European Molecular Biology Laboratory, 6 Rue Jules Horowitz, BP 181, 38042 Grenoble, Cedex 9, France.
J Struct Biol. 2011 Aug;175(2):236-43. doi: 10.1016/j.jsb.2011.03.002. Epub 2011 Mar 6.
The increase in the number of large multi-component complexes and membrane protein crystal structures determined over the last few years can be ascribed to a number of factors such as better protein expression and purification systems, the emergence of high-throughput crystallization techniques and the advent of 3rd generation synchrotron sources. However, many systems tend to produce crystals that can be extremely heterogeneous in their diffraction properties. This prevents, in many cases, the collection of diffraction data of sufficient quality to yield useful biological or phase information. Techniques that can increase the diffraction quality of macromolecular crystals can therefore be essential in the successful conclusion of these challenging projects. No technique is universal but encouraging results have been recently achieved by carrying out the controlled dehydration of crystals of biological macromolecules. A new device that delivers a stream of air with a precisely controlled relative humidity to the complicated sample environment found at modern synchrotron beamlines has been conceived at the EMBL Grenoble and developed by the EMBL and the ESRF as part of the SPINE2 complexes project, a European Commission funded protein structure initiative. The device, the HC1b, has been available for three years at the ESRF macromolecular crystallography beamlines and many systems have benefitted from on-line controlled dehydration. Here we describe a standard dehydration experiment, highlight some successful cases and discuss the different possible uses of the device.
近年来，大量多组分复合物和膜蛋白晶体结构的数量不断增加，可以归因于许多因素，例如更好的蛋白质表达和纯化系统、高通量结晶技术的出现以及第三代同步辐射源的出现。然而，许多系统往往会产生在衍射性质上非常不均匀的晶体。这在许多情况下阻止了收集具有足够质量以产生有用的生物或相位信息的衍射数据。因此，能够提高大分子晶体衍射质量的技术在成功完成这些具有挑战性的项目中至关重要。没有一种技术是通用的，但最近通过对生物大分子晶体进行受控脱水已经取得了令人鼓舞的结果。一种新的设备，能够向现代同步加速器光束线复杂的样品环境输送具有精确控制的相对湿度的气流，该设备由 EMBL 格勒诺布尔提出，并由 EMBL 和 ESRF 作为 SPINE2 复合物项目的一部分开发，这是一个由欧盟委员会资助的蛋白质结构计划。该设备，即 HC1b，已经在 ESRF 大分子晶体学光束线上使用了三年，许多系统已经受益于在线控制脱水。在这里，我们描述了一个标准的脱水实验，强调了一些成功的案例，并讨论了该设备的不同可能用途。
