title: Fluorescent postlabelling of modified DNA bases.
abstract: Postlabelling of modified DNA bases by methods other than the 32P method has attracted little attention to date. Three approaches using fluorescence have been made: (a) detection of a characteristic adduct-DNA functionality, e.g. reaction of cis-vicinal diols of PAH-DNA adducts with a boronate-containing fluorescent molecule; (b) reaction of modified nucleotides with a reactive fluorescent molecule, e.g. detection of 8-HOdG-5'-monophosphate by reaction with dansyl chloride; (c) reaction of modified DNA bases with reagents giving fluorescent products, e.g. derivatization of 7-MeGua with phenylmalondialdehyde (PhMal). Recent results in developing the latter approach are described. Reaction of a series of 7-alkylguanines, including 7-methyl-, 7-ethyl-, 7-(2-hydroxyethyl)-, 7-carboxymethyl-, 7-(2-carboxyethyl)- and 7-(2,3-dihydroxypropyl)-guanine, with PhMal gave fluorescent products showing similar spectral properties. The detection limit for fluorescence detection following reverse-phase HPLC separation was typically less than 1 pmol injected. In order to improve the sample clean-up before analysis, an antiserum has been prepared against the fluorescent derivative of 7-(2-carboxyethyl)guanine bound to carrier protein via the carboxyl group. The resulting antiserum cross-reacted with a number of PhMal derivatives.
authors.affiliation: International Agency for Research on Cancer, Unit of Environmental Carcinogens and Host Factors, Lyon, France.
authors.forename: D E
authors.initials: DE
authors.lastname: Shuker
authors.forename: M J
authors.initials: MJ
authors.lastname: Durand
authors.forename: D
authors.initials: D
authors.lastname: Molko
mesh_terms: D004247:DNA / Q000032:analysis* / Q000737:chemistry; D004249:DNA Damage; D005069:Evaluation Studies as Topic; D005456:Fluorescent Dyes; D006147:Guanine / Q000031:analogs & derivatives / Q000032:analysis / Q000737:chemistry; D009711:Nucleotides / Q000032:analysis / Q000737:chemistry; D011083:Polycyclic Compounds / Q000032:analysis / Q000737:chemistry; D013050:Spectrometry, Fluorescence
chemical_list: D005456:Fluorescent Dyes; D009711:Nucleotides; D011083:Polycyclic Compounds; D006147:Guanine; D004247:DNA