Photorepair of UV Damage to DNA: Studies with the DNA-photoreactivating Enzyme January 2, 1970 – April 31, 1973

摘要

In this report we will be concerned only with enzymatic photoreactiva-tion attributable to DNA photolyase. The only known substrates for the enzyme are cyclobutadipyrimidines in a cis-syn conformation on a DNA strand, formed by cycloaddition of the 5,6-double bond of two adjacent, light-excited pyrimidine residues. The widespread occurrence of this enzyme capable of repairing sunlight-induced damage to DNA justifies continued research efforts to uncover not only the molecular basis for its action, but also its ecological significance. The enzyme is unique in that it is the only one known that has an absolute requirement for a physical cofactor (light) to perform its catalytic function (9).