CheB localizes to polar receptor arrays during repellent adaptation.

Adaptation of the response to stimuli is a fundamental process for all organisms. Here, we show that the adaptation enzyme CheB methylesterase of assembles to the ON state receptor array after exposure to the repellent l-isoleucine and dissociates from the array after adaptation is complete. The duration of increased CheB localization and the time of highly clockwise-biased flagellar rotation were similar and depended on the strength of the stimulus.