[Effect of reduction of the interchain disulfide bridge of human thrombin on its enzymatic activity and structure].

It was shown that selective hydrolysis of the disulfide bridge between the A- and B-chains of human thrombin in the absence of denaturating agents decrease its proteolytic (e.g., fibrinogen-binding), esterase and amidase activities. Both chains remain bound by non-covalent interactions. A preparation of partially reduced thrombin was obtained and its kinetic parameters were determined. The experimental results suggest that the S-S bond connecting the A- and B-chains of thrombin is involved in the stabilization of the enzyme active center.