The crystal structure of the nucleotide-free α3β3 subcomplex of F1-ATPase from the thermophilic Bacillus PS3 is a symmetric trimer
The crystal structure of the nucleotide-free α3β3 subcomplex of F1-ATPase from the thermophilic Bacillus PS3 is a symmetric trimer
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DOI：
10.1016/s0969-2126(97)00236-0
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发表时间：
1997-06
期刊：
影响因子：
5.7
通讯作者：
Y. Shirakihara;A. Leslie;J. Abrahams;J. Walker;T. Ueda;Y. Sekimoto;M. Kambara;K. Saika;Y. Kagawa;Masasuke Yoshida
中科院分区：
文献类型：
--
作者：
Y. Shirakihara;A. Leslie;J. Abrahams;J. Walker;T. Ueda;Y. Sekimoto;M. Kambara;K. Saika;Y. Kagawa;Masasuke Yoshida
背景：f1 -ATP酶是一种亚基化学计量α3β3γδ λ的寡聚体，是ATP合成酶复合物的催化组分，在细菌、叶绿体和线粒体的能量转导中起核心作用。牛线粒体f1 - atp酶的晶体结构在催化β亚基的构象和核苷酸含量上表现出明显的不对称性。F1-ATPase的α3β3亚复合物是由大肠杆菌中产生的中等嗜热杆菌ps3亚基组装而成的，该亚复合物具有活性，但不具有完整的F1-ATPase的催化协同性。该亚复合物的结构应该为f1 - atp酶的构象变异性提供新的信息，并可能为该酶所采用的不寻常的催化机制提供见解。结果：在3.2 Å分辨率下测定的无核苷酸细菌f1 - atp酶α3β3亚复合物的晶体结构表明，该低聚物具有精确的三重对称性。细菌β亚基采用与线粒体f1 - atp酶中无核苷酸β亚基基本相同的构象；α亚基在两种结构中具有相似的构象。结论：细菌f1 - atpase α和β亚基的结构与线粒体酶中的对应亚基非常相似，表明它们具有共同的催化机制。本文提出的研究允许对α和β亚基采用的不同构象进行分析，并可能最终进一步我们对这一机制的理解。
Background:F1-ATPase, an oligomeric assembly with subunit stoichiometryα3β3γδϵ, is the catalytic component of the ATP synthase complex, which plays a central role in energy transduction in bacteria, chloroplasts and mitochondria. The crystal structure of bovine mitochondrial F1-ATPase displays a marked asymmetry in the conformation and nucleotide content of the catalyticβsubunits. Theα3β3 subcomplex of F1-ATPase has been assembled from subunits of the moderately thermophilicBacillusPS3 made inEscherichia coli, and the subcomplex is active but does not show the catalytic cooperativity of intact F1-ATPase. The structure of this subcomplex should provide new information on the conformational variability of F1-ATPase and may provide insights into the unusual catalytic mechanism employed by this enzyme.Results:The crystal structure of the nucleotide-free bacterialα3β3 subcomplex of F1-ATPase, determined at 3.2 Å resolution, shows that the oligomer has exact threefold symmetry. The bacterialβsubunits adopt a conformation essentially identical to that of the nucleotide-freeβsubunit in mitochondrial F1-ATPase; theαsubunits have similar conformations in both structures.Conclusions:The structures of the bacterial F1-ATPaseαandβsubunits are very similar to their counterparts in the mitochondrial enzyme, suggesting a common catalytic mechanism. The study presented here allows an analysis of the different conformations adopted by theαandβsubunits and may ultimately further our understanding of this mechanism.