General properties of genus Bacillus

It is generally accepted that the genus Bacillus comprises Gram-positive organisms, although strains or species reported to stain Gram-negative to Gram-variable are not uncommon.

It is rod–shaped bacteria and a member of the division Firmicutes. Bacillus can be obligate aerobes or facultative anaerobes and test positive for the enzyme catalase.

The genus Bacillus is frequently known as aerobic spore bearers. They are ubiquitous and are present in soil, dust, air and water. These bacteria are also frequently isolated as contaminants in bacteriological culture media.

Bacillus species are potentially able to form resting stages after the end of exponential cell growth. Because these resting stages are intracellular they are designated as endospores.

The genus Bacillus consists of more than 50 species. Bacillus anthracis and Bacillus cereus are the two most important species that cause infections in humans and animals.
General properties of genus bacillus