JB
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Givaudan, A.
Right arrow Articles by Lanois, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Givaudan, A.
Right arrow Articles by Lanois, A.

 Previous Article  |  Next Article 

Journal of Bacteriology, January 2000, p. 107-115, Vol. 182, No. 1
0021-9193/0/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.

flhDC, the Flagellar Master Operon of Xenorhabdus nematophilus: Requirement for Motility, Lipolysis, Extracellular Hemolysis, and Full Virulence in Insects

Alain Givaudan* and Anne Lanois

Laboratoire de Pathologie Comparée, Université Montpellier II, IFR 56, Institut National de la Recherche Agronomique-Centre National de la Recherche Scientifique (URA 2209), 34095 Montpellier Cedex 05, France

Received 26 July 1999/Accepted 14 October 1999

Xenorhabdus is a major insect pathogen symbiotically associated with nematodes of the family Steinernematidae. This motile bacterium displays swarming behavior on suitable media, but a spontaneous loss of motility is observed as part of a phenomenon designated phase variation which involves the loss of stationary-phase products active as antibiotics and potential virulence factors. To investigate the role of one of the transcriptional activators of flagellar genes, FlhDC, in motility and virulence, the Xenorhabdus nematophilus flhDC locus was identified by functional complementation of an Escherichia coli flhD null mutant and DNA sequencing. Construction of X. nematophilus flhD null mutants confirmed that the flhDC operon controls flagellin expression but also revealed that lipolytic and extracellular hemolysin activity is flhDC dependent. We also showed that the flhD null mutant displayed a slightly attenuated virulence phenotype in Spodoptera littoralis compared to that of the wild-type strain. Thus, these data indicated that motility, lipase, hemolysin, or unknown functions controlled by the flhDC operon are involved in the infectious process in insects. Our investigation expands the view of the flagellar regulon as a checkpoint coupled to a major network involving bacterial physiological aspects as well as motility.

* Corresponding author. Mailing address: Laboratoire de Pathologie Comparée, Université Montpellier II, INRA-CNRS (URA 2209), CP101, Place E. Bataillon, 34095 Montpellier Cedex 05, France. Phone: (33) 4 67 14 48 12. Fax: (33) 4 67 14 46 79. E-mail: givaudan{at}crit.univ-montp2.fr.

Journal of Bacteriology, January 2000, p. 107-115, Vol. 182, No. 1
0021-9193/0/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Appl. Environ. Microbiol. Infect. Immun. Eukaryot. Cell
Mol. Cell. Biol. J. Virol. Microbiol. Mol. Biol. Rev.
ALL ASM JOURNALS

Copyright © 2000 by the American Society for Microbiology. All rights reserved.