Do DNA repair enzymes work?
DNA repair enzymes are enzymes that recognize and correct physical damage in DNA, caused by exposure to radiation, UV light or reactive oxygen species. The correction of DNA damage alleviates loss of genetic information, generation of double-strand breaks, and DNA crosslinkages.
What is the function of photolyase?
Photolyases (EC 4.1. 99.3) are DNA repair enzymes that repair damage caused by exposure to ultraviolet light. These enzymes require visible light (from the violet/blue end of the spectrum) both for their own activation and for the actual DNA repair.
What enzyme helps repair DNA?
DNA ligase, shown above repairing chromosomal damage, is an enzyme that joins broken nucleotides together by catalyzing the formation of an internucleotide ester bond between the phosphate backbone and the deoxyribose nucleotides.
Do eukaryotes have Photolyase?
The CPD class II photolyases are ubiquitous in archaea and eukaryotes but rare in bacteria (found only in Methanomicrobia and Methanobacteria) and lost in placental mammals.
How photoreactivation can help repair a damaged DNA?
Photoreactivation is a DNA repair pathway present in all organisms apart from placental mammals(Kanai et al., 1997). During photoreactivation, the enzyme photolyase uses visible light (violet/blue) as a source of energy (ATP independent) to repair UV-induced DNA damage in the form of CPDs or (6-4)PPs.