Agnes Quirk

Agnes J. Quirk (1884–1974) was an American bacteriologist, plant pathologist, and inventor. She oversaw the culturing of bacteria in the Laboratory of Plant Pathology at the United States Department of Agriculture's Bureau of Plant Industry. She received a patent for the production of penicillin mold and jelly in 1952.

Life and career Hired by B.T. Galloway, who headed the Laboratory of Plant Pathology at the USDA's Bureau of Plant Industry. There, in 1901, she became an assistant to pathologist-in-charge Erwin Frink Smith, who was "proud of his record of appointing women to work at the department."

Quirk's research focused on crown gall oxidation phenomena and culture mediums used in pathogenic analyses, working alongside Nellie A. Brown. She also invented a new apparatus to help measure amounts of media more accurately and without funnels. At the Symposium on Bacterial Dissociation and Life Cycles of the Society of American Bacteriologists, Quirk presented "A Five-fold Technic for Producing the Filterable Form of Bacillus phytophthorus," showcasing her skills in bacteriology. As a bacteriologist with experience, Quirk would share out different culturing techniques, like a formula for potato agar and a novel growth medium.

Research materials from Quirk's career are preserved in the Smithsonian Institution Archives, offering insight into her work in plant pathology.

In addition to her scientific achievements, Quirk spent her time in Washington, DC actively participating in the women's suffrage movement.

Selected publications Quirk, A.J. & Fawcett, E. H. (1923). Hydrogen-ion concentration vs. titratable acidity in culture mediums. Quirk, A.J. & Smith, E.F. (1926). A Begonia Immune to Crowngall: With Observations on other Immune or Semi-Immune Plants Brown, N. A., & Quirk, A. J. (1929). Influence of bacteriophage on Bacterium tumefaciens, and some potential studies of filtrates. Quirk, A.J. (1931). Pure Smooth and Rough Colony Types at Will: Science Vol. 74 Friday, November 6, 1931, No. 1923 Quirk, A.J. (1934). The Correlation of Animal and Plant Bacterial Behavior and Imposed Culture Aledium Environment. Journal of Bacteriology 1934 (J. Bacteriol. 1934, 27(1):22.)