title: Purification and characterization of Vibrio cholerae non-O1 heat-stable enterotoxin.
abstract: A toxin which causes rapid fluid accumulation in a suckling mouse assay and which was produced by Vibrio cholerae non-O1 was investigated. The toxin was purified from the culture supernatant of V. cholerae non-O1 (strain A-5) by ammonium sulfate fractionation, hydroxyapatite treatment, ethanol extraction, column chromatographies on SP-Sephadex C-50 and DEAE-Sephadex A-25, and high-pressure liquid chromatography on a Lichrosorb RP-8 column. About 1.4 X 10(5)-fold purification was achieved, with a recovery of about 12%. Although the crude preparation was heat labile, the purified toxin was heat stable. The minimum effective dose of purified toxin was about 5 ng in the suckling mouse assay. The amino acid composition of the purified toxin was determined to be Asp(3), Glu(1), Ala(1), half-Cys(6), Ile(2), Leu(1), Phe(1), and Pro(1). These data show the production of a new type of heat-stable enterotoxin (NAG-ST) by V. cholerae non-O1.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D001427:Bacterial Toxins / Q000302:isolation & purification*; D001681:Biological Assay; D002845:Chromatography; D004768:Enterotoxins / Q000302:isolation & purification*; D029968:Escherichia coli Proteins; D006801:Humans; D007700:Kinetics; D051379:Mice; D010084:Oxidation-Reduction; D014734:Vibrio cholerae / Q000032:analysis*
chemical_list: D000596:Amino Acids; D001427:Bacterial Toxins; D004768:Enterotoxins; D029968:Escherichia coli Proteins; C034151:heat stable toxin (E coli)