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结合血的富含关氨酸的RNA和DNA强烈催化氧气转移反应
Lester C-H Poon1, Stephen P Methot, William Morabi-Pazooki
1Department of Molecular Biology & Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.
Journal of the American Chemical Society
|January 27, 2011
概括
富含关氨酸的核酸与海姆复合,催化氧化反应,将氧气从过氧化转移到各种基质. 这种依赖于血红素的氧气转移对了解早期生命,疾病和开发新疗法产生影响.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 催化剂是一种催化剂.
背景情况:
- 富含关氨酸的核酸,包括RNA和DNA,形成G-四重复结构.
- 这些G-四重复结构与Fe (III) 密切结合,形成具有催化潜力的复合体.
研究的目的:
- 为了研究各种G-四复合体-血基复合体的催化活性.
- 为了确定血液中介氧化反应中的机制和氧气来源.
主要方法:
- 利用了各种富含瓜的RNA和DNAG-四重复合体,并复合了Fe(III) .
- 使用 (18) O标记的过氧化来追踪氧气的转移.
- 对基质氧化进行了动力学研究,包括哈梅特分析.
- 使用分子对接来模拟与G-四重复结构的海姆相互作用.
主要成果:
- G-四重复合体-复合体强烈催化二电子氧化硫醇,醇和烯.
- 转移到基板的氧气来源于heme的活性铁部分.
- 对 thioanisole 氧化的动力分析无法区分直接氧气转移和氧气反弹机制.
- 印氧化产生了各种产品,包括色染料.
- 结构建模表明这些 ribozymes 和 deoxyribozymes 中有一个相对开放的活性部位.
结论:
- 血结合的G-四复合体是氧气转移反应的有效催化剂.
- 这种催化能力对生命的起源,酶的设计和医学应用有广泛的影响.
- 对核酸中血红素依赖催化物的进一步研究可能会影响细胞氧化疾病和癌症治疗方法.
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