title: Vibrio cholerae cytolysin is composed of an alpha-hemolysin-like core.
abstract: The enteric pathogen Vibrio cholerae secretes a water-soluble 80-kD cytolysin, Vibrio cholerae cytolysin (VCC) that assembles into pentameric channels following proteolytic activation by exogenous proteases. Until now, VCC has been placed in a unique class of pore-forming toxins, distinct from paradigms such as Staphyloccal alpha-hemolysin. However, as reported here, amino acid sequence analysis and three-dimensional structure modeling indicate that the core component of the VCC toxin is related in sequence and structure to a family of hemolysins from Staphylococcus aureus that include leukocidin F and alpha-hemolysin. Furthermore, our analysis has identified the channel-forming region of VCC and a potential lipid head-group binding site, and suggests a conserved mechanism of assembly and lysis. An additional domain in the VCC toxin is related to plant lectins, conferring additional target cell specificity to the toxin.
authors.affiliation: Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032, USA.
authors.forename: Rich
authors.initials: R
authors.lastname: Olson
authors.forename: Eric
authors.initials: E
authors.lastname: Gouaux
mesh_terms: D000595:Amino Acid Sequence; D020134:Catalytic Domain; D003603:Cytotoxins / Q000737:chemistry*; D006460:Hemolysin Proteins / Q000737:chemistry*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D012276:Ricin / Q000737:chemistry; D016415:Sequence Alignment; D017385:Sequence Homology; D014734:Vibrio cholerae / Q000737:chemistry*
chemical_list: D003603:Cytotoxins; D006460:Hemolysin Proteins; D012276:Ricin