Oxido-reductase catalyzed reductions

Table 5 Conditions and Results for Oxido-Reductase Catalyzed Reductions with Coenzyme Regeneration the Reaction Schemes Are Shown in Figs. 4 and 13, Respectively the Enzyme Consunqition Is Given Only for the Production Enzyme... 

Working together, photosystem I and the enzyme ferredoxin NADP oxido-reductase catalyze the hght-induced reduction of NADP to NADPH. The electrons required for this process come initially from P700 in its excited state. The resulting P700 is then reduced by the mobile carrier plastocyanin (Pc), a protein in which the boimd copper ion can exist in oxidation states +2 and +1. The net reaction is... 

Oxido-reductase. An enzyme that catalyzes oxidation-reduction reactions. 

Glucose-grown cells of G. candidum SC 5469 have also catalyzed the stereoselective reduction of ethyl-, isopropyl-, and tertiary-butyl esters of 4-chloro-3-oxobutanoic acid and methyl and ethyl esters of 4-bromo-3-oxobutanoic acid. A reaction yield of >85% and e.e. of >94% were obtained. NAD+-depen-dent oxido-reductase responsible for the stereoselective reduction of P-keto esters of 4-chloro- and 4-bromo-3-oxobutanoic acid was purified 100-fold. The molecular weight of purified enzyme is 950,000. The purified oxido-reductase was immobilized on Eupergit C and used to catalyze the reduction of (39) to S-( - )-(40). The cofactor NAD+ required for the reduction reaction was regenerated by glucose dehydrogenase. 

Superoxide dismutases are a class of oxido-reductase enzymes which contain either Cu, Fe, or Mn at the active site and catalyze the dismutation of superoxide (1), the one-electron reduction product of molecular oxygen (Eqs. 1 and 2, where M" is the metalloenzyme in the reduced state and M" is the enzyme in the oxidized state) to oxygen and hydrogen peroxide. The SOD enzymes have been shown to have efficacy in animal models of disease states proposed to be, in part, mediated by superoxide, such as myocardial ischemia-reperfusion injury, " inflammation, and cerebral ischemia-reperfusion injury. Evidence for superoxide as a mediator... 

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