Tethered particle motion of the adaptation enzyme CheR in bacterial chemotaxis.

ABSTRACT: Bacteria perform chemotactic adaptation by sequential modification of multiple modifiable sites on chemoreceptors through stochastic action of tethered adaptation enzymes (CheR and CheB). To study the molecular kinetics of this process, we measured the response to different concentrations of MeAsp for the Tar-only Escherichia coli strain. We found a strong dependence of the methylation rate on the methylation level and established a new mechanism of adaptation kinetics due to tethered particle motion of the methylation enzyme CheR. Experiments with various lengths of the C-terminal flexible chain in the Tar receptor further validated this mechanism. The tethered particle motion resulted in a CheR concentration gradient that ensures encounter-rate matching of the sequential modifiabl

SUBMITTER: Yue C 

PROVIDER: S-EPMC10561060 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature