phosphoacceptor receiver (REC) domain of citrate family two-component system response regulators
This family includes Lactobacillus paracasei MaeR, Escherichia coli DcuR and DpiA, Klebsiella pneumoniae CitB, as well as Bacillus DctR, MalR, and CitT. These are all response regulators of two-component systems (TCSs) from the citrate family, and are involved in the transcriptional regulation of genes associated with L-malate catabolism (MaeRK), citrate-specific fermentation (DpiAB, CitAB), plasmid inheritance (DpiAB), anaerobic fumarate respiratory system (DcuRS), and malate transport/utilization (MalKR). REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.
Comment:also based on metal binding site of other family members
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
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