title: Tris buffer protects DNA backbone against breakage upon irradiation with ultraviolet light.
abstract: We show that Tris molecules protect DNA against nicking upon irradiation with ultraviolet light. However, the protective effect only concerns DNA backbone but not bases and it is observed in aqueous solution but not in formamide. Changes of pH or ionic strength due to Tris have no effect on the protection. The present observation has a practical importance for photofootprinting studies of DNA and its complexes with proteins but it can also serve as a basis for a development of a novel method reflecting DNA hydration and conformation.
authors.affiliation: Institute of Biophysics, Czech Academy of Sciences, Brno.
authors.forename: E
authors.initials: E
authors.lastname: Kejnovský
authors.forename: J
authors.initials: J
authors.lastname: Kypr
mesh_terms: D010582:Bacteriophage lambda; D004247:DNA / Q000187:drug effects / Q000528:radiation effects*; D004249:DNA Damage / Q000187:drug effects*; D004271:DNA, Fungal / Q000187:drug effects / Q000302:isolation & purification / Q000528:radiation effects; D004279:DNA, Viral / Q000187:drug effects / Q000302:isolation & purification / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D004587:Electrophoresis, Agar Gel; D004926:Escherichia coli; D014325:Tromethamine / Q000494:pharmacology*; D014466:Ultraviolet Rays
chemical_list: D004271:DNA, Fungal; D004279:DNA, Viral; D014325:Tromethamine; D004247:DNA