一个真核生物酸盐转运器的晶体结构
Bjørn P Pedersen1, Hemant Kumar, Andrew B Waight
1Department of Biochemistry and Biophysics, University of California, San Francisco, California 94158, USA.
Nature
|April 2, 2013
概括
研究人员揭示了真菌酸盐输送器 (PiPT) 的结构,揭示了它对营养吸收的机制. 这一发现提供了关于细胞如何运输必需酸盐的见解,并与癌症等疾病中涉及的人类转运器有关.
科学领域:
- 结构生物学是结构生物学.
- 生物化学 生物化学
- 分子生物学分子生物学
背景情况:
- 酸盐对于细胞功能至关重要,包括能量储存和合成.
- 质子结合运输体,如主要促进体超级家族 (MFS),是生物体酸盐吸收和感应的关键.
- 了解这些载体对于各种生物过程和疾病研究至关重要.
研究的目的:
- 为了确定真菌高亲和酸盐输送器PiPT的高分辨率结构.
- 为了阐明PiPT的运输机制和基质结合部位.
- 为相关的人类载体家族 (SLC22) 提供结构性见解.
主要方法:
- 使用X射线结晶学来确定PiPT的2.9 Å结构.
- 分析了结构,以确定质子和酸盐通路和结合点.
- 采用同质模型来研究相关的人类SLC22载体.
主要成果:
- PiPT的结构被分解为面向内部的封闭状态,揭示了结合酸盐.
- 观察到明显的质子和酸盐退出途径的证据.
- 为PiPT运输提出了一个修改的不对称的"摇摆开关"机制.
- SLC22传送器的结构模型表明了基质结合和电荷选择性原理.
结论:
- PiPT结构提供了对高亲和酸盐运输的详细分子理解.
- 这些发现揭示了MFS运输器的运输机制和酸盐吸收.
- 这项研究为了解与癌症药物耐药性相关的人类SLC22载体提供了结构基础.
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