title: Mechanisms of chemical mutagenesis and carcinogenesis: effects on DNA replication of methylation at the O6-guanine position of dGTP.
abstract: The incorporation of O6-methyl-dGTP during DNA replication in vitro by 'Klenow' E. coli pol I was determined. O6-Methyl-dGTP was found to: (i) incorporate opposite T and C template residues, with a greater than 20-fold preference for T, and (ii) arrest DNA synthesis when incorporated in place of dATP at all but pyrimidine-rich growing-strand sequences. The significance of O6-methyl-dGTP incorporation during DNA biosynthesis in vivo for mutagenesis and carcinogenesis is discussed.
mesh_terms: D001482:Base Composition; D001483:Base Sequence; D002471:Cell Transformation, Neoplastic; D004256:DNA Polymerase I / Q000378:metabolism; D004261:DNA Replication; D003848:Deoxyguanine Nucleotides / Q000302:isolation & purification / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology; D009154:Mutation; D010957:Plasmids; D013698:Templates, Genetic
chemical_list: D003848:Deoxyguanine Nucleotides; C023827:O(6)-methyldeoxyguanosine triphosphate; C029603:deoxyguanosine triphosphate; D004256:DNA Polymerase I