Isolation and in vitro characterization of CheZ suppressors for the Escherichia coli chemotactic response regulator mutant CheYN23D.

CobB regulates Escherichia coli chemotaxis by deacetylating the response regulator CheY

The silent information regulator (Sir2) family proteins are NAD+-dependent deacetylases. Although a few substrates have been identified, functions of the bacteria Sir2-like protein (CobB) still remain unclear. Here the role of CobB on Escherichia coli chemotaxis was investigated. We used Western blotting and mass spectrometry to show that the response regulator CheY is a substrate of CobB. Surf...

Interactions between chemotaxis genes and flagellar genes in Escherichia coli.

Escherichia coli mutants defective in cheY and cheZ function are motile but generally nonchemotactic; cheY mutants have an extreme counterclockwise bias in flagellar rotation, whereas cheZ mutants have a clockwise rotational bias. Chemotactic pseudorevertants of cheY and cheZ mutants were isolated on semisolid agar and examined for second-site suppressors in other chemotaxis-related loci. Appro...

Interaction of the cheC and cheZ gene products is required for chemotactic behavior in Escherichia coli.

Previous work has shown that the cheC gene product of Escherichia coli plays a key role in regulating the direction of flagellar rotation during chemotactic responses. An attempt was made to identify other stimulus transduction elements that interact with the cheC component by examining cheC revertants for functional suppressors. Approximately two-thirds of the revertants studied appeared to be...

Isolation, Identification and in vitro Susceptibility of Avian Escherichia coli to Selected Fluoroquinolones

In vivo and in vitro characterization of Escherichia coli protein CheZ gain- and loss-of-function mutants.

Bacterial chemotaxis results from the ability of flagellated bacteria to control the frequency of switching between smooth-swimming and tumbling episodes in response to changes in concentration of extracellular substances. High levels of phosphorylated CheY protein are the intracellular signal for inducing the tumbling mode of swimming. The CheZ protein has been shown to control the level of ph...