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Nucleotides metabolism

Nucleotides metabolism. Enmin Li. Digestion, Ingestion and Degradation of Nuclear acids and Nucleotides and Nucleosides and Bases in Food. Bases/Nucleosides/Nucleotides. Base. Nucleo s ide. Nucleo t ide. Deoxyadenosine 5’-triphosphate (dATP). Adenine. Deoxyadenosine.

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Nucleotides metabolism

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  1. Nucleotides metabolism Enmin Li

  2. Digestion, Ingestion and Degradation of Nuclear acids and Nucleotides and Nucleosides and Bases in Food

  3. Bases/Nucleosides/Nucleotides Base Nucleoside Nucleotide Deoxyadenosine 5’-triphosphate (dATP) Adenine Deoxyadenosine apostrophe

  4. Nucleoproteins, RNA/DNA, Nucleotides, Nucleosides and Basesin Food In stomach Gastric acid and pepsin RNA/DNA, Nucleotides, Nucleosides and Bases In small intestine Endonucleases: RNase and DNase Nucleotides, Nucleosides and Bases Ingestion Small intestine epithelial cells Notes * Nucleotides: AMP, GMP, UMP, CMP, mmol dAMP, dGMP, dCMP, dTMP, mol * Nucleosides: Adenosine, Guanosine, Cytidine, Uridine Deoxyadenosine, Deoxyguanosine, Deoxycytidine, Thymidine * Bases: Adenine, Guanine, Cytosine, Thymine, Uracil

  5. In small intestine cells, liver cells and kidney cells NH4+ NADPH+H+ NADP + + NH3 H2O AMP IMP GMP Deaminase GMP reductase H2O H2O H2O Nucleotidase Nucleotidase Nucleotidase P P P NH4+ H2O Adenosine Inosine Guanosine Deaminase P P ? Nucleosidase Nucleosidase Nucleosidase R-1-P R-1-P Hypoxanthine Adenine Guanine ? H2O+O2 H2O Oxidase Deaminase H2O2 NH4+ Xanthine H2O+O2 Oxidase H2O2 Uric acid

  6. In small intestine cells, liver cells and kidney cells dTMP UMP CMP Nucleotidase Nucleosidase Nucleotidase Nucleosidase Nucleotidase Nucleosidase Uracil Cytosine Thymine Reductase Reductase Dihydrouracil Dihydrothymine Dihydrouracilase Dihydrothyminase β-uraminoisobutyric acid β-uraminopropion β-uraminopropionase β-uraminoisobutyric acidase β-aminoisobutyric acid β-alanine

  7. Tricarboxylic acid cycle Succinyl CoA Uric acid β-aminoisobutyric acid Out of body In kidney Pantothenic acid β-alanine Coenzyme A

  8. The fate of uric acid in the various animals Hypoxanthine Adenine Xanthine Guanine 1 2 3 4 Glyoxylic acid Allantoic acid Uric acid Allantoin Urea Notes: Excreted by 1 Primates, Birds, Reptiles, Insects. 2 Other mammals. 3 Teleost fish. 4 Cartilaginous fish and amphibia 5 Marine invertebrates 5 4NH3 + 2CO2

  9. Hypoxanthine Xanthine Hypoxanthine Allopurinol The uric acid and the gout Out of body In urine Uric acid  Over 0.48 mmol/L, In the plasma Diabetese nephrosis …… Gout, Urate crystallization in joints, soft tissue, cartilage and kidney

  10. AMP deaminase and diabetes Jenkins RL, McDaniel HG, Atkins L. Changes in AMP deaminase activities in the hearts of diabetic rats. Biochim Biophys Acta. 1991 Apr 29;1077(3):379-84 Department of Biology, Samford University, Birmingham, AL 35229. AMP deaminase from normal and diabetic rat hearts was separated on cellulose phosphate and quantitated by HPLC. From soluble fractions three different AMP deaminase activities, according to KCl elution from cellulose phosphate and percent of total activity were: 170 mM (85%), 250 mM (8%) and 330 mM (7%) KCl. The AMP deaminase activity which eluted with 170 mM KCl was resolved to two distinct peaks by HPLC anionic exchange. After 4 weeks of diabetes the heart enzyme profile change to: 170 mM (10%), 250 mM (75%) and 330 mM (15%). Once purified the four activities were kinetically distinct: 170 mM KCl cytosolic, AMP Km = 1.78, stimulated by ATP, GTP, NADP and strongly inhibited by NAD; 170 mM KCl mitochondria AMP Km = 17.9, stimulated by ATP, ADP; 250 mM KCl isozyme, AMP Km = 0.66, stimulated by ADP; and 330 mM KCl isozyme, AMP Km = 0.97, inhibited by ATP, NAD(P).

  11. Nucleotides Biosynthesis Purine Adenine Guanine Cytosine Pyrimidine 1-3 Uracil Thymine • de novo pathway • salvage pathway

  12. Salvage nucleotide biosynthesis pathway Adenine, Guanine, Hypoxanthine, Thymine, Uracil Bases Phosphoribosyl thansferase (APRT, HGPRT) PRPP ATP Nucleosides kinase Adenosine, Guanosine, Cytidine, Uridine, orDeoxy…, Thymidine

  13. Lesch-Nyhan Syndrome (Occurs primarily in males) The metabolic consequences of congenital HGPRT deficiency in Lesch-Nyhan syndrome: • purine synthesis is about increased 200-fold • Increased uric acid • Spasticity(痉挛) • Neurological defects • Aggressive behavior • Self-mutilation(自残)

  14. Hypoxanthine-guanine phosphoribosyl transferase on X chromosome Loss of HGPRT leads to elevated PRPP levels and stimulation of de novo purine synthesis. One ultimate consequence is increased production of uric acid.

  15. De novo nucleotide biosynthesis pathway

  16. The main bases on nucleotides or nucleosides in the tautomeric forms predominant at pH7.

  17. The metabolic origin of the six atoms in the pyrimidine ring Carbamyl-P Aspartate

  18. UTP and CTP biosynthesis kinase kinase UMP UDP UTP ADP ATP ADP ATP

  19. http://www.ncbi.nlm.nih.gov/entrez/viewer.fcgi?db=protein&id=3228248http://www.ncbi.nlm.nih.gov/entrez/viewer.fcgi?db=protein&id=3228248 _ + UDP ATP CTP PRPP UTP The regulatory circuits that control pyrimidine synthesis in E.coli and animals.

  20. 甘氨右中站 谷氮坐两边 左上天冬氨 头顶二氧碳 二八俩叶酸 Glycine Aspartate N10-formyl-THF N10-formyl-THF Glutamine (amide-N) The metabolic origin of the nine atoms in the purine ring First, synthesis Inosine-5'-Monophosphate, IMP

  21. OH ATP 0 AMP Gln:PRPP amidotransferase 5-磷酸核糖胺,PRA

  22. 甘氨酰胺核苷酸

  23. 甲酰甘氨酰胺核苷酸

  24. 甲酰甘氨咪核苷酸

  25. 5-氨基咪唑核苷酸

  26. Carboxyaminoimidazole ribonucleotide (CAIR) 5-氨基-4-羧基咪唑核苷酸

  27. Carboxyaminoimidazole ribonucleotide (CAIR) 7 5-氨基-4-(N-琥珀酸) -甲酰胺咪唑核苷酸

  28. 8 5-氨基-4-甲酰胺咪唑核苷酸

  29. 9 5-甲酰胺基-4-甲酰胺咪唑核苷酸

  30. 10

  31. Second, Making AMP and GMP

  32. kinase kinase kinase kinase ADP, ATP, GDP and GTP biosynthesis ATP AMP ADP GDP GTP GDP GTP GTP GDP GMP ADP ATP ADP ATP

  33. Ribose-5-phosphate Regulation of De Novo Synthesis of Purine Nucleotides Ribose-5-phosphate Pyrophosphokinase + PRPP Key Step 5-Phosphoribosylamine Inactive Active 2 Gln:PRPP amidotransferase IMP Adenylosuccinate XMP AMP GMP Adenylosuccinate Synthesase IMP dehydrogenase ADP GDP ATP GTP

  34. Interconversion of Purine nucleotides GMP AMP NADPH NH3 NH3 Adenine Deaminase Guanine Reductase NADP+＋ AMPS （腺苷酸代琥珀酸） XMP IMP

  35. Deoxyribonucleotide Biosynthesis Adenine Guanine Cytosine Uracil Thymine × NADPH dTTP? dNTP DNA Kinase dNMP Phosphorylase

  36. dUDP dCMP dCDP dUMP N5,N10-methylene-tetrahydrofolic Acid dTMP synthetase ATP ATP dTTP dTMP dTDP ADP ADP Deoxythymidine kinase ADP ATP Deoxythymidine

  37. Ribonucleotides can be converted to deoxyribonucleotides by ribonucleotide reductase 86-kD2 58-kD 12-kD 43.5-kD 2 The (-S-S-)/(-SH HS-) oxidation-reduction cycle involving ribonucleotide reductase, thioredoxin, thioredoxin reductase and NADPH.

  38. GSSG 2SH NDP Reductase Glutaredoxin GSSG 2GSH

  39. 225 462 Allosteric regulation Ribonucleotide reductase

  40. The free radical mechanism of ribonucleotide reduction

  41. http://www.ncbi.nlm.nih.gov/entrez/viewer.fcgi?db=protein&id=2507304http://www.ncbi.nlm.nih.gov/entrez/viewer.fcgi?db=protein&id=2507304 1 mnqnllvtkr dgsterinld kihrvldwaa eglhnvsisq velrshiqfy dgiktsdihe 61 tiikaaadli srdapdyqyl aarlaifhlr kkaygqfepp alydhvvkmv emgkydnhll 121 edyteeefkq mdtfidhdrd mtfsyaavkq legkylvqnr vtgeiyesaq flyilvaacl 181 fsnypretrl qyvkrfydav stfkislptp imsgvrtptr qfsscvliec gdsldsinat 241 ssaivkyvsq ragiginagr iralgspirg geafhtgcip fykhfqtavk scsqggvrgg 301 aatlfypmwh levesllvlk nnrgvegnrv rhmdygvqin klmytrllkg editlfspsd 361 vpglydaffa dqeeferlyt kyekddsirk qrvkavelfs lmmqerastg riyiqnvdhc 421 nthspfdpai apvrqsnlcl eialptkpln dvndengeia lctlsafnlg ainnldelee 481 lailavrald alldyqdypi paakrgamgr rtlgigvinf ayylakhgkr ysdgsannlt 541 hktfeaiqyy llkasnelak eqgacpwfne ttyakgilpi dtykkdldti aneplhydwe 601 alresikthg lrnstlsalm psetssqisn atngiepprg yvsikaskdg ilrqvvpdye 661 hlhdayellw empgndgylq lvgimqkfid qsisantnyd psrfpsgkvp mqqllkdllt 721 aykfgvktly yqntrdgaed aqddlvpsiq ddgcesgack i 225 439 462 Ribonucleoside diphosphate reductase 1 subunit alpha

  42. Regulation of dNTP Synthesis

  43. Chemotherapeutic Agents for cancers 1. Analogs of purine OH N N OH guanine H2N N N N N H OH N N H N N inosine N N 8-azoguanine N H2N SH H N N SH N N N N H 6-mercaptoguanine H2N N 6-mercaptopurine N H

  44. 2. Analogs of amino acids O NH2 H2N—C—CH2—CH2—CH—COOH Glutamine, Gln O NH2 N+ —N—CH2—C—O—CH2—CH—COOH Azaserine（重氮乙酰丝氨酸） NH2 O N+ —N—CH2—C—CH2—CH2—CH—COOH Diazonorleucine (6-重氮-5-氧正亮氨酸)

  45. 3. Analogs of Folic acid N5,N10-methylene-FH4 (N5,N10-亚甲基四氢叶酸) Aminopterin （氨喋呤） R=H，Methotrexate（氨甲喋呤）R=CH3

  46. Azaserine MTX 6MP PRPP FGAR GAR FGAM AICAR PRA Gln MTX Azaserine FAICAR AMP A PPi PRPP 6MP 6MP IMP I 6MP PPi PRPP 6MP Azaserine GMP G The mechanism of the Chemotherapeutic Agents-1

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