Analysis of three-dimensional structure of ion channel peptides bound to phospholipid bilayers by high resolution solid state NMR

在这一研究项目中，我们研究了一种新的方法，以确定膜连接通道肽的三维结构和方向。在这一研究项目中取得的结果。（1） The three-dimensional structure of [イイD113イエD1C，イイD115イエD1N]-labeled Leu-enkephalin （tyr-Gly-Gly-Phe-Leu） dihydrate crystals was determined on the basis of six sets of accurately determinedイD11C-イD115イD1N interatomic distances by rotational double resonance （REDOR） and some additional constraints from echo D11C chemical shifts。（2）用同位素双重标记的N-乙酰-Pro-Gly-Phe晶体的间原子距离，从旋转回波双共振（REDOR）实验中获得，对观察的核中的三自旋系统进行了分析，并对任何观察的核都完全耦合在一起，用同位素标记的内部和间分子异构核中。在特定的、中间分子的二聚体相互作用中，研究了一种线索，即将一种分子与周围邻居的相对方向。我们已经制定了一个系统程序，以确定内部和间分子相互间距离，以及三个相互间矢量之间的角度。（3） The conformation and dynamics of melittin bound to the dimyristoylphophatidylcholin （DMPC） bilayer and the magnetic orientation in the lipid bilayer systems were investigated by solid-stateイD131イエD1P andイイD113イエD1C NMR spectroscopy。使用D131-D1 P核磁共振，发现了一种以液态水晶球凝胶相转换温度为平行的长轴延伸的载体，该载体以磁性方向延伸到液态水晶球凝胶相转换温度。伊D113伊D1C NMR spectra were observed on the伊D113伊D1C labeled melittin bound to the lipid bilayers。最后，我们发现了一个melittin采用了一个跨膜器a-helix，其中平均轴与bilayer normal平行。

In this research project, we have studied to achieve a new approach to determine the three-dimensional structure and orientation of membrane bound ion channel peptides. Following results were obtained in this research project.(1) The three-dimensional structure of [ィイD113ィエD1C, ィイD115ィエD1N]-labeled Leu-enkephalin (tyr-Gly-Gly-Phe-Leu) dihydrate crystals was determined on the basis of six sets of accurately determined ィイD113ィエD1C-ィイD115ィエD1N interatomic distances by rotational echo double resonance (REDOR) and some additional constraints from ィイD113ィエD1C chemical shifts.(2) Interatomic distances of isotopically doubly labeled N-Acetyl-Pro-Gly-Phe crystals, obtained from rotational echo double resonance (REDOR) experiments, were analyzed as a three-spin system in which observed nuclei are simultaneously coupled with isotopically labeled intra- and intermolecular heteronuclei. In particular, the intermolecular dipolar interaction was examined to obtain a clue as to the relative orientation of a given molecule to the surrounding neighbors. We have developed a systematic procedure to determine both the intra- and intermolecular interatomic distances and the angle between three two interatomic vectors.(3) The conformation and dynamics of melittin bound to the dimyristoylphophatidylcholin (DMPC) bilayer and the magnetic orientation in the lipid bilayer systems were investigated by solid-state ィイD131ィエD1P and ィイD113ィエD1C NMR spectroscopy. Using ィイD131ィエD1P NMR, it was found that melittin-DMPC bilayer system forms magnetically oriented elongated vesicles with the long axis parallel to the magnetic field above the liquid crystalline-gel phase transition temperature. ィイD113ィエD1C NMR spectra were observed on the ィイD113ィエD1C labeled melittin bound to the lipid bilayers. Finally, it was found that melittin adopts a transmembrane a-helix whose average axis is parallel to the bilayer normal.