A Variable Active Site Residue Influences the Kinetics of Response Regulator Phosphorylation and Dephosphorylation.

ABSTRACT: Two-component regulatory systems, minimally composed of a sensor kinase and a response regulator protein, are common mediators of signal transduction in microorganisms. All response regulators contain a receiver domain with conserved active site residues that catalyze the signal activating and deactivating phosphorylation and dephosphorylation reactions. We explored the impact of variable active site position T+1 (one residue C-terminal to the conserved Thr/Ser) on reaction kinetics and signaling fidelity, using wild type and mutant Escherichia coli CheY, CheB, and NarL to represent the three major sequence classes observed across response regulators: Ala/Gly, Ser/Thr, and Val/Ile/Met, respectively, at T+1. Biochemical and structural data together suggested that different amino acids at T+

SUBMITTER: Immormino RM 

PROVIDER: S-EPMC5050157 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature