title: Recognition and reaction mechanisms of the (6-4) photolyase as determined by using a (6-4) photoproduct analog.
abstract: The (6-4) photoproduct, which is one of the major UV-induced DNA lesions formed at bipyrimidine sites, causes carcinogenesis at high frequency. The (6-4) photolyases restore the (6-4) photoproducts to their intact bases in a light-dependent manner, but its overall repair mechanism remains obscure. To investigate the light-dependent conversion of the (6-4) photoproduct, we prepared a (6-4) photoproduct analog with modification at 3' pyrimidone ring, in which the carbonyl group was replaced with an imine to apply to the (6-4) photolyase assay. The (6-4) photolyase shows affinity to an oligonucleotide carrying this imine analog of the (6-4) photoproduct, though the imine analog is not repaired by the (6-4) photolyase.
authors.affiliation: Division of Chemistry, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan.
authors.forename: Junpei
authors.initials: J
authors.lastname: Yamamoto
authors.forename: Kenichi
authors.initials: K
authors.lastname: Hitomi
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Hayashi
authors.forename: Elizabeth D
authors.initials: ED
authors.lastname: Getzoff
authors.forename: Shigenori
authors.initials: S
authors.lastname: Iwai
mesh_terms: D004255:Deoxyribodipyrimidine Photo-Lyase / Q000737:chemistry*; D011740:Pyrimidine Dimers / Q000737:chemistry; D013942:Thymine Nucleotides / Q000737:chemistry*
chemical_list: D011740:Pyrimidine Dimers; D013942:Thymine Nucleotides; C058406:pyrimidine-pyrimidone dimer; C098727:pyrimidine(6-4)pyrimidone photolyase; D004255:Deoxyribodipyrimidine Photo-Lyase