MANUEL MAESTRE-REYNAYamamoto JHuang W.-CTsai M.-DEssen L.-OBessho Y.2022-11-112022-11-11201820522525https://www.scopus.com/inward/record.uri?eid=2-s2.0-85053118539&doi=10.1107%2fS205225251800996X&partnerID=40&md5=a8c6bf886961f33c2d67643014b5d353https://scholars.lib.ntu.edu.tw/handle/123456789/624873Cyclobutane pyrimidine dimer (CPD) photolyases harness the energy of blue light to repair UV-induced DNA CPDs. Upon binding, CPD photolyases cause the photodamage to flip out of the duplex DNA and into the catalytic site of the enzyme. This process, called base-flipping, induces a kink in the DNA, as well as an unpaired bubble, which are stabilized by a network of protein-nucleic acid interactions. Previously, several co-crystal structures have been reported in which the binding mode of CPD photolyases has been studied in detail. However, in all cases the internucleoside linkage of the photodamage site was a chemically synthesized formacetal analogue and not the natural phosphodiester. Here, the first crystal structure and conformational analysis via molecular-dynamics simulations of a class II CPD photolyase in complex with photodamaged DNA that contains a natural cyclobutane pyrimidine dimer with an intra-lesion phosphodiester linkage are presented. It is concluded that a highly conserved bubble-intruding region (BIR) mediates stabilization of the open form of CPD DNA when complexed with class II CPD photolyases. © 2018 International Union of Crystallography. All rights reserved.Class II CPD photolyases; Crystal structure; Cyclobutane pyrimidine dimer; DNA distortion; DNA repairjournal article10.1107/S205225251800996X2-s2.0-85053118539