Several aspects of purine metabolism were studied in peripheral blood mononuclear cells and fibroblasts from a patient with purine nucleoside phosphorylase deficiency and compared to cells from normal controls. Intact cells were incubated with radioactive purine bases and all purine metabolites were extracted and analyzed. Incubation of purine nucleoside phosphorylase-deficient cells with [3H]h...

Klein (1) has made a detailed investigation of the action of “purine nucleosidase” on the various purine desoxyribosides. He found that preparations of animal tissues which split purine ribosides also split the purine desoxyribosides, yielding the purine base and a reducing sugar. The enzyme preparations were inactivated upon dialysis, but could be reactivated by the addition of arsenate or pho...

Riboswitches are regulatory RNA that control gene expression by undergoing conformational changes on ligand binding. Using phylogenetic analysis and comparative genomics we have been able to identify the class of genes/operons regulated by the purine riboswitch and obtain a high-resolution map of purine riboswitch distribution across all bacterial groups. In the process, we are able to explain ...

Leishmania are protozoan parasites that cause significant morbidity and mortality in humans, afflicting approximately 12 million people worldwide. These parasites are auxotrophic for purines and have evolved a unique set of purine transporters and salvage enzymes to scavenge these essential nutrients from their host. Hence, purine salvage components provide attractive targets for drug design. A...

A theoretical study at the B3LYP/6-31++G(d,p) level was performed on the tatumerization of 7H-purine-2, 6-diamine into 9H-purine-2, 6-diamine. Such a tautomerism can take place via three different pathways namely A, B, and C. The energetic results associated with the gas phase reveal that pathways A, B, and C display a very high activation Gibbs free energy of 45.1, 68.6 and 48.9 kcal/mol, resp...

The purine metabolism of several genera of parasitic protozoa, is of interest partly due to their sensitivity to purine analogues, and to differences in the enzymes of purine metabolism compared to mammalian systems [l-6]. Trichomonas vaginalis, the causative agent of trichomonal vaginitis, a mild, but very common, sexually-transmitted disease, has not been studied in this respect; there is a g...

how to cite this article: boroujerdi r, shariati m, naddafnia h, rezaei h. small duplication of hprt 1 gene may be causative for lesh- nyhan disease in iranian patients. iran j child neurol. 2015 winter;9(1):103-106. abstract deficiency of hypoxanthine-guanine phosphoribosyltransferase (hgprt) is a rare inborn error of purine metabolism and is characterized by uric acid overproduction along wit...

background & aim: clematis is an ornamental and medicinal plant that is primarily planted as an ornamental plant. clematis orientalis is native to asia and central europe, used as an antiseptic and refrigerant. the propagation of clematis is very important. in this study, the effects of plant growth regulators on rooting and growth of the plants in vitro culture were examined. experimental:...

The pathway for the utilization of 2,6-diaminopurine (DAP) as an exogenous purine source in Salmonella typhimurium was examined. In strains able to use DAP as a purine source, mutant derivatives lacking either purine nucleoside phosphorylase or adenosine deaminase activity lost the ability to do so. The implied pathway of DAP utilization was via its conversion to DAP ribonucleoside by purine nu...

1. Abstract 2. Introduction 3. Purine and pyrimidine metabolism during somatic embryogenesis 3.1. Maintenance of embryogenic tissue 3.1.1. Purine metabolism during maintenance of embryogenic tissue 3.1.2. Pyrimidine metabolism during maintenance of embryogenic tissue 3.2. Development of somatic embryos 3.2.1. Purine metabolism during development of somatic embryos 3.2.2. Pyrimidine metabolism d...