EC Number   |
Reaction |
Reference |
|---|
   1.5.1.39 | FMNH2 + NAD(P)+ = FMN + NAD(P)H + H+ |
- |
- |
| 1.5.1.39 | FMNH2 + NAD(P)+ = FMN + NAD(P)H + H+ |
sequential reaction mechanism |
-, 716204 |
| 1.5.1.39 | FMNH2 + NAD(P)+ = FMN + NAD(P)H + H+ |
the enzyme FOR can catalyze the oxidation of NADH to NAD+ with the flavin mononucleotide (FMN) functions as the prosthetic group. In the first step, a semiquinone intermediate (FMNH) is formed by the transfer of the hydride from the nicotinamide group of NADH to the N5 in the isoalloxazine moiety of the oxidized FMN. Then, a proton transfer to the N atom near the ribitol moiety of FMNH which may result in the formation of FMNH2. Eventually, the reduced FMNH2 is oxidized to FMN by O2 molecules |
-, 764601 |
| 1.5.1.39 | FMNH2 + NAD(P)+ = FMN + NAD(P)H + H+ |
two substrate kinetic analysis by double-reciprocal plots yields a series of intersecting lines. This rules out a ping-pong bi-bi mechanism and suggests a sequential mechanism in which both FMN and NADH bind to the enzyme prior to dissociation of either product. FMN binds first, followed by NADH, kinetic mechanism, overview. The affinity of flavin toward the protein decreases only slightly upon reduction. Reduced FMN formed tends to remain bound to the enzyme where it can be re-oxidized by oxygen or, less efficiently, by various artificial electron acceptors. The enzyme-FMN complex is a functional oxidase that conducts the reduction of oxygen by NADH. Hydrogen peroxide is identified as the main product. Hydride transfer occurs from the pro-S C4 position of the nicotinamide ring and partially limits the overall turnover rate |
-, 765399 |
