The purine ring is built up one or a few atoms at a time on ribose 5-P H HH 5-Phosphoribosyl HC C-H Formyldycinamide OH OH I-pyrophosphate(PRPP) O=C ribonucleotide(FGAR) glutamine NH Glutamate Glutamin ①OCH2O Glutamate NI 5.Phospho-B- ATP D-ribosylamine →ADP+P OH OH Glvcine H C-HFormylglycinamidine ATP HN=C ribonucleotide (FGAM) N ADP+ P R Steps 1, 3, and 5 are analyzed b NH3 ed by one HC Glycinamide ADP+P multifunctional protein O=C ribonucleotide(GAR) Ho in some eukaryotic cells R HC CH 5-Aminoimidazole N° FormvI H4 folate ribonucleotide (AIR) H2N H4 folate
The purine ring is built up one or a few atoms at a time on ribose 5-P Steps 1, 3, and 5 are catalyzed by one multifunctional protein in some eukaryotic cells
AIR HCO H2N C ATP CH 5-Aminoimidazole-4-carboxamide →ADP+P ribonucleotide (AICAR) HON No. carboxvaminoimidazol R 0=C ribonucleotide Vo. CAIR) N° Formyl H4 folate O H4 folat H。N CH 5-Amino- 4-carboxyamino CH N-Formylaminoimidazole- imidazole ribonucleotide 2N CN 4-carboxamide ribonucleotide (FAICAR) Steps 7 and 8 are R Steps 10 and 11 are AT catalyzed by one OD H0 catalyzed by one protein ADP+P. protein in some COO in some eukaryotic cells eukaryotic cells C HN CH CH N.Succinylo-5-aminoimidazole-4 COo arboxamide ribonucleotide (SAICAR) N IN IMP is first Fumarate P- KH H formed and is then converte H2N CH 5-Aminoimidazole-4-carboxamide OH OH ribonucleotide (AICAR) H NT Inosinate(IMP) to AMP and R No° FormvI H4 folate GMP H4 folate
IMP is first formed and is then converted to AMP and GMP. Steps 7 and 8 are catalyzed by one protein in some eukaryotic cells Steps 10 and 11 are catalyzed by one protein in some eukaryotic cells