De novo purine biosynthesis enzyme (None established for the overall group; common abbreviations for individual enzymes (e.g., PPAT, GART, PFAS, PAICS, ADSL, ATIC).)

De novo purine biosynthesis enzymes are a set of six key enzymes in human cells that catalyze the sequential assembly of the purine nucleotide ring from phosphoribosyl pyrophosphate (PRPP) to inosine monophosphate (IMP), which is the precursor to adenine and guanine nucleotides. These enzymes, which include amidophosphoribosyltransferase (PPAT), GAR synthetase, GAR transformylase, FGAM synthetase, AIR synthetase, SAICAR synthetase, and ATIC, work in a tightly regulated manner, forming dynamic multienzyme assemblies ("purinosomes") under high demand. The pathway sustains nucleotide pools for DNA, RNA synthesis, and cellular energy transfer, and its enzymes are targets for anti-cancer, immunosuppressive, and antibacterial therapies. Inhibition or dysregulation of this pathway impacts cell proliferation and survival, making it a central node in medicine and pharmacology[1][2][3][4][5][6].

Other names

De novo purine biosynthetic pathway enzymesPurinosome components (when describing their supramolecular assembly)DNPNB enzymes (acronym for the pathway)

Enzyme inhibition (allosteric and competitive inhibitors) Feedback inhibition by nucleotide end products (IMP, GMP, AMP) Antimetabolite action (structural analogues disrupt nucleotide assembly, e.g., 6-mercaptopurine)