NADP oxidoreductase

Relkin N and Nelson T. Regulation and. properties of an NADP+ oxidoreductase which functions as a. y-hydroxybutyrate dehydrogenase. J Neurochem, 1983, 40, 1639. 

Ebenau-Jehle, M Boll, G Fuchs (2003) 2-oxoglutarate NADP oxidoreductase m Azoarcus evansii properties and function in electron transfer reactions in aromatic ring reduction. J Bacterial 185 6119-6129. 

The enzyme ferridoxin (Fd) NADP + oxidoreductase accepts the electron from Fd, one at a time, as it proceeds from its oxidized form through a semiquinone intermediate to its fully reduced form. The enzyme then transfers a hydride ion to NADP converting to its reduced state NADPH. Uptake of a proton in the reduction of NADP+ further contributes to the proton gradient across the thylakoid membrane driving ATP synthesis. 

This enzyme [EC 1.5.1.24], also referred to as A -(1-l-carboxyethyl)-L-ornithine NADP+ oxidoreductase, reversibly catalyzes the reaction of ornithine with pyruvate and NADPH to produce A -(l-carboxyethyl)ornithine, NADP+, and water. Lysine can also serve as a substrate, acting on A , albeit not as effectively as ornithine. 

Onda Y, Hase T (2004) FAD assembly and thylakoid membrane binding of ferredoxin NADP oxidoreductase in chloroplasts. FEBS Lett 564 116-120... 

Inui H, Ono K, Miyatake K, Nakano Y, Kitaoka S (1987) Purification and characterization of pyruvate NADP+ oxidoreductase in Euglena gracilis. J Biol Chem 262 9130-9135... 

Rotte C, Stejskal F, Zhu G, Keithly JS, Martin W (2001) Pyruvate NADP+ oxidoreductase from the mitochondrion of Euglena gracilis and from the apicomplexan Cryptosporidium parvum a biochemical relic linking pyruvate metabolism in mitochondriate and amitochondriate protists. Mol Biol Evol 18 710-720 Schnarrenberger C, Martin W (2002) Evolution of the enzymes of the citric acid cycle and the glyoxylate cycle of higher plants. A case study of endosymbiotic gene transfer. Eur J Biochem 269 868-883... 

Fig. 4 Transmission electron microscopy of a longitudinal section of the posterior end of a Cryptosporidium parvum sporozoite showing immunogold localization of pyruvate NADP+ oxidoreductase (CpPNO). The mitochondrion-like organelle ( ) is posterior to the nucleus, and lies between the nucleus and the CB. It is labeled by mitochondrion-specific 15-nm gold anti- particles. Small -nm gold goat anti-CpPFO particles (arrows) show the localization of CpPNO. There are no 6-nm particles localized within the mitochondrion-like organelle (reprinted from Fig. 12 of Ctrnacta et al. 2006 with permission of the publishers)...

Inui H, Ono K, Miyatake K, Nakano Y, Kitaoka S (1987) Purification and characterization of pyruvate NADP+ oxidoreductase in Euglena gracilis. J Biol Chem 262 9130-9135 Johnson D, Cascio M, Sawaya M, Gingery I, Schroder E (2006) Crystal structures of a tetrahedral open pore ferritin from the hyperthermophilic archaeon. Structure 13 637-648... 

Nakazawa M, Inui H, Yamaji R, Yamamoto T, Takenaka S, Ueda M, Nakano Y, Miyatake (2000) The origin of pyruvate NADP+ oxidoreductase in mitochondria of Euglena gracilis. FEBS Lett 479 155-156... 

Fig. 1 Enzymes localized to B. hominis mitochondrial-like organelle. The enzymes are 1 malic enzyme, 2 pyruvate NADP oxidoreductase, 3 acetate succinate CoA transferase, 4 succinate thiokinase, 5 a-ketoglutarate dehydrogenase, 6 isocitrate dehydrogenase, and 7 aconitase...

Another flavoprotein that makes use of both one-and two-electron transfer reactions is ferredoxin-NADP+ oxidoreductase (Eq. 15-28). Its bound FAD accepts electrons one at a time from each of the two... 

The soluble electron carriers released from the reaction centers into the cytoplasm of bacteria or into the stroma of chloroplasts are reduced single-electron carriers. Bacterial ferredoxin with two Fe4S4 clusters is formed by bacteria if enough iron is present. In its absence flavodoxin (Chapter 15), which may carry either one or two electrons, is used. In chloroplasts the carrier is the soluble chloroplast ferredoxin (Fig. 16-16,C), which contains one Fe2S2 center. Reduced ferredoxin transfers electrons to NADP+ (Eq. 15-28) via ferredoxin NADP oxidoreductase, a flavoprotein of known three-dimensional structure.367 369... 

The Z scheme. [(Mn)4 = a complex of four Mn atoms bound to the reaction center of photosystem II Yz = tyrosine side chain Phe a = pheophytin a QA and Qb = two molecules of plastoquinone Cyt b/f= cytochrome hf,f complex PC = plastocyanin Chi a = chlorophyll a Q = phylloquinone (vitamin K,) Fe-Sx, Fe-SA, and Fe-SB = iron-sulfur centers in the reaction center of photosystem I FD = ferredoxin FP = flavoprotein (ferredoxin-NADP oxidoreductase).] The sequence of electron transfer through Fe-SA and Fe-SB is not yet clear. 

Photosystem I contains three iron-sulfur clusters firmly associated with the reaction center. These are designated Fe-Sx, Fe-SA, and Fe-SB in figure 15.17. The cysteines of Fe-Sx are provided by the two main polypeptides of the reaction center, which also bind P700 and its initial electron acceptors Fe-SA and Fe-SB are on a separate polypeptide. The quinone that is reduced in photosystem I probably transfers an electron to Fe-Sx, which in turn reduces Fe-SA and Fe-SB. From here, electrons move to ferredoxin, a soluble iron-sulfur protein found in the chloroplast stroma, then to a flavoprotein (ferredoxin-NADP oxidoreductase), and finally to NADP+. 

The reduction of />coumaroyl-CoA (3.31) to />coumaryl aldehyde (3.69) is catalyzed by the enzyme cinnamoyl-CoA NADP oxidoreductase (CCR). This enzyme was initially purified from soybean cultures (Wegenmayer et al., 1976), and was later on efficiently isolated from lignifying cambium of eucalyps (Eucalyptus gunnii) (Gofifiier et al., 1994). A CCR cDNA was identified in a cDNA library that was screened with oligonucleotiede derived from the peptide sequence of the CCR protein. CCR is considered the first enzyme committed towards the biosynthesis of monolignols and shows... 

Goffner, D., Campbell, M.M., Campargue, C., Clastre, M., Borderies, G., Boudet, A. and Boudet, A.M., 1994, Purification and characterization of cinnamoyl-CoA NADP oxidoreductase in Eucalyptus gunnii, Plant Physiol. 106 625-632. 

Figure 2. Schematic of photoinduced electron transport and phosphorylation reactions considered to occur in chloroplast lamellae [from Moreland and Hilton (2)]. Open arrows indicate light reactions solid arrows indicate dark reactions and the narrow dashed line represents the cyclic pathway. Abbreviations used PS I, photosystem I PS II, photosystem II Y, postulated electron donor for photosystem II Q, unknown primary electron acceptor for photosystem II PQ, plastoquinones cyt b, b-type cytochromes cyt f, cytochrome f PC, plastocyanin P700, reaction center chlorophyll of photosystem I FRS, ferredoxin-reducing substance Fd, ferredoxin Fp, ferredoxin-NADP oxidoreductase FeCy, ferricyanide asc, ascorbate and DPIP, 2,6-dichloropheno-lindophenol. The numbers la, lb, 2, 3, and 4 indicate postulated sites of action by...

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