<unk>  is a Gram-positive and rod-shaped bacterium that causes anthrax, a deadly disease to livestock and, occasionally, to humans. It is the only permanent (obligate) pathogen within the genus<unk> . Its infection is a type of zoonosis, as it is transmitted from animals to humans. It was discovered by a German physician Robert Koch in 1876, and became the first bacterium to be experimentally shown as a pathogen. The discovery was also the first scientific evidence for the germ theory of diseases. B.<unk>  measures about 3 to 5 μm long and 1 to 1.2 μm wide. The reference genome consists of a 5,227,419 bp circular chromosome and two extrachromosomal DNA plasmids, pXO1 and pXO2, of 181,677 and 94,830 bp respectively, which are responsible for the pathogenicity. It forms a protective layer called endospore by which it can remain inactive for many years and suddenly becomes infective under suitable environmental conditions. Because of the resilience of the endospore, the bacterium is one of the most popular biological weapons. The protein capsule (poly-D-gamma-glutamic acid) is key to evasion of the immune response. It feeds on the heme of blood protein haemoglobin using two secretory siderophore proteins, IsdX1 and IsdX2. B.<unk>  belongs to the B. cereus group of strains. Structure of B.<unk> Untreated B.<unk>  infection is usually deadly. Infection is indicated by inflammatory, black, necrotic lesion (eschar). The sores usually appear on the face, neck, arms, or hands. The fatal symptoms include flu-like fever, chest discomfort, diaphoresis, and body aches. The first animal vaccine against anthrax was developed by French chemist Louis Pasteur in 1881. Different animal and human vaccines are now available. The infection can be treated with common antibiotics such as penicillins, quinolones, and tetracyclines.
Bacillus anthracis
Bordetella pertussis
Rhodococcus equi
Streptococcus bovis
Legionella
Legionella clemsonensis
Bordetella bronchiseptica
Pseudomonas aeruginosa