title: Investigation of real-time photorepair activity on DNA via surface plasmon resonance.
abstract: The cyclobutane pyrimidine dimer (CPD) and 6-4 lesion formations along with the specific breaks on strands are the most common type of DNA damage caused by Ultraviolet light (UV) irradiation. CPD photolyase I and II construct two subfamilies of flavoproteins, which have recognition and repair capabilities of CPD sites on both single stranded (ssDNA) and double stranded DNA (dsDNA) with the aid of blue light energy. The other types of flavoprotein family consist of cryptochromes (CRY) that act as photoreceptors in plants, or circadian rhythm regulators in animals. Recent findings showed that a specific type of Cryptochrome-Drosophila, Arabidopsis, Synechocystis, Human (CRY-DASH) has photorepair activity on ssDNA. In this work, real-time interactions between CRY-DASH and ss/dsDNA as well as the interactions between Vibrio cholerae photolyase (VcPHR) and ss/dsDNA were investigated using Surface Plasmon Resonance (SPR). The interactions were then characterized and compared in order to investigate the effect of different types of flavoprotein on UV damaged ss/dsDNA. SPR results confirm the specific binding of VcPHR and CRY-DASH with UV treated DNA. This study is the first instance to quantify the interactions of UV treated and untreated DNA with flavoproteins.
authors.affiliation: Chemical and Biological Engineering, Koc University, Sariyer, Istanbul, Turkey. rkizilel@ku.edu.tr
authors.forename: Rıza
authors.initials: R
authors.lastname: Kizilel
authors.forename: Enis
authors.initials: E
authors.lastname: Demir
authors.forename: Selimcan
authors.initials: S
authors.lastname: Azizoglu
authors.forename: Hande
authors.initials: H
authors.lastname: Asimgil
authors.forename: Hande
authors.initials: H
authors.lastname: Asımgi
authors.forename: Ibrahim Halil
authors.initials: IH
authors.lastname: Kavakli
authors.forename: Seda
authors.initials: S
authors.lastname: Kizilel
mesh_terms: D000042:Absorption; D000818:Animals; D003199:Computer Systems; D056931:Cryptochromes / Q000302:isolation & purification; D004247:DNA / Q000528:radiation effects*; D004249:DNA Damage; D004260:DNA Repair / Q000528:radiation effects*; D004277:DNA, Single-Stranded; D004255:Deoxyribodipyrimidine Photo-Lyase / Q000302:isolation & purification / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007700:Kinetics; D011485:Protein Binding / Q000528:radiation effects; D013057:Spectrum Analysis; D020349:Surface Plasmon Resonance / Q000379:methods*; D014466:Ultraviolet Rays; D014734:Vibrio cholerae / Q000201:enzymology
chemical_list: D056931:Cryptochromes; D004277:DNA, Single-Stranded; D004247:DNA; D004255:Deoxyribodipyrimidine Photo-Lyase