title: The molecular origin of high DNA-repair efficiency by photolyase.
abstract: The primary dynamics in photomachinery such as charge separation in photosynthesis and bond isomerization in sensory photoreceptor are typically ultrafast to accelerate functional dynamics and avoid energy dissipation. The same is also true for the DNA repair enzyme, photolyase. However, it is not known how the photoinduced step is optimized in photolyase to attain maximum efficiency. Here, we analyse the primary reaction steps of repair of ultraviolet-damaged DNA by photolyase using femtosecond spectroscopy. With systematic mutations of the amino acids involved in binding of the flavin cofactor and the cyclobutane pyrimidine dimer substrate, we report our direct deconvolution of the catalytic dynamics with three electron-transfer and two bond-breaking elementary steps and thus the fine tuning of the biological repair function for optimal efficiency. We found that the maximum repair efficiency is not enhanced by the ultrafast photoinduced process but achieved by the synergistic optimization of all steps in the complex repair reaction.
authors.affiliation: Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics, and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: Chuang
authors.initials: C
authors.lastname: Tan
authors.affiliation: Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics, and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: Zheyun
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics, and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: Jiang
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics, and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: Xunmin
authors.initials: X
authors.lastname: Guo
authors.affiliation: Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics, and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA.
authors.forename: Aziz
authors.initials: A
authors.lastname: Sancar
authors.affiliation: Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics, and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: Dongping
authors.initials: D
authors.lastname: Zhong
mesh_terms: D055162:Biocatalysis; D020134:Catalytic Domain; D004260:DNA Repair; D004255:Deoxyribodipyrimidine Photo-Lyase / Q000378:metabolism*; D009154:Mutation
chemical_list: D004255:Deoxyribodipyrimidine Photo-Lyase