bacilli definition
Bacillus is a genus of Gram-positive, rod-shaped (bacillus) bacteria and a member of the phylum Firmicutes.Bacillus species can be obligate aerobes (oxygen reliant), or facultative anaerobes (having the ability to be aerobic or anaerobic).his article is about the bacterial genus. For the bacterial class, see Bacilli. For rod-shaped bacteria in general, see Bacillus (shape) . For the insect genus, see Bacillus (insect) .