亚酸甲基转移酶多样性和甲基化效率的优化
1Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, Florida 33199, United States.
Environmental science & technology
|June 16, 2023
概括
酸甲基转移酶 (ArsMs) 显示了影响甲基化效率的多种结构. 在C端域和酸盐流出率调节甲基化活性.
科学领域:
- 生物化学 生物化学
- 环境科学 环境科学
- 微生物学 微生物学
背景情况:
- 酸甲基转移酶 (ArsMs) 通过使用S-adenosylmethionine (SAM) 催化甲基化.
- ArsM晶体结构显示了三个域:N端的SAM结合 (A),中心的结合 (B) 和一个C端的域 (C).
- 武器之间的结构多样性影响了它们的催化性能.
研究的目的:
- 研究ArsM的结构多样性及其对甲基化效率和基质选择性的影响.
- 确定C端域在ArsM函数中的作用.
- 探索化物流出系统与甲基化率之间的关系.
主要方法:
- 对各种武器的比较结构分析.
- 酶分析测量野生类型和截断的ArsM变体的甲基化活性.
- 与甲基化相关的化物流出率的研究.
主要成果:
- 较小的ArsM (240-300残留物) 仅具有A和B域,其甲基化活性高于具有A,B和C域的大型ArsM (320-400残留物).
- 在CrArsM中删除C终端域 (102个残留物) 与野生类型酶相比,显著增加了其As(III) 甲基化活性.
- 较低的化物流出率与较高的甲基化率相关.
结论:
- ArsM的结构变异,特别是C端域的存在和作用,是甲基化效率的关键决定因素.
- 该C端域作为ArsM催化速率的调节器.
- 甲基化速率可以通过固有的酶特性和细胞外流机制来调节.
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