Coupling between ATP hydrolysis and protein conformational change in maltose transporter.
Proteins
; 85(2): 207-220, 2017 02.
Article
em En
| MEDLINE
| ID: mdl-27616441
ABSTRACT
As the intracellular part of maltose transporter, MalK dimer utilizes the energy of ATP hydrolysis to drive protein conformational change, which then facilitates substrate transport. Free energy evaluation of the complete conformational change before and after ATP hydrolysis is helpful to elucidate the mechanism of chemical-to-mechanical energy conversion in MalK dimer, but is lacking in previous studies. In this work, we used molecular dynamics simulations to investigate the structural transition of MalK dimer among closed, semi-open and open states. We observed spontaneous structural transition from closed to open state in the ADP-bound system and partial closure of MalK dimer from the semi-open state in the ATP-bound system. Subsequently, we calculated the reaction pathways connecting the closed and open states for the ATP- and ADP-bound systems and evaluated the free energy profiles along the paths. Our results suggested that the closed state is stable in the presence of ATP but is markedly destabilized when ATP is hydrolyzed to ADP, which thus explains the coupling between ATP hydrolysis and protein conformational change of MalK dimer in thermodynamics. Proteins 2017; 85207-220. © 2016 Wiley Periodicals, Inc.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Trifosfato de Adenosina
/
Transportadores de Cassetes de Ligação de ATP
/
Proteínas de Escherichia coli
/
Escherichia coli
Idioma:
En
Revista:
Proteins
Assunto da revista:
BIOQUIMICA
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
China