影响通道的子毒素表现出双 cis-trans 异构体
Konstantin S Mineev1, Mikhail A Chernykh1, Vladislav V Motov1,2
1Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.
FEBS letters
|July 28, 2023
概括
子α-毒素 (alpha-NaTx) 是阻断通道的小蛋白质. 这项研究表明,由于独特的键配置,Lqq4毒素采用多种结构,扩大了已知的α-毒素的构造空间.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 药理学 药理学是指药理学的学科.
背景情况:
- 子α-毒素 (α-NaTx) 是已知可以抑制电压关闭通道 (Nav) 的小蛋白质.
- 之前的研究强调了和利基模式在Nav结合的α-NaTx特异性中的作用.
- 了解α-NaTx结构-功能关系对于开发通道调制器至关重要.
研究的目的:
- 为了确定来自子毒的*Leiurus quinquestriatus*Lqq4毒素的溶液结构.
- 调查Lqq4.4观察到的功能性质的结构基础.
- 探索α-NaTx家族内部的结构多样性.
主要方法:
- 核磁共振 (NMR) 光谱法用于溶液结构的确定.
- 对键配置的分析 (cis-trans异构体).
- 对α-NaTx. 的比较结构分析.
主要成果:
- Lqq4毒素表现出一组长期存在的,结构上不同的状态.
- 这些不同的状态归因于两个键 (V56-P57和C17-G18) 的替代 cis-trans 配置.
- 鉴定的cis异构体代表了以前在α-NaTx中未观察到的新型配置.
结论:
- 子α-毒素的结构格局比以前认可的要广泛得多.
- 在Lqq4中发现了替代性键配置,这挑战了α-NaTx的现有结构范式.
- 这一发现对理解毒素通道相互作用和设计新型通道调节器具有重要意义.
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