title: Promoter analysis of cytolethal distending toxin genes (cdtA , B, and C ) and effect of a luxS mutation on CDT production in Campylobacter jejuni.
abstract: Quorum sensing is known to be related to regulation of virulence factors in some pathogens. We report transcriptional analysis of cdt genes (cdtA, B, and C ) encoding cytolethal distending toxin (CDT) in Campylobacter jejuni and demonstrate that a luxS mutation affects the cdt transcription in C. jejuni. The reverse transcriptase-polymerase chain reaction (RT-PCR) showed that cdtA, cdtB, and cdtC genes constitute a polycistronic operon in C. jejuni. A putative transcriptional start site was found at 81-bp upstream from the start codon of cdtA by the primer extension assay. A decrease in cdt transcription was observed in the luxS null mutant, which is defective in AI-2 production. The level of cdt transcription in the luxS mutant was approximately 61% of that in the wild-type. Flow cytometric analysis showed that the number of HeLa cells arrested in the G (2) /M phase, a common biological feature of CDT activity, was reduced by treatment with the cell-free supernatant of the luxS mutant as compared to that of the wild-type. Our observations suggest that the function of luxS is related to the regulation of cdt in C. jejuni.
authors: Laboratory of Veterinary Public Health, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Japan.
authors: Byeonghwa
authors: B
authors: Jeon
authors: Kikuji
authors: K
authors: Itoh
authors: Sangryeol
authors: S
authors: Ryu
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001427:Bacterial Toxins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D016123:Campylobacter jejuni / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D013437:Carbon-Sulfur Lyases; D015964:Gene Expression Regulation, Bacterial; D009154:Mutation; D011401:Promoter Regions, Genetic / Q000235:genetics*; D011485:Protein Binding; D021122:Protein Subunits; D015398:Signal Transduction
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D021122:Protein Subunits; C067044:cytolethal distending toxin; D013437:Carbon-Sulfur Lyases; C117753:LuxS protein, Bacteria