CATH Classification

Domain Context

CATH Clusters

Superfamily 3.30.1490.70
Functional Family

Enzyme Information
DNA ligase (ATP).
based on mapping to UniProt P00969
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, EC and EC

UniProtKB Entries (1)

Enterobacteria phage T7
DNA ligase

PDB Structure

External Links
Organism Escherichia
Primary Citation
Crystal structure of an ATP-dependent DNA ligase from bacteriophage T7.
Subramanya, H.S., Doherty, A.J., Ashford, S.R., Wigley, D.B.