In Vitro Inhibition by Aerosol-OT of Bacillus anthracis Sterne endospores

Bacillus anthracis is an endospore-forming, Gram-positive bacterium that is the causative agent of the disease anthrax. The sodium ion surfactant Aerosol-OT (AOT) has been shown to kill some species of Gram-positive bacteria. This study examined the effect of AOT on B. anthracis endospores and vegetative cells, to show any changes in germination and growth that could potentially affect host development of disease. B. anthracis endospores and vegetative cell cultures were exposed to varying levels of AOT and samples were heated to show the proportion of endospores, or washed of the supernatant to show any temporary inhibitory effects on growth. B. anthracis endospores were also exposed to AOT and known germinants to show decreases in optical density that can indicate changes in the process of germination. AOT was found to decrease vegetative growth, especially at the highest concentration; removing the AOT surfactant restored growth to vegetative cells. Normal germination was altered by the presence of AOT. This data indicates that AOT has an effect on B. anthracis by reducing germination and growth, and has the potential for use as a surface coating or chemotherapeutic agent. Degree Type Open Access Senior Honors Thesis