基质识别的结构基础由mitosane后修饰酶MitM在线粒素生物合成中的基质识别
Danna Dong1, Mingyu Xia2, Sili Wang2
1Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei 230026, China.
Biochemistry
|August 14, 2024
概括
MitM,Streptomyces中的一种酶,甲基化了用于抗生素和抗瘤线粒素生产的化合物. 结构分析揭示了MitM如何结合其基质和辅因子,为酶工程提供了洞察力.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 微生物学 微生物学
背景情况:
- 线粒素是Streptomyces的天然产物,具有抗菌和抗瘤的特性.
- MitM是米托米辛生物合成中的关键酶,作为N-甲基转移酶起作用.
- 之前,MitM的基质和辅因子识别的结构机制是未知的.
研究的目的:
- 阐明MitM对S-adenosyl-l-methionine (SAM) 和mitomycin A.的认可的结构基础.
- 了解MitM在线粒素生物合成期间的后线粒素修饰中的作用.
主要方法:
- 确定Apo-MitM和一个MitM-mitocin A-S-adenosylhomocysteine (SAH) 三元复合物的晶体结构.
- 蛋白质结构的分析,包括活性部位残留物和构造变化.
主要成果:
- MitM 呈现出一类I SAM-依赖的甲基转移酶折叠,并形成一个同分体.
- 形状的变化,特别是在28ALGAASLGE36循环中,有助于SAH和mitomycin A的结合.
- 在28ALGAASLGE36循环经历了显著的形状变化在线粒素A结合,从开放到关闭的活跃部位的过渡.
结论:
- 这项研究提供了关键的结构洞察力,了解MitM在线粒素生物合成中的功能.
- 这些发现为甲基转移酶酶的潜在工程提供了一个结构模板.
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