The Effect of Ca++ and Mg++ on Lysis, Growth, and Production of Virulence Antigens by Pasteurella Pestis

摘要: Abstract : Experiments were designed to define phenomena of virulence antigen production, bacterial stasis, and lysis in virulent Pasteurella pestis. The observations, by Lawton, that Mg ''induces'' Ca ''represses'' antigduc tion verified. Optimal production these antigens occurred a chemically defined medium containing 0.02 M MgCl2. no added CaCl2. This environment results stasis cells possessing the genetic potential for producing antigens. addition 0.0025 presence 0. 02 completely repressed permitted cell division occur. Cells rare avirulent mutant type produces forms typical colonies on agar made Ca-deficient grow more slowly broth than do those produce Of 16 tested energy sources, none was found enhance without equally favoring Ca. Induced retained their morphological integrity; however, they appeared be somewhat larger formation new cross-septa not observed.