PETER PAZMANY CATHOLIC UNIVERSITY Consortium members SEMMELWEIS UNIVERSITY, DIALOG CAMPUS PUBLISHER

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1 SEMMELWEIS UIVERSITY PETER PAZMAY ATLI UIVERSITY Development of omplex urricula for Molecular Bionics and Infobionics Programs within a consortial* framework** onsortium leader PETER PAZMAY ATLI UIVERSITY onsortium members SEMMELWEIS UIVERSITY, DIALG AMPUS PUBLISER The Project has been realised with the support of the European Union and has been co-financed by the European Social Fund *** **Molekuláris bionika és Infobionika Szakok tananyagának komplex fejlesztése konzorciumi keretben ***A projekt az Európai Unió támogatásával, az Európai Szociális Alap társfinanszírozásával valósul meg.. TÁMP /2/A/KMR

2 Semmelweis University BIEMISTRY Metabolism of nucleotides (ukleotidok metabolizmusa) Raymund Machovich. TÁMP /2/A/KMR

3 Lecture objectives To learn: 1) Importance of nucleotide synthesis 2) Synthesis of purine ring, formation of AMP and GMP 3) Significance of phosphoribosyl-pyrophosphate synthetase 4) Regulation of ATPand GTP synthesis 5) Salvage ways of purine nucleotide synthesis 6) Pyrimidine synthesis 7) Synthesis of deoxyribonucleotides and its control 8) rigins of deoxythymidilate: Thymidylate synthase, thymidine kinase 9) Some anticancer drugs 10) Degradation of purine bases urate formation and its importance TÁMP /2/A/KMR

4 ucleotide structures 2 Syn - - P Anti ester bond -glicoside bond ucleotide: Adenosine 5'-monophosphate (AMP, adenylate, adenyl acid) ucleoside: ribose (R) -base (B) R Base: (purine-pyrimidine) B B Adenosine Adenine DS RS ATP camp AD UDP-galactose TÁMP /2/A/KMR

5 ucleotide metabolism Diet ucleotides Resynthesis Biosynthetic Intermediers: UDP-glucose DP-diacilglicerol Redox systems oenzymes oa, AD, FAD Regulation Adenosine ADP camp cgmp Energy ATP Informations: RA DA Various cells TÁMP /2/A/KMR

6 Diet: DS, RS Mono-(oligo-)nucleotides Ribose (R) Deoxyribose (dr)- nucleases Phosphatases ucleosides* Pi ucleosidases B (d)r Purine- Pyrimidinebases R dr Reuse * Thymidine 14 Uridine 3 for DA and RA synthesis TÁMP /2/A/KMR

7 Synthesis of purine ring 10 Formyl- TF Asp Gly Formyl-TF 4 1 Gln TÁMP /2/A/KMR

8 P R ATP AMP P R PP atalytic subunit Regulator subunit IMP AMP GMP PRPP-synthetase Regulator subunit breakdown TÁMP /2/A/KMR

9 Purine ring is synthesized on ribose-phosphate = 5 - P Ribose- 5 - phosphate ATP PRPP - synthetase AMP GMP IMP AMP = α - P 2 P P 5 Phosphoribosyl 1 pyrophosphate (PRPP) TÁMP /2/A/KMR

10 Glu Gln Gln-PRPP-amidotransferase - P 2 2 β 5 Phosphoribosyl 1 amine PPi Azaszerin (tumor chemotherapy) (Gln analog) TÁMP /2/A/KMR

11 2 Gly Pi ATP ADP 2 2 Ribose - P Phosphoribosyl glycinamide synthetase Ribose - P Glycinamide ribonucleotide 10 Formyl TF Phosphoribozyl glycinamide transferase TF Formylglycinamide ribonucleotide TÁMP /2/A/KMR

12 2 ADP ATP 2 2 Ribose P Formylglycin amidine ribonucleotide ATP Glu Gln synthetase 2 Ribose - P Formylglycinamide ribonucleotide Aminoimidazole TÁMP /2/A/KMR

13 synthetase ADP 2 2 carboxylase 2 Ribose- P 5 Aminoimidazole 4 carboxy ribonucleotide R ibose- P 5 aminoimidazole ribonucleotide Asp ATP synthetase ADP Succinylocarboxamide ribonucleotide TÁMP /2/A/KMR

14 ADP 5 Aminoimidazole 4 succinylcarboxamide ribonucleotide 2 2 Adenylosuccinate lyase R ibose- P Aminoimidasole carboxamide TÁMP /2/A/KMR

15 Fumarate 10 Formyl TF TF 2 2 Ribóz- P Transferase 2 Ribose- P 5 Aminoimidazole 4 carboxamide ribonucleotide 5 Formylaminoimidazole 2 carboxamide ribonucleotide IMP synthase TÁMP /2/A/KMR

16 IMP synthase PRPP kinase }Purine ring ypoxantine Ribose- P Inozinate (IMP) AMP GMP TÁMP /2/A/KMR

17 AMP and GMP synthesis IMP Adenylosuccinate synthetase AMP GDP GTP Pi Adenylosuccinate Asp R - P 2 AD AD IMP dehydrogenase GMP Xanthylate TÁMP /2/A/KMR

18 2 R - P R - P Adenylosuccinate Xanthylate TÁMP /2/A/KMR

19 ATP Gln 2 Fumarate Adenylosucccinate lyase AMP PPi GMP synthetase Glu 2 = R - P ATP GTP 2 = R - P Gln analogous Adenylate AMP Guanylate GMP TÁMP /2/A/KMR

20 Ribose 5 -P PRPP Transferase Synthetase Feedback controls of biosynthesis of purine nucleotides PR-amine ATP ATP ATP ATP IMP Synthetase Dehydrogenase Adenylo GTP succinate Xanthylate ATP ATP AMP GMP GTP TÁMP /2/A/KMR

21 = - -P 2 - = P P Purine nucleotides can be re-used ( Salvage ways ) Ө 2 PRPP Adenosine-phosphoribosyl transferase Adenine Adenylate (AMP) PPi R - P TÁMP /2/A/KMR

22 ypoxantine + PRPP ypoxantine-guaninephosphoribosyl transferase PPi Guanine + PRPP PPi IMP AMP, GMP, IMP inhibit their own syntheses 2 R - P R - P GMP TÁMP /2/A/KMR

23 A R (G R) + Adenosine kinase ATP ADP AMP (GMP) A: adenine G: guanine R: ribose TÁMP /2/A/KMR

24 arbamoyl phosphate 2 - P - Pyrimidine syntheses Asp Glu 2ADP arbamoyl-phosphate synthetase (kda 240) Different carbamoylphosphate synthetases. For pyrimidine: Gln in cytosol For urea: + 4 in mitochondria Gln - 3 2ATP UMP TÁMP /2/A/KMR

25 2 -P - - arbamoyl - P Aspartate transcarbamylase arbamoyl-phosphate synthase Mr AD Dihydroorotase Aspartate - transcarbamoylase Pi 2 2 carbamoyl-aspartate 2 2 Asp Dihydroorotase 2 Dihydroorotate dehydrogenase 2 Dihydroorotate AD AD rotate TÁMP /2/A/KMR

26 rotate rotate aciduria Transferase PRPP PPi rotate-phosphorybosyltransferase = - -P 2 - Decarboxylase ereditary breakdown or azauridine (anticancer) Th: uridine rotidylate rotidylate decarboxylase Uridylate (UMP) TÁMP /2/A/KMR

27 Ribose P UTP (uridine- triphosphate) ADP ATP ADP ATP UDP ucleoside UMPdiphosphate kinase kináse UMP rotidylate decarboxylase 2 ATP ADP 2 Gln 2 TP synthetase Glu TP (cytidine triphosphate) Ribose P Uridylate UMP Uridine monophosphate Ribose P P P TÁMP /2/A/KMR

28 Deoxyribonucleotide synthesis 5 P - P Base ADP 2 Ribonucleotide reductase: Its substrate: ribonucleotide diphosphate (BDP) ε ADP S S P - P 2 S enzime: BDP + ε S S Base dbdp + 2 TÁMP /2/A/KMR

29 Ribonucleotide reductase Regulation B1 B1 ATP datp B2 Fe Fe 3+ S S B2 Substrates: ADP DP UDP GDP TÁMP /2/A/KMR

30 ATP DP UDP Regulation of ribonucleotide reductase ddp dtp dudp dttp GDP dgdp dgtp ADP dadp datp TÁMP /2/A/KMR

31 = P dump dr Deoxythymidylate (dtmp) synthesis: Uridine-way methylene - TF Gly Thymidylate synthase Ser TF DF = P ADP Dihydrofolate reductase ADP 3 dr dtmp TÁMP /2/A/KMR

32 Deoxythimidylate (dtmp) synthesis: Thymidine-way 3 = 2 ATP Thymidine kinase ADP 3 = -P- 2 DA-degradation - cellular -diet dt (deoxythimidine) dtmp (Deoxythymidine-monophosphate) dt 3, 14 DA synthesis TÁMP /2/A/KMR

33 F - Uracil Incorporated into RA F- UDP, F - dudp Fluoro deoxyuridylate (F dump) - F P -dr Anticancer drugs UDP Ribonucleotide reductase dump dump Thymidilate - synthase Gly Ser, 5 10 Methylene TF DF TF analogues: ompatitive inhibitors (K i 10-9 M) Aminopterin Methotrexate ADP ADP Dihydrofolate reductase TF 2 - F dtmp ATP ATP TP dtdp dttp DA Pi Pi Polymerase S - enzym P -dr dt Thymidine kinase Kinases and phosphatases TÁMP /2/A/KMR

34 Pyrimidine and purine analogues 2 S 2 ytosine arabinose 6 mercaptopurine ( Immurán ) ypoxantine + PRPP S IMP DA synthesis is inhibited (dtp analogue) AMP GMP TÁMP /2/A/KMR

35 Degradation of purines PRPP Gln 2 Ribose - P AMP Adenylate deaminase 2-2 Asp GMP IMP Gln Phosphomono esterase Pi Ribose PRPP ypoxanthine phosphoribosyl transferase ypoxanthine Xanthine TÁMP /2/A/KMR

36 Guanine phosphoribsyl transferase IMP GMP ypoxanthine PRPP 2 Phosphomonoesterase Ribose Pi Guanine 2 Guanine deaminase Xanthine 2 Xanthine oxidase 2 2 atalase 2 Uric acid TÁMP /2/A/KMR

37 Degradation of purines: urate formation Xanthine 2 2 Xanthine oxidase 2 2 atalase 2 Uric acid (enol) Uric acid (keto) + Urate (low solubility) Gout, Kidney stone Allantoin urea TÁMP /2/A/KMR

38 igh level of urate results in deposition of sodium urate crystals AMP B or decreased A: IMP igh level of uricacid results in its deposition in kidney and joint (inflamed and painful) ypoxanthine ypoxanthine guaninephosphoribozyl transferase PRPP ATP Ribose 5 P B PRPPsynthetase (regulator subunit defect) Xanthine - oxidase Xanthineoxidase Xanthine Urate GMP A Guanine A Genetic lack: Lesch yhan syndrome Bizarre reactions: Self destructive tendencies (biting off their fingers, lip, toes), bad coordination, mental retardardation TÁMP /2/A/KMR

39 Treatment of gout Th: Allopurinol Xanthine oxidase Urate Xanthine oxidases are inhibited (xanthine and hypoxanthine are more soluble than uric acid) joints kidney ypoxanthine Allopurinol Urate is decreased, PRPP not TÁMP /2/A/KMR

40 igh urate level may be useful : Urate level of the human is 10-fold higher than in monkey a factor for the longer life time. Urate is an antioxaidant (like Vitamin E, bilirubin, etc). TÁMP /2/A/KMR

41 Adenosine-deaminase Its lack leads to a 100-fold increase in datp, which inhibits ribonucleotide reductase. The increase in datp, thus results in decrease of other deoxinucleotides necessary for DA synthesis in T and B lymphocytes. Its hereditary deficiency affects the immune system: SID-syndrome (sever combined immundeficiency). It is also called on IV AIDS, because of similar symptoms. TÁMP /2/A/KMR

42 Summary ucleotide metabolism is discussed from the viewpoint of their synthesis (because their amount is not enough in the diet) and they degradation (because they incorrect elimination causes pathological conditions)

43 Recommended literature Machovich R. A nucleotidok anyagcseréje rvosi Biokémia, Medicina kiadó, pp TÁMP /2/A/KMR

44 What is the role of nucleotides? 1) ydrolysis of PP bound of ATP to drive reactions that require an input of energy 2) Building blocks of DA and RA 3) omponenet of coenzymes 4) Second messengers 5) Allosteric effectors of metabolic procesess A: 1,2,5 B:3,4 : all D:2,4,5 E: 1,2

45 orrect answere for test question: TÁMP /2/A/KMR

46 Which of the compound(s) below is/are allosteric inhibitor(s) of PRPP amidotransferase? 1) ATP 2) IMP 3) PRPP 4) AD A: 1,2,3,4, B: 1,2,3 : 2 D: 2,3 E: 1 TÁMP /2/A/KMR

47 orrect answere for test question: TÁMP /2/A/KMR