This Article Full Text (PDF) Other Versions of this Article: JB.01807-06v1 189/15/5683    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by De Silva, R. S. Articles by Kull, F. J. Search for Related Content PubMed PubMed Citation Articles by De Silva, R. S. Articles by Kull, F. J.

 Previous Article  |  Next Article 

J. Bacteriol. doi:10.1128/JB.01807-06
Copyright (c) 2007, American Society for Microbiology and/or the Listed Authors/Institutions. All Rights Reserved.

Crystal structure of the Vibrio cholerae Quorum Sensing Regulatory Protein HapR

Department of Chemistry, Dartmouth College and Department of Microbiology and Immunology, Dartmouth Medical School, Hanover, New Hampshire 03755

^* To whom correspondence should be addressed. Email: f.jon.kull{at}dartmouth.edu.

	Abstract

Quorum sensing in Vibrio cholerae involves signaling between two-component sensor protein kinases and the response regulator LuxO to control the expression of the master regulator HapR. HapR, in turn, plays a central role in regulating a number of important processes, such as virulence gene expression and biofilm formation. We have determined the crystal structure of HapR to 2.2 Å resolution. Its structure reveals a dimeric, two domain molecule with an all helical structure that is strongly conserved with members of the TetR family of transcriptional regulators. The N-terminal DNA-binding domain contains a helix-turn-helix DNA-binding motif and alteration of certain residues in this domain completely abolishes the ability of HapR to bind to DNA, alleviating repression of both virulence gene expression and biofilm formation. The C-terminal dimerization domain contains a unique solvent accessible tunnel connected to an amphipathic cavity, which by analogy with other TetR regulators, may serve as a binding pocket for an as yet unidentified ligand.

This article has been cited by other articles:

• Lee, D. H., Jeong, H. S., Jeong, H. G., Kim, K. M., Kim, H., Choi, S. H. (2008). A Consensus Sequence for Binding of SmcR, a Vibrio vulnificus LuxR Homologue, and Genome-wide Identification of the SmcR Regulon. J. Biol. Chem. 283: 23610-23618 [Abstract] [Full Text]  
• Waters, C. M., Lu, W., Rabinowitz, J. D., Bassler, B. L. (2008). Quorum Sensing Controls Biofilm Formation in Vibrio cholerae through Modulation of Cyclic Di-GMP Levels and Repression of vpsT. J. Bacteriol. 190: 2527-2536 [Abstract] [Full Text]  
• Svenningsen, S. L., Waters, C. M., Bassler, B. L. (2008). A negative feedback loop involving small RNAs accelerates Vibrio cholerae's transition out of quorum-sensing mode. Genes Dev. 22: 226-238 [Abstract] [Full Text]