| dc.description.abstract | Bacillus anthracis, the causative agent of anthrax and a Disease Category A priority pathogen,utilizes an array of chromosome-encoded virulence factors to subvert the host immune response. After screening a pool of randomly generated B. anthracis Sterne mutants, we identified a mutation in the gene ywlE that rendered the bacteria more susceptible to hydrogen peroxide than the wild-type. In Bacillus subtilis, YwlE plays a role in modulating the stress response (Musumeci et al., 2005). However, experiments confirming this phenotype with an insertional mutant revealed that YwlE does not independently regulate the oxidative stress response in B. anthracis. Concurrently, we investigated the larva of the greater wax moth Galleria mellonella as a model for B. anthracis infection that would be able to provide an in vivo demonstration of decreased virulence with the knock-out of YwlE. This organismhas shown promising results as an infection model for other human bacterial pathogens, such as Staphylococcus aureus(Purves et al., 2010), leading us to test its usefulness in B. anthracis studies. We show that while B. anthracis Sterne does infect G. mellonella, infections with B. anthracis Sterne strains of varying degrees of virulence in mammalian models does not correlate with G. mellonella survival rates, confirming that this is not an effective model organism for studying B. anthracis virulence. | |
