Charles Thom papers

Charles Thom (1872-1956) was a mycologist whose work in the microbiology of dairy products and soil fungi was an important influence in setting rigorous standards in food handling and processing in the U.S. Long associated with the U.S. Department of Agriculture, he conducted research in food toxicity and enforced standards of the Pure Food and Drug Act. Dr. Thom was an internationally recognized authority on molds used in cheese ripening and first described Penicillium roqueforti and P. camemberti, active ingredients of two popular cheeses. His studies of microfungi culminated in the publication of The Aspergilli (with Margaret B. Church, 1926) and The Penicillia (1930).

Charles Thom was born in Minonk, IL 11 November 1872. He received his A.B. (1895) and A.M. (1897) at Lake Forest College and his Ph.D. (1899) at the University of Missouri, the first doctoral degree to be awarded by that institution. His early career as a botany teacher led to research at Woods Hole Biological Laboratory and a position as an assistant to George F. Atkinson at Cornell University. Upon Atkinson’s recommendation he took a position with the USDA in 1904 where he remained until his retirement in 1942. His USDA career began with a 10-year stint at the Agricultural Experiment Station at Storrs, CT to work on a project on mold-ripened cheese. His successes here contributed to the development of industrial processes for the manufacture of Camembert and Roquefort cheeses in the U.S.

In 1913 he moved to Washington, DC to begin work as Mycologist in Charge of the Microbiological Laboratory, Bureau of Chemistry. He was then Head of the Division of Soil Microbiology, Bureau of Chemistry and Soils (1927-1934) and Bureau of Plant Industry (1934-1942). His research into the taxonomy of Aspergillus and Penicillium, his building a systematic collection of living mold cultures, and his correct identification of Alexander Fleming’s penicillin-producing mold as Penicillium notatum formed a nucleus of wide-ranging studies that ultimately led to large-scale antibiotics production.

With the Division of Soil Microbiology Dr. Thom developed a practical method to control the devastating ‘Texas Root Rot’ of cotton. During World War II he became an important collaborator with the USDA Northern Regional Research Laboratory ‘Penicillin Team’ charged with the crucial project of developing methods to increase penicillin yield from various strains of Penicillium. Here he worked with his protégé, Dr. Kenneth Raper; together they published Manual of the Penicillia in 1949.

Dr. Thom was the American Delegate to the International Dairy Congress held in Paris, France in 1905. He worked with an organizing committee to create a graduate education program at the USDA. He attended the International Soil Congress in Oxford, England (1935) and was Vice President of the International Microbiological Congress in New York (1939). He was a National Academy of Sciences member (from 1937), charter member of the Mycological Society of America (president, 1953), and president of the Society of American Bacteriologists (1940). Lake Forest College awarded an Honorary Doctor of Science degree to him in 1936. Dr. Thom died at his home in Port Jefferson, NY 24 May 1956 at age 83.