NanoBio Lab, 31 Biopolis Way, The Nanos, Singapore, 138669, Singapore.
Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, 117585, Singapore.
Angew Chem Int Ed Engl. 2019 Jun 11;58(24):8034-8038. doi: 10.1002/anie.201901833. Epub 2019 May 8.
Ions are transported across membrane mostly via carrier or channel mechanisms. Herein, a unique class of molecular-machine-inspired membrane transporters, termed molecular swings is reported that utilize a previously unexplored swing mechanism for promoting ion transport in a highly efficient manner. In particular, the molecular swing, which carries a 15-crown-5 unit as the ion-binding and transporting unit, exhibits extremely high ion-transport activities with EC values of 46 nm (a channel:lipid molar ratio of 1:4800 or 0.021 mol % relative to lipid) and 110 nm for K and Na ions, respectively. Remarkably, such ion transport activities remain high in a cholesterol-rich environment, with EC values of 130 (0.045 mol % relative to lipid/cholesterol) and 326 nm for K and Na ions, respectively.
离子主要通过载体或通道机制跨膜运输。本文报道了一类独特的分子机器启发的膜转运蛋白，称为分子秋千，它利用以前未被探索的摆动机制以高效促进离子运输。具体而言，分子秋千带有 15-冠-5 单元作为离子结合和运输单元，表现出极高的离子转运活性，对于 K 和 Na 离子的 EC 值分别为 46 nm（通道：脂质摩尔比为 1:4800 或相对于脂质为 0.021 mol％）和 110 nm。值得注意的是，在富含胆固醇的环境中，这种离子转运活性仍然很高，对于 K 和 Na 离子的 EC 值分别为 130（相对于脂质/胆固醇为 0.045 mol％）和 326 nm。
