English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/128841
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:

The mechanism of water/ion exchange at a protein surface: a weakly bound chloride in Helicobacter pylori apoflavodoxin

AutorGalano-Frutos, Juan J.; Morón, M. Carmen; Sancho, Javier
Fecha de publicación2015
EditorRoyal Society of Chemistry (Great Britain)
CitaciónPhysical Chemistry Chemical Physics 17(43): 28635-28646 (2015)
ResumenBinding/unbinding of small ligands, such as ions, to/from proteins influences biochemical processes such as protein folding, enzyme catalysis or protein/ligand recognition. We have investigated the mechanism of chloride/water exchange at a protein surface (that of the apoflavodoxin from Helicobacter pylori) using classical all-atom molecular dynamics simulations. They reveal a variety of chloride exit routes and residence times; the latter is related to specific coordination modes of the anion. The role of solvent molecules in the mechanism of chloride unbinding has been studied in detail. We see no temporary increase in chloride coordination along the release process. Instead, the coordination of new water molecules takes place in most cases after the chloride/protein atom release event has begun. Moreover, the distribution function of water entrance events into the first chloride solvation shell peaks after chloride protein atom dissociation events. All these observations together seem to indicate that water molecules simply fill the vacancies left by the previously coordinating protein residues. We thus propose a step-by-step dissociation pathway in which protein/chloride interactions gradually break down before new water molecules progressively fill the vacant positions left by protein atoms. As observed for other systems, water molecules associated with bound chloride or with protein atoms have longer residence times than those bound to the free anion. The implications of the exchange mechanism proposed for the binding of the FMN (Flavin Mononucleotide) protein cofactor are discussed.
Versión del editorhttp://dx.doi.org/10.1039/c5cp04504e
Identificadoresdoi: 10.1039/c5cp04504e
issn: 1463-9076
e-issn: 1463-9084
Aparece en las colecciones: (ICMA) Artículos
(IQFR) Artículos
Ficheros en este ítem:
Fichero Descripción Tamaño Formato  
Moron_postprint_PccP.pdf1,54 MBAdobe PDFVista previa
Moron_supplementary_postprint_Pccp.pdf2,09 MBAdobe PDFVista previa
Mostrar el registro completo

NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.