细菌ECF载体S组件的结构和机制
Peng Zhang1, Jiawei Wang, Yigong Shi
1Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Princeton, New Jersey 08544, USA.
Nature
|October 26, 2010
概括
研究人员确定了RIBU的结构,RIBU是能量合因子 (ECF) 载体中的关键蛋白质,揭示了其 рибофлавин结合部位和 prokaryotes 中必需维生素吸收的潜在运输机制.
科学领域:
- 膜运输蛋白质 膜运输蛋白质
- 结构生物学是结构生物学.
- Prokaryotic 细胞生物学 细胞生物学
背景情况:
- 能量合因子 (ECF) 载体促进 prokaryotes 中的必需维生素吸收.
- ECF传递器由基质结合 (S),ATP结合 (A,A') 和跨膜 (T) 组件组成.
- 对于ECF传送器的结构基础和运输机制,基本上是未知的.
研究的目的:
- 为了阐明ECF类型利博弗拉输送器的S组件的结构.
- 为了确定 рибофлавин 的结合部位和潜在的运输途径.
- 为了深入了解更广泛的ECF传送器家族的结构和功能.
主要方法:
- 使用X射线晶体学来确定来自Staphylococcus aureus的RIBU (S成分) 的结构.
- 使用结构分析和序列对齐来识别关键特征和保存元素.
主要成果:
- 在3.6-Å分辨率下确定了RIBU的晶体结构,揭示了一种新的传送折叠.
- 里布U含有六个跨膜段,并在其周等离子体区域结合一个利博胺分子.
- 确定了必不可少的带结合残留物和一个假定的传输路径.
结论:
- 确定的结构为ECF传送器的S组件提供了第一个原子层次的视图.
- 结构性洞察力表明, riboflavin 结合和运输的机制.
- 保存的特征表明ECF传送器家族中的潜在共同点.
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