Physical Insights into the Bio-preservation of Proteins by Glassy Solvents: Why is Glycerol better than Trehalose at low Temperatures?

Özet

Biopreservation has been a critical area of technical and scientific research as it enables various forms of biomolecular therapeutic agents to find practical use in medicine. The mechanism at which biomimicry-inspired solutions to stabilize biomolecules has been of great scientific interest. We have studied the behavior of lysozyme immersed in glycerol and trehalose, two solvents frequently used in the bio-preservation of proteins, with the purpose of identifying the microscopic origins of their very different dynamical suppression capabilities. In agreement with experiments, we find that glycerol is superior to trehalose at low temperatures, although the latter is deeper in the glassy state, while trehalose is better at higher temperatures. We traced the basis of this phenomenon to the different temperature dependencies of the intermolecular hydrogen bonds between the model protein structure and the surrounding solvent.