. bi o - ph ] 2 4 Ja n 20 07 What is special about water as a matrix of life ?

Water offers a large temperature domain of stable liquid, and the characteristic hydrophobic effects are first a consequence of the temperature insensitivity of equation-of-state features of the aqueous medium, compared to other liquids. On this basis, the known aqueous media and conditions offer low risk compared to alternatives as a matrix to which familiar molecular biological structures and processes have adapted. The current molecular-scale understanding of hydrophobic hydration is not conformant in detail with a standard structural entropy rationalization. That classic pictorial explanation may serve as a mnemonic, but isn't necessary. A more defensible view is that peculiar hydrophobic effects can be comprehended by examination of engineering parameters characterizing liquid water. 1 Heuristic identification of solvent systems alternative to water as a matrix of life The title of this discussion is a question that hints at a practical interest in identifying alternative media for biomolecular processes and structures. In