Folate and purine biosynthesis enzymes

Folate and purine biosynthesis enzymes are a critical group of metabolic proteins responsible for the production of nucleotides required for DNA and RNA synthesis (Source: PubMed PMC3526987). This pathway, often referred to as one-carbon metabolism, includes key enzymes such as dihydrofolate reductase (DHFR), thymidylate synthase (TYMS), and glycinamide ribonucleotide transformylase (GART) (Source: UniProt P00374, P04818, P22102). These enzymes facilitate the transfer of one-carbon units necessary for the de novo synthesis of purines and the pyrimidine thymidine (Source: StatPearls - Folate Deficiency). Because rapidly dividing cells, such as cancer cells and activated immune cells, have a high demand for nucleotides, these enzymes are major therapeutic targets in oncology and rheumatology (Source: NIH - Cancer Treatment Strategies). Drugs like methotrexate and pemetrexed act as antifolates, competitively inhibiting these enzymes to disrupt DNA synthesis and induce cell death (Source: PubChem CID 126941). Beyond human health, these enzymes are also targeted by antimicrobial agents like trimethoprim that exploit the metabolic differences between humans and pathogens (Source: Wikipedia - Trimethoprim).

Other names

Folate metabolism enzymesOne-carbon metabolism enzymesPurine de novo biosynthesis enzymesAntifolate targetsPurinosomeNucleotide biosynthesis enzymes

These drugs function by inhibiting specific enzymes within the folate and purine metabolic pathways, such as dihydrofolate reductase (DHFR), thymidylate synthase (TYMS), and glycinamide ribonucleotide transformylase (GART). This inhibition leads to the depletion of intracellular tetrahydrofolate and nucleotide pools (dTTP, dATP, dGTP), which subsequently halts DNA replication, repair, and RNA synthesis, resulting in cell cycle arrest or apoptosis (Source: StatPearls - Antimetabolites; PubMed PMC3526987).