Conformational switching by the scaffolding protein D directs the assembly of bacteriophage phiX174.
Conformational switching by the scaffolding protein D directs the assembly of bacteriophage phiX174.
复制标题
支架蛋白 D 的构象转换指导噬菌体 phiX174 的组装。
DOI：
10.1016/j.molcel.2004.08.023
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发表时间：
2004
期刊：
影响因子：
16
通讯作者：
Rossmann,MichaelG
中科院分区：
文献类型：
--
作者：
Morais,MarcC;Fisher,Megan;Kanamaru,Shuji;Przybyla,Laralynne;Burgner,John;Fane,BentleyA;Rossmann,MichaelG
噬菌体φX174外部支架蛋白D在与其他结构蛋白相互作用之前的三维结构已通过X射线晶体学测定为3.3 μ m。晶体属于空间群P41212，在不对称单元中有一个二聚体，非常类似于在φX174前衣壳结构中观察到的不对称二聚体。此外，应用晶体学41对称操作这些二聚体之一产生四聚体类似的四聚体在二十面体不对称单位的原衣壳。这些数据表明，D蛋白的二聚体和四聚体是真正的形态发生中间体，可以独立于其他蛋白质参与原衣壳形态发生。因此，D支架蛋白的晶体结构代表了多肽在原衣壳组装之前的状态。因此，与原衣壳结构的比较提供了一个难得的机会，以遵循复杂的大分子组装体的建设所必需的构象转换事件。
The three-dimensional structure of bacteriophage φX174 external scaffolding protein D, prior to its interaction with other structural proteins, has been determined to 3.3 Å by X-ray crystallography. The crystals belong to space group P41212 with a dimer in the asymmetric unit that closely resembles asymmetric dimers observed in the φX174 procapsid structure. Furthermore, application of the crystallographic 41symmetry operation to one of these dimers generates a tetramer similar to the tetramer in the icosahedral asymmetric unit of the procapsid. These data suggest that both dimers and tetramers of the D protein are true morphogenetic intermediates and can form independently of other proteins involved in procapsid morphogenesis. The crystal structure of the D scaffolding protein thus represents the state of the polypeptide prior to procapsid assembly. Hence, comparison with the procapsid structure provides a rare opportunity to follow the conformational switching events necessary for the construction of complex macromolecular assemblies.