ENZYME entry: EC 6.5.1.7

Accepted Name

DNA ligase (ATP, ADP or GTP)

Reaction catalysed

ATP + (deoxyribonucleotide)n-3'-hydroxyl + 5'-phospho-(deoxyribonucleotide)m = (deoxyribonucleotide)n+m + AMP + diphosphate
ADP + (deoxyribonucleotide)n-3'-hydroxyl + 5'-phospho-(deoxyribonucleotide)m = (deoxyribonucleotide)n+m + AMP + phosphate
GTP + (deoxyribonucleotide)n-3'-hydroxyl + 5'-phospho-(deoxyribonucleotide)m = (deoxyribonucleotide)n+m + GMP + diphosphate

Comment(s)

The enzymes from the archaea Hyperthermus butylicus and Sulfophobococcus zilligii are active with ATP, ADP or GTP.
They show no activity with NAD(+).
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, ADP, or GTP, forming a phosphoramide bond between adenylate/guanylate and a lysine residue.
The nucleotide is then transferred to the 5'-phosphate terminus of the substrate, forming the capped structure 5'-(5'-diphosphoadenosine/guanosine)-[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 nucleotide.
Different from EC 6.5.1.1 and EC 6.5.1.6, which cannot utilize GTP.

Cross-references

BRENDA

EC2PDB

ExplorEnz

PRIAM enzyme-specific profiles

KEGG Ligand Database for Enzyme Nomenclature

IUBMB Enzyme Nomenclature

IntEnz

MEDLINE

MetaCyc

Rhea expert-curated reactions

UniProtKB/Swiss-Prot

Q9YD18, DNLI_AERPE	A2BJX6, DNLI_HYPBU	A3DP49, DNLI_STAMF
D2CJS7, DNLI_SULZI

All UniProtKB/Swiss-Prot entries referenced in this entry, with possibility to download in different formats, align etc.

All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 6.5.1.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 6.5.-.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 6.-.-.-