GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com

PMID:17675386

From GONUTS
Jump to: navigation, search
Citation

Muff, TJ, Foster, RM, Liu, PJ and Ordal, GW (2007) CheX in the three-phosphatase system of bacterial chemotaxis. J. Bacteriol. 189:7007-13

Abstract

Bacterial chemotaxis involves the regulation of motility by a modified two-component signal transduction system. In Escherichia coli, CheZ is the phosphatase of the response regulator CheY but many other bacteria, including Bacillus subtilis, use members of the CheC-FliY-CheX family for this purpose. While Bacillus subtilis has only CheC and FliY, many systems also have CheX. The effect of this three-phosphatase system on chemotaxis has not been studied previously. CheX was shown to be a stronger CheY-P phosphatase than either CheC or FliY. In Bacillus subtilis, a cheC mutant strain was nearly complemented by heterologous cheX expression. CheX was shown to overcome the DeltacheC adaptational defect but also generally lowered the counterclockwise flagellar rotational bias. The effect on rotational bias suggests that CheX reduced the overall levels of CheY-P in the cell and did not truly replicate the adaptational effects of CheC. Thus, CheX is not functionally redundant to CheC and, as outlined in the discussion, may be more analogous to CheZ.

Links

PubMed PMC2045203 Online version:10.1128/JB.00896-07

Keywords

Bacillus subtilis/genetics; Bacillus subtilis/metabolism; Bacillus subtilis/physiology; Bacterial Proteins/genetics; Bacterial Proteins/metabolism; Bacterial Proteins/physiology; Chemotaxis/genetics; Chemotaxis/physiology; Flagella/chemistry; Flagella/enzymology; Flagella/metabolism; Gene Expression Regulation, Bacterial; Models, Biological; Mutation; Phosphoprotein Phosphatases/genetics; Phosphoprotein Phosphatases/metabolism; Protein Binding/genetics

Significance

Annotations

Gene product Qualifier GO Term Evidence Code with/from Aspect Extension Notes Status

THEMA:CHEX

GO:0006935: chemotaxis

ECO:0000314:

P

Fig 2 compares the phosphatase activity of Chex, FliY, and CheC. The slope represents the Pi release rate/phosphatase (in micrometers). Slope values were 26 ± 2, 19 ± 1, and 1.7 ± 0.1 µM Pi min–1 µM–1 phosphatase for CheX, FliY, and CheC, respectively.

complete


See also

References

See Help:References for how to manage references in GONUTS.