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CATH Superfamily 3.40.640.10

Type I PLP-dependent aspartate aminotransferase-like (Major domain)

The name of this superfamily has been modified since the most recent official CATH+ release (v4_4_0). At the point of the last release, this superfamily was named:

"
Type I PLP-dependent aspartate aminotransferase-like (Major domain)
".

Functional Families

Overview of the Structural Clusters (SC) and Functional Families within this CATH Superfamily. Clusters with a representative structure are represented by a filled circle.
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FunFam 9: Cystathionine gamma-synthase homolog

There are 6 EC terms in this cluster

Please note: EC annotations are assigned to the full protein sequence rather than individual protein domains. Since a given protein can contain multiple domains, it is possible that some of the annotations below come from additional domains that occur in the same protein, but have been classified elsewhere in CATH.

Note: The search results have been sorted with the annotations that are found most frequently at the top of the list. The results can be filtered by typing text into the search box at the top of the table.

EC Term Annotations Evidence
Cystathionine gamma-synthase. [EC: 2.5.1.48]
O(4)-succinyl-L-homoserine + L-cysteine = L-cystathionine + succinate.
  • Also reacts with H(2)S and methanethiol as replacing agents, producing homocysteine and methionine, respectively.
  • In the absence of thiol, can also catalyze beta,gamma-elimination to form 2-oxobutanoate, succinate and ammonia.
  • Formerly EC 4.2.99.9.
 181 A0A045IYZ7 A0A045IYZ7 A0A045IYZ7 A0A045IYZ7 A0A045IYZ7 A0A045IYZ7 A0A045IYZ7 A0A045IYZ7 A0A045IYZ7 A0A045IYZ7
(171 more...)
Cystathionine gamma-lyase. [EC: 4.4.1.1]
L-cystathionine + H(2)O = L-cysteine + NH(3) + 2-oxobutanoate.
  • The enzyme cleaves a carbon-sulfur bond, releasing L-cysteine and an unstable enamine product that tautomerizes to an imine form, which undergoes a hydrolytic deamination to form 2-oxobutanoate and ammonia.
  • The latter reaction, which can occur spontaneously, can also be catalyzed by EC 3.5.99.10.
  • Also catalyzes the conversion of L-homoserine to 2-oxobutanoate and ammonia, of L-cystine to thiocysteine, pyruvate and ammonia, and of L-cysteine to pyruvate, hydrogen sulfide and ammonia.
  • Formerly EC 4.2.1.15.
 35 A0A164WZS0 A0A164WZS0 A0A164WZS0 A0A164WZS0 A0A164WZS0 A0A2K6ATS8 A0A2K6ATS8 A0A410R352 A0A410R352 A0A410R352
(25 more...)
Homocysteine desulfhydrase. [EC: 4.4.1.2]
L-homocysteine + H(2)O = H(2)S + NH(3) + 2-oxobutanoate.
  • The enzyme cleaves a carbon-sulfur bond, releasing hydrogen sulfide and an unstable enamine product that tautomerizes to an imine form, which undergoes a hydrolytic deamination to form 2-oxobutanoate and ammonia.
  • The latter reaction, which can occur spontaneously, can also be catalyzed by EC 3.5.99.10.
 30 A0A164WZS0 A0A164WZS0 A0A164WZS0 A0A164WZS0 A0A164WZS0 A0A410R352 A0A410R352 A0A410R352 A0A410R352 A0A410R352
(20 more...)
Cysteine-S-conjugate beta-lyase. [EC: 4.4.1.13]
An L-cysteine-S-conjugate + H(2)O = RSH + NH(3) + pyruvate.
  • A pyridoxal 5'-phosphate protein.
  • The enzyme is promiscuous regarding the moiety conjugated to L-cysteine, and can accept both aliphatic and aromatic substitutions.
  • The enzyme cleaves a carbon-sulfur bond, releasing a thiol and an unstable enamine product that tautomerizes to an imine form, which undergoes a hydrolytic deamination to form pyruvate and ammonia.
  • While bacteria and plants have dedicated enzymes, all of the animal enzymes discovered thus far are bifunctional, most of which also act as aminotransferases.
  • Formerly EC 4.4.1.6 and EC 4.4.1.8.
 19 A0A0B0DY77 A0A0B0DY77 A0A1B2AV35 A0A1B2AV35 A0A1B2AV35 B9DGA0 B9DGA0 L8AET3 L8AET3 L8AET3
(9 more...)
Methionine gamma-lyase. [EC: 4.4.1.11]
L-methionine + H(2)O = methanethiol + NH(3) + 2-oxobutanoate.
  • The enzyme cleaves a carbon-sulfur bond, releasing methanethiol and an unstable enamine product that tautomerizes to an imine form, which undergoes a hydrolytic deamination to form 2-oxobutanoate and ammonia.
  • The latter reaction, which can occur spontaneously, can also be catalyzed by EC 3.5.99.10.
  • The enzyme is involved in L-methionine catabolism.
 5 A5TY55 A5TY55 Q8L0X4 Q8L0X4 Q8RDT4
L-cysteine desulfidase. [EC: 4.4.1.28]
L-cysteine + H(2)O = sulfide + NH(3) + pyruvate.
  • The enzyme from the archaeon Methanocaldococcus jannaschii contains a [4Fe-4S] cluster and is specific for L-cysteine (cf. EC 4.4.1.1).
  • It cleaves a carbon-sulfur bond releasing sulfide and the unstable enamine product 2-aminoprop-2-enoate that tautomerizes to an imine form, which undergoes a hydrolytic deamination to form pyruvate and ammonia.
  • The same reaction can also be catalyzed by some pyridoxal-phosphate proteins (cf. EC 4.4.1.1).
 1 Q8RDT4
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