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 Derzelle, S. Articles by Danchin, A. Search for Related Content PubMed PubMed Citation Articles by Derzelle, S. Articles by Danchin, A.

The PhoP-PhoQ Two-Component Regulatory System of Photorhabdus luminescens Is Essential for Virulence in Insects

Unité de Génétique des Génomes Bactériens,¹ Laboratoire de Génomique des Microorganismes Pathogènes, Institut Pasteur, 75724 Paris Cedex 15,² Laboratoire EMIP, Université Montpellier II, IFR56, Institut National de la Recherche Agronomique (UMR 1133), 34095 Montpellier Cedex 5, France³

Received 11 September 2003/ Accepted 25 November 2003

Photorhabdus luminescens is a symbiont of entomopathogenic nematodes. Analysis of the genome sequence of this organism revealed a homologue of PhoP-PhoQ, a two-component system associated with virulence in intracellular bacterial pathogens. This organism was shown to respond to the availability of environmental magnesium. A mutant with a knockout mutation in the regulatory component of this system (phoP) had no obvious growth defect. It was, however, more motile and more sensitive to antimicrobial peptides than its wild-type parent. Remarkably, the mutation eliminated virulence in an insect model. No insect mortality was observed after injection of a large number of the phoP bacteria, while very small amounts of parental cells killed insect larvae in less than 48 h. At the molecular level, the PhoPQ system mediated Mg²⁺-dependent modifications in lipopolysaccharides and controlled a locus (pbgPE) required for incorporation of 4-aminoarabinose into lipid A. Mg²⁺-regulated gene expression of pbgP1 was absent in the mutant and was restored when phoPQ was complemented in trans. This finding highlights the essential role played by PhoPQ in the virulence of an entomopathogen.

This article has been cited by other articles:

• Goldman, S. R., Tu, Y., Goldberg, M. B. (2008). Differential Regulation by Magnesium of the Two MsbB Paralogs of Shigella flexneri. J. Bacteriol. 190: 3526-3537 [Abstract] [Full Text]  
• Wang, W.-B., Chen, I-C., Jiang, S.-S., Chen, H.-R., Hsu, C.-Y., Hsueh, P.-R., Hsu, W.-B., Liaw, S.-J. (2008). Role of RppA in the Regulation of Polymyxin B Susceptibility, Swarming, and Virulence Factor Expression in Proteus mirabilis. Infect. Immun. 76: 2051-2062 [Abstract] [Full Text]  
• Kindrachuk, J., Paur, N., Reiman, C., Scruten, E., Napper, S. (2007). The PhoQ-Activating Potential of Antimicrobial Peptides Contributes to Antimicrobial Efficacy and Is Predictive of the Induction of Bacterial Resistance. Antimicrob. Agents Chemother. 51: 4374-4381 [Abstract] [Full Text]  
• Krin, E., Chakroun, N., Turlin, E., Givaudan, A., Gaboriau, F., Bonne, I., Rousselle, J.-C., Frangeul, L., Lacroix, C., Hullo, M.-F., Marisa, L., Danchin, A., Derzelle, S. (2006). Pleiotropic Role of Quorum-Sensing Autoinducer 2 in Photorhabdus luminescens.. Appl. Environ. Microbiol. 72: 6439-6451 [Abstract] [Full Text]  
• Ramos, J. L., Martinez-Bueno, M., Molina-Henares, A. J., Teran, W., Watanabe, K., Zhang, X., Gallegos, M. T., Brennan, R., Tobes, R. (2005). The TetR Family of Transcriptional Repressors. Microbiol. Mol. Biol. Rev. 69: 326-356 [Abstract] [Full Text]  
• Bishop, R. E., Kim, S.-H., El Zoeiby, A. (2005). Role of lipid A palmitoylation in bacterial pathogenesis. Innate Immunity 11: 174-180 [Abstract]  
• Winfield, M. D., Latifi, T., Groisman, E. A. (2005). Transcriptional Regulation of the 4-Amino-4-deoxy-L-arabinose Biosynthetic Genes in Yersinia pestis. J. Biol. Chem. 280: 14765-14772 [Abstract] [Full Text]  
• Bennett, H. P. J., Clarke, D. J. (2005). The pbgPE operon in Photorhabdus luminescens Is Required for Pathogenicity and Symbiosis. J. Bacteriol. 187: 77-84 [Abstract] [Full Text]  
• Marceau, M., Sebbane, F., Ewann, F., Collyn, F., Lindner, B., Campos, M. A., Bengoechea, J.-A., Simonet, M. (2004). The pmrF polymyxin-resistance operon of Yersinia pseudotuberculosis is upregulated by the PhoP-PhoQ two-component system but not by PmrA-PmrB, and is not required for virulence. Microbiology 150: 3947-3957 [Abstract] [Full Text]  
• Jia, W., Zoeiby, A. E., Petruzziello, T. N., Jayabalasingham, B., Seyedirashti, S., Bishop, R. E. (2004). Lipid Trafficking Controls Endotoxin Acylation in Outer Membranes of Escherichia coli. J. Biol. Chem. 279: 44966-44975 [Abstract] [Full Text]