β-Nicotinamide adenine dinucleotide phosphate

NADP is nicotinamide adenine dinucleotide phosphate, acting as a key cofactor for electron transfer in the metabolism of all organisms, being alternately oxidized (NADP+) and reduced (NADPH).
Nicotinamide adenine dinucleotide phosphate. A coenzyme composed of ribosylnicotinamide 5'-phosphate (NMN) coupled by pyrophosphate linkage to the 5'-phosphate adenosine 2',5'-bisphosphate. It serves as an electron carrier in a number of reactions, being alternately oxidized (NADP+) and reduced (NADPH). (Dorland, 27th ed)
Triphosphopyridine nucleotide is white or off-white powder, it is easy to absorb moisture and deliquescence. pKa{1}=3.9; pKa{2}=6.1. It is soluble in water, methanol, insoluble in ethanol, insoluble in ether and ethyl acetate.
The oxidized form of nicotinamide adenine dinucleotide phosphate (NADP) that receives electrons from photosystem I during photosynthesis. It exists as an anion under normal physiologic conditions.
Purify NMN by passage through a column of Dowex-1 (Clform) and washing with H2O until no absorbance is observed at 260 nm. The tubes containing NMN are pooled, adjusted to pH 5.5-6 and evaporated in vacuo to a small volume. This is adjusted to pH 3 with dilute HNO3 in an ice-bath and treated with 20volumes of Me2CO at 0-5o. The heavy white precipitate is collected by centrifugation at 0o. It is best stored wet and frozen or it can be dried to give a gummy residue. It has max 266nm ( 4,600) and min 249nm ( 3600) at pH 7.0 (i.e. no absorption at 340nm). It can be estimated by reaction with CNor hydrosulfite which form the 4-adducts (equivalent to NADH) which have UV max 340nm ( 6,200). Thus after reaction, an OD340 of one is obtained from a 0.1612mM solution in a 1cm path cuvette. [Plaut & Plaut Biochemical Preparations 5 56 1957, Maplan & Stolzenbach Methods Enzymol 3 899 1957, Kaplan et al. J Am Chem Soc 77 815 1955, Beilstein 22/2 V 168.]