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Title: Reconstruction of the Chemotaxis Receptor-Kinase Assembly

Abstract

In bacterial chemotaxis, an assembly of transmembrane receptors, the CheA histidine kinase and the adaptor protein CheW processes environmental stimuli to regulate motility. The structure of a Thermotoga maritima receptor cytoplasmic domain defines CheA interaction regions and metal ion-coordinating charge centers that undergo chemical modification to tune receptor response. Dimeric CheA-CheW, defined by crystallography and pulsed ESR, positions two CheWs to form a cleft that is lined with residues important for receptor interactions and sized to clamp one receptor dimer. CheW residues involved in kinase activation map to interfaces that orient the CheW clamps. CheA regulatory domains associate in crystals through conserved hydrophobic surfaces. Such CheA self-contacts align the CheW receptor clamps for binding receptor tips. Linking layers of ternary complexes with close-packed receptors generates a lattice with reasonable component ratios, cooperative interactions among receptors and accessible sites for modification enzymes.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
914150
Report Number(s):
BNL-78718-2007-JA
TRN: US0801577
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nat. Struct. Mol. Biol.; Journal Volume: 13; Journal Issue: 5
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; CRYSTALLOGRAPHY; ENZYMES; HISTIDINE; MODIFICATIONS; PHOSPHOTRANSFERASES; PROTEINS; RESIDUES; STIMULI; NSLS; national synchrotron light source

Citation Formats

Park,S., Borbat, P., Gonzalez-Bonet, G., Bhatnagar, J., Pollard, A., Freed, J., Bilwes, A., and Crane, B. Reconstruction of the Chemotaxis Receptor-Kinase Assembly. United States: N. p., 2006. Web. doi:10.1038/nsmb1085.
Park,S., Borbat, P., Gonzalez-Bonet, G., Bhatnagar, J., Pollard, A., Freed, J., Bilwes, A., & Crane, B. Reconstruction of the Chemotaxis Receptor-Kinase Assembly. United States. doi:10.1038/nsmb1085.
Park,S., Borbat, P., Gonzalez-Bonet, G., Bhatnagar, J., Pollard, A., Freed, J., Bilwes, A., and Crane, B. Sun . "Reconstruction of the Chemotaxis Receptor-Kinase Assembly". United States. doi:10.1038/nsmb1085.
@article{osti_914150,
title = {Reconstruction of the Chemotaxis Receptor-Kinase Assembly},
author = {Park,S. and Borbat, P. and Gonzalez-Bonet, G. and Bhatnagar, J. and Pollard, A. and Freed, J. and Bilwes, A. and Crane, B.},
abstractNote = {In bacterial chemotaxis, an assembly of transmembrane receptors, the CheA histidine kinase and the adaptor protein CheW processes environmental stimuli to regulate motility. The structure of a Thermotoga maritima receptor cytoplasmic domain defines CheA interaction regions and metal ion-coordinating charge centers that undergo chemical modification to tune receptor response. Dimeric CheA-CheW, defined by crystallography and pulsed ESR, positions two CheWs to form a cleft that is lined with residues important for receptor interactions and sized to clamp one receptor dimer. CheW residues involved in kinase activation map to interfaces that orient the CheW clamps. CheA regulatory domains associate in crystals through conserved hydrophobic surfaces. Such CheA self-contacts align the CheW receptor clamps for binding receptor tips. Linking layers of ternary complexes with close-packed receptors generates a lattice with reasonable component ratios, cooperative interactions among receptors and accessible sites for modification enzymes.},
doi = {10.1038/nsmb1085},
journal = {Nat. Struct. Mol. Biol.},
number = 5,
volume = 13,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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