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Amino acid catabolism

Sections/problems listed with an asterisk (*) do not discuss the exact reaction indicated, but do discuss a closely related reaction.

 

  • Transaminase (EC 2.6.1.1, EC 2.6.1.2) Section 14.4E
  • Carbamoyl phosphate synthetase (EC 6.3.4.16) P12. 4

 

Urea cycle:
  • Ornithine transcarbamylase (EC 2.1.3.3) Section 12.2A,B*
  • Argininosuccinate synthetase (EC 6.3.4.5) Section 12.6, Section 14.1D
  • Arginosuccinate lyase (EC 4.3.2.1) Section 14.1D
  • Arginase (EC 3.5.3.1) P12.16

 

Glycine  (glycine cleavage system)

  • Glycine dehydrogenase (decarboxylating) (EC 1.4.4.2) P16.4b
  • Aminomethyltransferase (EC 2.1.2.10) C11.5

 

Alanine (to pyruvate and glutamate):

  • Alanine transaminase (EC 2.6.1.2) Section 14.4E

 

Serine

  • (to pyruvate): Serine dehydratase (EC 4.3.1.17) Section 13.1B, Section 14.4F
  • (to glycine): Serine hydroxymethyltransferase (EC 2.1.2.1) Section 11.6D, Section 14.4D

 

Cysteine (to pyruvate)

  • Cysteine dioxygenase (EC 1.13.11.20) not covered
  • Aspartate aminotransferase (2.6.1.1) Section 14.4E

 

Threonine

pathway 1 (to glycine and acetyl CoA):

  • Threonine dehydrogenase (EC 1.1.1.103) Section 16.4D*
  • Glycine C-acetyltransferase (EC 2.3.1.29) Section 14.4D

pathway 2 (to glycine and acetaldehyde):

  • Threonine aldolase (EC 4.1.2.5) Section 14.4D*, P14.10a

pathway 3 (to succinyl-CoA via propionyl CoA):

  • Threonine dehydratase (EC 4.3.1.19) P14.2
  • 2-oxobutanoate dehydrogenase (EC 1.2.4.4) Section 16.12B*
  • Propionyl-CoA carboxylase (EC 6.4.1.3) Section 13.5D*, P13.2*
  • Methylmalonyl-CoA mutase (EC 5.4.99.2) not covered

 

Tryptophan (to glutaryl-CoA)

  • Tryptophan 2,3-dioxygenase (EC 1.13.11.11) not covered
  • Arylformamidase (EC 3.5.1.19) Chapter 12*
  • Kynurenine 3-monooxygenase (EC 1.14.13.9) Section 16.10
  • Kynurenimase (EC 3.7.1.3) P14.10b
  • 3-hydroxyanthranilate 3,4-dioxygenase (EC 1.13.11.6) not covered
  • Aminocarboxymuconate-semialdehyde decarboxylase (EC 4.1.1.45) Section 13.5C*, P13.5a
  • 2-aminomuconate semialdehyde dehydrogenase (EC 1.2.1.32) Section 16.4D*, P16.2a
  • 2-aminomuconate deaminase (EC 3.5.99.5) Section 11.6*, P11.1
  • 2-oxoglutarate dehydrogenase (EC 1.2.4.2) Section 16.12B*

 

Asparagine (to aspartate)

  • Asparaginase (EC 3.5.1.1) Chapter 12*

 

Aspartate

  • (to oxaloacetate): Aspartate transaminase (EC 2.6.1.1) Section 14.4E
  • (to fumarate): Aspartate-ammonia lyase (EC 4.3.1.1) P14.3

 

Glutamine (to glutamate)

  • Glutaminase (EC 3.5.1.2) Chapter 12

 

Glutamate (to alpha-ketoglutarate):

  • Glutamate dehydrogenase (EC 1.4.1.2) Section 16.4D

 

Arginine (to glutamate):

  • Arginase (EC 3.5.3.1) P12.16b
  • Ornithine transaminase (EC 2.6.1.13) Section 14.4E*
  • Glutamate semialdehyde dehydrogenase (EC 1.2.1.41) Section 16.4D

 

Histidine (to glutamate):

 

  • Histidine ammonia-lyase (EC 4.3.1.3) C14.5
  • Urocanate hydratase (EC 4.2.1.49) C16.1
  • Imidazolonepropionase (EC 3.5.2.7) Chapter 12*
  • Formimidoylglutamase (EC 3.5.3.8) P11.13b

 

Valine, isoleucine, leucine:

  • Branched chain amino acid transaminase (EC 2.6.1.42) Section 14.4E*
  • Branched chain ketoacid dehydrogenase complex (EC 1.2.4.4) Section 16.12B*
  • Acyl CoA dehydrogenase (eg. EC 1.3.99.13) Section 16.5C, Section 17.3C

valine (to succinyl CoA):

  • Enoyl-CoA hydratase (EC 4.2.1.17) P16.9
  • 3-hydroxyisobutyryl-CoA hydrolase (EC 3.1.2.4) P16.9
  • 3-hydroxyisobutyrate dehydrogenase (EC 1.1.1.31) P16.9
  • Methylmalonate-semialdehyde dehydrogenase (1.2.1.27) P16.9
  • Propionyl-CoA carboxylase (EC 6.4.1.3) Section 13.5D*, P13.2*
  • Methylmalonyl-CoA mutase (EC 5.4.99.2) not covered

isoleucine (to succinyl CoA and acetyl CoA):

  • Enoyl-CoA hydratase (EC 4.2.1.17) P16.9
  • Methyl-hydroxybutyryl CoA dehydrogenase (EC 1.1.1.178) Section 16.4*
  • 3-ketoacyl-CoA thiolase (EC 2.3.1.16) Section 13.4B*
  • Propionyl-CoA carboxylase (EC 6.4.1.3) Section 13.5D*, P13.2*
  • Methylmalonyl-CoA mutase (EC 5.4.99.2) not covered

leucine (to acetyl CoA)

  • Methylcrotonoyl-CoA carboxylase (EC 6.4.1.4) Section 13.5*
  • Methylglutaconyl-CoA hydratase (EC 4.2.1.18) Section 14.1*
  • Hydroxymethylglutaryl-CoA lyase (EC 4.1.3.4) Section 13.3C*

 

Methionine (to cysteine and succinyl-CoA):

  • Methionine adenosyltransferase (EC 2.5.1.6) E9.1
  • Methyltransferase (eg. 2.1.1.37) Section 9.1A
  • Adenosylhomocysteinase (EC 3.3.1.1) Section 14.1A
  • Cystathionine beta-synthase (EC 4.2.1.22) Section 14.4G*
  • Cystathionine gamma-lyase (EC 4.4.1.1) Section 14.4G
  • 2-oxobutanoate dehydrogenase (EC 1.2.4.4) Section 16.12B*
  • Propionyl-CoA carboxylase (EC 6.4.1.3) Section 13.5D*, P13.2*
  • Methylmalonyl-CoA mutase (EC 5.4.99.2) not covered

 

Lysine (to glutaryl-CoA)

  • Saccharopine dehydrogenase (EC 1.5.1.8) P11.6, P16.7a
  • Saccharopine reductase (EC 1.5.1.10) P11.7, P16.7b
  • Aminoadipate-semialdehyde dehydrogenase (EC 1.2.1.31) Section 16.4D*
  • 2-aminoadipate transaminase (EC2.6.1.39) Section 14.4E*
  • 2-oxoglutarate dehydrogenase (EC 1.2.4.2) Section 16.12B*

 

Phenylalanine (to tyrosine):

  • Phenylalanine hydroxylase (EC 1.14.16.1) not covered

 

Tyrosine (to fumarate and acetoacetate):

  • Tyrosine transaminase (EC 2.6.1.5) Section 14.4E*
  • 4-hydroxyphenylpyruvate dioxygenase (EC 1.13.11.27) not covered
  • Homogentisate 1,2-dioxygenase (EC 1.13.11.5) not covered
  • Maleylacetoacetate isomerase (EC 5.2.1.2) Section 14.2A*
  • Fumarylacetoacetase (EC 3.7.1.2) Section 13.4B*

 

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