Johnson Matthew C, Schmidt-Krey Ingeborg
Georgia Institute of Technology, School of Biology, Atlanta, GA, USA.
Methods Cell Biol. 2013;113:325-37. doi: 10.1016/B978-0-12-407239-8.00015-X.
Two-dimensional (2D) crystals of integral membrane proteins, comprising ordered protein reconstituted into a synthetic lipid bilayer, can be induced to form from detergent solubilized and purified membrane protein sources via the addition of exogenous lipid and the subsequent removal of the solubilizing detergent. This is most commonly accomplished by dialysis of a small volume of ternary protein-detergent-lipid mixture against a large volume of buffer, and can be carried out using common, easily available materials. Following successful crystallization, electron crystallographic data obtained by electron cryo-microscopy (cryo-EM) of vitrified 2D crystals can be used to determine the structure of the lipid bilayer-embedded integral membrane protein.
整合膜蛋白的二维（2D）晶体由重组到合成脂质双层中的有序蛋白质组成，通过添加外源脂质并随后去除增溶去污剂，可从去污剂增溶和纯化的膜蛋白来源诱导形成。这最常见的方法是将少量三元蛋白质-去污剂-脂质混合物对大量缓冲液进行透析，并且可以使用常见的、容易获得的材料来进行。成功结晶后，通过对玻璃化二维晶体进行电子冷冻显微镜（cryo-EM）获得的电子晶体学数据可用于确定嵌入脂质双层的整合膜蛋白的结构。
