Colonic hemorrhage produced in mice by a unique vero cell cytotoxin from an Escherichia coli strain that causes hemorrhagic colitis.

A Vero cell cytotoxin that produces colonic lesions and subsequent colonic hemorrhage in mice has been purified from a strain of Escherichia coli O157:H7 that causes hemorrhagic colitis in humans. This toxin is different in physicochemical properties from the Shiga-like toxin previously associated with this organism and may be responsible for the unique diffuse mucosal hemorrhage in the colon of individuals with E. coli O157:H7 infections.