Pérez Javier, Koutsioubas Alexandros
Beamline SWING, Synchrotron SOLEIL, L'Orme des Merisiers, BP 48, Saint-Aubin, 91192 Gif-sur-Yvette, France.
Jülich Centre for Neutron Science (JCNS), Forschungszentrum Jülich GmbH, Outstation at MLZ, Lichtenbergstrasse 1, 85747 Garching, Germany.
Acta Crystallogr D Biol Crystallogr. 2015 Jan 1;71(Pt 1):86-93. doi: 10.1107/S1399004714016678.
The application of small-angle X-ray scattering (SAXS) to structural investigations of transmembrane proteins in detergent solution has been hampered by two main inherent hurdles. On the one hand, the formation of a detergent corona around the hydrophobic region of the protein strongly modifies the scattering curve of the protein. On the other hand, free micelles of detergent without a precisely known concentration coexist with the protein-detergent complex in solution, therefore adding an uncontrolled signal. To gain robust structural information on such systems from SAXS data, in previous work, advantage was taken of the online combination of size-exclusion chromatography (SEC) and SAXS, and the detergent corona around aquaporin-0, a membrane protein of known structure, could be modelled. A precise geometrical model of the corona, shaped as an elliptical torus, was determined. Here, in order to better understand the correlations between the corona model parameters and to discuss the uniqueness of the model, this work was revisited by analyzing systematic SAXS simulations over a wide range of parameters of the torus.
小角X射线散射（SAXS）应用于去污剂溶液中跨膜蛋白的结构研究受到两个主要固有障碍的阻碍。一方面，蛋白质疏水区域周围去污剂晕圈的形成强烈改变了蛋白质的散射曲线。另一方面，浓度未知的游离去污剂胶束与溶液中的蛋白质-去污剂复合物共存，因此会增加一个不受控制的信号。为了从SAXS数据中获得关于此类系统的可靠结构信息，在之前的工作中，利用了尺寸排阻色谱（SEC）和SAXS的在线联用，并且可以对已知结构的膜蛋白水通道蛋白-0周围的去污剂晕圈进行建模。确定了一个形状为椭圆环面的晕圈精确几何模型。在此，为了更好地理解晕圈模型参数之间的相关性并讨论模型的唯一性，通过分析在宽范围环面参数下的系统SAXS模拟对这项工作进行了重新审视。
