Locher Kaspar P
Institut für Molekularbiologie und Biophysik, Eidgenössische Technische Hochschule Zürich, 8093 Zürich, Switzerland.
Curr Opin Struct Biol. 2004 Aug;14(4):426-31. doi: 10.1016/j.sbi.2004.06.005.
ATP-binding cassette (ABC) transporters facilitate unidirectional translocation of chemically diverse substrates across cell or organelle membranes. The recently determined crystal structures of the vitamin B(12) importer BtuCD and its cognate binding protein BtuF have revealed critical architectural features that are probably shared by other ABC transporters. For example, the arrangement of the ABC domains and their interface with the membrane-spanning domains are probably conserved, whereas the number of transmembrane helices and their arrangement are not. Two distinct mechanistic schemes for how ABC engines couple ATP hydrolysis to substrate transport have been proposed recently and are being explored.
ATP结合盒（ABC）转运蛋白促进化学性质各异的底物单向跨细胞或细胞器膜转运。最近确定的维生素B12转运体BtuCD及其同源结合蛋白BtuF的晶体结构揭示了其他ABC转运蛋白可能共有的关键结构特征。例如，ABC结构域的排列及其与跨膜结构域的界面可能是保守的，而跨膜螺旋的数量及其排列则不然。最近提出了两种关于ABC引擎如何将ATP水解与底物转运偶联的不同机制方案，目前正在进行探索。
