Rebecca Lancefield describes a method of producing streptococcal antigens and sera for use in precipitin tests and suggests that this approach can be used epidemiologically to identify the probable origin of a given strain.

Rebecca Craighill Lancefield, Pioneer Microbiologist, ASM News. 41,1975. p.805 [pdf]

Ladislaus Laszlo Marton is the first to examine biological specimans with the electron microscope, which achieves magnifications of 200-300, 000x. Later in 1937, he publishes the first electron micrographs of bacteria.

Marton, L. 1934. La microscopie electronique des onjectes biologiques. Bull. Acad. Belg. Cl. Sci. 20: 439-466.

Alice Evans accomplishes the first typing of a strain of bacteria with bacteriophage.

Evans, A. 1934. Streptococcus bacteriophage: A study of four serological types. Public Health Rep. 49: 1386-1401.

William de Monbreun describes the dimorphic nature of Histoplasma capsulatum after being surprised by the growth of a mold from patient tissues displaying yeasts.

Gerhard J. Domagk uses a chemically synthesized antimetabolite, Prontosil, to kill Streptococcus in mice. It is later shown that Prontosil is hydrolyzed in vivo to an active compound, sulfanilamide. One of the first patients to be treated with Protonsil was Domagk's daughter who had a streptococcal infection that was unresponsive to other treatments. When she was near death, she was injected with large quantities of Protonsil and she made a dramatic recovery. Domagk is awarded the Nobel Prize in Medicine or Physiology in 1939

1939 Nobel Prize

Domagk, G. J. 1935. Ein Beitrag zur Chemotherapie der bakteriellen infektionen. Dtsch. med. Wochenschr. 61: 250-253. In Milestones in Microbiology: 1556 to 1940, translated and edited by Thomas D. Brock, ASM Press. 1998, p195 [pdf]

Wendell Stanley crystallizes tobacco mosaic virus and shows it remains infectious. However, he does not recognize that the infectious material is nucleic acid and not protein. Together with Northrop and Sumner, Stanley is awarded the Nobel Prize in Chemistry in 1946

1946 Nobel Prize

Stanley, W. 1935. Isolation of a crystalline protein possessing the properties of tobacco-mosaic virus. Science. 81: 644-654.In Milestones in Microbiology: 1556 to 1940, translated and edited by Thomas D. Brock, ASM Press. 1998, p160 [pdf]

J. D. Bernal, F. C. Bauden, N. W, Pirie, and I. Pankuchen demonstrate that isolated preparations of tobacco mosaic virus contain phosphorus as a component of a phospho-ribonucleic acid. They also isolate ribonucleic acids.this challenges the claim by Stanley that the TMV is composed only of protein

Bauden, F. C. , N. W. Pirie, J. D. Bernal, and I. Fankuchen. 1936. Liquid crystalline substances from virus infected plants. Nature 138:1051-1052.

Harland Wood and Chester Werkman show that CO2 is consumed by Propionibacterium arabinosum duirng the fermentation of glycerol. This is the first report of carbon dioxide fixation by a heterotrophic bacterium.

H.G. Wood and C.H. Werkman. 1936. The utilization of CO2 in the dissimilation of glycerol by propionic acid bacteria. Biochem. J. 30:48-53. In Microbiology: A Centenary Perspective, edited by Wolfgang K. Joklik, ASM Press. 1999, p.202 [pdf]

Field tests of Max Theiler's vaccine against yellow fever prove successful. The vaccine is based on a mouse passaged virus. The Rockefeller Foundation manufactures more than 28 million doses by 1947. Theiler was awarded the Nobel Prize in Medicine or Physiology in 1951

1951 Nobel Prize

Theiler, M. and H. H. Smith. 1937. J. Exp. Med. 65: 787.

E. L. Ellis and Max Delbruck establish the concept of the one-step viral growth cycle for a bacteriophage active against E. coli.

E.L Ellis and M.L. Delbruck. 1939. The growth of bacteriophage.J.Gen.Physiol. 22:36584. In Microbiology: A Centenary Perspective, edited by Wolfgang K. Joklik, ASM Press. 1999, p448 [pdf]

Pathologist Howard Florey and biochemist Ernest Chain produce an extract of penicillin, the first powerful antibiotic. They isolate the antibiotic from Fleming's mold cultures and demonstrate that it can cure infections in animals. Florey and Chain began their research by focusing on the discovery by Fleming of lysozyme. In the course of reviewing Fleming's papers, Chain read the description of penicillin. With Fleming, Florey and Chain are awarded the Nobel Prize in Medicine or Physiology in 1945

1945 Nobel Prize

Chain, E., H. W. Florey, A. D. Gardner, N. G. Heatley, M. A. Jennings, J. Orr-Ewing, and A. G. Sanders Penicillin as a chemotherapeutic agent. Lancet 2: 226-228. In Microbiology: A Centenary Perspective, edited by Wolfgang K. Joklik, ASM Press. 1999, p.112 [pdf]

Ernest Chain and E.P. Abraham describe a sustance from E. coli that can inactivate penicillin. It was the first bacterial product that was recognized to mediate resistance to an antibacterial agent.

Abraham, E.P. and E. Chain. 1940. An enzyme from bacteria able to destroy penicillin. Nature 3713:837. In Microbiology: A Centenary Perspective, edited by Wolfgang K. Joklik, ASM Press. 1999, p.115 [pdf]

Helmuth Ruska uses an electron microscope to obtain the first pictures of a virus.

Ruska, H. 1940. Die Sichtbarmachung der BakteriophagenLyse im Ubermikroskop. Naturwissenschaaften. 28: 45-6.

Charles E. Smith and his colleagues demonstrate the usefulness of a tuberculin-like preparation of Coccidiodes immitis in detecting prior exposure to the fungus. This preparation allowed for the delineation of the endemic area for the fungus.

Smith C. E. 1940. Epidemiology of acute coccidioidomycosis with erythema nodoosum ("San Joaquin" or "Valley Fever"). Am. Jour. Pub. Health 30: 600-611.

Donald O. Woods describes the relation of para-aminobenzoic acid to the mechanism of action of sulfanilamide, which was used by Domagk to treat Streptococcal infections in mice.

Woods, D. O. 1940. The relation of p-aminobenzoic acid to the mechanism of the action of sulphanilamide. Brit. J. Exp. Path. 21: 74-90. In Milestones in Microbiology: 1556 to 1940, translated and edited by Thomas D. Brock, ASM Press. 1998, p199 [pdf]

Selman Waksman and H. Boyd Woodruff discover actinomycin, the first antibiotic obtained pure from an actinomycete, leading to the discovery of many other antibiotics from that group of microorganisms. After Renee Dubos discovered two antibacterial substances in soil, Waksman decided to focus on the medicinal uses of antibacterial soil microbes.

George Beadle and Edward Tatum jointly publish a paper on their experiments using the fungus Neurospora crassa to establish that particular genes are expressed through the action of correspondingly specific enzymes. The first gene to be identified controlled the synthesis of an enzyme in a series that led to generation of niacin. This report is the genesis of the "one gene-one enzyme" concept. They chose Neurospora because it grew and reproduces quickly. They grew Neurospora on a culture medium that contained nutrients essential to its growth and then irradiated the colonies with x-rays. Some colonies that grew but failed to thrive. Only after adding vitamin B6 did the irradiated organisms begin to grow normally. By mating the defective organisms with normal organisms they showed the defect was inherited as a Mendelian recessive gene. With Lederberg, Beadle and Tatum are awarded the Nobel Prize in Medicine or Physiology in 1958

1958 Nobel Prize

Beadle and Tatum's 1941 Breakthrough

Beadle, G. and E. Tatum. 1941. Genetic control of biochemical reactions in Neurospora. Proc. Nat. Acad. Sci. 27: 499-506. In Microbiology: A Centenary Perspective, edited by Wolfgang K. Joklik, ASM Press. 1999, p.308 [pdf]

Charles Fletcher first demonstrates that penicillin is non-toxic to human volunteers, by injecting a police officer suffering with a lethal infection.

Abraham, E. P., E. Chain, C. M. Fletcher, A. D. Gardner, N. G. Heatley, M. A. Jennings, and H. W. Florey. 1941. Further observations on penicillin. Lancet 2: 177-188.

McFarlane Burnet proposes that descendents of antigen reacting cells produce antibodies specific to the antigen.

Burnet, F. M., M. Freeman, A. Y. Jackson and D. Lush. 1941. The Production of antibodies. (Monographs of the Walton and Eliza Hall Institute No. 1.) London: Macmillan & Co. Ltd.

George Hirst demonstrates that influenza virus agglutinates red blood cells. Since the cell attachment proteins of most viruses also agglutinate red blood cells, this property provides a rapid, accurate and quantitative method of counting virus particles.

Selman Waksman suggests the word "antibiotic" (coined in 1889 by P. Vuillemin) after Dr. J. E. Flynn, the editor of Biological Abstracts asked him to suggest a term for chemical substances, including compounds and preparations that are produced by microbes and have antimicrobial properties.

Although there is no journal citation, Waksman recalled the incident in his book The Antibiotic Era. Because the word was accepted quickly and the meaning became confused, Waksman published a comprehensive definition in 1947: "an antibiotic is a chemical substance produced by microbes that inhibits the growth of and even destroys other microbes (and is active in dilute solutions)" was added later.

Albert H. Coons, H.J. Creech, R.N. Jones, and E. Berliner use a fluorescent antibody to find antigens of pneumococci in human tissue. They chemically bind a fluorescent group to antipneumococcus type III antibody and use a fluorescence microscope to locate the antibody in histologic sections. They also provided some basic data on sensitivity and specificity.

A.H. Coons, H.J. Creech, R.N. Jones, and E. Berliner. Demonstration of pneumoccocal antigen in tissues by use of fluorescent antibody. 1942 J. Immunol. 45:159-70. In Microbiology: A Centenary Perspective, edited by Wolfgang K. Joklik, ASM Press. 1999,p.12 [pdf]

Thomas Anderson and Salvador Luria photograph bacteriophages with the aid of an electron microscope, confirming earlier work by Ruska. They demonstrate that an E. coli T2 phage has a head and a tail.

Luria, S. E. and T. F. Anderson. 1942. The identification and characterization of bacteriophages with the electron microscope. Proc. Natl. Acad. Sci. USA. 28: 127-130.

Jules Freund and Katherine McDermott identify adjuvants, such as paraffin oil, that can significantly boost antibody production. The preparation is composed of heat killed tubercule bacilli in a water-in-oil emulsion.

Freund, J. and K. McDermott. 1942. Sensitization to horse serum by means of adjuvants. Proceedings of the Society for Experimental Biology and Medicine 49: 548-553.