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Nucleotide Biosynthesis. PRPP synthesis Purines Carbamoyl phosphate synthetase II Pyrimidines Nucleoside kinases Deoxyribonucleotides. Biosynthesis of Purine Nucleotides. O. NH 2. H. N. O. N. N. N. OPO 3 CH 2. OPO 3 CH 2. O. O. N. N. HO. HO. OH. OH. 5’-UMP. 5’-AMP.
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Nucleotide Biosynthesis • PRPP synthesis • Purines • Carbamoyl phosphate synthetase II • Pyrimidines • Nucleoside kinases • Deoxyribonucleotides
Biosynthesis of Purine Nucleotides O NH2 H N O N N N OPO3CH2 OPO3CH2 O O N N HO HO OH OH 5’-UMP 5’-AMP Pyrimidine Purine
9. Add formyl-THF 2. Displace pyrophosphate with glutamine (N) 8. Get NH2 from aspartate (N) 3. Add glycine (N) 4. Add formyl-THF 6. Add glutamine (N) C N C N C C 7. Add CO2 C N N Ribose-5-PO4 Purine Synthesis 10 Steps: 1. Activate the Ribose (PRPP) 10. Close large ring 5. Close small ring
CH2OPO3= CH2OPO3= Alpha position O O OPP OH HO HO OH OH ATP + AMP PRPP Synthetase Ribose-5-P 5-Phosphoribosyl-PP (PRPP) Activate Ribose PRPP allows ribose to be joined to a base
CH2OPO3= CH2OPO3= CH2OPO3= O O O NH3 NH3 OPP HO HO HO OH OH OH COO- H3N-C-H CH2 NH2 2C H CH2 H2N C O =C R O COO- O NH H C NH3 H HO OH 5-phosphoribosylamine 5-PRPP L-glutamine Glycine
NH2 2C H NH NH O =C 2C 2C H H NH HN 2C R H C C H H O =C =C O NH C H C R R O O H2N O O NH NH R O NH HO OH HO HO OH OH HO OH Formyl-THF Glutamine Ring Closure
O O C NH O C NH C H2N C C H C H2N C H C H2N NH NH R R COO + H3N-C-H CH2 COO- CO2 ATP L-aspartate + ATP
O O O N C C NH NH H2N H2N C C C C H H HC C C H2N N O NH NH R R N C C C C H H C N O N Hypoxanthine HO OH Formyl-THF R= OPO3CH2 Ring closure R Inosine 5’-phosphate
Summary of Purine Biosynthesis Amino acids Glutamine 2 Glycine 1 Aspartate 1 Coenzymes 1 PRPP synthesis N10-formyl THF 2 1 Glutamine Energy 1 Glycine ATP 6 1 Aspartate Others 1 CO2 CO2 1 1 Small ring closure Ribose-5-PO4 1
-COO-CH2-CH-COO- O NH2 NH N N N H H C N H C N R R O N N N N N R O C C C C C C C C C C N C C C C C H N C H C C C C C H H H H H N H C C O N N R H2 N O O O O O R N N N N N HO HO HO HO HO OH OH OH OH OH Asp + GTP 5’AMP NAD+ Adenylsuccinate Glutamine 5’-XMP ATP 5’-GMP
5’-AMP ADP ATP 5’-IMP dADP dATP 5’-XMP 5’-GMP GDP GTP Summary of Purine Nucleotide Biosynthesis dGDP dGTP