Harmonic Behavior of Trehalose-Coated Carbon-Monoxy-Myoglobin at High Temperature

Abstract

Embedding biostructures in saccharide glasses protects them against extreme dehydration and/or exposure to very high temperature. Among the saccharides, trehalose appears to be the most effective bioprotectant. In this paper we report on the low-frequency dynamics of carbon monoxy myoglobin in an extremely dry trehalose glass measured by neutron spectroscopy. Under these conditions, the mean square displacements and the density of state function are those of a harmonic solid, up to room temperature, in contrast to D2O-hydrated myoglobin, in which a dynamical transition to a nonharmonic regime has been observed at approximately 180 K (Doster et al., 1989. Nature. 337:754-756). The protective effect of trehalose is correlated, therefore, with a trapping of the protein in a harmonic potential, even at relatively high temperature.

Self-assembly of trehalose molecules on a lysozyme surface: the broken glass hypothesis

“…Infrared spectroscopy experiments 21 show that there is a large number of direct hydrogen bonds formed between trehalose and lysozyme, which is suggestive of the water replacement hypothesis. However, there is also much experimental [8][9][10][11] and theoretical 12,13,15,16 data showing that the protein-sugar interactions are better described in terms of water entrapment hypotheses.…”

Temperature and timescale dependence of protein dynamics in methanol : water mixtures

“…33,34 The presence of highly-viscous solvents such as trehalose has been shown to abolish the dynamical transition. 35 In the present work we investigate the dependence of the dynamical transition on solvent composition. In recent years a number of cosolvents have found a wide range of uses in biology: as cryosolvents, protein denaturants, protein fold stabilizers, protein function modulators, and more.…”

Anharmonic transitions in nearly dry l-cysteine I

“…The microscopic nature of this transition is still an object of debate. The discussed possibilities include quantum effects near a zero point vibration [7], and methyl group rotation associated with anharmonicity [2,8]. Vibrational modes play a very important role in the conformational arrangement of different functional states and also in the energetic balance of the chemical bonds [9].…”