Sensor histidine kinase NarQ activates via helical rotation, diagonal scissoring, and eventually piston-like shifts

0563846 - FZÚ 2023 RIV CH eng J - Journal Article
Gushchin, I. - Orekhov, P. - Melnikov, I. - Polovinkin, Vitaly - Yuzhakova, A. - Gordeliy, V.
Sensor histidine kinase NarQ activates via helical rotation, diagonal scissoring, and eventually piston-like shifts.
International Journal of Molecular Sciences. Roč. 21, č. 9 (2020), č. článku 3110. E-ISSN 1422-0067
Institutional support: RVO:68378271
Keywords : two-component systems * histidine kinase * receptor * transmembrane signaling * X-ray crystallography * molecular dynamics
OECD category: Biophysics
Impact factor: 5.924, year: 2020
Method of publishing: Open access

Membrane-embedded sensor histidine kinases (HKs) and chemoreceptors are used ubiquitously by bacteria and archaea to percept the environment. Several mechanisms of transmembrane signal transduction in TCS receptors have been proposed, dubbed (swinging) piston, helical rotation, and diagonal scissoring. We extend our previous work on Escherichia coli nitrate/nitrite sensor kinase NarQ. We determined a crystallographic structure of the sensor-TM-HAMP fragment of the R50S mutant, which, unexpectedly, was found in a ligand-bound-like conformation, despite an inability to bind nitrate. Subsequently, we reanalyzed the structures of the ligand-free and ligand-bound NarQ and NarX sensor domains, and conducted extensive molecular dynamics simulations of ligand-free and ligand-bound wild type and mutated NarQ. Based on the data, we show that binding of nitrate to NarQ causes, first and foremost, helical rotation and diagonal scissoring of the α-helices at the core of the sensor domain.
Permanent Link: https://hdl.handle.net/11104/0335635