Enzymes in Non-Aqueous Systems
Enzymes active in non-aqueous systems have been also designated as “dry enzymes”1. The notion does not imply the absence of any water at all in the reaction medium, however, since enzymatic activity requires at least 0.2 g of water per gram of protein. This amount of water, determined in sequential rehydrat,on experiments on solid vitrified samples of lysozyme by Careri et al2, is tightly bound to the surface of the protein and can be considered to be a different solvent from bulk water. Indeed its physicochemical properties are comparable to “biological water”3 also present at membrane interfaces and which plays a key role in the control of many important biological processes.
KeywordsReverse Micelle Micellar Solution Rotational Diffusion Polar Head Group Rotational Correlation Time
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