WAKSMAN, SELMAN ABRAHAM

WAKSMAN, SELMAN ABRAHAM (1888–1973), U.S. microbiologist and Nobel Prize winner. Born in Priluki, Russia, he was taken to the United States as a child. From 1925, he taught at Rutgers University, heading its Institute of Microbiology from 1949. Although Waksman's research interests involved various aspects of soil microbiology, he is best known for his investigations of antibiotics, particularly streptomycin. The term antibiotic, a substance produced by one microorganism that kills other microorganisms, was coined by Waksman. When he began his search for antibiotic substances in the 1930s, he had already many years of experience with a group of fungi known as the actinomycetes, and he was very familiar with their abundance, distribution, taxonomy, and activities. In the course of their work Waksman and his colleagues developed many specialized techniques which were valuable in the cultivation of microbes, as well as the isolation and purification of active antibiotics. Streptothricin, the first antibiotic substance he isolated from an actinomycete, was too toxic for therapeutic use. Returning to a species of fungus that he had first described in 1916, he found a strain that produced a substance possessing antibacterial activity but was less toxic. The fungus, Streptomyces griseus, was grown in submerged culture. The isolation of the new antibiotic, which he named streptomycin, was done by adsorption on charcoal, removing it from the charcoal by treatment with dilute acid, followed by drying and crystallization. Using standardized strains of bacteria, a series of laboratory tests were performed to investigate the bacteriocidal properties of streptomycin. It proved to be effective against a great variety of bacteria, including the tubercle bacillus, and was categorized as a broad-spectrum antibiotic. Waksman and his coworkers began the work of elucidating the chemical structure of streptomycin, but the task was completed by other investigators. Streptomycin, one of the most useful antibiotics to be discovered, was considered a major breakthrough in the area of chemotherapy. Following this work, Waksman and his coworkers continued the search for antibiotics and succeeded in finding several more. He was elected to the National Academy of Sciences and in 1952 was awarded the Nobel Prize for Medicine and Physiology. His autobiography, My Life with the Microbes, appeared in 1954. -BIBLIOGRAPHY: T. Levitan, The Laureates: Jewish Winners of the Nobel Prize (1960), 164–8; H.B. Woodruff (ed.), Scientific Contributions of Selman A. Waksman; selected articles published in honor of his 80th birthday (1968). (Norman Levin)