Identifiers | |
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53-59-8 | |
3D model (Jmol) | Interactive image |
ChEBI | CHEBI:44409 |
ChEMBL | ChEMBL213053 |
ChemSpider | 5674 |
ECHA InfoCard | 100.000.163 |
MeSH | NADP |
PubChem | 5885 |
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Properties | |
C21H29N7O17P3 | |
Molar mass | 744.42 g·mol−1 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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what is ?) | (|
Infobox references | |
Nicotinamide adenine dinucleotide phosphate, abbreviated NADP+ or, in older notation, TPN (triphosphopyridine nucleotide), is a cofactor used in anabolic reactions, such as lipid and nucleic acid synthesis, which require NADPH as a reducing agent.
NADPH is the reduced form of NADP+. NADP+ differs from NAD+ in the presence of an additional phosphate group on the 2' position of the ribose ring that carries the adenine moiety.
In photosynthetic organisms, NADPH is produced by ferredoxin-NADP+ reductase in the last step of the electron chain of the light reactions of photosynthesis. It is used as reducing power for the biosynthetic reactions in the Calvin cycle to assimilate water. It is used to help turn the carbon dioxide into glucose. It is also needed in the reduction of nitrate into ammonia for plant assimilation in nitrogen cycle.
The major source of NADPH in animals and other non-photosynthetic organisms is the pentose phosphate pathway.
However, there are several other lesser-known mechanisms of generating NADPH, all of which depend on the presence of mitochondria. The key enzymes in these processes are: NADP-linked malic enzyme, NADP-linked isocitrate dehydrogenase, NADP-linked glutamate dehydrogenase and nicotinamide nucleotide transhydrogenase. The isocitrate dehydrogenase mechanism appears to be the major source of NADPH in fat and possibly also liver cells. Also, in mitochondria, NADH kinase produces NADPH and ADP, using NADH and ATP as substrates.