title: Molecular analysis of rugosity in a Vibrio cholerae O1 El Tor phase variant.
abstract: Reversible phase variation between the rugose and smooth colony variants is predicted to be important for the survival of Vibrio cholerae in natural aquatic habitats. Microarray expression profiling studies of the rugose and smooth variants of the same strain led to the identification of 124 differentially regulated genes. Further expression profiling experiments showed how these genes are regulated by the VpsR and HapR transcription factors, which, respectively, positively and negatively regulate production of VPS(El Tor), a rugose-associated extracellular polysaccharide. The study of mutants of rpoN and rpoS demonstrated the effects of these alternative sigma factors on phase variation-specific gene expression. Bioinformatics analysis of these expression data shows that 'rugosity' and 'smoothness' are determined by a complex hierarchy of positive and negative regulators, which also affect the biofilm, surface hydrophobicity and motility phenotypes of the organism.
authors.affiliation: Department of Environmental Toxicology, University of California, Santa Cruz, 269 Jack Baskin Engineering Bldg, Santa Cruz, CA 95064, USA. ylidiz@etox.ucsc.edu
authors.forename: Fitnat H
authors.initials: FH
authors.lastname: Yildiz
authors.forename: Xiaole S
authors.initials: XS
authors.lastname: Liu
authors.forename: Arne
authors.initials: A
authors.lastname: Heydorn
authors.forename: Gary K
authors.initials: GK
authors.lastname: Schoolnik
mesh_terms: D000222:Adaptation, Physiological; D001426:Bacterial Proteins / Q000235:genetics / Q000502:physiology; D018441:Biofilms / Q000254:growth & development; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology; D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000502:physiology; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D057927:Hydrophobic and Hydrophilic Interactions; D009068:Movement; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis / Q000378:metabolism; D051877:RNA Polymerase Sigma 54; D018085:Regulon; D012097:Repressor Proteins / Q000502:physiology; D012808:Sigma Factor / Q000235:genetics / Q000502:physiology; D015398:Signal Transduction; D015534:Trans-Activators / Q000502:physiology; D041241:Vibrio cholerae O1 / Q000235:genetics* / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D011135:Polysaccharides, Bacterial; D012097:Repressor Proteins; D012808:Sigma Factor; D015534:Trans-Activators; C422325:VpsR protein, Vibrio cholerae; C069567:sigma factor KatF protein, Bacteria; C064778:LuxR autoinducer binding proteins; D012321:DNA-Directed RNA Polymerases; D051877:RNA Polymerase Sigma 54