Glutathione reductase of calf trabecular meshwork.

摘要: Hydrogen peroxide has been found in both calf and human aqueous humor at a level of 25 microM. It is likely, therefore, that trabecular meshwork possesses mechanisms for detoxifying H2O2, to protect itself other more distal structures the outflow pathway from oxidative damage. We have recently demonstrated an active glutathione peroxidase meshwork. In this study, we characterized complementary enzyme, reductase. The activity was present 0.120 units/min/g wet tissue (0.005 units/min/mg soluble protein). enzyme quickly lost crude extracts but could be stabilized by heating 60 degrees C 30 min. Denatured protein removed centrifuging 43,000 X g. Heating 80 10 min destroyed all activity. Addition 1 mM GSSG protected completely heat denaturation; NADP+ GSH offered some protection NADPH provided none. supernatant treatment further purified affinity chromatography on 2',5'-ADP-agarose. Overall purification 200-fold with yield 80%. pH optimum 7.0. KmS were 19 microM 78 microM, respectively. inactivation properties identical those extract. An stain disc gel electrophoresis showed exists only one form.