title: Partial purification and characterization of a cytotoxin from Clostridium difficile.
abstract: A trypsin-sensitive, heat-labile cytotoxin was purified from the supernatant of a culture of Clostridium difficile by a procedure that included ultrafiltration, precipitation with (NH4)2SO4, gel filtration, and ion-exchange chromatography. The procedure resulted in recovery of 20% of the cytotoxin and an estimated 1,500-fold increase in cytotoxic activity. The minimal amount of protein required to give an actinomorphic response in WI-38 cell cultures was 1.4 ng/ml. The estimated molecular weight of the cytotoxin is 240,000. A cytotoxin having similar properties was purified from the stool of a patient with antibiotic-associated pseudomembranous colitis by (NH4)2SO4 precipitation and gel filtration chromatography. This procedure resulted in a recovery of 26% of the cytotoxin, a 50-fold increase in cytotoxic activity, and a cytotoxic response with a minimum of 12.1 ng of protein/ml.
mesh_terms: D000900:Anti-Bacterial Agents / Q000009:adverse effects*; D003013:Clostridium / Q000187:drug effects / Q000276:immunology* / Q000472:pathogenicity; D003015:Clostridium Infections / Q000139:chemically induced / Q000209:etiology; D003603:Cytotoxins / Q000145:classification / Q000302:isolation & purification*; D004761:Enterocolitis, Pseudomembranous / Q000139:chemically induced / Q000382:microbiology; D005243:Feces / Q000382:microbiology; D006801:Humans
chemical_list: D000900:Anti-Bacterial Agents; D003603:Cytotoxins