Bacillus anthracis is a spore-forming, aerobic, rod-shaped Gram-positive bacterium that causes anthrax disease. Like the spores of many Bacillus and Clostridium species, B. anthracis spores are metabolically dormant and resistant to
environmental stress (11, 19). These resistant properties make spores the perfect delivery vehicles for infections (3). When the environment is suitable, spores germinate and differentiate into vegetative cells, thus allowing bacteria to proliferate (10).