OpaR, a Homolog of Vibrio harveyi LuxR, Controls Opacity of Vibrio parahaemolyticus
AUTOR(ES)
McCarter, Linda L.
FONTE
American Society for Microbiology
RESUMO
Vibrio parahaemolyticus is an organism well adapted to communal life on surfaces. When grown on a surface or in a viscous layer, the bacterium induces a large gene system and differentiates to swarmer cells capable of movement over and colonization of surfaces. V. parahaemolyticus displays additional phenotypic versatility manifested as variable colony morphology, switching between translucent and opaque colony types. Although not itself luminescent, V. parahaemolyticus produces autoinducer molecules capable of inducing luminescence in Vibrio harveyi. To examine the role of quorum signaling in the lifestyles of V. parahaemolyticus, the functional homolog of the gene encoding the V. harveyi autoinducer-controlled transcriptional regulatory protein LuxR was cloned. Sequence analysis of the clone predicted an open reading frame with a deduced product 96% identical to LuxR. Introduction of the clone carrying the luxR-like locus into V. parahaemolyticus dramatically affected colony morphology, converting a translucent strain to an opaque one. When the coding sequence for the luxR homolog was placed under the control of the Ptac promoter, conversion to the opaque phenotype became inducible by isopropyl-β-d-thiogalactopyranoside. Allelic disruption of the luxR-like gene on the chromosome of an opaque strain produced a translucent strain proficient in swarming ability. Primer extension mapping demonstrated opaR transcription in opaque but not translucent cell types. It is postulated that this gene, which has been named opaR, encodes a transcription factor controlling cell type. The underlying genetic basis for opaque-translucent variation may be the consequence of a genomic alteration detected in the opaR locus of opaque and translucent strains.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=107818Documentos Relacionados
- Cloning and nucleotide sequence of luxR, a regulatory gene controlling bioluminescence in Vibrio harveyi.
- VanT, a Homologue of Vibrio harveyi LuxR, Regulates Serine, Metalloprotease, Pigment, and Biofilm Production in Vibrio anguillarum
- Conversion of the Vibrio fischeri Transcriptional Activator, LuxR, to a Repressor
- The luxR gene product of Vibrio harveyi is a transcriptional activator of the lux promoter.
- Regulation of Metalloprotease Gene Expression in Vibrio vulnificus by a Vibrio harveyi LuxR Homologue