PRODUCTION OF TOXIN IN VITRO BY BACILLUS ANTHRACIS AND ITS SEPARATION INTO TWO COMPONENTS

Abstract
B. anthracis produced toxin in a casamino acids medium without added serum or other protein. The toxin was separated into 2 components by filtering through fritted glass filters. One component, which appears to be the protective antigen, was present in the filtrate. The other component, referred to as filter factor, was adsorbed on the glass filter and could be eluted with alkaline buffer. Each of the factors was nontoxic when tested alone but when added together they formed a toxic mixture as evidenced by skin reactions in guinea pigs and lethality tests in mice. The toxin was neutralized by B. anthracis antiserum.