Rational modulation of the enzymatic intermediates for tuning the phosphatase activity of histidine kinase HK853

Biochem Biophys Res Commun. 2020 Mar 12;523(3):733-738. doi: 10.1016/j.bbrc.2020.01.036. Epub 2020 Jan 14.

Abstract

Histidine kinase (HK) of two-component signal transduction system (TCS) is a potential drug target for treating bacterial infections, and most HKs are bifunctional. We have previously identified the HXXXT motif of HK in HisKA subfamily to perform the phosphatase activity, but the specific working mechanism of the threonine is not well understood. In this paper, we use the phosphate group analog BeF3- to capture the enzymatic intermediates between HK853 and RR468 from Thermotoga maritima during dephosphorylation, and demonstrate that the T264 site is essential for populating capable near attack conformers (NAC) between enzyme and substrate to facilitate catalysis. Importantly, mutations at this site can modulate the phosphatase activity of HK. Our results help to understand the TCS signal transduction mechanisms and provide a reference for drug design.

Keywords: Dynamics; Histidine kinase; Near attack conformation; Phosphatase; Two-component system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs
  • Histidine / metabolism
  • Histidine Kinase / chemistry
  • Histidine Kinase / metabolism*
  • Molecular Dynamics Simulation
  • Phosphoric Monoester Hydrolases / chemistry
  • Phosphoric Monoester Hydrolases / metabolism*
  • Protein Conformation
  • Substrate Specificity
  • Thermotoga maritima / chemistry
  • Thermotoga maritima / enzymology*
  • Thermotoga maritima / metabolism

Substances

  • Histidine
  • Histidine Kinase
  • Phosphoric Monoester Hydrolases