Molecular simulations of dodecyl-β-maltoside micelles in water: influence of the headgroup conformation and force field parameters.

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TitleMolecular simulations of dodecyl-β-maltoside micelles in water: influence of the headgroup conformation and force field parameters.
Publication TypeJournal Article
Year of Publication2011
AuthorsAbel, S, Dupradeau, F-Y, E Raman, P, Mackerell, AD, Marchi, M
JournalJ Phys Chem B
Volume115
Issue3
Pagination487-99
Date Published2011 Jan 27
ISSN1520-5207
KeywordsDetergents, Glucosides, Micelles, Models, Molecular, Molecular Conformation, Molecular Dynamics Simulation, Molecular Structure, Software, Water
Abstract

This paper deals with the development and validation of new potential parameter sets, based on the CHARMM36 and GLYCAM06 force fields, to simulate micelles of the two anomeric forms (α and β) of N-dodecyl-β-maltoside (C(12)G(2)), a surfactant widely used in the extraction and purification of membrane proteins. In this context, properties such as size, shape, internal structure, and hydration of the C(12)G(2) anomer micelles were thoroughly investigated by molecular dynamics simulations and the results compared with experiments. Additional simulations were also performed with the older CHARMM22 force field for carbohydrates (Kuttel, M.; et al. J. Comput. Chem. 2002, 23, 1236-1243). We find that our CHARMM and GLYCAM parameter sets yield similar results in the case of properties related to the micelle structure but differ for other properties such as the headgroup conformation or the micelle hydration. In agreement with experiments, our results show that for all model potentials the β-C(12)G(2) micelles have a more pronounced ellipsoidal shape than those containing α anomers. The computed radius of gyration is 20.2 and 25.4 Å for the α- and β-anomer micelles, respectively. Finally, we show that depending on the potential the water translational diffusion of the interfacial water is 7-11.5 times slower than that of bulk water due to the entrapment of the water in the micelle crevices. This retardation is independent of the headgroup in α- or β-anomers.

DOI10.1021/jp109545v
Alternate JournalJ Phys Chem B
PubMed ID21192681
PubMed Central IDPMC3076730
Grant ListR01 GM070855 / GM / NIGMS NIH HHS / United States
R01 GM070855-06 / GM / NIGMS NIH HHS / United States
GM070855 / GM / NIGMS NIH HHS / United States