Disease relevance of cheW

• To identify functional similarity between the newly identified R. sphaeroides Che pathway and the methyl-accepting chemotaxis protein (MCP)-dependent pathway in enteric bacteria, the R. sphaeroides cheW gene was expressed in a cheW mutant strain of E. coli and found to complement, causing a partial return to a swarming phenotype [1].
• The cheW gene from Escherichia coli has been cloned an inducible promoter, and the effects of the overproduction of the CheW protein on chemotactic behavior and receptor covalent modification have been examined [2].
• Proteomic mapping of a suppressor of non-chemotactic cheW mutants reveals that Helicobacter pylori contains a new chemotaxis protein [3].

High impact information on cheW

• We found that chemotaxis in the cheW Che+ suppressor depended on both cheY and cheA [3].
• DNA sequencing verified that hp0170 was mutated in the cheW Che+ suppressor, and deletion of this open reading frame in the cheW background nearly recapitulated the Che+ suppressor phenotype [3].
• Plasmids that contain the cheW gene behind a regulatable promoter complement a cheW mutation when the CheW protein is produced at low levels [2].
• However, expression of the cheV2 or cheV3 genes in Escherichia coli resulted in an inhibition of chemotaxis in a wild-type strain, indicating their role in chemotaxis, although these genes were unable to complement isogenic E. coli cheW or cheY mutants [4].

Biological context of cheW

• However, when the CheW protein is greatly overproduced in either a wild-type strain or a cheW mutant, chemotaxis is greatly inhibited, cheW null mutant cells swim smoothly as if they were constantly responding to an attractant [2].

References