Reconstitution of membrane proteolysis by FtsH
Reconstitution of membrane proteolysis by FtsH
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DOI：
10.1074/jbc.m302152200
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发表时间：
2003-05-16
影响因子：
4.8
通讯作者：
Ito, K
中科院分区：
文献类型：
--
作者：
Akiyama, Y;Ito, K
大肠杆菌FtsH是一种膜结合和ATP依赖性蛋白酶，负责降解几种膜蛋白。FtsH的作用是进行性的，并且推测涉及底物从膜到胞质溶胶的移位。虽然阐明其分子机制需要一个体外反应系统，在体外活性的这种酶对膜蛋白底物只进行了测定使用洗涤剂溶解的成分。在这里，我们报告在体外反应体系的建设FtsH催化膜蛋白降解。两个倒置的膜囊泡或两个脂蛋白体的组合，一个承载酶，另一个承载底物，通过聚乙二醇3350处理融合。然后加入ATP导致底物降解。结果表明，FtsH可以在不依赖其他细胞因子的情况下参与膜蛋白的降解过程。
Escherichia coli FtsH is a membrane-bound and ATP-dependent protease responsible for degradation of several membrane proteins. The FtsH action is processive and presumably involves dislocation of the substrate from the membrane to the cytosol. Although elucidation of its molecular mechanism requires an in vitro reaction system, in vitro activities of this enzyme against membrane protein substrates have only been assayed using detergent-solubilized components. Here we report on the construction of in vitro reaction systems for FtsH-catalyzed membrane protein degradation. A combination of two inverted membrane vesicles or of two proteoliposomes, one bearing the enzyme and the other bearing a substrate, was fused by polyethylene glycol 3350 treatment. Addition of ATP then resulted in degradation of the substrate. It was shown that FtsH can function in the process of membrane proteins degradation without aid from any other cellular factors.