The X-ray Structure determination of Alkylated DNA Base Excision Repair Enzymes

烷基化DNA碱基切除修复酶的X射线结构测定

• 批准号: 05671781
• 负责人: YAMAGATA Yuriko
• 金额: $ 1.34万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05671781/
• 关键词: DNA Repair Enzyme; 3-Methyladenine-DNA Glycosylase; Three-dimensional Structure

Escherichia coli has two DNA repair enzymes that liberate 3-methyladenine from DNA damaged by carcinogenic and/or mutagenic alkylating agents, namely 3-methyladenine-DNA Glycosylases I and II.They are distinguishable by their molecular sizes, enzymic properties and responses to alkylating agents. An adaptive DNA repair enzyme, 3-methyladenine-DNA glycosylase II,catalyzes the release of several alkylated bases in addition to 3-methyladenine. We have determined the three-dimensional structure of 3-methyladenine-DNA glycosylase II at a 2.3* resolution. The enzyme consists of three domains, one alpha+beta fold domain and two all alpha-helical domains. The comparison of amino acid sequence with those of Bacillus subtilis and Saccharomyces cerevisiae 3-methyladenine-DNA glycosylases and mutagenic studies allow to propose that the active site is located in a cleft between domains II and III.On the other hand, a constitutive enzyme 3-methyladenine-DNA glycosylase I releases only 3-methyladenine. The crystallization of 3-methyladenine-DNA glycosylase I is in progress.

大肠杆菌有两种 DNA 修复酶，即 3-甲基腺嘌呤-DNA 糖基化酶 I 和 II，可以从被致癌和/或诱变烷化剂损坏的 DNA 中释放出 3-甲基腺嘌呤。它们的区别在于分子大小、酶性质和对烷化剂的反应。 3-甲基腺嘌呤-DNA 糖基化酶 II 是一种适应性 DNA 修复酶，可催化除 3-甲基腺嘌呤外的几种烷基化碱基的释放。我们以 2.3* 分辨率确定了 3-甲基腺嘌呤-DNA 糖基化酶 II 的三维结构。该酶由三个结构域组成，一个 α+β 折叠结构域和两个全 α-螺旋结构域。通过与枯草芽孢杆菌和酿酒酵母 3-甲基腺嘌呤-DNA 糖基化酶的氨基酸序列比较以及诱变研究，可以推测活性位点位于结构域 II 和 III 之间的缝隙中。 另一方面，组成型酶 3-甲基腺嘌呤-DNA 糖基化酶 I 仅释放 3-甲基腺嘌呤。 3-甲基腺嘌呤-DNA 糖基化酶 I 的结晶正在进行中。

项目成果

I.Terashima et al.: "Demethylation of O^6-Methylguanine in DNA by O^6-Methylguanine-DNA Methyltransferase:Synthesis and Chracterization of O^6,9-Dimethylguanine that is Coordinated with eis-Platin at N7-Position" Chem.Pharm.Bull.(in press). (1994)

I.Terashima 等人：“O^6-甲基鸟嘌呤-DNA 甲基转移酶对 DNA 中的 O^6-甲基鸟嘌呤进行去甲基化：在 N7 位与 eis-Platin 协调的 O^6,9-二甲基鸟嘌呤的合成和表征”

Y.Yamagata: "Conformation of 3-Substituted Purine Nucleoside Studied by X-Ray Crystallography and Theoretical Calculations" Nucleosides and Nucleotides. 13. 1327-1335 (1994)

Y.Yamagata：“通过X射线晶体学和理论计算研究3-取代嘌呤核苷的构象”核苷和核苷酸。

S.Asano: "Reaction of 9-Substituted 1-Aminoadenines with Nucleophiles and Syntheses of 3-Substituted 3H-Imidazo [4,5-e][1,2,4]triazolo[1,5-c][1,2,3]triazines" Nucleosides & Nucleotides. 13. 1453-1465 (1994)

S.Asano：“9-取代的 1-氨基腺嘌呤与亲核试剂的反应以及 3-取代的 3H-咪唑并[4,5-e][1,2,4]三唑并[1,5-c][1,2”的合成

Y.Yamagata: "Conformation of 3-Substituted Purine Nucleoside by X-ray Crystallography and Theoretical Calculations" Nucleosides & Nucleotides. 13. 1327-1335 (1994)

Y.Yamagata：“通过 X 射线晶体学和理论计算确定 3-取代嘌呤核苷的构象”

Masae Yamaki: "Blespirol, A Phenanthrene with A Spirolactone Ring from Bletilla striata" Phytochem.33. 1497-1498 (1993)

Masae Yamaki：“Blespirol，一种带有来自白芨的螺内酯环的菲”Phytochem.33。