück's laboratory at Caltech and part of the year with van Niel. Maaløe took van Niel's course in microbiology in 1952. Maaløe became well known for research he carried out in collaboration with James D. Watson, then a graduate student, in 1951 and 1953. Using radioactive phosphorous labeling techniques, they investigated the transfer of nucleic acids from parental to progeny bacteriophage.⁽¹²⁴⁾ Maaløe became a friend of Stent and was admitted into the circle of researchers around Delbrück, called the phage group. He was later invited to contribute to the Festschrift for Delbrück, Phage and the Origins of Molecular Biology. His entry created the inaccurate impression that Delbrück was his principal scientific influence. When he returned to Denmark, however, he established a program in bacterial physiology unmistakably influenced by van Niel's approach. In 1958, he was called to the newly created chair in microbiology at Copenhagen University.⁽¹²⁵⁾

Arthur Kornberg, who became a distinguished biochemist and molecular biologist, attended van Niel's course to further his development as a researcher. Originally trained as a physician, Kornberg had become a research biochemist by "metamorphosis." In 1953, his research career was well underway. Nonetheless, he chose to prepare for his position as chairman of the new Department of Microbiology at Washington University Medical School with a summer with van Niel in 1953. He had become convinced "that instruction of medical students in the basic biochemistry and genetics of bacteria, viruses and parasites would be more valuable than exclusive attention to the latest techniques in culturing and staining each of the many pathogenic microbes."⁽¹²⁶⁾ For formal training in general microbiology, he naturally turned to van Niel's course, the best possible place. "Van Niel's course provided a superb historical review of microbiology and a powerful antidote to medically oriented bacteriology," Kornberg found, "He dwelled on the good microbes in the environment and forbade mention of the pathogens, except those few that had figured prominently in the history of microbes."⁽¹²⁷⁾ Kornberg's studies in the late 1950's on the enzymes involved in DNA replication won him a Nobel Prize in 1959.

Kornberg's colleague at Washington University Medical School, Paul Berg, took van Niel's course in 1954. Again it provided a counterbalance to the way bacteriology was taught in medical training. Berg took up research on the enzymes and other molecules involved in protein synthesis. He, too, became a prominent molecular biologist and went on to win the Nobel Prize in 1980.

Even apart from its practical and intellectual value, van Niel's course became a desirable social credential, as it became part of the common experience of an elite group of researchers. Acceptance into van Niel's class marked a scientist as a member of a select group. Gunther Stent, an influential molecular biologist at Berkeley, made the point bluntly. He said he applied to van Niel's course in 1950 because, "It was a legitimating paper, a feather in your cap, and I wanted it. You were nobody if you weren't in van Niel's course."⁽¹²⁸⁾ At the time, Stent was a postdoctoral fellow in Delbrück's laboratory, along with his close friends Seymour Benzer and Eli Wollman, a well-known researcher from the Pasteur Institute. In 1950, van Niel rejected Stent's application, while accepting Benzer and Wollmann, who both attended the microbiology course. This affront aggravated a festering animosity between Stent and van Niel that never subsided. Stent makes no mention of van Niel's course in his influential contributions to the history of molecular biology. In fact, eight of the thirty-two contributors to Phage and the Origins of Molecular Biology, including the celebrant himself, were participants in van Niel's course. Stent has said that he maintained tight editorial control of the submissions to this book.⁽¹²⁹⁾ Van Niel's name does not appear anywhere in this volume.

Two prominent members of the class of 1951 were Seymour Lederberg, a geneticist and the brother of Joshua Lederberg, and Lawrence Bogorad, a plant physiologist on the faculty at Harvard.

To students already committed to general microbiology, van Niel preached to the converted. Nonetheless, these students often derived new insights from the course. Ralph S. Wolfe, who received a Ph.D. in microbiology in 1953 from the University of Pennsylvania, joined the Department of Bacteriology at the University of Illinois, then distinguished by the presence of Harlyn O. Halvorson, Gunsalus, Luria, and Spiegelman. Van Niel accepted Wolfe as an auditor for the summer course in 1954. "The class was a fantastic experience that opened my eyes to a microbial world of unfamiliar organisms," Wolfe wrote later, "I returned to Illinois with many ideas from van Niel that, together with some from Gunny, Luria, Sherman, and myself, became an organisms course that would be taught for nearly three decades."⁽¹³⁰⁾

Not every scientist was deeply moved intellectually by van Niel's course. For Berkeley molecular biologist Bruce Ames, the course was not a profoundly transforming experience. "I remember a pleasant summer and made some good friends," he recalled, "It didn't make a big impact on you." At the same time, Ames called it "a great course," and said, "The people were interesting."⁽¹³¹⁾

In the 1940's and 1950's, van Niel's knowledge of the microbial world was probably unsurpassed in the world. His course provided a unique opportunity to learn both the substantive content of microbiology and practical techniques and methods. In the 1940's and 1950's, van Niel retained the basic set of topics and framework he had established before the war. Although the substantive content of the lectures changed over time, its structure, underlying philosophy, principles of organization, and purpose did not. Van Niel systematically incorporated new material into this framework. Every summer, he wrote his lectures anew by hand. The lectures became more refined and elegant with each passing year. The course could be viewed as a kind of performance art.

After his sabbatical at Caltech in 1946 and the disruptions of the war years, van Niel was happy to return to teaching his summer course. "Course given for my pleasure," he wrote in his lecture notes in 1947, "if it pleases others there is a common meeting ground. I do not require anyone to learn anything in particular." As in the 1930's, van Niel stressed that microorganisms were valuable to study because they revealed the fundamental features of life most clearly. At the same time, he cautioned his students against making naive generalizations. "Obviously, not all life processes can be studied with microbes," he noted, "An extrapolation though possible, often dangerous."⁽¹³²⁾

Van Niel continued to present science as a philosophical quest. Van Niel's discussion of experimentation addressed the major elements of his philosophy of science. "Why do an experiment?" he would ask. Logically enough, "to get an answer to a question," was the purpose. Then van Niel would ask, "What sort of answer?" Van Niel held that experiments simply indicate "That something is more probable than something else," rather than produce certain knowledge.⁽¹³³⁾ He adopted the view of the French philosopher of science Henri Poincaré that experiments were means for eliminating alternative hypotheses, not for establishing incontrovertible truth. He continued to emphasize the importance of principles over isolated facts. His notes state, "Answers may remain isolated and then not profound," and "Knowledge of facts always limited so hypoth [sic] tentative."⁽¹³⁴⁾ Van Niel continued to draw a picture of scientific knowledge as transitory, tentative, and changeable, rather than certain, absolute, and incontrovertible.

As the course developed from 1947 to 1954, van Niel included more organisms and more metabolic pathways as these became elucidated by ongoing research. He conveyed no sense that a revolution was underway in biology. He integrated the new information into the framework he had defined in the 1930's. As a consequence, he made no attempt to cover the new areas of microbial and phage genetics. He included only the basics of yeast genetics as he had taught it in the past. Rather, the information he provided on microorganisms and the diversity of their metabolic pathways could be used by students of genetics.

Beginning in 1948, van Niel gave special attention to the importance of eschewing reductionism for understanding living phenomena. He advised his students to accept the concept of "integrative levels," as introduced by physiologist Alex B. Novikoff in 1945. Attempting a grand theory of the organization of matter in the cosmos, Novikoff wrote:

Each level of organization possesses unique properties of structure and behavior which, though dependent on the properties of the constituent elements, appear only when these elements are combined in the new system. Knowledge of the laws of the lower level is necessary for a full understanding of the higher level; yet the unique properties of phenomena at the higher level can not be predicted, a priori, from the laws of the lower level.⁽¹³⁵⁾ For van Niel, this principle was an important validation for studying the microorganism as a whole. Van Niel studied the biochemical activities of microorganisms in order to understand their physiology.

Van Niel appreciated Novikoff's views because they seemed to offer a way to escape a mechanistic approach without resorting to vitalism. In Novikoff's words:

The concept of integrative levels recognizes as equally essential for the purpose of scientific analysis both the isolation of parts of a whole and their integration into the structure of the whole. It neither reduces phenomena of a higher level to those of lower one, as in mechanism, nor describes the higher level in vague non-material terms which are but substitutes for understanding, as in vitalism.⁽¹³⁶⁾ In the decade after World War II, van Niel's course served as a crucial resource for the transmission of the basic craft and substantive content of microbiology to an elite group of researchers. It combined practical instruction, acculturation, recreation, and social legitimation. Germaine Cohen-Bazire, who took the course in 1954, spoke for many graduates of van Niel's course when she said: "It's the greatest course in the world."⁽¹³⁷⁾

E. Making Microbiological History -- Reinventing the "Delft School"

In the postwar decade, several fields, including general microbiology, made bids to achieve disciplinary status. The resourceful exploitation of new and old sources of funding in combination with new opportunities in research universities provided inviting conditions for attempts to establish new or build old disciplines. Microbiology contended with older established fields like biochemistry, genetics, and physiology and with newcomers like biophysics for departmental status, positions, funding, laboratory space and the allegiance of practitioners.⁽¹³⁸⁾ General microbiology developed within this dynamic context.

In the 1940's and 1950's, new societies, journals, and university departments devoted to microbiology were established in the United States and internationally.⁽¹³⁹⁾ The Society for General Microbiology was founded in Great Britain in 1946. Soon thereafter, it began publishing the Journal of General Microbiology. The Canadian Society of Microbiologists began producing its own journal of microbiology in 1954. In the United States, a group of leading microbiologists founded the journal Annual Review of Microbiology in 1947. Modeled on the very successful Annual Review of Biochemistry, founded in 1932, the new journal was intended to provide critical reviews of active areas of research. It was necessary because of the new importance of microbiological research. "With the rapidly expanding interest in the study of microorganisms there has been an increase in the literature of microbiology to such an extent that no one can hope to keep abreast of the advances in the various fields," said the announcement for the journal's first volume.⁽¹⁴⁰⁾ Van Niel agreed to serve on the first board of editors.⁽¹⁴¹⁾ Just after the end of the second world war, the membership of the SAB increased in number at the highest rate in its history, with a doubling time of about six years.⁽¹⁴²⁾

In the public eye, the practical achievements of microbiology always overshadowed the theoretical. Public acclaim for the development of antibiotics was inevitable; it sometimes approached the hysterical.⁽¹⁴³⁾ In 1949, for example, an image of Waksman graced the cover of the popular magazine Time. The scientist was depicted gazing intently at a giant floating test tube. Inside, his research on antibiotics was lauded in the article "Drugs versus Bugs."⁽¹⁴⁴⁾ Three years later, Waksman was awarded the Nobel Prize for his research on streptomycin, the first antibiotic effective against tuberculosis.

Within the SAB, however, general microbiology increased in prominence and prestige during the 1940's and 1950's. By the time the SAB celebrated its fiftieth anniversary in 1949, general microbiology had won a substantial presence in the Society's affairs. In the commemorative volume for the occasion, the Secretary of the SAB, microbiologist Barnett Cohen, wrote with approval, "Now after the lapse of a half-century it may be fairly stated that the range of our interest is as much in the field of general microbiology as it is in bacteriology narrowly conceived."⁽¹⁴⁵⁾ The shift in research interests of the members of the SAB is quantifiable. From 1935 to 1942, the number of papers on applied topics at the SAB annual meeting outnumbered those on general microbiology by a margin of two to one. By 1949, the ratio was about one to one. Two years later, the number of papers on general and physiological topics exceeded by about twenty per cent the number on medical, industrial, and agricultural topics combined.⁽¹⁴⁶⁾

As general microbiology rose in prominence and importance in the postwar decade, it became important for its leaders to lay out an appropriate history. As historian and philosopher of science Thomas Kuhn and others have pointed out, the production of historical accounts is an important aspect of discipline formation.⁽¹⁴⁷⁾ This process is an example of what anthropologists have called the construction of "origin myths."⁽¹⁴⁸⁾

Van Niel was very aware of the rising prominence of microbiology in the 1940's and 1950's. He was also aware that certain kinds of scientific contributions could be absorbed into the fabric of research without much acknowledgment. In the 1940's and 1950's, van Niel began to make efforts to secure recognition for the contributions of his scientific predecessors at the Laboratory for Microbiology at Delft.

In 1949, the SAB recognized the ascendance of general microbiology by electing Kluyver as an honorary foreign member. As Kluyver's heir-apparent, van Niel was invited to give the testimonial lecture at the annual meeting. The occasion gave van Niel an ideal opportunity to celebrate the recent expansion in microbiology and to promote his conception of microbiology as a form of philosophical inquiry. It also provided an opportunity to define an important place in the recent history of microbiology for his mentors in Delft, Kluyver and Beijerinck, and by implication, for himself. In the process, van Niel redefined the "Delft School" to serve as an appropriate source for the kind of microbiology he espoused and practiced. In van Niel's depiction, the "Delft School" referred to a tradition of research exclusively interested in general microbiology as a theoretical science. He gave credit to the perspectives and practices of his mentors at Delft for stimulating the recent expansion in general microbiology.

To introduce his lecture, van Niel spoke briefly about Antony van Leeuwenhoek, the seventeenth century figure who first observed the microscopic organisms later recognized as bacteria. By a happy coincidence, van Leeuwenhoek had been a citizen of Delft. Van Niel paid him brief homage, but recognized Beijerinck as the real founder of the "Delft School." Van Niel emphasized the importance of Beijerinck's explorations of the diversity of the microbial world through the artful use of the elective culture technique for isolating microorganisms. This technique had provided a model for the logic and method of selecting for nutritional mutants, a process essential to the practice of microbial genetics. As the technique became incorporated into the standard practice of microbial geneticists, van Niel feared that its historical origins would become lost from view. He wanted Beijerinck to receive recognition for developing the method. "Even such up-to-date studies as those concerned with the search for antibiotics...and with the selection of specific nutritional types of microbes; all such studies are now carried out with the conscious or unconscious inclusion of Beijerinck's principles."⁽¹⁴⁹⁾ Van Niel followed Kluyver's lead in portraying Beijerinck as a great nineteenth century founder of microbiology on the level of Louis Pasteur and Robert Koch.⁽¹⁵⁰⁾

Van Niel devoted the core of his lecture to Kluyver. He especially sought to give credit to Kluyver for articulating the powerful concept of "the unity in biochemistry." Van Niel admitted that this principle was not a unique contribution of Kluyver. However, van Niel maintained that his mentor in Delft had made the most comprehensive statement of this principle. Further, according to van Niel, Kluyver's commitment to this principle had exerted a great influence on research in microbial metabolism. Van Niel left unstated the important point, obvious to his audience, that his own research on photosynthesis in bacteria had been directly stimulated by Kluyver's concepts. He noted that Kluyver was the first to use the phrase "comparative biochemistry."⁽¹⁵¹⁾

Van Niel's lecture made clear that he considered recent work on the genetics of microorganisms to be an important sub-field of microbiology. Because of his own broad conception of general microbiology, van Niel could legitimately claim that any study of the basic biology of microorganisms properly belonged to this field. Van Niel saw the new research on the genetics of microorganisms as evidence of the vitality and importance of general microbiology. He noted proudly, "Nearly all studies in this field of physiological or biochemical genetics are carried out with microbes, and most of these investigations are patterned on the important work of Beadle and Tatum and their collaborators."⁽¹⁵²⁾

To link these studies to the "Delft School," van Niel cheerfully cited work by Beijerinck that had been dismissed as unimportant, or even disreputable by Kluyver.⁽¹⁵³⁾ Van Niel even went so far as to suggest that the one gene/one enzyme principle had been anticipated by Beijerinck. "The numerous contributions, in which algae, molds, yeasts, protozoa, bacteria, and phage play so important a part," said van Niel, "supports an idea expressed as early as 1917 by Beijerinck, namely, that genetic characters function by way of controlling the formation of enzymes."⁽¹⁵⁴⁾

In general, van Niel emphasized the theoretical works of Beijerinck and Kluyver, while omitting any mention of any of their practical studies. He refrained from mentioning Kluyver's development of the submerged culture technique for growing molds, an innovation that played a major role in the industrial production of penicillin. He also neglected to name the institution where both microbiologists had worked, and where van Niel had studied. This omission allowed van Niel to avoid the words "chemical engineering" and "technical university." Honoring Kluyver, he emphasized, "bears convincing witness to the fact that our Society of American Bacteriologists is concerned with broad principles."⁽¹⁵⁵⁾ Further distancing microbiology from concrete practice, van Niel went on to say, "The work of the 'Delft School' carries implications of deep philosophical importance that must appeal to any one who is willing to subscribe to Ernest Renan's dictum: 'Le but du monde, c'est l'Idée.'"⁽¹⁵⁶⁾ The disembodied "Delft School" remained as abstract and ethereal as the science it was supposed to represent.

Van Niel took the defense of his conception of general microbiology to extremes. He brought up the subject of applied research only to lament its overemphasis. Van Niel worried that some of the new interest in microbiology "could have been stirred up by an overemphasis on developments of the past decade resulting from vitamins, chemotherapy, and antibiotics."⁽¹⁵⁷⁾ At the same time, he carefully included this research within his discipline by saying, "these topics represent only a small segment of the field of general microbiology."⁽¹⁵⁸⁾

Van Niel's lecture expressed his belief that the development of science, the course of individual lives, and even the history of humanity were all interrelated reflections of one another. The proper and natural development of each was supposed to occur through the gradual increase in rationality. The steps along the way were provisional. Finality in scientific knowledge and human evolution was a distant goal. In a resounding finale, van Niel asked his audience,

...to consider seriously the proposition that an important aspect of evolution consists in the acquisition of increased comprehension. Comprehension not for the sake of power -- there is too much of that in the hands of too few -- but for the sake of a possible evolution of man to a state in which he is no longer at war with himself and his contemporaries, no longer at odds with nature, but an integral part of it. The implication of this is the need for the recognition of the intrinsic value of the individual as the unique, potential step towards something new and better.⁽¹⁵⁹⁾ In the 1950's, van Niel continued his attempt to win recognition of the "Delft School" through private correspondence as well as in public lectures. In 1950, he wrote to H.O. Halvorson, professor of microbiology at the University of Illinois, to congratulate him on the appointment of I.C. Gunsalus to the department there. Van Niel's letter read like an advertisement for the "Delft School" and general microbiology in general:

The contributions made by the Delft laboratory are gradually getting the recognition they deserve....They comprise most aspects of culture, physiology, and biochemistry of microorganisms, from algae and fungi through protozoa and bacteria to the viruses. And what has grown out of it is so exciting that it is also understandable, not merely heartening, that interest in the field has developed so rapidly during the past ten years.⁽¹⁶⁰⁾Van Niel went on to review the many important research advances made through the study of microorganisms. "Where would 'biochemical genetics' be if had not started with studies on microorganisms?" he asked rhetorically. Spiegelman, a member of the Illinois microbiology faculty, apparently read the letter, too. He wrote to Stanier, "Halvorson received a typical van Nielian letter congratulating him on what he is building up here and at the same time tracing the history of microbiology, its concepts and future. It was wonderful."⁽¹⁶¹⁾

Van Niel's efforts to secure recognition of the "Delft School" may be judged a partial success. In 1951, a RF report announcing a grant of $10,000 to van Niel described microbiology in terms very reminiscent of van Niel's lecture on the "Delft School."⁽¹⁶²⁾ Similarly, Stuart Mudd, a leading microbiologist at the University of Pennsylvania, followed van Niel's lead in his introduction to a symposium on bacterial cytology at the Sixth International Congress of Microbiology in Rome in 1953. Mudd chose to cite two examples of prominent leaders who had cultivated the study of the physiology and ecology of microorganisms: M.W. Beijerinck and A.J. Kluyver. "Kluyver's survey of microbial metabolism," said Mudd, "led to the broadest possible generalization of Lavoisier's concept of biological oxidations." Like van Niel, he remarked that Kluyver was the first to use the phrase "comparative biochemistry."⁽¹⁶³⁾

Among microbiologists, the "Delft School" remains a highly esteemed tradition.⁽¹⁶⁴⁾ What van Niel did not (and could not) perceive was that accounts of the origins of molecular biology generated in the 1960's and 1970's would obscure the importance of general microbiology in the 1940's and 1950's. During these decades, however, van Niel and the associates of the "Delft School" were widely perceived as the world leaders in the field of general microbiology, and general microbiology was recognized as a leading field.

In 1953, at the height of general microbiology's importance, van Niel was elected president of the SAB. A controversy over plans for the 1956 annual meeting, scheduled to be held in Houston, required his attention.⁽¹⁶⁵⁾ At the time, segregationist ordinances in Texas made it illegal for African-American scientists to stay in the "whites only" hotel where the conference would be held.⁽¹⁶⁶⁾ According to arrangements made by the local planning committee, black scientists would be admitted only to the annex section of the hotel where the sessions would be held. Stanier and Doudoroff organized a protest.⁽¹⁶⁷⁾ Van Niel was caught between his desire to avoid controversy and his sympathy for the viewpoint of Stanier and Doudoroff.⁽¹⁶⁸⁾ Ultimately, van Niel sided with those who believed that the arrangements provided for African-American members to attend the official events of the meeting would be adequate.⁽¹⁶⁹⁾ The 1956 meeting of the SAB was held in Houston.

In the 1950's, honors continued to rain on van Niel, the "Delft School," and general microbiology. In 1954, Waksman invited the luminaries in microbiology and microbial genetics to Rutgers to attend the dedication of a brand new Institute for Microbiology financed by royalties from streptomycin. Along with Kluyver, who gave the opening addresse, van Niel and Horace Barker represented the "Delft School." Bernard Davis and Joshua Lederberg represented microbial genetics, as did Lwoff from the Pasteur Institute.⁽¹⁷⁰⁾

In April of 1954, van Niel and Kluyver were invited jointly to give the prestigious Prather Lectures at Harvard. Organized by the plant physiologist Kenneth Thimann, the lectures gave van Niel and Kluyver the opportunity to survey for a broad academic audience the important advances in microbiology. The two scientists looked forward to the reunion with great anticipation, as they had not seen each other since 1936. The title for their lectures, "The Microbe's Contribution to Biology," expressed concisely the ambition of the "Delft School" microbiologists to make microbiology an integral part of biology. Kluyver gave two lectures on microbial metabolism, the first on the energetic basis of life, the second on the unity of life on the biochemical level. Van Niel then discussed phototropic bacteria as the "Key to the Understanding of Green-plant Photosynthesis." Kluyver then took up the subject "Microbial Adaptations," in which he emphasized the flexibility and adaptability of living things to changing environmental conditions. Van Niel continued that theme in his discussion of "Microbial Mutations." He completed the series with a lecture on "Evolution as Viewed by the Microbiologist." Their lectures illustrated how incomplete and distorted biological knowledge would be if it failed to include the nature and activities of microorganisms.⁽¹⁷¹⁾

Shortly thereafter, van Niel set sail for Europe for his second sabbatical. He planned to visit dozens of laboratories in Europe and in Israel. At the time, he had much to celebrate. In 1954, van Niel, general microbiology, the "Delft School," and the microbe itself were major features on the landscape of the life sciences.

F. Microbiology and Microbial Genetics

As van Niel readily acknowledged, the new dynamism in microbiology in the postwar period derived in part from research in microbial genetics. An emerging research specialty in the 1940's, microbial genetics served as an important antecedent to molecular biology as constituted in the 1960's and 1970's. The evidence I give here shows that microbial genetics existed for about fifteen years prior to molecular genetics, which developed rapidly after 1953. Between 1940 and about 1955, microbial genetics was as tightly linked to general microbiology as to genetics. Microbiology provided social, institutional, intellectual, and technical support for research in microbial genetics.

Microbiology provided organisms, techniques and an organized body of knowledge about microbial physiology that was essential for research on microbial genetics. The problem of adaptive enzymes, which later proved crucial to the analysis of gene regulation, derived from classical bacterial physiology. Many of the most useful mutations in bacteria caused blocks of various kinds in biochemical pathways. These would have been incomprehensible without the knowledge of the biochemical pathways in the first place. As we have seen, van Niel's course provided a specific opportunity for the transfer of the methods, organisms, and substantive content of general microbiology to an important group of researchers.

Until the mid-1950's, leading practitioners associated microbial genetics as closely with microbiology as with genetics. In 1951, Lederberg, one of the leaders in the field, assembled a set of recent research papers on bacterial and viral genetics into a volume to be used for teaching. He included papers by Luria and Delbrück on bacterial mutations, two of his own articles on genetic recombination in bacteria, and work by Demerec and Davis on the use of penicillin for selecting bacterial mutants. The concluding sentences of Lederberg's introduction indicate the close connection he perceived between genetics and microbiology: "Genetic study of bacteria and viruses is closely interwoven with the most general problems of their biology....it is to be hoped that genetics will be regarded not as a unique or isolated part of bacteriological study, but as an element of all teaching and research in microbiology.⁽¹⁷²⁾

The technical contributions of microbiology to microbial genetics may be too pervasive and diffuse to be described as identifiable units. However, one microbiological technique deserves particular mention, namely the elective culture technique practiced by Beijerinck and taught by van Niel. Researchers in bacterial genetics adapted this technique for use in the selection of artificially produced mutations, rather than naturally occurring varieties. After this approach became integrated into the general practice of microbial geneticists, its source was no longer acknowledged. In 1954, Lederberg recognized the source of this technique in his lecture "Genetics and Microbiology," given at the opening of Waksman's Institute. In his talk, Lederberg reviewed the evidence for genetic recombination in bacteria and reconsidered the origins of mutations in bacteria. He then pointed out:

There has been exaggerated overemphasis on the technology of provoking genetic variation (which is relentless anyhow) at the expense of thoughtful search for procedures to detect and electively enrich the variants that serve some specific purpose, an approach we have inherited in large part from the Delft school of microbiology.⁽¹⁷³⁾ An institutional and organizational infrastructure of microbiology already existed in the 1940's. This meant that departments, congresses, societies, and journals of microbiology could provide a basis for a new research specialty like microbial genetics. Some researchers in microbial genetics found institutional homes in genetics departments as at the University of Wisconsin or general biology departments as at Caltech. Microbiology departments also provided institutional locations for research in microbial genetics. Many researchers who later became identified as molecular biologists found employment in microbiology or bacteriology departments in either universities or medical schools in the 1940's and 1950's. Microbiology departments at the University of Illinois, Indiana University, and Berkeley became especially important centers for research in microbial genetics and general microbiology. Salvador Luria held appointments in the bacteriology departments at Indiana and Illinois. Sol Spiegelman held appointments in Bacteriology at Washington University School of Medicine from 1945 to 1948, then at the University of Illinois Department of Microbiology from 1946 to 1969. Even arch-molecular biologist Gunther Stent held either part or full-time appointments in Berkeley's bacteriology department from 1952 until 1963. Arthur Kornberg was a Professor of Microbiology at Washington University School of Medicine from 1953 to 1959. Bernard Davis served as professor Bacteriology and Immunology at New York University's College of Medicine from 1957 to 1968. He then became Professor of Bacterial Physiology at Harvard University Medical School.

Congresses of microbiology were important locations for researchers in microbial genetics to meet. The Fourth International Congress of Microbiology in 1947 in Copenhagen, for example, was an important meeting for the formation of the new specialty in microbial genetics. Francois Jacob, who became an important member of the group of researchers at the Pasteur Institute, became interested in microbial physiology by attending this meeting.⁽¹⁷⁴⁾ The annual meetings of the Society for General Microbiology held in England provided important opportunities for interactions among researchers working on microbial genetics in Europe. In 1952, for example, Benzer and Stent, then working at the Pasteur Institute, joined Monod and Lwoff in attending the meeting of the Society for General Microbiology. There, they heard Watson report on recent experiments by Alfred Hershey and Martha Chase, which showed that only the DNA component of bacteriophage and not the protein entered into a bacterial cell upon infection. At the same meeting, they heard about experiments on bacterial mating carried out by William Hayes, working independently in a London hospital. Hayes found that the transfer of genetic markers in bacteria was directional, implying that some bacteria were capable of acting as donors whereas others acted as recipients. He interpreted this as a kind of sexual differentiation in bacteria.⁽¹⁷⁵⁾

Microbiologists also made important theoretical contributions to interpretations of microbial heredity that became incorporated into molecular biology. Researchers at the Pasteur Institute played a key role in developing many of the central concepts of molecular biology. Most of these were carried out under Lwoff's direction within the Service de Physiologie Microbienne, equivalent to a department of Microbial Physiology. Van Niel and Stanier paid close attention to developments in microbial genetics throughout the 1940's and 1950's and worked to integrate the new research into a broad framework of microbiology. Through his involvement in developing new terminology, Stanier played an important role in advancing new conceptions of bacterial heredity.

In the middle of the 1950's, the disciplinary relations of microbiology and molecular biology were very different than they were one or two decades later. In 1955, microbiology was institutionally secure whereas molecular biology was not. In 1955, John R. Raper, professor of biology at Harvard University, asked Stanier to assess the potential of J.D. Watson to be a productive scientist.⁽¹⁷⁶⁾ This was two years after Watson and Francis Crick had proposed a structure for DNA. Stanier responded that he judged Watson to be a "creative scientist of the first magnitude." Among American scientists, only Lederberg was in the same class, thought Stanier. It seemed obvious to Stanier that scientists of this caliber should be provided with whatever they needed to conduct their work. Stanier saw institutional obstacles to this in the case of Watson because he did not fit into "any of the conventional ecological niches." Stanier and his colleague Daniel Mazia had wanted to bring Watson to Berkeley. Departmental identities were too well-fixed to accommodate the kind of research represented by Watson. "We eventually concluded that in our narrowly departmentalized university, he just couldn't be fitted into any of the various Procrustean beds available....A majority of my bacteriological colleagues would probably look askance at his qualifications; and he doesn't even belong in biochemistry as this is conventionally construed." Stanier concluded that only a broadly defined biology department like the one at Harvard could comfortably provide an institutional home for Watson.⁽¹⁷⁷⁾ Watson joined the Harvard Department of Biology soon thereafter.

The significant interconnections between microbiology and molecular biology have been obscured by the way the history of molecular biology has been written. Practitioners and historians have emphasized the role of genetics, biochemistry, physical chemistry, and physics in creating the body of knowledge that became the core of molecular biology. The connections between microbiology and molecular biology are especially interesting because they have been overlooked or treated as unproblematic.⁽¹⁷⁸⁾ One difficulty has been the tendency by historians to equate molecular genetics and microbial genetics. In the late 1950's, molecular genetics rapidly replaced microbial genetics as the leading research frontier. Its tremendous success caused many practitioners and most historians of science to lose sight of the importance of microbial genetics in the previous decade.

Between 1945 and 1955, general microbiology enjoyed a distinct period of prominence, expansion, and productivity. Van Niel's ambition to establish microbiology as a general science of life appeared eminently successful during this decade. The general postwar expansion in science, the development of antibiotics during the war, new conceptions of bacterial heredity, and the teaching and research of scientists like van Niel created conditions that stimulated the increase in interests in microorganisms. Van Niel and his students encouraged the new enthusiasm for microbiology and acquired the most important kind of capital in their social and intellectual milieu, scientific authority.⁽¹⁷⁹⁾

Index | Previous | Next

1. C.B. van Niel, "The 'Delft School' and the Rise of General Microbiology," Bacteriological Reviews, 13 (1949), pp. 161-74 on p. 171.

2. Horace Freeland Judson, The Eighth Day of Creation: Makers of the Revolution in Biology (New York, Simon & Schuster, 1979); Donald Fleming,"Emigré Physicists and the Biological Revolution," Perspectives in American History 2, (1968), 152-189; Evelyn Fox Keller, A Feeling for the Organism (New York: W.H. Freeman, 1983), p. 153.

3. The nature and purpose of retrospective accounts, origin myths, and legitimating histories has been discussed in a range of fields. For molecular biology see especially Pnina Abir-Am, "Themes, Genres and Orders of Legitimation in the Consolidation of New Scientific Disciplines: Deconstructing the History of Molecular Biology," History of Science, 23 (1985), 74-117, and idem., "How Scientists View their Heroes: Some Remarks on the Mechanism of Myth Construction," Journal of the History of Biology, 15 (1982), 281-316. For analysis of an episode of constructing a "founder" closely connected to this study, see Bert Theunissen, "Martinus Willem Beijerinck and the 'Delft' Tradition in Microbiology," in Piet Bos and Bert Theunissen, eds., Beijerinck and the Delft School of Microbiology (Delft: Delft University Press, 1995), 183-192.

4. Warren Weaver, director of the Natural Sciences division of the Rockefeller Foundation created the term in 1938. Warren Weaver, "Molecular Biology: Origins of the Term," Science, 170 (1970), pp. 591-92.

5. Van Niel to Kluyver, May 27, 1945; AJK.

6. Kluyver to van Niel, August 21, 1945; AJK.

7. Van Niel to Stanier, September 30, 1945; RYS 6/21.

8. Carl Robinow to Stanier, August 10, 1946; RYS 6/12.

9. Van Niel to Donald B. Tressider, March 22, 1944; RLW 128/Hopkins Marine Station.

10. This was the Sterling Professorship. G. Pomerat, Diary, January 20,1948; RF1.2; 205D, 6/42; RAC.

11. "Trustees Confidential Report," March 1956; RF RG 1.2, 205D, 6/43; RAC. Van Niel to Stanier, January 30, 1945; RYS 6/21.

12. Van Niel to Stanier, September 30, 1945; RYS 6/21.

13. Van Niel to Stanier, n.d., 1946 by inference; RYS 6/21.

14. Doudoroff to Stanier, May 10, 1945; RYS 5/11.

15. Thomas D. Brock, The Emergence of Bacterial Genetics (Cold Spring Harbor: Cold Spring Harbor Laboratory Press, 1990), p. 21; M. Demerec, "Origin of Bacterial Resistance to Antibiotics," Journal of Bacteriology, 56 (1948), 63-74.

16. Marjory Stephenson, Bacterial Metabolism (London: Longmans, Green, and Co., 1930), p. viii.

17. See, e.g., the irritation of microbiologist René J. Dubos at this expression, The Bacterial Cell (Cambridge: Harvard University Press, 1945), p. 3.

18. S.E. Luria and M. Delbrück, "Mutations of Bacteria from Virus Sensitivity to Virus Resistance," Genetics, 28 (1943), 491-511.

19. Delbrück to Stanier, August 14, 1943; 5/10 RYS. In 1927, the American bacteriologist Philip Hadley had argued that variation in bacteria reflected different stages in their complex life-cycles. See Olga Amsterdamska, "Stabilizing Instability: The Controversy over Cyclogenic Theories of Bacterial Variation During the Interwar Period," Journal of the History of Biology, 24 (1991), 191-222.

20. Gunther S. Stent, Molecular Biology of Bacterial Viruses (San Francisco: W.H. Freeman, 1963), p. 39.

21. See Evelyn Fox Keller, "Between Language and Science: The Question of Directed Mutation in Molecular Genetics," in Secrets of Life, Secrets of Death: Essays on Language, Gender, and Science (New York: Routledge, 1992) 161-178, for discussion of the historical significance of this paper and of recent scientific challenges to the validity of its conclusions.

22. A.D. Hershey, "Spontaneous Mutations in Bacterial Viruses," Cold Spring Harbor Symposia on Quantitative Biology, 11 (1946), 67-76.

23. S.E. Luria and M. Delbrück, "Mutations of Bacteria from Virus Sensitivity to Virus Resistance," Genetics, 28 (1943), 491-511.

24. René J. Dubos, The Professor, the Institute, and DNA (New York: The Rockefeller University Press, 1976), 132-159.

25. Oswald T. Avery, Colin M. MacLeod, and Maclyn McCarty, "Studies on the Chemical Nature of the Substance Inducing Transformation of Pneumococcal Types," The Journal of Experimental Medicine, 79 (1944), 137-158.

26. See, e.g., Judson, Eighth Day of Creation (1979), 36-41 and the general characterization of biologists, including Avery, in Fleming, "Physicists and the Biological Revolution," (1968).

27. J. Lederberg and E.L. Tatum, "Novel Genotypes in Mixed Cultures of Biochemical Mutants of Bacteria,' Cold Spring Harbor Symposia on Quantitative Biology, 11 (1946), 113-114.

28. E.L. Tatum, "X-ray Induced Mutant Strains of E. coli," Proceedings of the National Academy of Science, U.S.A. 13 (1945), 215-219.

29. Joshua Lederberg, "Genetic Recombination in Bacteria: A Discovery Account," Annual Reviews of Genetics, 21 (1987), 23-46.

30. Beadle to Tatum, September 9, 1946; GB 7/24.

31. Tatum to Beadle October 15, 1946; GB 7/24.

32. S.E. Luria, "Recent Advances in Bacterial Genetics," Bacteriological Reviews, 11 (1947), 1-40.

33. See Jan Sapp, Beyond the Gene: Cytoplasmic Inheritance and the Struggle for Authority in Genetics (New York: Oxford University Press, 1983) for comprehensive discussions of research on cytoplasmic heredity.

34. Gunther S. Stent, Molecular Genetics An Introductory Narrative (San Francisco: W.H. Freeman and Company, 1971), p. 133.

35. C.B. van Niel, "The Classification and Natural Relationships of Bacteria," Cold Spring Harbor Symposia on Quantitative Biology, 11 (1946), 285-301.

36. Van Niel to Stanier, January 5, 1944; RYS 6/21.

37. Van Niel to Stanier, n.d. 1946 by inference; RYS 6/21.

38. See Lily E. Kay, The Molecular Vision of Life: Caltech, The Rockefeller Foundation and the Rise of the New Biology (New York: Oxford University Press, 1993) for a detailed study of this project.

39. Beadle to Pauling, February 27, 1946; Division of Chemistry, 1/2; CIT.

40. Beadle to Pauling February 27, 1946; Division of Chemistry, 1/2; CIT. Tracy Sonneborn, the specialist in the genetics of protozoans, was also listed as a potential faculty member.

41. Van Niel to Stanier, November 11, 1946; RYS 6/21.

42. Van Niel to Stanier, April 25, 1945; RYS 6/21.

43. Van Niel to Stanier, February 16, 1947; RYS 6/21.

44. Postdoctoral fellows who stayed for one year or less included S.R. Eldsen, Benjamin Volcani, G. Fahraeus, I. Tittler, Jane Pinsent, Arthur Schatz, and Raul Trucco. See C.B. van Niel, "Education of a Microbiologist: Some Reflections," Annual Review of Microbiology, 21 (1967), 1-30, on p. 25.

45. Van Niel, "Education," (1967), on 25. Postdoctoral fellows included Roderick K. Clayton, J. Silliker, Max Eisenberg, Helen Whitely, Alma Whiffen, Harry Katznelson, Adelaide Brokaw, Marian Kramer, Kjell and Kjellrun Baalsruud, M. Winfield, and W Verhoeven.

46. Representative publications from this period include M.B. Allen, "The Dynamic Nature of Thermophily," Journal of General Physiology, 33 (1950), 205-14; A. Schatz, "Growth and Hydrogenase Activity of a New Bacterium, Hydrogenomonas facilis," Journal of Bacteriology, 63 (1952), 87-98; Wolf Vishniac, "The Metabolism of Thiobacillus thioparus. I. The Oxidation of Thiosulfate," Journal of Bacteriology, 64 (1952), 363-75; Barbara E. Wright, "Auto-adapatation: A New Phenomenon Observed in a Bacterial Population," Journal of Bacteriology, 66 (1953), 407-22. See van Niel, "Education," (1967), p. 25 for a summary.

47. Stanier and Doudoroff, "Professor van Niel," (1967), p. 2.

48. Van Niel to Weaver, July 29, 1954; RF, RG 1.2, 205D, 6/43; RAC.

49. Helge Larsen, "On the Culture and General Physiology of the Green Sulfur Bacteria," Journal of Bacteriology, 64 (1952), 187-97.

50. Van Niel to Loomis, February 22, 1950; RF 1.2, 205D, 6/41; RAC. See also, H. Larsen, C. Youcm, and C.B. van Niel, "On the Energetics of the Photosyntheses in Green Sulfur Bacteria," Journal of General Physiology, 36 (1952), 161-71.

51. Van Niel to Stanier, November 11, 1946; RYS 6/21.

52. Van Niel to Stanier, March 11, 1944 (year by inference); RYS 6/21.

53. Van Niel to Stanier, October 7, 1947; RYS 6/21.

54. Van Niel to Weaver, June 14, 1948; RF 1.2, 205D, 6/42; RAC.

55. Van Niel to Weaver, March 11, 1948; RF 1.2, 205D, 6/42; RAC.

56. Van Niel to Weaver, March 11, 1948; RF 1.2, 205D, 6/42; RAC.

57. G.R. Pomerat Diary, January 16-20, 1948; RF 1.2, 205D, 6/42; RAC.

58. Van Niel to Weaver, March 31, 1948; RF 1.2, 205D, 6/42; RAC.

59. Resolution 48214; RF 1.2, 205D, 6/42; RAC.

60. Resolution 51249; RF 1.2, 205D, 6/42; RAC.

61. Resolution 51076, RF 1.2, 205D 6/42; RAC.

62. Van Niel to Weaver, July 29, 1954; RF 1.2, 205D, 6/43; RAC.

63. Roger Y. Stanier, "The Journey, Not the Arrival, Matters," Annual Review of Microbiology, 34 (1980), 11-12.

64. Angela N.H. Creager, "Wendell Stanley's Dream of a Free-Standing Biochemistry Department at the University of California, Berkeley," Journal of the History of Biology, 29 (1996), 331-360 on 339.

65. Doudoroff to Stanier, April 26, 1946; RYS 5/11.

66. Doudoroff to Stanier, April 26, 1946; RYS 5/11.

67. Van Niel to Stanier, February 16, 1947; RYS 6/21.

68. Van Niel to Stanier, March 30, 1947; RYS 6/21.

69. Van Niel to Stanier, February 2, 1947; 6/21 RYS.

70. See Creager, "Stanley's Dream of Free-Standing Biochemistry," (1996) for a detailed analysis of Stanley's controversial and partially successful attempts to reorganize biochemistry at Berkeley around TMV research.

71. See Sanford E. Elberg, "Graduate Education and Microbiology at U.C. Berkeley, 1930-1989," (Oral History Transcript; Bancroft Library, University of California, 1990), 64-84 for an account by one of the principal participants. For a description of tensions in the department in 1957, see Elberg to Lincoln Constance, June 10, 1957; UCBC 34/41.

72. Elberg to Constance, June 10, 1957; UCBC 34/41.

73. E.g., ibid.

74. See, e.g., Adelberg to Constance, June 28, 1957; UCBC 34/41.

75. See Elberg, "Microbiology at Berkeley," (1990), 84-101.

76. Stanier to Waksman, February 24, 1947; 6/23 RYS.

77. Doudoroff to Stanier, October 3, 1949 (year by inference); RYS 5/11.

78. Krueger to Doudoroff, July 22, 1949; RYS 5/11.

79. Stanier, "Journey," (1980), p. 15.

80. Stanier to Robert G. Sproul, May 9, 1950; RYS 6/14.

81. Henry P. Treffers to Barker, September 12, 1950; HAB 7/65.

82. Novick to Stanier, September 12, 1950; 6/2 RYS.

83. T.R. Hogness to Stanier, May 31, 1951; RYS 5/ "H-general, 1940-69."

84. See, e.g., R.Y. Stanier, "The Oxidation of Aromatic Compounds of Fluorescent Pseudomonads," Journal of Bacteriology, 55 (1948), 477; "Problems of Bacterial Oxidative Metabolism," Bacteriological Reviews, 14 (1950), 79-91; O. Hayaishi and R.Y. Stanier, "The Bacterial Oxidation of Tryptophan: A Study in Comparative Biochemistry," Science, 114 (1951), 326-330.

85. Howard K. Schachman, Arthur B. Pardee, and R.Y. Stanier, "Studies on the Macromolecular Organization of Microbial Cells," Archives for Biochemistry and Biophyics, 38 (1952), 245-60.

86. Stanier, "Bacterial Oxidative Metabolism," (1950), 179-191.

87. See, e.g., R.Y. Stanier, "Simultaneous Adaptation: A New Technique for the Study of Metabolic Pathways," Journal of Bacteriology, 54 (1947), 339-348; idem., "Enzymatic Adaptation in Bacteria,"Annual Review of Microbiology, 5 (1950), 35-56; idem., "Journey," (1980), 19-23.

88. Representative research articles include W.Z. Hassid, M. Doudoroff, and H. Barker, "Enzymatically synthesized disaccharides, Archives of Biochemistry, 14 (1947), 29-37; N. Entner and M. Doudoroff, "Glucose and Gluconic Acid Oxidation of Pseudomonas saccharophila," Journal of Biological Chemistry, 196, (1952), 153-163; J. MacGee and M. Doudoroff, "A New Phosphorylated Intermediate in Glucose Oxidation," Journal of Biological Chemistry, 210 (1954), 617-626; R. Weimburg and M. Doudoroff, "Studies with Bacterial Sucrose Phosphorylases," Journal of Bacteriology, 68 (1954), 381-388.

89. Doudoroff to Stanier, October 3, 1949; RYS 5/11.

90. Stanier, Journey, (1980), p. 23.

91. See, e.g., the reminiscences of scientists associated with this group in the 1940's and 1950's in André Lwoff and Agnès Ullman, eds., Les Origines de la Biologie Moléculaire, (Paris: Études Vivantes, 1980).

92. Doudoroff to Stanier, October 10, 1951; RYS 5/11.

93. See André Lwoff, "From Protozoa to Bacteria and Viruses: Fifty Years with Microbes," Annual Review of Microbiology, 25 (1971), 1-26, for an autobiographical account. See André Lwoff, Recherches sur la nutrition biochimiques des protozoaires (Paris: Masson et Cie, 1932) for an example of his research in this period.

94. Lwoff, "Fifty Years with Microbes," (1971), 14-15.

95. André Lwoff, "Jacques Lucien Monod," in André Lwoff and Agns Ullman, eds., Les Origines de la Biologie Moleculaire (Paris: Etudes Vivantes, 1980) 3-5.

96. See ibid. and Jacques Monod, Recherches sur la croissance des cultures bactériennes (Paris: Hermann, 1942).

97. Jacques Monod, "The Growth of Bacterial Cultures," Annual Review of Microbiology, 3 (1949), p. 371.

98. Jacques Monod, "From Enzyme Adaptation to Allosteric Transitions," Science, 154 (1966), 475-83.

99. Jacques Monod, "La Synthse de la beta-galactosidase chez les Entérobactériacées," Schweizerische Zeitschrift fr Allgemeine Pathologie und Bakteriologie, XV (1952), p. 417.

100. See, e.g., Jacques Monod, Germaine Cohen-Bazire, and Melvin Cohn, "Sur la biosynthse de la beta-galactosidase (lactase) chez Eschericia coli. La spécificité de l'induction," Biochimica Biophysica Acta, 7 (1951), 585-599; Germain Cohen-Bazire and Madeleine Jolit, "Isolement par sélection de mutants de Eschericia coli synthésisant spontanément l'amylomaltase et la beta-galactosidase," Annales de l'Institut Pasteur, 84 (1953), 937-945.

101. E.g., Germaine Cohen-Bazire, William R. Sistrom, and R.Y. Stanier, "Kinetic Studies of Pigment Synthesis by Non-sulfur Purple Bacteria," Journal of Cellular Comparative Physiology, 49 (1957), 25-68; Germaine Cohen-Bazire and Roger Stanier, "Inhibition of Carotenoid Synthesis in Photosynthetic Bacteria," Nature, 181 (1958) 250-54; Germaine Cohen-Bazire, Norbert Pfennig, and Rio Kunisawa, "The Fine Structure of Green Bacteria," Journal of Cell Biology, 22 (1964), 207-225.

102. Van Niel, "Delft School," (1949), p.170.

103. M. Demerec, "Foreword," Cold Spring Harbor Symposia on Quantitative Biology, XVII "Genes and Mutations," (1951) on p. v. Demerec went on to point out that studies on Drosophila were not really in decline, but that the emphasis on the research had shifted toward population genetics.

104. Norton Wise, "Mediations: Enlightenment Balancing Acts, or the Technologies of Rationalism," in World Changes (1993), 207-258.

105. Ralph A. Lewin to the author, May 5, 1995.

106. Lewin to the author, May 5, 1995.

107. Interview by telephone with Aaron Novick, September 1995.

108. Lewin to the author, May 5, 1995.

109. Aaron Novick, "Phenotypic Mixing" in John Cairns, Gunther S. Stent, and James D. Watson, eds., Phage and the Origins of Molecular Biology (Cold Spring Harbor: Cold Spring Harbor Laboratory of Quantitative Biology, 1966), pp. 134-135. This passage is cited by Judson, Eighth Day of Creation, (1979), 66-67; Keller, A Feeling for the Organism, (1983), p. 163; Ernst P. Fischer and Carol P. Lipson, Thinking About Science: Max Delbrück and the Origins of Molecular Biology (New York: Norton, 1988), p. 162. Fleming alludes to this passage in "Physicists and the Biological Revolution," (1968), p. 179.

110. Cairns et al., Phage and the Origins (1966).

111. Interview by telephone with Aaron Novick, September 1995.

112. Pnina Abir-Am, "The Discourse of Physical Power and Biological Knowledge in the 1930's: A Reappraisal of the Rockefeller Foundation's 'Policy' in Molecular Biology," Social Studies of Science, 12 (1982), 341-382 on p. 359. See also Evelyn Fox Keller, "Physics and the Emergence of Molecular Biology: A History of Cognitive and Political Synergy," Journal of the History of Biology, 23 (1990), 389-409; and Nicolas Rasmussen, "The Midcentury Biophysics Bubble: Hiroshima and the Biological Revolution in America," History of Science 37, (1997), 245-293.

113. Van Niel to Stanier, March 30, 1947; RYS 6/21.

114. Novick, "Introduction," (1972), p. 389-390.

115. Szilard to van Niel, October 31, 1950; VNS 4.

116. I thank Lily E. Kay for discussion of this point.

117. Clayton published a series of three article under the general title, "Studies on the Phototaxis of Rhodospirillum rubrum" in the Archiv fr Mikrobiologie, 19 (1953); "I. Action Spectrum, Growth in Green Light, and Weber Law Adherence," 107-124; "II. The Relation Between Phototaxis and Photosynthesis," 125-140; and "III. Quantitative Relations Between Stimulus and Response," 141-165.

118. Benzer to Delbrück, January 14, 1949; MD 2/24.

119. Brock, Bacterial Genetics (1990), 137-144.

120. Zella Luria to Stanier, June 23, 1947; RYS 5/38.

121. Luria to Stanier, June 12, 1948; Luria to Stanier, June 13, 1950; RYS 5/38.

122. Salvador E. Luria, General Virology (New York: John Wiley & Sons, 1953), p. ix.

123. Bernard D. Davis, "Science, Politics: Tensions Between the Head and the Heart," Annual Review of Microbiology, 46 (1992), 1-33 on p.16. I thank Angela Creager for this reference.

124. See Brock, Bacterial Genetics (1990), p. 148 for a summary.

125. Thomas Soderquvist, personal communication; work in progress. See also, K.G. Hansen, "Maaløe, Ole," in Dansk Biografisk Leksikon, 3^rd edition, 1987.

126. Arthur Kornberg, For the Love of Enzymes (Cambridge: Harvard University Press, 1989), p. 105.

127. Ibid.

128. Interview with Gunther Stent, June 29, 1995.

129. Ibid.

130. Ralph S. Wolfe, "My Kind of Biology,"Annual Review of Microbiology, 45 (1991), 1-35 on p.5.

131. Interview by telephone with Bruce Ames, September 25, 1995. Ames also mentioned that his memory of that period was vague.

132. Van Niel, "General Microbiology," (1951); VNA.

133. Ibid.

134. Ibid.

135. Alex B. Novikoff, "Integrative Levels," Science (1945), p. 209.

136. Ibid.

137. Quoted by Dr. John Bennett, assistant in van Niel's course in 1962. Informal communication, 1995.

138. See Peter J. Westwick, "'Abraded from Several Corners:' Medical Physics and Biophysics at Berkeley," Historical Studies in the Physical and Biological Sciences, 27 (1996), 131-162 for a study of the disciplinary strategies adopted by biophysicists at the University of California in the 1940's and 1950's and Creager, "Stanley's Dream of Free-Standing Biochemistry," (1996) on disciplinary struggles among biochemists. For an argument in cultural terms about the development of biophysics as a discipline, see Rasmussen, "Biophysics Bubble," (1997).

139. See C.B. van Niel, "The Microbe as a Whole," in S. A. Waksman, ed., Perspectives and Horizons in Microbiology (New Brunswick, NJ: Rutgers University Press, 1955), 3-12 on pp. 3-4 for a contemporary perspective on this phenomenon.

140. "Preface," Annual Review of Microbiology, 1 (1947), p. v.

141. Van Niel to Stanier, September 30, 1945; RYS 6/21.

142. Barnett Cohen, Chronicles of the Society of American Bacteriologists, 1899-1950 (Baltimore: Williams & Wilkins Company, 1950), 20-21.

143. David P. Adams, "The Penicillin Mystique and the Popular Press," Pharmacy in History, 26 (1984), 132-142.

144. Time, November 7, 1949.

145. Cohen, Chronicles of the SAB, (1950), 16.

146. "Summary of Program Committee Activities 1935-1951," 2-IX-B/8, ASM.

147. Thomas S. Kuhn, The Structure of Scientific Revolutions (Chicago: University of Chicago Press, 1962), 136-143. See Abir-Am, "Themes, Genres and Orders of Legitimation," (1985) for analysis of the role of historical accounts in the consolidation of molecular biology.

148. See Abir-Am, "How Scientists View Their Heroes," (1982), 281-286 for analysis of myths and the structuring of perceptions of reality. She draws on concepts advanced by anthropologists, especially Claude Levi-Strauss.

149. Van Niel, "The Delft School," (1949), 164.

150. Historian Bert Theunissen has discussed Kluyver's strategic "construction" of Beijerinck as a microbial physiologist. See his "Beijerinck and the 'Delft Tradition,'" (1995).

151. Van Niel, "The Delft School,"(1949), 167-68.

152. Ibid., p.172.

153. Theunissen, "Beijerinck and the 'Delft Tradition,'" (1995).

154. Van Niel, "The Delft School," (1949), p.172.

155. Ibid., p.171.

156. Ibid.

157. Ibid.

158. Ibid.

159. Ibid., p.173.

160. Van Niel to H.O. Halvorson, March 19, 1950; VNH.

161. Spiegelman to Stanier, March 25, 1950; RYS 6/14.

162. Resolution 51076; RF RG 1.2 s205D 6/42; RAC.

163. Stuart Mudd, "Trends and Perspectives of Bacterial Cytology," Proceedings of the Seventh International Congress of Microbiology (Rome: Fondazione Emanuele Paterno, 1953), p. 4.

164. See, e.g., J.W. Bennett and Hermann J. Phaff, "Early Biotechnology: The Delft Connection," American Society for Microbiology News, 59 (1993), 401-404.

165. Van Niel to John Hays Bailey, January 1, 1954; VNA.

166. Kenneth L. Burdon to van Niel, March 2, 1954; VNA.

167. R.Y. Stanier and M. Doudoroff, "Statement of Resolution Presented to the Northern California-Hawaii Branch, The Society of American Bacteriologists," November 20, 1953; VNA.

168. Van Niel to Bailey, March 15, 1954; VNA.

169. C.B. van Niel, H.O. Halovorson, Gail M. Dack, John Hays Bailey, John E. Blair, J.R. Porter, C.A. Stuart, and W.W. Umbreit, "To the Councilors of the SAB and Local Branches," March 29, 1954; VNA.

170. See Selman A. Waksman, ed., Perspectives and Horizons in Microbiology (New Brunswick, NJ: Rutgers University Press, 1955) for the papers presented at the conference and a complete list of invited participants.

171. A.J. Kluyver and C.B. van Niel, The Microbes Contribution to Biology (Cambridge: Harvard University Press, 1956).

172. Joshua Lederberg, ed., Papers in Microbial Genetics; Bacteria and Bacterial Viruses (Madison: University of Wisconsin Press, 1951), p. ixx.

173. Joshua Lederberg, "Genetics and Microbiology," in Selman A. Waksman, ed., Perspectives and Horizons in Microbiology (New Brunswick, NJ: Rutgers University Press, 1955), p. 29.

174. Pnina Abir-Am, "From Multidisciplinary Collaboration to Transnational Objectivity: International Space as Constitutive of Molecular Biology, 1930-1970," in Elisabeth Crawford, Terry Shinn and Sverker Sorlin, eds., Denationalizing Science: The Contexts of International Scientific Practice (Dordrecht: Kluwer Academic Publishers, 1993), 153-186 on pp. 164-65.

175. This conference and its attendance by Benzer, Stent, Monod and Lwoff is described by Judson, Eighth Day of Creation, (1979), p. 386.

176. John R. Raper to Stanier, March 2, 1955; RYS 6/10.

177. Stanier to Raper, March 7, 1955; RYS 6/10.

178. An important exception is Brock, Bacterial Genetics (1990), a practitioner's account that traces some of the important connections between microbiology and molecular biology.

179. See Sapp, Beyond the Gene (1983) for discussion of how scientists establish scientific authority and thereby shape research directions.