Do hydration dynamics follow the structural perturbation during thermal denaturation of a protein: a terahertz absorption study.

ABSTRACT: We investigate the thermal denaturation of human serum albumin and the associated solvation using terahertz (THz) spectroscopy in aqueous buffer solution. Far- and near-ultraviolet circular dichroism spectroscopy reveal that the protein undergoes a native (N) to extended (E) state transition at temperature ≤55°C with a marginal change in the secondary and tertiary structure. At 70°C, the protein transforms into an unfolded (U) state with significant irreversible disruption of its structures. We measure the concentration- and temperature-dependent THz absorption coefficient (α) of the protein solution using a p-Ge THz difference spectrometer (2.1-2.8 THz frequency range), thereby probing the collective protein-water network dynamics. When the solvated protein is heated up to 55°C and cooled

SUBMITTER: Luong TQ 

PROVIDER: S-EPMC3175072 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature