Schizophrenia (SZ) is a biochemically complex disorder characterized by widespread defects in multiple metabolic pathways whose dynamic interactions, until recently, have been difficult to examine. Rather, evidence for these alterations has been collected piecemeal, limiting the potential to inform our understanding of the interactions amongst relevant biochemical pathways. We herein review per...

Resistance to purine analogs by loss of nucleotide-forming capacity was observed in a number of experimental tumor systems. Such resistance frequently was accom panied by loss of specific purine ribonucleotide pyrophosphorylase activities. How ever, it is evident that other mechanisms of resistance to purine analogs also exist both in mouse leukemia and in human leukemia. Attention was focused ...

The finding that the purine portions of both adenosine triphosphate and guanosine triphosphate of the mature rabbit erythrocyte are not metabolically stable constituents of that cell, as is the heme of hemoglobin, suggested the possibility of a metabolic renewal of the nucleotides during the life of the cell (1, 2). The absence of any detectable utilization of sodium formate-Cl4 or of glycine-2...

Various derivatives of adenosine were prepared by acylation of adenosine (6-amino-9-(bD-ribofuranosyl)purine (1) with different molar equivalents of acetic anhydride and/or pivaloyl chloride in pyridine. Compounds 6-acetylamino-9-[(2,3,5-tri-O-acetyl)-b-Dribofuranosyl]purine (3), 6-amino-9-[(2,3,5-tri-O-acetyl)-b-D-ribofuranosyl]purine (4), and 6-pivaloylamino-9-[(2,3,5-tri-O-pivaloyl)-b-D-ribo...

1. Abstract 2. Introduction 3. Structure and properties of purine alkaloids found in nature 4. Distribution of purine alkaloids 4.1. Coffee and related Coffea plants 4.2. Tea and related Camellia plants 4.3. Cacao and related Theobroma and Herrania plants 4.4. Other plants 5. The “core pathway” of caffeine biosynthesis: conversion of xanthosine to caffeine 5.1. Production of 7-methylxanthosine ...

Malaria, caused by Plasmodia parasites, affects hundreds of millions of people. As purine auxotrophs, Plasmodia use transporters to import host purines for subsequent metabolism by the purine salvage pathway. Thus purine transporters are attractive drug targets. All sequenced Plasmodia genomes encode four ENTs (equilibrative nucleoside transporters). During the pathogenic intraerythrocytic stag...

Purine nucleotides are essential components to sustain plant growth and development. In plants they are either synthesized "de novo" during the process of purine biosynthesis or are recycled from purine bases and purine nucleosides throughout the salvage pathway. Comparison between animals, microorganisms and Arabidopsis, the first plant species with a completely sequenced genome, shows that pl...

1. Variables that affect the measurement of purine synthesis de novo in human lymphocytes were studied and a reliable method of measurement of purine synthetic activity in these cells was established. 2. Purine synthesis de novo was measured as the rate of incorporation of [14C] formate into alpha-N-formylglycinamide ribonucleotide when further steps in the biosynthetic pathway had been blocked...

Human peripheral blood leukocytes were studied for the presence and the regulatory properties of the pathway of de novo synthesis of purine nucleotides. The cells were found to incorporate the labeled precursors formate and glycine into purines. The rate of [14C]-formate incorporation was decreased by several compounds known to inhibit purine synthesis by affecting the activity by glutamine pho...