title: Paradoxical hotspots for guanine oxidation by a chemical mediator of inflammation.
abstract: Guanine in DNA is a major oxidation target owing to its low ionization potential (IP), and there is often an inverse correlation between damage frequency and sequence-dependent variation in guanine IP. We report that the biological oxidant nitrosoperoxycarbonate (ONOOCO2(-)) paradoxically selects guanines with the highest IP in GC-containing contexts. Along with sequence-dependent variation in damage chemistry, this behavior points to factors other than charge migration as determinants of genomic DNA oxidation.
authors.affiliation: Biological Engineering Division, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Yelena
authors.initials: Y
authors.lastname: Margolin
authors.forename: Jean-Francois
authors.initials: JF
authors.lastname: Cloutier
authors.forename: Vladimir
authors.initials: V
authors.lastname: Shafirovich
authors.forename: Nicholas E
authors.initials: NE
authors.lastname: Geacintov
authors.forename: Peter C
authors.initials: PC
authors.lastname: Dedon
mesh_terms: D001483:Base Sequence; D002460:Cell Line; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D006147:Guanine / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D018836:Inflammation Mediators / Q000737:chemistry / Q000494:pharmacology*; D007477:Ions / Q000737:chemistry; D016877:Oxidants / Q000737:chemistry / Q000378:metabolism; D010084:Oxidation-Reduction / Q000187:drug effects; D010777:Photochemistry; D012256:Riboflavin / Q000737:chemistry / Q000494:pharmacology
chemical_list: D018836:Inflammation Mediators; D007477:Ions; D016877:Oxidants; D006147:Guanine; D004247:DNA; D012256:Riboflavin