ENZYME-POLYELECTROLYTE NONCOVALENT COMPLEXES AS CATALYSTS FOR REACTIONS IN BINARY-MIXTURES OF POLAR ORGANIC-SOLVENTS WITH WATER

The formation of non-covalent complexes with polyelectrolytes has been suggested to enhance the resistance of enzymes towards inactivation b y organic solvents in their homogeneous mixtures with water. Existence of such complexes in water-cosolvent media was proved by experiments with a fluorescence dye, eosin. In the case of catalysis by alpha-chym otrypsin, formation of the complex with polyelectrolytes produced two major effects: i) considerable increase in enzyme activity at concentr ations of ethanol and N,N-dimethylformamide of 10-30 % v/v; ii) conser vation of the enzymatic activity at cosolvent concentrations ofmore th an 40% v/v, where the native enzyme is completely inactive. General ch aracter of the observed activation and stabilization phenomena was sho wn by example of several experimental systems.