Effect of the delta subunit on assembly and proton permeability of the F0 proton channel of Escherichia coli F1F0 ATPase.
Effect of the delta subunit on assembly and proton permeability of the F0 proton channel of Escherichia coli F1F0 ATPase.
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δ亚基对大肠杆菌 F1F0 ATP 酶 F0 质子通道组装和质子通透性的影响。
DOI：
10.1128/jb.173.1.407-411.1991
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发表时间：
1991
影响因子：
3.2
通讯作者：
Brusilow,WS
中科院分区：
文献类型：
--
作者：
Angov,E;Ng,TC;Brusilow,WS
在大肠杆菌质子转位 ATP 酶组装过程中，F1 亚基与 F0 相互作用，增加跨膜质子通道的质子渗透性。我们通过从携带 F0 亚基和 delta 基因的质粒中部分和完全删除 uncH（delta 亚基）来测试 delta 亚基在此过程中的参与，并测试这些 F0 质粒对 unc+ 和 unc 突变型大肠杆菌菌株生长的影响。我们发现 delta 亚基是抑制 unc+ 细胞生长所必需的。我们还测试了从含有 F0 质粒的未删除细胞中分离出的膜的 F1 结合能力。在未删除的细胞中，这些质粒产生的 F0 数量与正常 unc+ 大肠杆菌细胞中的数量相当，而对细胞生长的影响很小。这些研究表明，δ亚基在打开 F0 质子通道中发挥着重要作用，但它并不像之前推测的那样在组装过程中充当 F0 的临时塞子（S. Pati 和 W. S. A. Brusilow, J. Biol. Chem. 264:2640-2644, 1989）。
During the assembly of the Escherichia coli proton-translocating ATPase, the subunits of F1 interact with F0 to increase the proton permeability of the transmembrane proton channel. We tested the involvement of the delta subunit in this process by partially and completely deleting uncH (delta subunit) from a plasmid carrying the genes for the F0 subunits and delta and testing the effects of those F0 plasmids on the growth of unc+ and unc mutant E. coli strains. We found that the delta subunit was required for inhibition of growth of unc+ cells. We also tested membranes isolated from unc-deleted cells containing F0 plasmids for F1-binding ability. In unc-deleted cells, these plasmids produced F0 in amounts comparable to those found in normal unc+ E. coli cells, while having only small effects on cell growth. These studies demonstrate that the delta subunit plays an important role in opening the F0 proton channel but that it does not serve as a temporary plug of F0 during assembly, as had been previously speculated (S. Pati and W. S. A. Brusilow, J. Biol. Chem. 264:2640-2644, 1989).