Purine biosynthesis pathway enzymes

Purine biosynthesis pathway enzymes are a group of catalytic proteins responsible for the production of purine nucleotides, such as adenosine and guanosine, which are essential for DNA and RNA synthesis, energy metabolism (ATP/GTP), and cell signaling [1: StatPearls]. The pathway involves a complex series of reactions starting from phosphoribosyl pyrophosphate (PRPP) to form inosine monophosphate (IMP), which is then converted into AMP and GMP [2: UniProt]. Because rapidly dividing cells, including malignant cells and activated lymphocytes, rely heavily on these enzymes to maintain their nucleotide pools, the pathway is a major target for chemotherapy and immunosuppression [3: Nature Reviews Cancer]. Drugs like methotrexate and pemetrexed interfere with folate-dependent steps in the pathway, while others like mycophenolate mofetil and 6-mercaptopurine inhibit specific enzymes like IMP dehydrogenase or PRPP amidotransferase [4: PubChem]. Dysregulation of these enzymes can lead to metabolic disorders such as gout or Lesch-Nyhan syndrome, characterized by the overproduction of uric acid [5: NIH/GARD]. Therapeutic targeting of these enzymes requires careful monitoring due to the risk of systemic toxicities, particularly myelosuppression and gastrointestinal distress, resulting from the inhibition of nucleotide synthesis in healthy proliferating tissues [6: PubMed].

Other names

De novo purine biosynthesis pathwayPurine metabolic pathwayPurine nucleotide synthesis enzymesPurine metabolism enzymes

Inhibition of specific rate-limiting or folate-dependent enzymes within the purine biosynthetic pathway to deplete intracellular pools of adenosine and guanosine nucleotides, thereby inhibiting DNA and RNA synthesis and arresting cell cycle progression [3: Nature Reviews Cancer].