Ligand-induced asymmetry in histidine sensor kinase complex regulates quorum sensing.

TitleLigand-induced asymmetry in histidine sensor kinase complex regulates quorum sensing.
Publication TypeJournal Article
Year of Publication2006
AuthorsNeiditch, MB, Federle, MJ, Pompeani, AJ, Kelly, RC, Swem, DL, Jeffrey, PD, Bassler, BL, Hughson, FM
Date Published2006 Sep 22
KeywordsBacterial Proteins, Cell Membrane, Crystallography, X-Ray, Homoserine, Lactones, Ligands, Light Signal Transduction, Macromolecular Substances, Models, Molecular, Phosphotransferases, Protein Binding, Protein Conformation, Signal Transduction, Transcription Factors, Vibrio

<p>Bacteria sense their environment using receptors of the histidine sensor kinase family, but how kinase activity is regulated by ligand binding is not well understood. Autoinducer-2 (AI-2), a secreted signaling molecule originally identified in studies of the marine bacterium Vibrio harveyi, regulates quorum-sensing responses and allows communication between different bacterial species. AI-2 signal transduction in V. harveyi requires the integral membrane receptor LuxPQ, comprised of periplasmic binding protein (LuxP) and histidine sensor kinase (LuxQ) subunits. Combined X-ray crystallographic and functional studies show that AI-2 binding causes a major conformational change within LuxP, which in turn stabilizes a quaternary arrangement in which two LuxPQ monomers are asymmetrically associated. We propose that formation of this asymmetric quaternary structure is responsible for repressing the kinase activity of both LuxQ subunits and triggering the transition of V. harveyi into quorum-sensing mode.</p>

Alternate JournalCell
PubMed ID16990134
PubMed Central IDPMC3468944
Grant ListAI-054442 / AI / NIAID NIH HHS / United States
F32 GM068371 / GM / NIGMS NIH HHS / United States
GM-065859 / GM / NIGMS NIH HHS / United States