The kinetic mechanism of glutathione peroxidase from human platelets.
Human platelet glutathione peroxidase (GSH-Px) exhibits a ping-pong type kinetic mechanism. Peroxide changes the redox state of the enzyme and renders it highly stable against attack by alkylating agents. Peroxide seems also to act as a positive homotropic modulator modifying the allosteric kinetics of the enzyme. The combination of these two mechanisms accelerates response against peroxides. This finding reassesses importance of GSH-Px for the platelet protection.
D000328:Adult; D001792:Blood Platelets / Q000201:enzymology*; D005978:Glutathione / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000097:blood* / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D010084:Oxidation-Reduction; D010544:Peroxidases / Q000097:blood*; D010545:Peroxides / Q000378:metabolism; D020122:tert-Butylhydroperoxide
D010545:Peroxides; D020122:tert-Butylhydroperoxide; D010544:Peroxidases; D005979:Glutathione Peroxidase; D005978:Glutathione