Binding of the Escherichia coli response regulator CheY to its target measured in vivo by fluorescence resonance energy transfer.

ABSTRACT: In Escherichia coli chemotaxis, signaling depends on modulation of the level of phosphorylation of CheY, a small protein that couples receptors and flagellar motors. Working in vivo, we used fluorescence resonance energy transfer (FRET) to measure the interaction of CheY approximately P with its target, FliM. Binding of CheY approximately P to FliM was found to be much less cooperative than motor switching; however, under the conditions of our experiment, most of the FliM appeared to be in the cytoplasm. We studied signal processing times in the chemotaxis pathway by measuring the changes in CheY approximately P binding to FliM on flash release of caged chemoeffectors. Following sudden addition of attractant, the amount of CheY approximately P bound to FliM decayed exponentially with a rat

SUBMITTER: Sourjik V 

PROVIDER: S-EPMC130518 | biostudies-literature | 2002 Oct

REPOSITORIES: biostudies-literature