The solute-solvent system: solvent constraints on the conformational dynamics of acetylcholine.

Détails

ID Serval
serval:BIB_22824
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
The solute-solvent system: solvent constraints on the conformational dynamics of acetylcholine.
Périodique
Journal of the American Chemical Society
Auteur⸱e⸱s
Vistoli G., Pedretti A., Villa L., Testa B.
ISSN
0002-7863 (Print)
ISSN-L
0002-7863
Statut éditorial
Publié
Date de publication
2002
Volume
124
Numéro
25
Pages
7472-7480
Langue
anglais
Notes
Publication types: Journal Article
Publication Status: ppublish
Résumé
The objective of this study was to determine if and how a solvent influences internal motions in a solute molecule. Acetylcholine was chosen as the object of study given its interesting molecular structure and major biological significance. Molecular dynamics simulations were carried out in the vacuum (10 ns), water (5 ns), methanol (5 ns), and octanol (1.5 ns). Seven clusters of conformers were identified, namely, +g+g, -g-g, +gt, -gt, t+g, t-g, and tt, where the gauche and trans labels refer to the dihedral angles tau(2) and tau(3), respectively. As expected, the relative proportion of these conformational clusters was highly solvent-dependent and corresponded to a progressive loss of conformational freedom with increasing molecular weight of the solvent. More importantly, the conformational clusters were used to calculate instantaneous and median angular velocity (omega and omega(M), respectively) and instantaneous and median angular acceleration (alpha and alpha(M), respectively). Angular velocity and angular acceleration were both found to decrease markedly with increasing molecular weight of the solvent, i.e., vacuum (epsilon = 1) > water > methanol > octanol. The decrease from the vacuum to octanol was approximately 40% for tau(2) and approximately 60% for tau(3). Such solvent-dependent constraints on a solute's internal motions may be biologically and pharmacologically relevant.
Mots-clé
1-Octanol/chemistry, Acetylcholine/chemistry, Kinetics, Methanol/chemistry, Models, Molecular, Molecular Conformation, Solvents/chemistry, Vacuum, Water/chemistry
Pubmed
Création de la notice
19/11/2007 9:47
Dernière modification de la notice
20/08/2019 12:59
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