title: Phage nucleoprotein-psoralen interaction: quantitative characterization of dark and photoreactions.
abstract: The irradiation of the phage T7 system containing psoralen as photosensitizer causes many processes, each of them leading to phage inactivation. These processes include the UV-induced photoreactions in the phage nucleic acid, and photoreactions in the nucleic acid sensitized by either psoralen or psoralen photobreakdown products. In addition the intercalation of the psoralen molecule itself in the phage nucleic acid as well as the psoralen photobreakdown products cause phage inactivation. Under appropriate experimental conditions these reactions can be studied and characterized separately. The quantitative characteristics (e.g. inactivation cross-section, action spectra and index for dark genotoxicity) are demonstrated for different linear and angular psoralens. Some theoretical and practical consequences of the results obtained are discussed.
authors.affiliation: Institute of Biophysics, Semmelweis University of Medicine, Budapest, Hungary.
authors.forename: G
authors.initials: G
authors.lastname: Rontó
authors.forename: K
authors.initials: K
authors.lastname: Tóth
authors.forename: S
authors.initials: S
authors.lastname: Gáspár
authors.forename: G
authors.initials: G
authors.lastname: Csik
mesh_terms: D003624:Darkness; D004926:Escherichia coli / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D011564:Furocoumarins / Q000378:metabolism / Q000494:pharmacology*; D008027:Light; D009698:Nucleoproteins / Q000378:metabolism* / Q000528:radiation effects; D013604:T-Phages / Q000187:drug effects* / Q000502:physiology / Q000528:radiation effects; D014466:Ultraviolet Rays
chemical_list: D011564:Furocoumarins; D009698:Nucleoproteins