Purified PGH synthase when acting on arachidonic acid in the presence of reduced nicotinamide-adenine dinucleotide or reduced nicotinamide-adenine dinucleotide 3'-phosphate generated superoxide in burst-like fashion. In eight experiments using different batches of enzyme, the mean +/- SE rate of superoxide generation from 100 U of enzyme measured as the superoxide dismutase-inhibitable reductio...

Chelation reactions of the antimitotic drug, 6-amino-purine (adenine; abbr. ADN) with the metal ions: Be ( I I ) , AI ( I II ) , Cr ( I I I ) , M n ( I I ) , Fe ( I I I ) , Co (II ) , N i ( I I ) , C u ( I I ) , P b ( I I ) , and U 0 2 ( I I ) have been investigated in aqueous solution at 3 0 ° using B j e r r u m C a l v i n pH titration technique. The formation constants have been determined ...

1. We have compared urinary purine excretion by two different methods in three separate paediatric disorders of purine metabolism: purine nucleo­ side phosphoryiase deficiency, adenosine deaminase deficiency and adenine phosphoribosyltransferase deficiency. 2. The abnormal purines identified in each case were specific for the defect and directly related to it: adenine in adenine phophoribosyltr...

The purpose of the present study was to determine if repetitive myocardial ischemia would result in the cumulative loss of mitochondrial adenine nucleotides. Isolated perfused rat hearts were subjected to continuous or intermittent ischemia. A single 5-minute period of continuous ischemia did not result in a significant decrease in the mitochondrial adenine nucleotide pool; a single 10-minute p...

6-Methylmercaptopurine ribonucleoside-5'-phosphate (MeSPuRMP), the sole metabolite of 6-methylmercaptopurine ribonucleoside (MeSPuRib), is a strong inhibitor of purine de novo synthesis, inducing depletion of intracellular purine nucleotides and subsequent cell death in several tumor cell lines. In this study prevention of MeSPuRib cytotoxicity by compounds of the purine salvage pathway was stu...

Electron spin resonance measurements were performed for the reactions of some endogenous photosensitizers (flavin mononucleotide or flavin adenine dinucleotide or folic acid or β-nicotinamide adenine dinucleotide or β-nicotinamide adenine dinucleotide phosphate or pyridoxal-5'-phosphate or urocanic acid) with oleic acid under the ultraviolet light A irradiation using α-(4-pyridyl-1-oxide)-N-ter...

The mom gene of bacteriophage Mu encodes an enzyme that converts adenine to N(6)-(1-acetamido)-adenine in the phage DNA and thereby protects the viral genome from cleavage by a wide variety of restriction endonucleases. Mu-like prophage sequences present in Haemophilus influenzae Rd (FluMu), Neisseria meningitidis type A strain Z2491 (Pnme1) and H. influenzae biotype aegyptius ATCC 11116 do not...

The isolation of a dinucleotide consisting of adenine and an unknown compound from rabbit muscle was reported in 1958 (1). Myonic acid is now proposed as a name for the latter. This name implies only that the unknown compound was first isolated from muscle. In the present communication, details of the method of isolation and of studies pertaining to the structures of myonic acid and the dinucle...