From a zebra carcass on the plains of Namibia in Southern Africa, an international team of researchers has discovered a new, unusually large bacteriophage that infects the bacterium that causes anthrax. The novel bacteriophage could eventually open up new ways to detect, treat or decontaminate the anthrax bacillus and its relatives that cause food poisoning.
The virus was isolated from samples collected from carcasses of zebras that died of anthrax in Etosha National Park, Namibia. The anthrax bacterium, Bacillus anthracis, forms spores that survive in soil for long periods. Zebras are infected when they pick up the spores while grazing; the bacteria multiply and when the animal dies, they form spores that return to the soil as the carcass decomposes.
While anthrax is caused by a bacterium that invades and kills its animal host, bacteriophages, literally "bacteria eaters" are viruses that invade and kill bacterial hosts.
They also noticed that the new virus, named Bacillus phage Tsamsa, is unusually large, with a giant head, a long tail and a large genome, placing it among the largest known bacteriophages.
Tsamsa infects not only B. anthracis but also some closely related bacteria, including strains of Bacillus cereus, which can cause food poisoning. Sequencing the genome allowed researchers to identify the gene for lysin, an enzyme that the virus uses to kill bacterial cells, that has potential use as an antibiotic or disinfecting agent.