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CATH Superfamily 3.30.1490.70

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: 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 13: DNA ligase 3

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
DNA ligase (ATP). [EC: 6.5.1.1]
ATP + (deoxyribonucleotide)(n)-3'-hydroxyl + 5'-phospho- (deoxyribonucleotide)(m) = (deoxyribonucleotide)(n+m) + AMP + diphosphate.
  • The enzyme catalyzes the ligation of DNA strands with 3'-hydroxyl and 5'-phosphate termini, forming a phosphodiester and sealing certain types of single-strand breaks in duplex DNA.
  • Catalysis occurs by a three-step mechanism, starting with the activation of the enzyme by ATP, forming a phosphoramide bond between adenylate and a lysine residue.
  • The adenylate group is then transferred to the 5'-phosphate terminus of the substrate, forming the capped structure 5'-(5'-diphosphoadenosine)-(DNA).
  • Finally, the enzyme catalyzes a nucleophilic attack of the 3'-OH terminus on the capped terminus, which results in formation of the phosphodiester bond and release of the adenylate.
  • RNA can also act as substrate, to some extent.
  • Cf. EC 6.5.1.2, EC 6.5.1.6 and EC 6.5.1.7.
 1 Q54QM4
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