Nolandt Olga V, Walther Torsten H, Grage Stephan L, Ulrich Anne S
Karlsruhe Institute of Technology (KIT), Institute of Organic Chemistry and DFG-Center for Functional Nanostructures, Fritz-Haber-Weg 6, D-76131 Karlsruhe, Germany.
Biochim Biophys Acta. 2012 May;1818(5):1142-7. doi: 10.1016/j.bbamem.2012.01.007. Epub 2012 Jan 17.
A mixture of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) with the short-chain detergent n-dodecylphosphocholine (DPC) is introduced here as a new membrane-mimetic bicelle system for solid-state NMR structure analysis of membrane proteins in oriented samples. Magnetically aligned DMPC/DPC bicelles are stable over a range of concentrations, with an optimum lipid ratio of q=3:1, and they can be flipped with lanthanide ions. The advantage of DMPC/DPC over established bicelle systems lies in the possibility to use one and the same detergent for purification and NMR analysis of the membrane protein, without any need for detergent exchange. Furthermore, the same batch of protein can be studied in both micelles and bicelles, using liquid-state and solid-state NMR, respectively. The applicability of the DMPC/DPC bicelles is demonstrated here with the (15)N-labeled transmembrane protein TatA.
本文介绍了一种由1,2-二肉豆蔻酰-sn-甘油-3-磷酸胆碱（DMPC）与短链去污剂正十二烷基磷酸胆碱（DPC）组成的混合物，作为一种新型的膜模拟双分子层体系，用于对取向样品中的膜蛋白进行固态核磁共振结构分析。磁取向的DMPC/DPC双分子层在一系列浓度范围内都很稳定，最佳脂质比为q = 3:1，并且可以用镧系离子翻转。DMPC/DPC相对于已建立的双分子层体系的优势在于，有可能使用同一种去污剂对膜蛋白进行纯化和核磁共振分析，而无需进行去污剂交换。此外，同一批蛋白质可以分别使用液态核磁共振和固态核磁共振在胶束和双分子层中进行研究。本文用（15）N标记的跨膜蛋白TatA证明了DMPC/DPC双分子层的适用性。
