Asagoshi K, Yamada T, Terato H, Ohyama Y, Ide H
Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan.
Nucleic Acids Symp Ser. 2000(44):11-2. doi: 10.1093/nass/44.1.11.
Oxidative damage to DNA generates aberrant guanine bases such as 2,6-diamino-4-hydroxy-formamido-pyrimidine (Fapy) and 7,8-dihydro-8-oxoguanine (8-oxoG). Although synthetic oligonucleotides containing a single 8-oxoG have been widely used to study enzymatic processing of this lesion, the synthesis of oligonucleotides containing Fapy as a unique lesion has not been achieved to date. In this study, an oligonucleotide containing a single 2,6-diamino-4-hydroxy-5-(N-methyl)formamido-pyrimidine (me-Fapy, a methylated derivative of Fapy) was prepared by a DNA polymerase reaction and the subsequent alkali treatment. The repair activity of Fpg and hOGG1 proteins were compared using oligonucleotide substrates containing me-Fapy and 8-oxoG.
DNA的氧化损伤会产生异常的鸟嘌呤碱基，如2,6-二氨基-4-羟基-甲酰胺基嘧啶（Fapy）和7,8-二氢-8-氧代鸟嘌呤（8-氧代鸟嘌呤，8-oxoG）。尽管含有单个8-氧代鸟嘌呤的合成寡核苷酸已被广泛用于研究该损伤的酶促加工过程，但迄今为止尚未实现含有Fapy作为唯一损伤的寡核苷酸的合成。在本研究中，通过DNA聚合酶反应和随后的碱处理制备了含有单个2,6-二氨基-4-羟基-5-（N-甲基）甲酰胺基嘧啶（me-Fapy，Fapy的甲基化衍生物）的寡核苷酸。使用含有me-Fapy和8-氧代鸟嘌呤的寡核苷酸底物比较了Fpg和hOGG1蛋白的修复活性。
