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Title: Effect of salt identity on the phase diagram for a globularprotein in aqueous electrolyte solution

Abstract

Monte Carlo simulations are used to establish the potential of mean force between two globular proteins in an aqueous electrolyte solution. This potential includes nonelectrostatic contributions arising from dispersion forces first, between the globular proteins, and second, between ions in solution and between each ion and the globular protein. These latter contributions are missing from standard models. The potential of mean force, obtained from simulation, is fitted to an analytic equation. Using our analytic potential of mean force and Barker-Henderson perturbation theory, we obtain phase diagrams for lysozyme solutions that include stable and metastable fluid-fluid and solid-fluid phases when the electrolyte is 0.2 M NaSCN or NaI or NaCl. The nature of the electrolyte has a significant effect on the phase diagram.

Authors:
; ; ;
Publication Date:
Research Org.:
COLLABORATION - LinkopingU./Sweden
Sponsoring Org.:
USDOE Director. Office of Science. Office of Basic EnergySciences
OSTI Identifier:
919763
Report Number(s):
LBNL-59857
Journal ID: ISSN 1089-5647; JPCBFK; R&D Project: 402201; BnR: KC0302040; TRN: US200822%%527
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry B; Journal Volume: 110; Journal Issue: 48; Related Information: Journal Publication Date: 11/07/2006
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; ELECTROLYTES; LYSOZYME; PERTURBATION THEORY; PHASE DIAGRAMS; PROTEINS; SIMULATION

Citation Formats

Bostrom, Mathias, Tavares, Frederico W., Ninham, Barry W., and Prausnitz, John M. Effect of salt identity on the phase diagram for a globularprotein in aqueous electrolyte solution. United States: N. p., 2006. Web. doi:10.1021/jp061191g.
Bostrom, Mathias, Tavares, Frederico W., Ninham, Barry W., & Prausnitz, John M. Effect of salt identity on the phase diagram for a globularprotein in aqueous electrolyte solution. United States. doi:10.1021/jp061191g.
Bostrom, Mathias, Tavares, Frederico W., Ninham, Barry W., and Prausnitz, John M. Wed . "Effect of salt identity on the phase diagram for a globularprotein in aqueous electrolyte solution". United States. doi:10.1021/jp061191g. https://www.osti.gov/servlets/purl/919763.
@article{osti_919763,
title = {Effect of salt identity on the phase diagram for a globularprotein in aqueous electrolyte solution},
author = {Bostrom, Mathias and Tavares, Frederico W. and Ninham, Barry W. and Prausnitz, John M.},
abstractNote = {Monte Carlo simulations are used to establish the potential of mean force between two globular proteins in an aqueous electrolyte solution. This potential includes nonelectrostatic contributions arising from dispersion forces first, between the globular proteins, and second, between ions in solution and between each ion and the globular protein. These latter contributions are missing from standard models. The potential of mean force, obtained from simulation, is fitted to an analytic equation. Using our analytic potential of mean force and Barker-Henderson perturbation theory, we obtain phase diagrams for lysozyme solutions that include stable and metastable fluid-fluid and solid-fluid phases when the electrolyte is 0.2 M NaSCN or NaI or NaCl. The nature of the electrolyte has a significant effect on the phase diagram.},
doi = {10.1021/jp061191g},
journal = {Journal of Physical Chemistry B},
number = 48,
volume = 110,
place = {United States},
year = {Wed Feb 22 00:00:00 EST 2006},
month = {Wed Feb 22 00:00:00 EST 2006}
}
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