Why is de novo biosynthesis of purines markedly elevated in patients with adeficiency in hypoxanthine-guanine phosphoribosyl transferase (HGPRT)?5-Fluoruracil is converted to methotrexate by a DPD deficiency, leadingto increased purine biosynthesis.HGPRT deficiency prevents purine salvage, leading to increased purinebiosynthesis to make up for it.HGPRT increases pyrimidine salvage and thereby increases purinebiosynthesis as a result.Increased purine biosynthesis is the result of ATP hydrolysis during theproduction of cyclic AMP.

HGPRT is an important enzyme in the recycling of building blocks of nucleic acids like DNA or RNA.…

Why is de novo biosynthesis of purines markedly elevated in patients with a deficiency in hypoxanthine-guanine phosphoribosyl transferase (HGPRT)? 5-Fluoruracil is converted to methotrexate by a DPD deficiency, leading to increased purine biosynthesis. OHGPRT deficiency prevents purine salvage, leading to increased purine biosynthesis to make up for it. HGPRT increases pyrimidine salvage and thereby increases purine biosynthesis as a result. Increased purine biosynthesis is the result of ATP hydrolysis during the production of cyclic AMP.

Why is de novo biosynthesis of purines markedly elevated in patients with a deficiency in hypoxanthine-guanine phosphoribosyl transferase (HGPRT)? 5-Fluoruracil is converted to methotrexate by a DPD deficiency, leading to increased purine biosynthesis. OHGPRT deficiency prevents purine salvage, leading to increased purine biosynthesis to make up for it. HGPRT increases pyrimidine salvage and thereby increases purine biosynthesis as a result. Increased purine biosynthesis is the result of ATP hydrolysis during the production of cyclic AMP.

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter26: Synthesis And Degradation Of Nucleotides

Section: Chapter Questions

Problem 14P: The Energy Cost of dTTP Synthesis (Integrates with Chapter 20.) Starting from HCO3, glutamine,...

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