The yeast YLR209c (PNP1) gene encodes a protein highly similar to purine nucleoside phosphorylases. This protein specifically metabolized inosine and guanosine. Disruption of PNP1 led to inosine and guanosine excretion in the medium, thus showing that PNP1 plays an important role in the metabolism of these purine nucleosides in vivo.

Synthesis of several pryrazolo[4,3-e][1,2,4]-triazines is described. The absorption spectrum of some 5-substituted derivatives was found to extend to the visible region. These compounds were found to inhibit some enzymes of purine metabolism, like xanthine oxidase or bacterial purine-nucleoside phosphorylase with Ki values in the 10(-3) -10(-5) M range.

Cardiorespiratory and biochemical indicators typically used by contemporary elite athletes seem to have limited applicability. According to some recent studies, purine metabolism better reflects exercise response and muscle adaptation in this group. We propose using purine derivatives, especially plasma hypoxanthine concentration, as indicators of training status in consecutive training phases ...

Animal agricultural production systems are major sources of nonpoint pollution affecting quality of water sources. Nitrogen has been identified as the foremost source of nonpoint water pollution  and the potential negative impacts of N have become an area of public concern. protein degradation from feed ingredients is an important factorinfluencing AA supply to the duodenum. Ruminal proteolysis...

Animal agricultural production systems are major sources of nonpoint pollution affecting quality of water sources. Nitrogen has been identified as the foremost source of nonpoint water pollution  and the potential negative impacts of N have become an area of public concern. protein degradation from feed ingredients is an important factorinfluencing AA supply to the duodenum. Ruminal proteolysis...

Complex metabolism is thought to occur exclusively in the crowded intracellular environment. Here we report that diluted enzymes from lysed human leukocytes produce extracellular energy. Our findings involve two pathways: the purine nucleotide catabolic pathway and the pentose phosphate pathway, which function together to generate energy as NADPH. Glucose6P fuel for NADPH production is generate...

Suspensions enriched in isolated rabbit proximal tubules were subjected to varying degrees of oxygen deprivation-induced injury by incubating them under hypoxic conditions at pH 7.4 or pH 6.6 or under high density pelleted conditions and adenine nucleotide degradation was characterized. The major metabolite was hypoxanthine. Its levels increased with the extent of irreversible injury. It was no...

1. We have studied purine metabolism in renal failure using high-pressure liquid chromatography to determine metabolite concentrations in erythrocytes and plasma, and microradiochemical assays of enzyme activity in erythrocytes. 2. The mean activities of some of the enzymes involved in purine metabolism were raised in renal failure. Significant elevations of adenylate kinase (EC 2.7.4.3), purin...

Purine metabolism is known factor for nuclear maturation of oocytes through both follicle cells and oocyte itself. However, it is largely unknown the roles of purine metabolism in the oocyte competence for fertilization and early development. In this study, the effects of adenosine in oocyte competence for development were examined using adenosine and its synthetic inhibitors. Adenosine treatme...