CheZ Has No Effect on Flagellar Motors Activated by CheY13DK106YW
AUTOR(ES)
Scharf, Birgit E.
FONTE
American Society for Microbiology
RESUMO
The behaviors of both cheZ-deleted and wild-type cells of Escherichia coli were found to be very sensitive to the level of expression of CheZ, a protein known to accelerate the dephosphorylation of the response regulator CheY-phosphate (CheY-P). However, cells induced to run and tumble by the unphosphorylated mutant protein CheY13DK106YW (CheY**) failed to respond to CheZ, even when CheZ was expressed at high levels. Therefore, CheZ neither affects the flagellar motors directly nor sequesters CheY**. In in vitro cross-linking studies, CheY** promoted trimerization of CheZ to the same extent as wild-type CheY but failed to induce the formation of complexes of higher molecular weight observed with CheY-P. Also, CheY** could be cross-linked to FliM, the motor receptor protein, nearly as well as CheY-P. Thus, to CheZ, CheY** looks like CheY, but to FliM, it looks like CheY-P.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=107548Documentos Relacionados
- Roles of cheY and cheZ gene products in controlling flagellar rotation in bacterial chemotaxis of Escherichia coli.
- Signal termination in bacterial chemotaxis: CheZ mediates dephosphorylation of free rather than switch-bound CheY.
- A chemotactic signaling surface on CheY defined by suppressors of flagellar switch mutations.
- CheZ-Mediated Dephosphorylation of the Escherichia coli Chemotaxis Response Regulator CheY: Role for CheY Glutamate 89†
- Regulation of Switching Frequency and Bias of the Bacterial Flagellar Motor by CheY and Fumarate