Protein hydration and its freezing phenomena: Toward the application for cell freezing and frozen food storage.

Abstract

Needless to say, water is an indispensable solvent for living things. ~60 % of our body is composed of water, the lack of which causes lots of fatal problems. It has also been known that protein function is performed only when it accompanies water molecules around the surface, i.e. hydration water molecules [1]. Therefore, it is essential to understand how water and biological component interact with each other in the view point of structure and dynamics. Freezing is a fundamental and simple phenomenon of water, and thus can be used as a “probe” for the purpose. Furthermore, preservation of cells and proteins under low temperature is crucial for numerous applications, which in turn triggers a myriad of undesirable consequences because of the freezing [2]. For these issues, we have a symposium at the 59th Annual Meeting of the Biophysical Society of Japan held in November 2021 inviting four speakers. At the symposium, the speakers review recent progresses on the understanding of the freezing phenomenon of water around cells (by Nakanishi), proteins (by Yamamoto), and model compound (by Nakagawa), which is linked to scrutinizing mode of action of biomaterials working for protecting biological specimens against freezing (by Rajan).