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Protein turnover Catabolism of amino acids II
István Léránt
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CATABOLISM OF AMINO ACIDS ‚C’
Pyruvate Acetyl-CoA Acetoacetyl-CoA Alpha-ketoglutarate Succunyl-CoA Fumarate Oxalacetate Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Ketoplastic amino acids Acetyl-CoA Acetoacetyl-CoA Glucoplastic amino acids Pyruvate Alpha-ketoglutarate Succinyl-CoA Fumarate Oxalacetate Gluco- and ketoplastic amino acids Pyruvate Acetyl-CoA Acetoacetyl-CoA Alpha-ketoglutarate Succunyl-CoA Fumarate Oxalacetate Protein turnover. Catabolism of amino acids
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Formation of amphibolic intermediers
Glucoplastic Ketoplastic Gluco- and ketoplastic Ala, Arg, Asp, Cys, Glu, Gly, His, Hyp, Met, Pro, Ser, Thr, Val Leu Ile, Lys, Phe, Trp, Tyr Protein turnover. Catabolism of amino acids
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Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Degradation of Ala Ser Cys Thr results in pyruvate formation Protein turnover. Catabolism of amino acids
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Carbon skeleton is degraded to pyruvate
L-Treonine L-Glycine CO2 + NH4+ Cystine L-Serine Pyruvate L-Alanine L-Cysteine Pyruvate-dehydrogenase Acetil-KoA Protein turnover. Catabolism of amino acids
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Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Degradation of Asp Asn Results in oxaloacetate L-aspartate a-ketoglutarate L-glutamate oxaloacetate Protein turnover. Catabolism of amino acids
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Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Degradation of Gln Glu Pro Arg His Results in formation of a-ketoglutarate Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Degradation of Gln Glu Pro Arg His results in a-ketoglutarate His – precurcor Histamine (biogen amine) Carnosine (dipeptide, brain, muscle) Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Degradation of Gln Glu Pro Arg His results in a-ketoglutarate His – precurcor Histamine (biogen amine) Carnosine (dipeptide, brain, muscle) Histidinaemia, histidinuria Histidase deficiency [histamine] á, [imidazole] á In blood, urine, cerebrospinal fluid Decreased [urocanic acid] Rare, autosomal recessive Asymptomatic, later hyperactivity, impeded speach Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Degradation of Gln Glu Pro Arg His results in a-ketoglutarate His – precursor of Histamine Histamine (biogen amine) Carnosine (dipeptide, brain, muscle) Folic acid Laboratory test in folic acid deficiency Figlu (Form-imino-glutamate) á Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Degradation of Gln Glu Pro Arg His results in a-ketoglutarate Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Degradation of Gln Glu Pro Arg His results in a-ketoglutarate Proline oxydase, pyrroline-5-carboxylate dehydrogenase Hyperprolinaemia I Hyperprolinaemia I: prolin-dehydrogenase (Hz –symptoms of hyperprolinaemia) Hyperprolinaemia II Hyperprolinaemia II: Glutamate-g-semialdehyd dehydrogenase (hyperhydroxypolinaemia, Hz absence of symptoms of hyperprolinaemia) , Protein turnover. Catabolism of amino acids
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Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Catabolism results in formation of succinyl-CoA Met Val Ile ß-oxidation of fatty acids of odd-numbered chain Cholesterol – bile acids Biotin Vit B12 Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Met a-ketobutyrate CATABOLISM OF AMINO ACIDS ‚C’ Val Propionyl-CoA Leu Methylmalonyl-CoA Catabolism results in formation of succinyl-CoA Met Val Ile Succinyl-CoA Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Catabolism results in formation of succinyl-CoA Met Val Ile Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Hyperhomocysteinemia / hyperhomocysteinaemia [homocysteine] blood áá Pyridoxine / (B6) folic acid (B9) Vitamin B12 Deficiency of methylentetrahydrofolate reductase methioninsynthetase Risk factor for recurrent venous thrombosis Met Val Ile Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Leu Val Ile Transaminase activity a-ketoacid-dehydrogenase a-ketoacid derivative CO2 + Acyl-CoA tioester a,ß-unsaturated acyl-CoA thioester ß-Hydroxymethyl- Glutaryl-CoA Leu Propionyl-CoA + Acetyl-Coa Ile Succinyl-CoA Val Protein turnover. Catabolism of amino acids
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CATABOLISM OF AMINO ACIDS ‚C’
Branched alpha-keto acid dehydrogenase multienzym complex Alpha-ketoglutarate dehydrogenase PDH PDH (Maple Syrup Urine Disease) Methylmalonic aciduria Propionic acidemia Protein turnover. Catabolism of amino acids
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