Conformational and Reaction Dynamic Coupling in Histidine Kinases: Insights from Hybrid QM/MM Simulations.
J Chem Inf Model
; 60(2): 833-842, 2020 02 24.
Article
in En
| MEDLINE
| ID: mdl-31923359
ABSTRACT
Histidine kinases (HK) of bacterial two-component systems represent a hallmark of allosterism in proteins, being able to detect a signal through the sensor domain and transmit this information through the protein matrix to the kinase domain which, once active, autophosphorylates a specific histidine residue. Inactive-to-active transition results in a large conformational change that moves the kinase on top of the histidine. In the present work, we use several molecular simulation techniques (Molecular Dynamics, Hybrid QM/MM, and constant pH molecular dynamics) to study the activation and autophosphorylation reactions in L. plantarum WalK, a cis-acting HK. In agreement with previous results, we show that the chemical step requires tight coupling with the conformational step in order to maintain the histidine phosphoacceptor in the correct tautomeric state, with a reactive δ-nitrogen. During the conformational transition, the kinase domain is never released and walks along the HK helix axis, breaking and forming several conserved residue-based contacts. The phosphate transfer reaction is concerted in the transition state region and is catalyzed through the stabilization of the negative developing charge of transferring phosphate along the reaction.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Quantum Theory
/
Molecular Dynamics Simulation
/
Histidine Kinase
Language:
En
Journal:
J Chem Inf Model
Journal subject:
INFORMATICA MEDICA
/
QUIMICA
Year:
2020
Document type:
Article
Affiliation country:
Argentina