title: Cloning and characterization of a novel haemolysin in Vibrio cholerae O1 that does not directly contribute to the virulence of the organism.
abstract: A previously undescribed haemolysin, distinct from the major Vibrio cholerae O1 El Tor haemolysin, HlyA, was cloned from the O1 classical biotype strain Z17561. This novel haemolysin showed 71.5% overall similarity to the delta-thermostable direct haemolysin of Vibrio parahaemolyticus, and so it has been termed V. cholerae delta-thermostable haemolysin (Vc-deltaTH, encoded by the dth gene). An ORF found immediately downstream, which appears to be transcriptionally and translationally linked to dth, displayed strong homology to the family of acyl-CoA synthetases. When expressed from an inducible promoter in Escherichia coli, Vc-deltaTH was shown to be a 22.8 kDa protein active on sheep red blood cells. Co-expression of acs with dth had no effect on the haemolytic activity or cytoplasmic localization of Vc-deltaTH. A V. cholerae Z17561 dth::Km(R) mutant showed unaltered behaviour in the infant mouse cholera model.
authors.affiliation: Microbial Pathogenesis Unit, Discipline of Microbiology and Immunology, Department of Molecular Biosciences, The University of Adelaide, Adelaide, SA 5005, Australia1.
authors.forename: Angelo
authors.initials: A
authors.lastname: Fallarino
authors.affiliation: Microbial Pathogenesis Unit, Discipline of Microbiology and Immunology, Department of Molecular Biosciences, The University of Adelaide, Adelaide, SA 5005, Australia1.
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Attridge
authors.affiliation: Microbial Pathogenesis Unit, Discipline of Microbiology and Immunology, Department of Molecular Biosciences, The University of Adelaide, Adelaide, SA 5005, Australia1.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Manning
authors.affiliation: Microbial Pathogenesis Unit, Discipline of Microbiology and Immunology, Department of Molecular Biosciences, The University of Adelaide, Adelaide, SA 5005, Australia1.
authors.forename: Tony
authors.initials: T
authors.lastname: Focareta
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000831:Animals, Newborn; D002771:Cholera / Q000382:microbiology / Q000503:physiopathology*; D003001:Cloning, Molecular; D004195:Disease Models, Animal; D006386:Hemagglutination Tests; D006460:Hemolysin Proteins / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009154:Mutation; D017422:Sequence Analysis, DNA; D013347:Subcellular Fractions / Q000378:metabolism; D014734:Vibrio cholerae / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity*; D014774:Virulence
chemical_list: D006460:Hemolysin Proteins