Weill Cornell Medical College, 1300 York Ave, New York, NY 10021, USA.
Trends Pharmacol Sci. 2010 Sep;31(9):418-26. doi: 10.1016/j.tips.2010.06.004. Epub 2010 Jul 23.
Secondary active transporters catalyze the concentrative transport of substrates across lipid membranes by harnessing the energy of electrochemical ion gradients. These transporters bind their ligands on one side of the membrane, and undergo a global conformational change to release them on the other side of the membrane. Over the last few years, crystal structures have captured several bacterial secondary transporters in different states along their transport cycle, providing insight into possible molecular mechanisms. In this review, we summarize recent findings focusing on the emerging structural and mechanistic similarities between evolutionary diverse transporters. We also discuss the structural basis of substrate binding, ion coupling and inhibition viewed from the perspective of these similarities.
次级主动转运体通过利用电化学离子梯度的能量来催化底物在脂膜中的浓缩运输。这些转运体在膜的一侧结合其配体，并经历全局构象变化将其释放到膜的另一侧。在过去的几年中，晶体结构已经捕获了几种处于不同运输循环状态的细菌次级转运体，为可能的分子机制提供了深入了解。在这篇综述中，我们总结了最近的发现，重点关注进化多样化的转运体之间新兴的结构和机制相似性。我们还从这些相似性的角度讨论了底物结合、离子偶联和抑制的结构基础。
