Enzymatic mechanochemistry: a new approach to studying the mechanism of enzyme action

1. Covalent binding of model enzymes, chymotrypsin and trypsin, to elastic polymer supports, nylon and viscose (cellulose) fibers, human hair, methacrylate rubber, has been effectuated. On mechanical stretching of the fibers, the catalytic activity of the enzymes bound to them decreases, and when they relax, it increases to the initial level. The data obtained by us fit the concept that the effect is due to reversible deformation of the bound enzyme molecules induced by fiber stretching. 2. Analysis of the dependence of the catalytic activity of the enzymes chemically bound to the fiber on the degree of fiber deformation shows that the reversible inactivation of the enzymes induced by support stretching occurs even if the deformation of the enzymes' molecules is as small as 0.5 A. 3. The deformation of the enzyme molecules induced by fiber stretching entails a change in the substrate specificity of the biocatalysts, i.e. the activity towards "good" substrates decreases, and towards "poor" substrates increases. 4. The deformation of the enzyme molecules induced by fiber stretching results in a decrease of the specific catalytic activity of the biocatalyst, whereas its thermal stability increases. 5. The results obtained allowed a new, mechanochemical, approach to be suggested for studying major problems of enzymatic catalysis.