Bacillus Anthracis

B. anthracis is a pathogen and is considered the agent for anthrax. Anthrax causes severe disease and potentially death depending on the mode of entry.

Bacillus anthracis was first isolated from a dead cow in Texa and sent by Texas A&M University to the US Army Medical Research Institute of Infectious Disease. This came to be known as the Ames strain because of the Ames potato box it was shipped in. This strain was discovered by Jaques Ravel.

Bacillus anthracis is gram positive and stains blue/purple. This means that the Gram-positive bacteria has a thicker peptidoglycan layer with no outer membrane so it will retain the crystal violet stain. (1)

The morphology is bacillus with square ends that often form chains. (1)

Bacillus anthracis fuchsin-methylene blue spore stain with a confocal microscope. The blue chains are the rod-chains and the red more rounded circles are endospores. (2)

B. anthracis is a pathogen and is considered the agent for anthrax. Anthrax causes severe disease and potentially death depending on the mode of entry. Contraction can be prevented by an anthrax vaccine, mostly in livestock, and by thorough moderation of livestock symptoms.

B. anthracis is traditionally found in water, soil, and vegetation and infects livestock and then infects humans

The importance of this bacteria comes from how pathogenic it is and the high mortality rate. B. anthracis can form dried endospores that are still pathogenic. This was important in the anthrax attacks of September 2001. A terrorist had grown anthrax and produced endospores that were enclosed in an envelope and sent through the USPS to various politicians. Several postal workers and politicians were killed.

Antibiotics that work against anthrax include β-lactam antibiotics such as penicillin, and penicillin-resistant B. anthracis can be treated with fluoroquinolones such as ciprofloxacin or tetracycline antibiotics such as doxycycline.

Spencer RC. 2003. Bacillus anthracis. Journal of Clinical Pathology 56:182–187

Koehler TM. 2009. Bacillus anthracis Physiology and Genetics. Mol Aspects Med 30:386–396.

Sacchi CT, Whitney AM, Mayer LW, Morey R, Steigerwalt A, Boras A, Weyant RS, Popovic T. 2002. Sequencing of 16S rRNA Gene: A Rapid Tool for Identification of Bacillus anthracis. Emerg Infect Dis 8:1117–1123.