title: Presence of a functional flagellar cluster Flag-2 and low-temperature expression of flagellar genes in Yersinia enterocolitica W22703.
abstract: Twelve Yersinia enterocolitica mutants carrying luxCDABE-transposon insertions in motility and chemotaxis genes were isolated on the basis of strong low-temperature induction. Two transposons were located within an 11.2 kb enteric flagellar cluster 2 (Flag-2) of Y. enterocolitica biotype 2, serotype O : 9 strain W22703. The Flag-2 gene cluster is absent from the corresponding genomic location of the sequenced strain Y. enterocolitica biotype 1B, serotype O : 8 strain 8081. Evidence for the functionality of the O : 9 Flag-2 genes, probably located within the plasticity zone of the genome, is provided by swarming assays. PCR analysis of 49 strains revealed the presence of Flag-2 genes in biotypes 2-5, but not in biotypes 1A or 1B. Bioluminescence, measured between 6 and 37 degrees C, showed that the expression of all genes located in Flag-2 and in the known flagellar cluster, Flag-1, was highest at approximately 20 degrees C, and that expression of two Flag-2 genes is FlhC-dependent. In a motility assay, a non-motile and a hyper-motile phenotype resulted from knockout mutations of the Flag-1 genes fliS1 and fliT, respectively. Complemented strains validated these results, confirming the regulatory role of FliT.
authors.affiliation: Zentralinstitut für Ernährungs- und Lebensmittelforschung (ZIEL), Abteilung Mikrobiologie, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany.
authors.forename: Geraldine
authors.initials: G
authors.lastname: Bresolin
authors.affiliation: Zentralinstitut für Ernährungs- und Lebensmittelforschung (ZIEL), Abteilung Mikrobiologie, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany.
authors.forename: Janja
authors.initials: J
authors.lastname: Trček
authors.affiliation: Zentralinstitut für Ernährungs- und Lebensmittelforschung (ZIEL), Abteilung Mikrobiologie, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany.
authors.forename: Siegfried
authors.initials: S
authors.lastname: Scherer
authors.affiliation: Zentralinstitut für Ernährungs- und Lebensmittelforschung (ZIEL), Abteilung Mikrobiologie, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany.
authors.forename: Thilo M
authors.initials: TM
authors.lastname: Fuchs
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D003080:Cold Temperature; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D005407:Flagella / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D005816:Genetic Complementation Test; D014644:Genetic Variation; D008124:Locomotion / Q000235:genetics; D018832:Molecular Chaperones / Q000235:genetics; D008969:Molecular Sequence Data; D005810:Multigene Family; D016254:Mutagenesis, Insertional; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology; D015008:Yersinia enterocolitica / Q000235:genetics* / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D018832:Molecular Chaperones; D014157:Transcription Factors; C076734:FliS protein, Bacteria; C076735:fliT protein, Bacteria