Quorum sensing regulates type III secretion in Vibrio harveyi and Vibrio parahaemolyticus.

TitleQuorum sensing regulates type III secretion in Vibrio harveyi and Vibrio parahaemolyticus.
Publication TypeJournal Article
Year of Publication2004
AuthorsHenke, JM, Bassler, BL
JournalJ Bacteriol
Date Published2004 Jun
Keywords4-Butyrolactone, Bacterial Proteins, Culture Media, Conditioned, Gene Expression Regulation, Bacterial, Luminescent Measurements, Molecular Sequence Data, Multigene Family, Repressor Proteins, Sequence Analysis, DNA, Signal Transduction, Transcription, Genetic, Vibrio, Vibrio parahaemolyticus

<p>In a process known as quorum sensing, bacteria communicate with one another by producing, releasing, detecting, and responding to signal molecules called autoinducers. Vibrio harveyi, a marine pathogen, uses two parallel quorum-sensing circuits, each consisting of an autoinducer-sensor pair, to control the expression of genes required for bioluminescence and a number of other target genes. Genetic screens designed to discover autoinducer-regulated targets in V. harveyi have revealed genes encoding components of a putative type III secretion (TTS) system. Using transcriptional reporter fusions and TTS protein localization studies, we show that the TTS system is indeed functional in V. harveyi and that expression of the genes encoding the secretion machinery requires an intact quorum-sensing signal transduction cascade. The newly completed genome of the closely related marine bacterium Vibrio parahaemolyticus, which is a human pathogen, shows that it possesses the genes encoding both of the V. harveyi-like quorum-sensing signaling circuits and that it also has a TTS system similar to that of V. harveyi. We show that quorum sensing regulates TTS in V. parahaemolyticus. Previous reports connecting quorum sensing to TTS in enterohemorrhagic and enteropathogenic Escherichia coli show that quorum sensing activates TTS at high cell density. Surprisingly, we find that at high cell density (in the presence of autoinducers), quorum sensing represses TTS in V. harveyi and V. parahaemolyticus.</p>

Alternate JournalJ Bacteriol
PubMed ID15175293
PubMed Central IDPMC419960
Grant ListR01 GM065859 / GM / NIGMS NIH HHS / United States
R01 GM 065859 / GM / NIGMS NIH HHS / United States