Purine nucleoside-utilizing enzymes

Purine nucleoside-utilizing enzymes are a functional class of enzymes responsible for the synthesis, salvage, and degradation of purine nucleosides and nucleotides, which are essential for DNA and RNA production, energy transfer (ATP/GTP), and cellular signaling (Miles et al., 1976; UniProt). Key members of this group include adenosine deaminase (ADA), purine nucleoside phosphorylase (PNP), xanthine oxidase (XO), and inosine monophosphate dehydrogenase (IMPDH) (Guide to Pharmacology). These enzymes are critical therapeutic targets; for example, XO inhibitors like allopurinol are used to treat gout by reducing uric acid production, while IMPDH inhibitors like mycophenolate mofetil are used as immunosuppressants (PubChem; NIH). Furthermore, many anticancer and antiviral drugs are purine analogs that serve as substrates or inhibitors for these enzymes, disrupting nucleotide pools or being incorporated into nucleic acids to induce cell death (PubMed). Because these enzymes are central to the metabolism of all proliferating cells, drugs targeting them often require careful dosing to balance efficacy against systemic toxicities such as bone marrow suppression (StatPearls). Targeting these enzymes also provides a strategy for treating parasitic infections, as many parasites rely exclusively on salvage pathways for purine acquisition (PubMed).

Other names

Purine metabolic enzymesPurine salvage pathway enzymesPurine-utilizing enzymes

Inhibition of specific enzymes within the purine metabolic pathway (e.g., ADA, PNP, XO, IMPDH) or acting as antimetabolites that are incorporated into DNA/RNA, leading to cell cycle arrest and apoptosis (PubChem; PubMed).