%0 Journal Article %A Bresolin, Geraldine %A Trček, Janja %A Scherer, Siegfried %A Fuchs, Thilo M. %T Presence of a functional flagellar cluster Flag-2 and low-temperature expression of flagellar genes in Yersinia enterocolitica W22703 %D 2008 %J Microbiology, %V 154 %N 1 %P 196-206 %@ 1465-2080 %R https://doi.org/10.1099/mic.0.2007/008458-0 %K RLU, relative light units %I Microbiology Society, %X 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 °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 °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. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.2007/008458-0