TY - JOUR
T1 - Microscopic Origin of Hysteresis in Water Sorption on Protein Matrices
AU - Kim, Sang Beom
AU - Sparano, Evan M.
AU - Singh, Rakesh S.
AU - Debenedetti, Pablo G.
N1 - Funding Information:
P.G.D. gratefully acknowledges financial support from the National Science Foundation (Grant No. CBET-1263565). The computations were performed at the Terascale Infrastructure for Groundbreaking Research in Engineering and Science (TIGRESS), at Princeton University. This work also used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation (Grant No. ACI-1053575).
Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/3/16
Y1 - 2017/3/16
N2 - Despite the importance of water sorption isotherms for a fundamental understanding of protein-water interactions, the microscopic origin of hysteresis between the adsorption and desorption branches is not well understood. Using our recently developed simulation technique, we compute the water sorption isotherms of two proteins, lysozyme and Trp-cage, a miniprotein. We explicitly compare protein-water interactions in adsorption and desorption processes, by analyzing local hydration in terms of hydrogen bonding, water density, and solvent-accessible surface area. We find that significant differences in hydration behavior between adsorption and desorption manifest themselves at the individual amino acid level, in particular around polar or charged residues. We confirm this observation by demonstrating that Trp-cage’s hysteresis can be significantly reduced by mutating charged residues to alanine, a neutral and nonpolar amino acid.
AB - Despite the importance of water sorption isotherms for a fundamental understanding of protein-water interactions, the microscopic origin of hysteresis between the adsorption and desorption branches is not well understood. Using our recently developed simulation technique, we compute the water sorption isotherms of two proteins, lysozyme and Trp-cage, a miniprotein. We explicitly compare protein-water interactions in adsorption and desorption processes, by analyzing local hydration in terms of hydrogen bonding, water density, and solvent-accessible surface area. We find that significant differences in hydration behavior between adsorption and desorption manifest themselves at the individual amino acid level, in particular around polar or charged residues. We confirm this observation by demonstrating that Trp-cage’s hysteresis can be significantly reduced by mutating charged residues to alanine, a neutral and nonpolar amino acid.
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U2 - 10.1021/acs.jpclett.7b00184
DO - 10.1021/acs.jpclett.7b00184
M3 - Article
C2 - 28234480
AN - SCOPUS:85015240023
SN - 1948-7185
VL - 8
SP - 1185
EP - 1190
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
IS - 6
ER -