2flw
From Proteopedia
Crystal structure of Mg2+ and BeF3- ound CheY in complex with CheZ 200-214 solved from a F432 crystal grown in Hepes (pH 7.5)
Structural highlights
Function[CHEY_SALTY] Involved in the transmission of sensory signals from the chemoreceptors to the flagellar motors. In its active (phosphorylated or acetylated) form, CheY exhibits enhanced binding to a switch component, FliM, at the flagellar motor which induces a change from counterclockwise to clockwise flagellar rotation. Shows autophosphatase activity which is enhanced by CheZ. [CHEZ_SALTY] Plays an important role in bacterial chemotaxis signal transduction pathway by accelerating the dephosphorylation of phosphorylated CheY (CheY-P). Acts on free CheY-P.[1] [2] [3] [4] [5] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedChemotaxis, the environment-specific swimming behavior of a bacterial cell is controlled by flagellar rotation. The steady-state level of the phosphorylated or activated form of the response regulator CheY dictates the direction of flagellar rotation. CheY phosphorylation is regulated by a fine equilibrium of three phosphotransfer activities: phosphorylation by the kinase CheA, its auto-dephosphorylation and dephosphorylation by its phosphatase CheZ. Efficient dephosphorylation of CheY by CheZ requires two spatially distinct protein-protein contacts: tethering of the two proteins to each other and formation of an active site for dephosphorylation. The former involves interaction of phosphorylated CheY with the small highly conserved C-terminal helix of CheZ (CheZ(C)), an indispensable structural component of the functional CheZ protein. To understand how the CheZ(C) helix, representing less than 10% of the full-length protein, ascertains molecular specificity of binding to CheY, we have determined crystal structures of CheY in complex with a synthetic peptide corresponding to 15 C-terminal residues of CheZ (CheZ(200-214)) at resolutions ranging from 2.0 A to 2.3A. These structures provide a detailed view of the CheZ(C) peptide interaction both in the presence and absence of the phosphoryl analog, BeF3-. Our studies reveal that two different modes of binding the CheZ(200-214) peptide are dictated by the conformational state of CheY in the complex. Our structures suggest that the CheZ(C) helix binds to a "meta-active" conformation of inactive CheY and it does so in an orientation that is distinct from the one in which it binds activated CheY. Our dual binding mode hypothesis provides implications for reverse information flow in CheY and extends previous observations on inherent resilience in CheY-like signaling domains. Crystal structures of beryllium fluoride-free and beryllium fluoride-bound CheY in complex with the conserved C-terminal peptide of CheZ reveal dual binding modes specific to CheY conformation.,Guhaniyogi J, Robinson VL, Stock AM J Mol Biol. 2006 Jun 9;359(3):624-45. Epub 2006 Apr 6. PMID:16674976[6] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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