The 20 C-terminal Amino Acid Residues of the Chloroplast ATP Synthase γ Subunit Are Not Essential for Activity*
The 20 C-terminal Amino Acid Residues of the Chloroplast ATP Synthase γ Subunit Are Not Essential for Activity*
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叶绿体 ATP 合酶 γ 亚基的 20 个 C 端氨基酸残基对于活性并非必需*
DOI：
10.1074/jbc.274.20.13824
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
M. Richter
中科院分区：
文献类型：
--
作者：
M. Sokolov;Lu Lu;W. Tucker;Fei Gao;P. Gegenheimer;M. Richter
已经提出，ATP合酶的γ亚基的C末端的最后7至9个氨基酸残基在催化期间充当γ亚基相对于αβ亚基旋转的纺锤体（Abrahams，J. P.，Leslie，A. G. W.，吕特，R.，和步行者，J.E.（1994）Nature 370，621-628）。为了验证这一假设，我们选择性地从叶绿体γ亚基中删除C-末端残基，从末端的第6个残基开始，一次删除两个残基，并在末端的第20个残基结束。突变体γ基因在大肠杆菌中过表达，并与天然α3β3复合物组装。所有的γ突变体都能像野生型γ一样有效地组装起来。与野生型组装体相比，γ末端6个残基的缺失导致Ca依赖性ATP酶活性显著增加（>50%）。增加的活性持续存在，即使在删除C-末端14个残基，远远超过7个残基提出形成纺锤体。进一步的缺失导致活性降低至野生型酶在缺失所有20个C-末端残基后的活性的约19%。结果表明，γC末端的尖端对于催化作用不是必需的，并对C末端作为旋转主轴的作用提出了疑问。
It has been suggested that the last seven to nine amino acid residues at the C terminus of the γ subunit of the ATP synthase act as a spindle for rotation of the γ subunit with respect to the αβ subunits during catalysis (Abrahams, J. P., Leslie, A. G. W., Lutter, R., and Walker, J. E. (1994)Nature 370, 621–628). To test this hypothesis we selectively deleted C-terminal residues from the chloroplast γ subunit, two at a time starting at the sixth residue from the end and finishing at the 20th residue from the end. The mutant γ genes were overexpressed in Escherichia coli and assembled with a native α3β3 complex. All the mutant forms of γ assembled as effectively as the wild-type γ. Deletion of the terminal 6 residues of γ resulted in a significant increase (>50%) in the Ca-dependent ATPase activity when compared with the wild-type assembly. The increased activity persisted even after deletion of the C-terminal 14 residues, well beyond the seven residues proposed to form the spindle. Further deletions resulted in a decreased activity to ∼19% of that of the wild-type enzyme after deleting all 20 C-terminal residues. The results indicate that the tip of the γC terminus is not essential for catalysis and raise questions about the role of the C terminus as a spindle for rotation.
制备重组活性形式的ε亚基和ε亚基缺陷型叶绿体耦合因子1。
DOI：
--
发表时间：
1984
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Richter,ML;Patrie,WJ;McCarty,RE
通讯作者：
McCarty,RE
DOI：
10.1073/pnas.92.24.10964
发表时间：
1995-11-21
影响因子：
11.1
作者：
DUNCAN, TM;BULYGIN, VV;CROSS, RL
通讯作者：
CROSS, RL
叶绿体 F1 ATP 酶的活性/非活性状态转变是由 Mg2 的缓慢结合和释放诱导的。
DOI：
--
发表时间：
1990
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Guerrero,KJ;Xue,ZX;Boyer,PD
通讯作者：
Boyer,PD