DNA ligase

(redirected from DNA ligase I)


 [li´gās, lig´ās]
any of a class of enzymes that catalyze the joining together of two molecules coupled with the breakdown of a pyrophosphate bond in ATP or a similar triphosphate.
DNA ligase either of two enzymes that join two double-helical molecules of DNA together to make a longer DNA molecule.
ligase chain reaction a type of DNA amplification that uses DNA ligase to link chains and amplify the template containing the sequence in question.

DNA li·gase

an enzyme that leads to the formation of a phosphodiester bond at a break of one strand in duplex DNA; a part of the DNA repair system.

DNA ligase

an enzyme that catalyses the formation of covalent bonds between adjacent parts of a broken DNA POLYNUCLEOTIDE CHAIN. In this way a PHOSPHODIESTER BOND is formed between a 3'-OH group of one part of the chain and a 5'-PO4 group of the adjacent part. DNA ligase has a role in DNA replication and DNA REPAIR. It is also used in the formation of recombinant DNA molecules in GENETIC ENGINEERING.
References in periodicals archive ?
Unlike bacteria, which have a single DNA ligase, mammalian cells contain two DNA ligases: DNA ligase I functions during DNA replication, DNA ligase II during DNA repair.
The researchers do not know whether the abnormal DNA ligase is the primary defect in the disease, or a secondary effect of some other cellular problem.
First let's review what DNA ligase is and what reaction it catalyzes.