phosphoacceptor receiver (REC) domain of chemotaxis protein CheY
The chemotaxis response regulator CheY contains a stand-alone REC domain. Chemotaxis is a behavior known for motile bacteria that directs their movement in response to chemical gradients. CheY is involved in transmitting sensory signals from chemoreceptors to the flagellar motors. Phosphorylated CheY interacts with the flagella switch components FliM and FliY, which causes counterclockwise rotation of the flagella, resulting in smooth swimming. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.
Comment:signal transduction in two-component systems is mediated by metal ion dependent phosphorelay reactions between protein histidine kinases and phosphoaccepting receiver domains in response regulator proteins
Comment:for many receivers, Mg2+ is the preferred metal ion, but other divalent ions such as Mn2+ are also used
Comment:partly based on metal binding site of other family members
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