Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Metabolism of protein & amino acids 1 A. The physiological & nutritious function of proteins 2 B. nitrogen balance & protein requirement 3 1. nitrogen balance a. concept b. experiment 4 c. 3 conditions nitrogen equilibrium negative nitrogen balance positive nitrogen balance 5 2. minimal requirements of protein 3.essential amino acids and their biological value 6 7 an indicator to valuate the nutritional value of the proteins biological value N的保留值 蛋白质的生理价值= 100 N的吸收量 8 4. Complementary function of proteins B. Digestion ,absorption,& putrefaction of proteins 9 a. digestion digestion diet protein amino acids Proteolytic enzyme 10 b. absorption site mechanism characteristics 11 12 c. putrefaction concept 14 未被消化的蛋白质,未被 吸收的氨基酸,肽 Decarboxylation large intestine 有毒; amine ,H2S indole deamination other: CO2,CH4 hydroxybenzene、 ammonia(NH3)、 Absorption in intestine bacterias Nutriment Fatty acid、vit excrete blood 15 liver • decarboxylation • reductive & deamination 16 17 18 • the sources of ammonia in the intestine 19 blood kidney infiltrate NH2-CO-NH2 (25%)7g liver excrete(20g) NH3 intestine NH2-CONH2 urease (bacterias) 2NH3+CO2(4g) importance sources of blood ammonia----- absorpted from intestine 20 C. general metabolism of amino acids 1. Sketch plan 21 decarboxylation amines Dietary protein Amino acid degradation Tissue protein metabolic pool Synthesis 85% amination of α—keto acids deamination Non essential A.A urea NH3 α—keto acids oxidation Glucose, fats 23 other substances N.EAA 2. deamination of amino acids a.oxidative deamination 1) reaction 24 25 2 ) enzymes • L-amino acid oxidase • D-amino acid oxidase • L-glutamate dehydrogenase 26 27 • characteristics b . transamination 1) reaction 28 29 2) important transamination system. 30 glutamic pyruvic transamination system (glutamic pyruvic transaminase,GPT) (alanine transaminase,ALT) glutamic oxaloacetic transamination systen: (glutamic oxaloacetic transaminase, ,GOT) (aspartate transaminase,AST) 31 ALT COOH-(CH2)2-CH-COOH + CH3-C-COOH NH2 COOH-(CH2)2-C-COOH+CH3-CH-COOH O 丙酮酸 Glu O NH2 α—酮戊二酸 Ala AST COOH-(CH2)2-CH-COOH + CH2COOH NH2 CO-COOH COOH-(CH2)2-C-COOH+CH2-COOH O CH-COOH NH2 Glu 草酰乙酸 α—酮戊二酸 ASP 32 2) enzyme & coenzyme 33 35 3) biological significance & characteristics 36 c. combined deamination 1) reaction 37 38 39 40 2) biological significance & characteristics 41 d. purine nucleotide cycle 1) site 2) reaction 42 43 3) characteristics 44 d. nonoxidative deamination • dehydrate deamination • direct deamination 45 46 3. Metabolism of ammonia a. the sources of ammonia 47 the detail about the sources of ammonia 48 sources of blood ammonia (oxidation of amine ) deamination protein putrefaction Urea cycle in liver&intestine Absorption in intestine Gln Blood ammonia Ala (liver) 49 * protein putrefaction 50 *Urea cycle in liver & intestine blood kidney infiltrate NH2-CO-NH2 (25%)7g liver intestine NH2-CONH2 urease 2NH3+CO2(4g) excrete(20g) NH3 excrete from feces importance sources of blood ammonia----NH4 - absorpted from intestine 51 According to the pH in intestine pH NH3 + H+ NH 4+ excrete pH absorpted to venous blood 52 sources of blood ammonia (oxidation of amine ) deamination protein putrefaction Urea cycle in liver&intestine Absorption in intestine Gln Blood ammonia Ala (liver) 53 * hydrolysis of Gln 54 • the fates of ammonia produced in renal cell excrete to the kidney reabsorption to vein blood 55 According to renal tube pH pH pH NH3 + H+ NH4+ excrete absorpted to venous blood 56 (oxidation of amines) Putrefaction in deamination of A.A small intestine Absorption In small intestine Ammonia in blood GLn Intestine-liver cycle of urea Ala in liver 57 *Ala 58 b. The transportation of ammonia • synthesis & utilize of Gln materials : Glu , NH3 59 energy: ATP enzyme: Gln synthetase reaction: 60 61 product: ,Gln Biological significances 62 • glucose-alanine cycle process 63 64 biological significance 65 (oxidation of amines) Putrefaction in deamination of A.A small intestine Absorption In small intestine Ammonia in blood GLn Intestine-liver cycle of urea Ala in liver 66 c. the fates of ammonia 67 urea Synthesis of non essential A.A or other nitrogen compounds muscle or other tissues NH3 Gln liver muscle Ala 68 1) synthesis of urea---main outlet of ammonia a. site b. process (ornithine cycle ) 69 血 切肝犬 用氨基酸饲养切肝犬 尿素 尿素 尿 氨 尿素 氨基酸 切肾犬 尿素 急性黄色肝委缩 尿素 (-) 氨 氨基酸 尿素 (-) *肝脏是合成尿素最主要的器官 70 72 This cycle included: 1 overall reaction 2 materials 3 stages 4 steps 5 enzymes 73 a. materials 15NH 4Cl Feed dogs 15NH 2 15NH 2 14C=O NaH14CO3 74 b. 3 stages 2ATP ornithine+ NH3+ CO2 citrulline+H20 1ATP citrulline+ NH3 arginine+ H20 arginine+ H20 urea+ ornithine 75 NH2 NH2 C=O (CH2)3 2ATP + NH3+ CO2 CH NH + H2O NH2 (CH2)3 COOH CH NH2 ornithine COOH citrulline 77 NH2 NH2 C=O C=NH 1ATP NH + NH3 NH + H2O (CH2)3 (CH2)3 CH-NH2 CH-NH2 COOH Citrullinc COOH Arginine 78 NH2 C=NH NH2 NH +H2O NH2 + (CH2)3 (CH2)3 C=O CH-NH2 CH-NH2 NH2 COOH COOH Arginine urea Orrnithine 79 materials NH3 (2 molecules) CO2 (1 molecules ) urea products H2O Ornithine intermediates Citrulline arginine 80 c. Intermediate process ( 4 steps, 5 enzymes ) 1) synthesis of carbomoyl phosphate (mitochondria) 81 82 NH3+CO2+H2O+2ATP carbomoyl phosphate synthetase 1 NH2-CO-O~PO32-+Pi 83 • enzyme carbamoyl phosphate synthetase 1 carbamoyl phosphate synthetase II 84 carbomoyl phosphate synthetase carbomoyl phosphate 1 Site mitochondria source of NH3 nitrogen Activator AGA (N-Acetylglutamic acid ) Final Product urea synthetase II cytosol Gln - pyrimidine 85 2) synthesis of citrulline (mitochondria) • enzyme ornithine transcarbomoylase 86 87 3) synthesis of arginine (cytosol) • enzyme Argininosuccinate synthetase,ASAS Argininosuccinate lyase ASAL ASAS------ Key enzyme 88 89 4) cleavage of arginine (cytosol) 90 91 93 d. Overall reaction 3ATP+CO2+2NH3 +H2O NH2-CO-NH2 f. summarize 94 c. Regulation of urea synthesis food enzymes (AGA) intermediates 95 96 d. biological significant of urea synthesis 97 urea Synthesis of non essential A.A or other nitrogen compounds muscle or other tissues NH3 Gln liver muscle Ala 98 4. Metabolism of -keto acids Ala Gln NH3 urea Amination of aketo acids Amino acid -keto acids Conversion of fat,glucose Amination or transamination To form non E.A.A. Via TCA cycle oxidized to CO & 99 2 H2 O 1) Amination or transamination To form non E.A.A. α- ketoglutarate Pyruvate oxaloacetate Glu Ala Asp 100 Glu α- ketoglutarate TCA cycle oxaloacetate Asp 101 2) Conversion to lipids or carbohydrates glycogenic amino acid, such as : Ala、Arg、Asp etc(13 ) ketogenic amino acid such as: leu lys (2) glycogenic & ketogenic amino acids such as : Ilu,Phe,Trp,Tye 102 TCA cycle is the hinge of metabolism of lipids , carbohydrates, proteins 103 * * * * * * * * 104 3) oxidation & provide energy 3. decarboxylation 105 Non E.A.A Amino acids α-keto acids amines TCA cycle Conversion to lipids, carbohydrates 106 Enzymes & coenzyme some important amines 107 a.γ-amino butyric acid (GABA) formation 108 enzyme function metabolic fate 109 b. 5-hydroxy tryptamine or ( serotonin) formation 110 function c. taurine formation 111 d. histamine formation function 112 e. polyamines formation 113 114 D. metabolism of individual amino acids 1. one carbon units 115 Concept kinds 116 117 the carrier of one carbon unites --------------THF 118 the sources & conversion 转甲基酶 NH2-CH——COOH +FH4 (CH2)2 NH2-CH—(CH2)2+N5-CH3-FH4 COOH SH S CH3 120 121 122 function one carbon units & medicine 123 2. metabolism of sulfurcontaining amono acids types 124 Met cystine cysteine,Cys 125 a.Met and Transfer of methyl group S-adenosylmethionine (SAM) 126 Structure of SAM 127 Function of SAM methionine cycle B12 & methionine cycle 128 B12 129 3. metabolism of cystein & cystine structure & characteristics 130 Formation of GSH 131 Catabolism of Cys Cys -NH2 pyruvate NH3 H2S Excrete in uria H2S SO42- PAPS(active sulfate) 132 The structure & function of PAPS ( 3’-phosphoadenosine5’phosphosulfate 133 134 4. metabolism of side chain amino acids Type: Val,Ile,Leu Catabolic process (extrahepatic tissue ) 135 α-ketoacids Val、Ile、Leu α-ketoglutarate Ala Glu NH3 Gln pyruvate Blood liver glyconeogenesis urea 136 5. metabolism of aromatic amino acids Type: Phe,Tyr,Trp Catabolic process (hepatic tissue) 137 Catabolic process of Phe 138 139 Albinism, Phenylketonuria, (PKU) Alkaptonuria BCAA/AAA 3:1 140