DNA ligase (ATP) activity

Definition

Target type: molecularfunction

Catalysis of the reaction: ATP + deoxyribonucleotide(n) + deoxyribonucleotide(m) = AMP + diphosphate + deoxyribonucleotide(n+m). [EC:6.5.1.1]

DNA ligase (ATP) activity is a crucial molecular function in DNA replication, repair, and recombination. It catalyzes the joining of two DNA strands by forming a phosphodiester bond between the 5'-phosphate of one strand and the 3'-hydroxyl group of the other strand. This process requires the hydrolysis of ATP, which provides the energy for the reaction. DNA ligases typically act on nicked DNA molecules, where the two strands are discontinuous, but some ligases can also join blunt-ended DNA fragments. The specific mechanism involves several steps: 1) Binding of the ligase to the nicked DNA, recognizing the 5'-phosphate and 3'-hydroxyl groups. 2) Adenylation of the ligase, where an AMP molecule from ATP is transferred to a lysine residue in the active site. 3) Transfer of the AMP moiety from the ligase to the 5'-phosphate of the nick, forming a ligase-adenylated DNA intermediate. 4) Formation of the phosphodiester bond between the 5'-phosphate and 3'-hydroxyl groups, releasing the ligase and AMP. DNA ligase activity is essential for maintaining the integrity of the genome and plays a critical role in various cellular processes, including replication, repair, recombination, and chromosomal stability.'
"

Proteins (1)

Compounds (2)