Membrane insertion of F0 c subunit of F0F1 ATPase depends on glycolipozyme MPIase and is stimulated by YidC
Membrane insertion of F0 c subunit of F0F1 ATPase depends on glycolipozyme MPIase and is stimulated by YidC
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DOI：
10.1016/j.bbrc.2017.04.095
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发表时间：
2017-05-27
影响因子：
3.1
通讯作者：
Nishiyama, Ken-ichi
中科院分区：
文献类型：
--
作者：
Nishikawa, Hanako;Sasaki, Masaru;Nishiyama, Ken-ichi
F0F1 ATPase的F-0 c亚基(F-0-c)有两个跨膜延伸，N-端和C-端暴露在大肠杆菌细胞膜的周质(胞外)侧。尽管在体外已有广泛的用酶保护法分析F-0-c插入，但由于膜保护片段(膜插入的一个指标)是F-0-c的全长多肽，与无膜插入的抗酶构象相同，目前尚不清楚这种分析是否能忠实地阐明插入过程。我们发现，通过在酶消化中加入辛基葡萄糖苷可以区分抗酶构象和膜插入构象。通过这个系统，我们发现F-0-c插入依赖于参与膜插入的糖基酶MPlase，并受到YidC的刺激。此外，我们还发现，酸性磷脂PG和CL将F-0-c转化为抗蛋白酶的形式，而MPIase阻止了这种抗酶构象的获得。(C)2017 Elsevier Inc.保留所有权利。
The F-0 c subunit of F0F1 ATPase (F-0-c) possesses two membrane-spanning stretches with N- and C-termini exposed to the periplasmic (extracellular) side of the cytoplasmic membrane of E. coli. Although F-0-c insertion has been extensively analyzed in vitro by means of protease protection assaying, it is unclear whether such assays allow elucidation of the insertion process faithfully, since the membrane protected fragment, an index of membrane insertion, is a full-length polypeptide of F-0-c, which is the same as the protease-resistant conformation without membrane insertion. We found that the protease-resistant conformation could be discriminated from membrane-insertion by including octyl glucoside on protease digestion. By means of this system, we found that F-0-c insertion depends on MPlase, a glycolipozyme involved in membrane insertion, and is stimulated by YidC. In addition, we found that acidic phospholipids PG and CL transform F-0-c into a protease-resistant form, while MPIase prevents the acquisition of such a protease-resistant conformation. (C) 2017 Elsevier Inc. All rights reserved.