Marassi F M, Gesell J J, Valente A P, Kim Y, Oblatt-Montal M, Montal M, Opella S J
Department of Chemistry, University of Pennsylvania, Philadelphia 19104, USA.
J Biomol NMR. 1999 Jun;14(2):141-8. doi: 10.1023/a:1008391823293.
The assignment of amide resonances in the two-dimensional PISEMA (Polarization Inversion with Spin Exchange at the Magic Angle) spectrum of uniformly 15N labeled M2 peptide corresponding to the channel-lining segment of the acetylcholine receptor in oriented phospholipid bilayers is described. The majority of the resonances were assigned through comparisons with spectra from selectively 15N labeled recombinant peptides and specifically 15N labeled synthetic peptides. Some resonances were assigned to specific amino acid residues by means of homonuclear 15N spin-exchange spectroscopy. A modification to the conventional spin-exchange pulse sequence that significantly shortens the length of the experiments by combining the intervals for 15N spin-exchange and 1H magnetization recovery is described.
描述了在取向磷脂双层中对应于乙酰胆碱受体通道内衬段的均匀15N标记的M2肽的二维PISEMA（魔角自旋交换极化反转）谱中酰胺共振的归属。通过与选择性15N标记的重组肽和特异性15N标记的合成肽的光谱进行比较，确定了大多数共振峰。通过同核15N自旋交换光谱法将一些共振峰归属到特定的氨基酸残基。描述了对传统自旋交换脉冲序列的一种改进，该改进通过结合15N自旋交换和1H磁化恢复的时间间隔，显著缩短了实验时长。
