For the extraction of the best possible X-ray diffraction data from macromolecular crystals, accurate positioning of the crystals with respect to the X-ray beam is crucial. In addition, information about the shape and internal defects of crystals allows the optimization of data-collection strategies. Here, it is demonstrated that the X-ray beam available on the macromolecular crystallography beamline P14 at the high-brilliance synchrotron-radiation source PETRA III at DESY, Hamburg, Germany can be used for high-energy phase-contrast microtomography of protein crystals mounted in an optically opaque lipidic cubic phase matrix. Three-dimensional tomograms have been obtained at X-ray doses that are substantially smaller and on time scales that are substantially shorter than those used for diffraction-scanning approaches that display protein crystals at micrometre resolution. Adding a compound refractive lens as an objective to the imaging setup, two-dimensional imaging at sub-micrometre resolution has been achieved. All experiments were performed on a standard macromolecular crystallography beamline and are compatible with standard diffraction data-collection workflows and apparatus. Phase-contrast X-ray imaging of macromolecular crystals could find wide application at existing and upcoming low-emittance synchrotron-radiation sources.

中文翻译：

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通过高能相差X射线成像可视化蛋白质晶体。

为了从大分子晶体中提取最佳的X射线衍射数据，精确地将晶体相对于X射线束定位至关重要。此外，有关晶体形状和内部缺陷的信息可以优化数据收集策略。在此证明，德国汉堡DESY的高亮度同步辐射源PETRA III的大分子晶体学束线P14上可用的X射线束可用于已安装蛋白晶体的高能相差显微断层照相术在不透光的脂质立方相基质中。在X射线剂量下获得的三维断层图要小得多，并且在时间尺度上要比用于以微米分辨率显示蛋白质晶体的衍射扫描方法短得多。将复合折射透镜作为成像设置的目标，已实现了亚微米分辨率的二维成像。所有实验均在标准大分子晶体学束线上进行，并且与标准衍射数据收集工作流程和设备兼容。大分子晶体的相衬X射线成像可以在现有和即将出现的低辐射同步辐射源中得到广泛应用。已经实现了亚微米分辨率的二维成像。所有实验均在标准大分子晶体学束线上进行，并且与标准衍射数据收集工作流程和设备兼容。大分子晶体的相衬X射线成像可以在现有和即将出现的低辐射同步辐射源中得到广泛应用。已经实现了亚微米分辨率的二维成像。所有实验均在标准大分子晶体学束线上进行，并且与标准衍射数据收集工作流程和设备兼容。大分子晶体的相衬X射线成像可以在现有和即将出现的低辐射同步辐射源中得到广泛应用。