Site-specific hydration dynamics of globular proteins and the role of constrained water in solvent exchange with amphiphilic cosolvents.

ABSTRACT: The thermodynamic driving forces for protein folding, association, and function are often determined by protein-water interactions. With a novel covalently bound labeling approach, we have used sensitive vibrational probes, site-selectively conjugated to two lysozyme variants-in conjunction with ultrafast two-dimensional infrared (2D-IR) spectroscopy-to investigate directly the protein-water interface. By probing alternatively a topologically flat, rigid domain and a flexible domain, we find direct experimental evidence for spatially heterogeneous hydration dynamics. The hydration environment around globular proteins can vary from exhibiting bulk-like hydration dynamics to dynamically constrained water, which results from stifled hydrogen bond switching dynamics near extended hydrophobic s

SUBMITTER: King JT 

PROVIDER: S-EPMC3422398 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature