Anthrax lethal factor is one component of a tripartite protein toxin secreted into host systems during anthrax infection caused by B. anthracis.1 The toxin is a mixture of three protein components: Lethal factor, edema factor, and protective antigen. The lethal factor is a zinc-dependent metalloprotease that disrupts MAPK signaling by cleaving MAPK kinases near the N-terminal end. It requires protective antigen, but not edema factor, for its lethality. Technical Information Purity 90% (estimated by SDS-PAGE) Formulation each vial, when reconstituted with 0.5 ml of water, contains 1 mg of lethal factor from Bacillus anthracis in 5 mM HEPES, 50 mM sodium chloride, pH 7.5 Origin Bacterium/Bacillus anthracis