title: Single Hydrogen Bond Donation from Flavin N5 to Proximal Asparagine Ensures FAD Reduction in DNA Photolyase.
abstract: The spread of the absorbance of the stable FADH(•) radical (300-700 nm) allows CPD photolyase to highly efficiently form FADH(-), making it functional for DNA repair. In this study, FTIR spectroscopy detected a strong hydrogen bond, from FAD N5-H to the carbonyl group of the Asn378 side chain, that is modulated by the redox state of FAD. The observed characteristic frequency shifts were reproduced in quantum-mechanical models of the flavin binding site, which were then employed to elucidate redox tuning governed by Asn378. We demonstrate that enhanced hydrogen bonding of the Asn378 side chain with the FADH(•) radical increases thermodynamic stabilization of the radical state, and further ensures kinetic stabilization and accumulation of the fully reduced FADH(-) state.
authors.forename: I M Mahaputra
authors.initials: IM
authors.lastname: Wijaya
authors.affiliation: Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research , Jahnstrasse 29, Heidelberg 69120, Germany.
authors.forename: Tatiana
authors.initials: T
authors.lastname: Domratcheva
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Iwata
authors.affiliation: Department of Integrative Structural and Computational Biology and The Skaggs Institute for Chemical Biology, The Scripps Research Institute , La Jolla, California 92037, United States.
authors.forename: Elizabeth D
authors.initials: ED
authors.lastname: Getzoff
authors.forename: Hideki
authors.initials: H
authors.lastname: Kandori
mesh_terms: D001216:Asparagine / Q000737:chemistry / Q000378:metabolism*; D001665:Binding Sites; D017438:Bisphenol A-Glycidyl Methacrylate; D004260:DNA Repair; D004255:Deoxyribodipyrimidine Photo-Lyase / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology; D005182:Flavin-Adenine Dinucleotide / Q000737:chemistry / Q000378:metabolism*; D005415:Flavins / Q000378:metabolism*; D006859:Hydrogen; D006860:Hydrogen Bonding; D007700:Kinetics; D008956:Models, Chemical; D008968:Molecular Conformation; D015394:Molecular Structure; D010084:Oxidation-Reduction; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D005415:Flavins; C115612:single bond; D005182:Flavin-Adenine Dinucleotide; D017438:Bisphenol A-Glycidyl Methacrylate; D001216:Asparagine; D006859:Hydrogen; D004255:Deoxyribodipyrimidine Photo-Lyase