The paper introduces a model of human purine metabolism in situ. Chosen from among several alternative system descriptions, the model is formulated as a Generalized Mass Action system within Biochemical Systems Theory and validated with analyses of steady-state and dynamic characteristics. Eigenvalue and sensitivity analyses indicate that the model has a stable and robust steady-state. The mode...

Because de novo purine synthesis (DNPS) is a target of widely used antileukemic agents (eg, methotrexate, mercaptopurine), we determined the rate of DNPS and the expression of genes involved in purine metabolism in different subtypes of acute lymphoblastic leukemia (ALL). Among 113 children with newly diagnosed ALL, lymphoblasts with the TEL-AML1 translocation had significantly lower DNPS than ...

Studies of human purine metabolism began some 200 years ago with Scheele's identification of uric acid as a constituent of a renal calculus' and Wollaston's demonstration of urate in a tophus from his own ear.2 Just as these were among the earliest experiments in the new science of biochemistry, so Garrod's (1854)3 thread test must rank as the first assay in what we now call the discipline of c...

Deamination of nucleobases in DNA and RNA results in the formation of xanthine (X), hypoxanthine (I), oxanine, and uracil, all of which are miscoding and mutagenic in DNA and can interfere with RNA editing and function. Among many forms of nucleic acid damage, deamination arises from several unrelated mechanisms, including hydrolysis, nitrosative chemistry, and deaminase enzymes. Here we presen...

About 20 % of ruminal microbial N in dairy cows derives from purines and pyrimidines; however, their intermediary metabolism and contribution to the overall N metabolism has sparsely been described. In the present study, the postprandial patterns of net portal-drained viscera (PDV) and hepatic metabolism were assessed to evaluate purine and pyrimidine N in dairy cows. Blood was sampled simultan...