PMID:10748173
| Citation |
Schuster, M, Zhao, R, Bourret, RB and Collins, EJ (2000) Correlated switch binding and signaling in bacterial chemotaxis. J. Biol. Chem. 275:19752-8 |
|---|---|
| Abstract |
In Escherichia coli, swimming behavior is mediated by the phosphorylation state of the response regulator CheY. In its active, phosphorylated form, CheY exhibits enhanced binding to a switch component, FliM, at the flagellar motor, which induces a change from counterclockwise to clockwise flagellar rotation. When Ile(95) of CheY is replaced by a valine, increased clockwise rotation correlates with enhanced binding to FliM. A possible explanation for the hyperactivity of this mutant is that residue 95 affects the conformation of nearby residues that potentially interact with FliM. In order to assess this possibility directly, the crystal structure of CheY95IV was determined. We found that CheY95IV is structurally almost indistinguishable from wild-type CheY. Several other mutants with substitutions at position 95 were characterized to establish the structural requirements for switch binding and clockwise signaling at this position and to investigate a general relationship between the two properties. The various rotational phenotypes of these mutants can be explained solely by the amount of phosphorylated CheY bound to the switch, which was inferred from the phosphorylation properties of the mutant CheY proteins and their binding affinities to FliM. Combined genetic, biochemical, and crystallographic results suggest that residue 95 itself is critical in mediating the surface complementarity between CheY and FliM. |
| Links |
PubMed Online version:10.1074/jbc.M909908199 |
| Keywords |
Bacterial Proteins/chemistry; Bacterial Proteins/metabolism; Chemotaxis; Crystallography, X-Ray; Escherichia coli/cytology; Escherichia coli/metabolism; Flagella; Kinetics; Membrane Proteins/chemistry; Membrane Proteins/metabolism; Molecular Sequence Data; Movement; Mutagenesis; Peptides/metabolism; Phenotype; Phosphorylation; Plasmids; Protein Binding; Protein Conformation; Tyrosine/chemistry |
| edit table |
Significance
You can help EcoliWiki by summarizing why this paper is useful
Useful Materials and Methods
You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.
Annotations
<annotationlinks/>
EcoliWiki Links
Add links to pages that link here (e.g. gene, product, method pages)
References
See Help:References for how to manage references in EcoliWiki.