在酸盐/酸盐ABC载体中转抑制的结构基础
Sabina Gerber1, Mireia Comellas-Bigler, Birke A Goetz
1Institute of Molecular Biology and Biophysics, ETH Zürich, HPK D14.3, 8093 Zürich, Switzerland.
概括
研究人员揭示了膜载体中转抑制的结构基础. 聚酸盐/酸盐与ABC输送器 (ModBC) 结合,将其锁定在向内面的状态中,防止基质运输.
科学领域:
- 生物化学 生化学
- 结构生物学 结构生物学
- 分子生物学分子生物学
背景情况:
- 膜运输蛋白对细胞功能至关重要.
- 转载抑制,即基质抑制载体周转,缺乏明确的结构理解.
研究的目的:
- 为了阐明在酸盐/酸盐ABC输送器中转抑制的结构基础.
- 了解基质结合如何影响传送器构造和活动.
主要方法:
- 使用X射线结晶学来确定ModBC传送器的结构.
- 在转抑制状态下分析晶体结构.
主要成果:
- 确定了Methanosarcina acetivorans ModBC载体在转抑制状态中的晶体结构.
- 在核酸结合子单元中的调节域的接口上发现了氧离子结合口.
- 酸盐或酸盐结合阻止了ATPase的活性,并将载体锁定在面向内部的形状中.
结论:
- 基质结合 (molybdate/tungstate) 诱导一个全效应,抑制ATPase活性.
- 这种抑制阻止了传送器在向内和向外的状态之间交替,从而阻断了传输.
- 这项研究提供了ABC载体中转抑制的结构机制.
相关概念视频
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