title: The enzymatic release of O6-methylguanine and 3-methyladenine from DNA reacted with the carcinogen N-methyl-N-nitrosourea.
abstract: Endonuclease II (deoxyribonucleate oligonucleotidohydrolase, EC 3.1.4.30) of Escherichia coli has been shown to break phosphodiester bonds in alkylated DNA and depurinated DNA. The hypothesis that depurination is a step in the mechanism of the reaction with alkylated DNA is supported by in vitro experiments with DNA reacted with N-methyl-N-nitrosourea. Endonuclease II releases O(6)-methylguanine and 3-methyladenine, but not 7-methylguanine, from DNA that has been methylated by the carcinogen N-methyl-N-nitrosourea.
mesh_terms: D000225:Adenine; D002384:Catalysis; D055598:Chemical Phenomena; D002621:Chemistry; D002845:Chromatography; D002854:Chromatography, Paper; D002855:Chromatography, Thin Layer; D004269:DNA, Bacterial; D003851:Deoxyribonucleases; D004720:Endonucleases; D004926:Escherichia coli / Q000032:analysis; D006147:Guanine; D009607:Nitrosourea Compounds; D013431:Sulfates
chemical_list: D004269:DNA, Bacterial; D009607:Nitrosourea Compounds; D013431:Sulfates; D006147:Guanine; D003851:Deoxyribonucleases; D004720:Endonucleases; D000225:Adenine