ISOLATION AND IDENTIFICATION OF ADENOSINE TRIPHOSPHORIBOSYL NICOTINAMIDE ADENINE DINUCLEOTIDEPHOSPHATE FROM AZOTOBACTER-VINELANDII

A novel type of pyridine nucleotide, containing two adenosine triphosphate ribose residues rather than one, was isolated from Azotobacter vinelandii strain O. The nucleotide was shown to be 2''- or 3''-(2'-phosphoadenosine-5'-diphosphoribosyl)nicotinamide adenine dinucleotide phosphate, in which 2'-phospho-5'-diphosphoadenosylribose was glycosidically linked to the NADP at position 2' or 3' of the nicotinamide mononucleotide moiety. The ATPribosylNADP did not show coenzyme activity for yeast glucose 6-phosphate dehydrogenase, nor was it cleaved by Neurospora crassa NAD(P) glycohydrolase, indicating that the biological properties conferred on the beta-NADP molecule were largely modified by the attachment of the ATP-ribose group.