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CATH Superfamily 3.40.50.880

Class I glutamine amidotransferase (GATase) domain

The name of this superfamily has been modified since the most recent official CATH+ release (v4_3_0). At the point of the last release, this superfamily was: waiting to be named.

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 228: Carbamoyl-phosphate synthase small chain

There are 1 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
Carbamoyl-phosphate synthase (glutamine-hydrolyzing). [EC: 6.3.5.5]
2 ATP + L-glutamine + HCO(3)(-) + H(2)O = 2 ADP + phosphate + L-glutamate + carbamoyl phosphate.
  • The product carbamoyl phosphate is an intermediate in the biosynthesis of arginine and the pyrimidine nucleotides.
  • The enzyme from Escherichia coli has three separate active sites, which are connected by a molecular tunnel that is almost 100 A in length.
  • The amidotransferase domain within the small subunit of the enzyme hydrolyzes glutamine to ammonia via a thioester intermediate.
  • The ammonia migrates through the interior of the protein, where it reacts with carboxyphosphate to produce the carbamate intermediate.
  • The carboxyphosphate intermediate is formed by the phosphorylation of hydrogencarbonate by ATP at a site contained within the N-terminal half of the large subunit.
  • The carbamate intermediate is transported through the interior of the protein to a second site within the C-terminal half of the large subunit, where it is phosphorylated by another ATP to yield the final product, carbamoyl phosphate.
  • Cf. EC 6.3.4.16.
  • Formerly EC 2.7.2.9.
 1 Q58425
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