The role of the DELSEED motif of the β subunit in rotation of F1-ATPase
The role of the DELSEED motif of the β subunit in rotation of F1-ATPase
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DOI：
10.1074/jbc.275.19.14260
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发表时间：
2000-05-12
影响因子：
4.8
通讯作者：
Yoshida, M
中科院分区：
文献类型：
--
作者：
Hara, KY;Noji, H;Yoshida, M
F-1-ATP酶是一种旋转马达蛋白，ATP水解在γ亚基（转子轴）和α（3）β（3）亚结构（定子环）之间的界面处产生扭矩。β亚基的保守酸性“DELSEED”基序区域与γ亚基接触，并被认为参与扭矩产生。使用其中相应序列为DELSDED的嗜热α（3）β（3）γ复合物，我们用丙氨酸替换该序列中的每个残基和所有五个酸性残基。此外，γ亚基对应接触位置的两个保守残基中的每一个也被替换。令人惊讶的是，所有这些突变体都以与野生型一样多的扭矩旋转。我们的结论是，侧链的β亚基的DELSEED基序不具有直接的作用，扭矩的产生。
F-1-ATPase is a rotary motor protein, and ATP hydrolysis generates torque at the interface between the gamma subunit, a rotor shaft, and the alpha(3)beta(3) substructure, a stator ring. The region of conserved acidic "DELSEED" motif of the beta subunit has a contact with gamma subunit and has been assumed to be involved in torque generation. Using the thermophilic alpha(3)beta(3)gamma complex in which the corresponding sequence is DELSDED, we replaced each residue and all five acidic residues in this sequence with alanine. In addition, each of two conserved residues at the counterpart contact position of gamma subunit was also replaced. Surprisingly, all of these mutants rotated with as much torque as the wild-type. We conclude that side chains of the DELSEED motif of the beta subunit do not have a direct role in torque generation.