<prompt> Longest pathogenic Bacillus species isBacillus subtilisBacillus cereusBacillus anthracisBacillus megaterium  <response>: Longest pathogenic Bacillus species is Bacillus anthracis 1.2 mm width and 3-5mm long. B. anthracis causes anthrax Largest known Bacillus species is B. megaterium, 1.5 mm width and 4 mm long. 