This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Park, K.-S. Articles by Honda, T. Search for Related Content PubMed PubMed Citation Articles by Park, K.-S. Articles by Honda, T.

vpaH, a Gene Encoding a Novel Histone-Like Nucleoid Structure-Like Protein That Was Possibly Horizontally Acquired, Regulates the Biogenesis of Lateral Flagella in trh-Positive Vibrio parahaemolyticus TH3996

Department of Bacterial Infections, Research Institute for Microbial Diseases, Osaka University, Yamadaoka 3-1, Suita, Osaka 565-0871, Japan,¹ Faculty of Health and Welfare Science, Okayama Prefectural University, 111, Kuboki, Soja, Okayama 719-1197, Japan²

Received 15 December 2004/ Returned for modification 3 March 2005/ Accepted 3 May 2005

A histone-like nucleoid structure (H-NS) is a major component of the bacterial nucleoid and plays a crucial role in the global gene regulation of enteric bacteria. Here, we cloned and characterized the gene for the H-NS-like protein VpaH in Vibrio parahaemolyticus. vpaH encodes a protein of 134 amino acids that shows approximately 55%, 54%, and 41% identities with VicH in Vibrio cholerae, H-NS in V. parahaemolyticus, and H-NS in Escherichia coli, respectively. The vpaH gene was found in only trh-positive V. parahaemolyticus strains and not in Kanagawa-positive or in trh-negative environmental strains. Moreover, the G+C content of the vpaH gene was 38.6%, which is lower than the average G+C content of the whole genome of this bacterium (45.4%). These data suggest that vpaH was transmitted to trh-possessing V. parahaemolyticus strains by lateral transfer. The vpaH gene was located about 2.6 kb downstream of the trh gene, in the convergent direction of the trh transcription. An in-frame deletion mutant of vpaH lacked motility on semisolid motility assay plates. Western blot analysis and electron microscopy observations revealed that the mutant was deficient in lateral flagella biogenesis, whereas there was no defect in the expression of polar flagella. Additionally, the vpaH mutant showed a decreased adherence to HeLa cells and a decrease in biofilm formation compared with the wild-type strain. Introduction of the vpaH gene in the vpaH-negative strain increased the expression of lateral flagella compared with the wild-type strain. In conclusion, our findings suggest that VpaH affects lateral flagellum biogenesis in trh-positive V. parahaemolyticus strain TH3996.

Editor: V. J. DiRita

This article has been cited by other articles:

• Navarre, W. W., McClelland, M., Libby, S. J., Fang, F. C. (2007). Silencing of xenogeneic DNA by H-NS--facilitation of lateral gene transfer in bacteria by a defense system that recognizes foreign DNA. Genes Dev. 21: 1456-1471 [Abstract] [Full Text]  
• Chatterjee, A., Dutta, P. K., Chowdhury, R. (2007). Effect of Fatty Acids and Cholesterol Present in Bile on Expression of Virulence Factors and Motility of Vibrio cholerae. Infect. Immun. 75: 1946-1953 [Abstract] [Full Text]  
• Bhattacharjee, R. N., Park, K.-S., Kumagai, Y., Okada, K., Yamamoto, M., Uematsu, S., Matsui, K., Kumar, H., Kawai, T., Iida, T., Honda, T., Takeuchi, O., Akira, S. (2006). VP1686, a Vibrio Type III Secretion Protein, Induces Toll-like Receptor-independent Apoptosis in Macrophage through NF-{kappa}B Inhibition. J. Biol. Chem. 281: 36897-36904 [Abstract] [Full Text]