ENZYMES IN LOW WATER-SYSTEMS

Water is fundamental for enzyme action and for formation of the three- dimensional structure of proteins. Hence, it may be assumed that studi es on the interplay between water and enzymes can yield insight into e nzyme function and formation. This has proven correct, because the num erous studies that have been made on the behavior of water-soluble and membrane enzymes in systems with a low water content (reverse micelle s or enzymes suspended in nonpolar organic solvents) have revealed pro perties of enzymes that are not easily appreciated in aqueous solution s. In the low water systems, it has been possible to probe the relatio n between solvent and enzyme kinetics, as Well as some of the factors that affect enzyme thermostability and catalysis. Furthermore, the stu dies show that low water environments can be used to stabilize conform ers that exhibit unsuspected catalytic properties, as well as intermed iates of enzyme function and formation that in aqueous media have rela tively short life-times. The structure of enzymes in these unnatural c onditions is actively being explored.