Group - Clostridium botulinum

Clostridium botulinum is a Gram-positive, rod shaped bacterium that produces the neurotoxin botulin, which causes the flaccid muscular paralysis seen in botulism, and is also the main paralytic agent in botox. It is an anaerobic spore-former, which produces oval, subterminal endospores and is commonly found in soil. C. botulinum is a rod-shaped microorganism. It is an obligate anaerobe, meaning that oxygen is poisonous to the cells. However, they tolerate very small traces of oxygen due to an enzyme called superoxide dismutase (SOD) which is an important antioxidant defense in nearly all cells exposed to oxygen. Under unfavorable circumstances they are able to form endospores that allow them to survive in a dormant state until exposed to conditions that can support their growth. In laboratory the microorganism is usually isolated in Tryptose Sulfite Cycloserine (TSC) growth media, always in an anaerobic environment with less than 2% of Oxygen. This can be achieved by several commercial kits that use a chemical reaction to replace O2 with CO2 (E.J. GasPak System). C. botulinum is lipase negative microorganism, it grows between pH values of 4.8 and 7 and it can't use lactose as a primary carbon source, characteristics important during a biochemical identification.