合基板和离子结合到依赖的阿斯巴酸输送器的细胞外门
Olga Boudker1, Renae M Ryan, Dinesh Yernool
1Department of Biochemistry and Molecular Biophysics, Columbia University, 650 West 168th Street, New York, New York 10032, USA.
Nature
|January 19, 2007
概括
研究人员研究了Glt(Ph) 亚斯巴酸转运体,揭示了它如何利用离子将分子移动穿过细胞膜. 螺旋式发针2作为门,控制基板和离子接入,以实现高效的运输.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 膜运输 运输 膜运输
背景情况:
- 二次载体是关键的不可分割的膜蛋白.
- 它们通过对离子梯度的合运输来促进度基质的吸收.
- 了解它们的机制是细胞生理学的关键.
研究的目的:
- 阐明与 (Na+) 合的阿斯巴酸转运体Glt的结构和热力学机制.
- 为了确定阿斯巴达酸盐,离子和抑制剂的特定结合点.
- 描述螺旋式发针2在控制基板和离子接入中的作用.
主要方法:
- 结晶学研究以确定Glt的3D结构.
- 热力学分析以了解结合亲和和和能量学.
- 与其他联运输体 (如LeuT) 的结构比较.
主要成果:
- 确定了阿斯巴甜酸,两个离子和抑制剂d,l-threo-beta-benzyloxyaspartate的结合点.
- 识别了螺旋式发针2作为控制进入内部结合点的细胞外门.
- 证明至少有两个离子在基质附近结合,与LeuT.形成基因.
结论:
- 解卷的α螺旋作为合运输器中的保存离子结合动图.
- 这种图案促进了结合和构造变化,这对于运输周期至关重要.
- 螺旋式发针2在调节基板和离子透方面发挥着至关重要的作用.
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