title: Gene inactivation of a chemotaxis operon in the pathogen Leptospira interrogans.
abstract: Chemotaxis may have an important role in the infection process of pathogenic Leptospira spp.; however, little is known about the regulation of flagellar-based motility in these atypical bacteria. We generated a library of random transposon mutants of the pathogen L. interrogans, which included a mutant with insertion in the first gene of an operon containing the chemotaxis genes cheA, cheW, cheD, cheB, cheY and mcp. The disrupted gene encodes a putative histidine kinase (HK). The HK mutant was motile and virulent, but swarm plate and capillary assays suggested that chemotaxis was reduced in this mutant. Further analysis of bacterial trajectories by videomicroscopy showed that the ability of this mutant to reverse was significantly impaired in comparison to wild-type strain. Our data therefore show that this operon is required for full chemotaxis of Leptospira spp.
authors: Institut Pasteur, Unité de Biologie des Spirochètes, 75724 Paris Cedex 15, France.
authors: Ambroise
authors: A
authors: Lambert
authors: Institut Pasteur, Unité de Physique des Systèmes Biologiques, 75724 Paris Cedex 15, France.
authors: Jérôme
authors: J
authors: Wong Ng
authors: Institut Pasteur, Unité de Biologie des Spirochètes, 75724 Paris Cedex 15, France mathieu.picardeau@pasteur.fr.
authors: Mathieu
authors: M
authors: Picardeau
mesh_terms: D000818:Animals; D002633:Chemotaxis / Q000235:genetics*; D004251:DNA Transposable Elements; D020868:Gene Silencing; D005849:Gerbillinae; D000071677:Histidine Kinase; D007921:Leptospira interrogans / Q000235:genetics* / Q000502:physiology; D007922:Leptospirosis / Q000382:microbiology; D008297:Male; D018715:Microscopy, Video; D009154:Mutation; D009876:Operon; D011494:Protein Kinases / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D004251:DNA Transposable Elements; D011494:Protein Kinases; D000071677:Histidine Kinase
keywords: Leptospira; chemotaxis; motility