THE ROLE OF WATER IN BIOLOGICAL-SYSTEMS

A general model of the liquid water structure consistent with its phys ical, chemical, structural, and also biological properties has not bee n described in the literature so far. Therefore, different structure m odels of liquid water have been taken into account in relation to its OH stretching Raman modes. Some factors (structure factor, H-bond coop erativity) typical of liquid and biological water have been considered . Also, the different roles played by water in biological systems are elucidated and discussed by means of a few general structure models, s uitable for explaining the perturbations induced on liquid water by so lutes (ionic, acids and bases, apolar) and surfaces. In particular, th e possibility of strong acid-base H-bond interactions between differen t groups has been explored together with the biological role of water. Furthermore, the modulating effect of water on the H-bond strength an d the consequent properties have been hypothesized. Finally, the behav iour of water structure in tissues and its possible correlation with n ormal and pathological conditions are reported.