Navigation:        Site Map   |    Copyright   |    Contact us   |    Acknowledgements   |   
Glutamate dehydrogenase structure
Google
 

Nicotinamide adenine dinucleotide phosphate (NADP+/NADPH)

Nicotinamide adenine dinucleotide phosphate (NADP+) definition

Nicotinamide adenine dinucleotide phosphate or NADP+ is the cofactor for some dehydrogenases. NADP+ is the oxidised form of NADPH and vice versa, NADPH id the reduced form of NADP+.

Nicotinamide adenine dinucleotide phosphate (NADP+) basic

  • Molecular formula: C21H29N7O17P3
  • Molecular weight: 744.413 Da
  • IUPAC name 1: 2'-O-phosphonoadenosine 5'-{3-[1-(3-carbamoylpyridinio)-1,4-anhydro-D-ribitol-5-yl] dihydrogen diphosphate}
  • IUPAC name 2: [(2R,3R,4S,5S)-2-(6-aminopurin-9-yl)-5-[[[[(2S,3S,4R,5R)-5-(5-carbamoylpyridin-1-yl)-3,4-dihydroxy-oxolan-2-yl]methoxy-oxido-phosphoryl]oxy-hydroxy-phosphoryl]oxymethyl]-4-hydroxy-oxolan-3-yl]oxyphosphonic acid
  • Appearance: White crystalline solid

Nicotinamide adenine dinucleotide phosphate (NADP+) structure

Nicotinamide adenine dinucleotide phosphate Nicotinamide adenine dinucleotide phosphate stick model Nicotinamide adenine dinucleotide phosphate space filling model Nicotinamide adenine dinucleotide phosphate VDW model Nicotinamide adenine dinucleotide phosphate solvent accesible surface

Different representation of the Nicotinamide adenine dinucleotide phosphate (NADP+) structure. All structures were derived from the NADP+ coordinates from the structure of Human Type I 17Beta-Hydroxysteroid Dehydrogenase complex with NADP and Estradiol (1A27.pdb). Click preview to see full resolution stereo picture.

Nicotinamide adenine dinucleotide phosphate (NADP+) synthesis pathway

In living organisms Nicotinamide adenine dinucleotide phosphate (NADP+) synthesised by one step from Nicotinamide adenine dinucleotide (NAD+). This reaction is catalyzed by NAD+ kinase EC 2.7.1.23 (systematic name - ATP:NAD+ 2'-phosphotransferase) with subsequent conversion of ATP to ADP.
L-Tryptophan to N-Formyl-L-kynurenine by tryptophan 2,3-dioxygenase, EC 1.13.11.11 NAD+ + ATP -> NADP+ + ADP catalyzed by NAD+ kinase, EC 2.7.1.23 (other names DPN kinase; nicotinamide adenine dinucleotide kinase (phosphorylating); nicotinamide adenine dinucleotide kinase; NADK)
Download ISIS Draw source file here

NADP+ and NADPH

The overall involvement of Nicotinamide adenine dinucleotide phosphate into the living cell processes is illustrated on Nicotinamide nucleotides in catabolism and biosynthesis scheme.

NADPH biosynthesis from NADP+

The major way of NADPH biosynthesis from NADP+ is the Pentose phosphate pathway (PPP). The pentose phosphate pathway is anaerobic generation of 5-carbon sugars from 6-carbon glucose. The main functions of these reactions are:
  • Generation of NADPH from NADP+
  • Generation of ribode-5-phosphate, used in nucleic acids and nucleotide biosynthesis
The pentose phosphate pathway consists from two main stages: oxidative and non-oxidative. NADP+ reduction to NADPH is take place only during oxidative stage of the pentose phosphate pathway.
D-glucose 6-phosphate + NADP+ = D-glucono-1,5-lactone 6-phosphate + NADPH + H+ by EC 1.1.1.49 Glucose 6-phosphate + NADP+ -> 6-phosphoglucono-D-lactone + NADPH + H+ catalysed by glucose 6-phosphate dehydrogenase, EC 1.1.1.49 (other names Zwischenferment; NADP-glucose-6-phosphate dehydrogenase; D-glucose 6-phosphate dehydrogenase; Entner-Doudoroff enzyme; NADP-dependent glucose 6-phosphate dehydrogenase; glucose-6-phosphate 1-dehydrogenase; G6PDH; glucose 6-phosphate dehydrogenase (NADP); GPD; 6-phosphoglucose dehydrogenase).
Systematic name: D-glucose-6-phosphate:NADP+ 1-oxidoreductase
Download ISIS Draw source file here
6-phospho-D-glucono-1,5-lactone + H2O = 6-phospho-D-gluconate + H+ by EC 3.1.1.31 6-phospho-D-glucono-1,5-lactone + H2O -> 6-phospho-D-gluconate + H+ catalysed by 6-phosphogluconolactonase, EC 3.1.1.31 (other names: 6-PGL; phosphogluconolactonase).
Systematic name: 6-phospho-D-glucono-1,5-lactone lactonohydrolase
Download ISIS Draw source file here
6-phospho-D-gluconate + NADP+ = D-ribulose 5-phosphate + CO2 + NADPH by EC 1.1.1.44 6-phospho-D-gluconate + NADP+ -> D-ribulose 5-phosphate + CO2 + NADPH catalysed by phosphogluconate dehydrogenase (decarboxylating), EC 1.1.1.41 (other names: 6-phospho-D-gluconate dehydrogenase; 6-phosphogluconate dehydrogenase (decarboxylating); 6-phosphogluconic dehydrogenase; phosphogluconic acid dehydrogenase; 6-phosphogluconic carboxylase).
Systematic name: 6-phospho-D-gluconate:NADP+ 2-oxidoreductase (decarboxylating)
Download ISIS Draw source file here

The next step - conversion of Ribulose-5-phosphate to Ribose-5-phosphate by ribose-5-phosphate isomerase (D-ribose-5-phosphate aldose-ketose-isomerase, EC 5.3.1.6) or conversion of Ribulose-5-phosphate to Xylose-5-phosphate by ribulose-phosphate 3-epimerase (D-ribulose-5-phosphate 3-epimerase, EC 5.1.3.1) is belonging to the non-oxidative stage of Pentose phosphate pathway and will not be discussed here.

NADP+ biosynthesis from NADPH

NADPH is oxidized to NADP+ in many reaction in the living cells.
  • In process of photosynthesis in the Calvin cycle of carbon fixation. The overall reaction for this cycle is:
    • 6xNADPH => 6xNADP+ - NADPH oxidation
    • 9xATP => 9xADP - energy reduction
    • 3xCO2 + 5xH2O => C3H5O3PO32- + 2xH+ + 8xPi - carbon fixation
  • Fatty acid synthesis:
    • >C=O => >COOH catalyzed by (3R)-3-hydroxyacyl-[acyl-carrier-protein]:NADP+ oxidoreductase, EC 1.1.1.100 (Other names: 3-oxoacyl-[acyl-carrier-protein] reductase; NADPH-specific 3-oxoacyl-[acylcarrier protein]reductase; 3-oxoacyl-[ACP]reductase; 3-ketoacyl acyl carrier protein reductase; β-ketoacyl-acyl carrier protein reductase; β-ketoacyl thioester reductase; β-ketoacyl-ACP reductase;β-ketoacyl-[acyl-carrier protein](ACP) reductase;β-ketoacyl reductase;β-ketoacyl acyl carrier protein (ACP) reductase)
    • -C=C- => -C-C- catalyzed by acyl-[acyl-carrier-protein]:NAD+ oxidoreductase, EC 1.3.1.9 (other names: enoyl-[acyl-carrier-protein] reductase (NADH2; enoyl-[acyl-carrier-protein] reductase (NADH); enoyl-[acyl carrier protein] reductase; NADH-specific enoyl-ACP reductase; NADH-enoyl acyl carrier protein reductase; enoyl-ACP reductase;)
  • Cholesterol biosynthesis (mevalonate pathway):
    • -CO-S-CoA => -COH catalyzed by (R)-mevalonate:NADP+ oxidoreductase (CoA-acylating), EC 1.1.1.34 (other names: hydroxymethylglutaryl-CoA reductase (NADPH); hydroxymethylglutaryl-CoA reductase (NADPH2; 3-hydroxy-3-methylglutaryl CoA reductase (NADPH); HMGCoA reductase-mevalonate:NADP-oxidoreductase (acetylating-CoA); NADPH-hydroxymethylglutaryl-CoA reductase; S-3-hydroxy-3-methylglutaryl-CoA reductase; hydroxymethylglutaryl CoA reductase (NADPH); 3-hydroxy-3-methylglutaryl-CoA reductase; β-hydroxy-β-methylglutaryl coenzyme A reductase; hydroxymethylglutaryl coenzyme A reductase (reduced nicotinamide adenine dinucleotide phosphate); HMG-CoA reductase; HMGR)

dehydrogenase.co.uk: Copyright 2007 by dehydrogenase.co.uk