Szent-Győrgi called water the “matrix of life” and claimed that there was no life without it. This statement is true, as far as we know, on our planet, but it is not clear whether it must hold throughout the cosmos. To evaluate that question requires a close consideration of the many varied and subtle roles that water plays in living cells—a consideration that must be free of both an assumed essentialism that gives water an almost mystical life-giving agency and a traditional tendency to see it as a merely passive solvent. Water is a participant in the “life of the cell,” and here I describe some of the features of that active agency. Water's value for molecular biology comes from both the structural and dynamic characteristics of its status as a complex, structured liquid as well as its nature as a polar, protic, and amphoteric reagent. Any discussion of water as life’s matrix must, however, begin with an acknowledgment that our understanding of it as both a liquid and a solvent is still incomplete.
My Note: From the paper-
Low-frequency, large-amplitude modes in the terahertz range are particularly important in controlling the conformational changes that dominate protein function, and are conveniently probed using terahertz spectroscopy….However, there is no simple qualitative account of how protein and solvent dynamics interact. Fluctuations of both take place over a wide range of timescales from milliseconds to picoseconds, influencing several aspects of protein function . Because no single technique can span so many temporal orders of magnitude, there has been considerable debate about how to reconcile the results of different experimental methods that explore dynamics, such as NMR relaxation, neutron scattering, ultrafast IR, and terahertz spectroscopies
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