Title | Regulation of LuxPQ receptor activity by the quorum-sensing signal autoinducer-2. |
Publication Type | Journal Article |
Year of Publication | 2005 |
Authors | Neiditch, MB, Federle, MJ, Miller, ST, Bassler, BL, Hughson, FM |
Journal | Mol Cell |
Volume | 18 |
Issue | 5 |
Pagination | 507-18 |
Date Published | 2005 May 27 |
ISSN | 1097-2765 |
Keywords | Amino Acid Sequence, Bacterial Proteins, Crystallography, X-Ray, Homoserine, Lactones, Luminescent Proteins, Models, Molecular, Molecular Sequence Data, Multiprotein Complexes, Phosphotransferases, Protein Binding, Protein Conformation, Protein Folding, Signal Transduction, Transcription Factors, Vibrio |
Abstract | <p>The extracellular signaling molecule autoinducer-2 (AI-2) mediates quorum-sensing communication in diverse bacterial species. In marine vibrios, binding of AI-2 to the periplasmic receptor LuxP modulates the activity of the inner membrane sensor kinase LuxQ, transducing the AI-2 information into the cytoplasm. Here, we show that Vibrio harveyi LuxP associates with LuxQ in both the presence and absence of AI-2. The 1.9 A X-ray crystal structure of apoLuxP, complexed with the periplasmic domain of LuxQ, reveals that the latter contains two tandem Per/ARNT/Simple-minded (PAS) folds. Thus, although many prokaryotic PAS folds themselves bind ligands, the LuxQ periplasmic PAS folds instead bind LuxP, monitoring its AI-2 occupancy. Mutations that disrupt the apoLuxP:LuxQ interface sensitize V. harveyi to AI-2, implying that AI-2 binding causes the replacement of one set of LuxP:LuxQ contacts with another. These conformational changes switch LuxQ between two opposing enzymatic activities, each of which conveys information to the cytoplasm about the cell density of the surrounding environment.</p> |
DOI | 10.1016/j.molcel.2005.04.020 |
Alternate Journal | Mol Cell |
PubMed ID | 15916958 |
Grant List | AI-054442 / AI / NIAID NIH HHS / United States GM-065859 / GM / NIGMS NIH HHS / United States |