Solvent effects on conformational dynamics of proteins: Cytochrome c in a dried trehalose film

Abstract

Articles you may be interested inOptimizing conical intersections of solvated molecules: The combined spin-flip density functional theory/effective fragment potential method J. Chem. Phys. 137, 034116 (2012); 10.1063/1.4734314 Solvent effect on the folding dynamics and structure of E6-associated protein characterized from ab initio protein folding simulations J. Chem. Phys. 136, 135102 (2012); 10.1063/1.3698164 Communication: Free-energy analysis of hydration effect on protein with explicit solvent: Equilibrium fluctuation of cytochrome cThe spectral diffusion dynamics of free base cytochrome c ͑H2-Cc͒ in a dry trehalose film is tremendously enhanced as compared to a glycerol/water glass. We show that relaxation as well as fluctuation processes contribute to the spectral diffusion dynamics. Relaxation shows up in aging phenomena which can be measured in a separate fashion. In both solvents, the spectral diffusion as well as the aging dynamics follow power laws in time. The respective exponents are quite different, yet the influence of the solvent on them is only marginal. The large difference in the magnitude of the spectral diffusion dynamics in the two solvents can be traced back to a correspondingly large difference in the inhomogeneous width which itself seems to come from the much higher glass transition temperature in trehalose, which is close to the unfolding temperature of cytochrome c.

Spectroscopy of proteins at low temperature. Part I: Experiments with molecular ensembles

“…Hence, we can safely assume that spectral diffusion in proteins is qualitatively drastically different from glasses. The dynamics in the waiting time domain as well as in the aging time domain seem to be governed by power laws with rather uniform exponents [86,87].…”

Proteins in Saccharides Matrices and the Trehalose Peculiarity: Biochemical and Biophysical Properties

“…Results on spectral diffusion dynamics of cytochrome (cyt-c) suggests that large-scale motions are more impaired in a trehalose than in a glycerol glass [118]. Optical heme absorption and IR CO bands were also investigated in similar sugar-coated cytochrome systems.…”

Physics of Proteins at Low Temperature

“…27 The exponents for the two solvents (Gl/W and TH) are slightly different, 0.29 and 0.23, respectively. 28 Notice that there is a remarkable solvent effect in the magnitude of SD: The SD-width in TH is larger by almost a factor of 2. Data from thermal cycling SD-experiments are shown in Figs.3a and b.…”