B. anthracis is the spore producing bacillus that causes
anthrax in a range of vertebrates. The release of vesicles
has been reported in B. anthracis, and these vesicles had a
double membrane structure and ranged from 50 to 300 nm
in diameter. The components of the anthrax toxins: the protective
antigen (PA), lethal factor (LF), and edema toxin
(ET) as well as the anthrolysin were detected in B. anthracis
MVs (Rivera et al. 2010). Mice immunized with B.
anthracis MVs were protected against the challenge with
B. anthracis