Ultraviolet Resonance Raman Spectroscopic Study on the Conformation of Enkephalin and Binding Mode to Receptors

脑啡肽构象及受体结合方式的紫外共振拉曼光谱研究

基本信息

批准号：
01470142
负责人：
TAKEUCHI Hideo
金额：
$ 0.77万
依托单位：
Tohoku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1990
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-01470142/
关键词：
Enkephalin Opioid Receptor UV resonance Raman spectroscopy ラマン分光赤外分光 βタ-ン

项目摘要

We have studied the ultraviolet (213- and 240-nm) resonance Raman (UVRR) spectra of Met-enkephalin, Leu-enkephalin, and [Trp^4] Met-enkephalin incorporated into dilauroylphatidylcholine liposomes. The analysis of the spectra based on the data of model compounds obtained previously has provided several pieces of important information on the binding mode of enkephalin to the lipid bilayers. A delta-type opioid receptor has been extracted from rat brain and purified. The structure of the receptor has been investigated by UVRR and circular dichroism spectroscopy. The results obtained are as follows :1. Every enkephalin mentioned above exists as an ensemble of various extended conformers in aqueous solution, whereas it takes a folded conformation in the lipid-bound state.2. The Tyr side chain is inserted into the membrane hydrophobic interior, but the Phe side chain is located in the polar surface region or exposed to the aqueous phase.3. The degree of insertion of Tyr into the membrane is smaller for Leu-enkephalin than the other two.4. The deeper the Tyr is buried, the higher the affinity and activity of the peptide.5. The membrane environment is considered to play a role in protecting the N-terminal Tyr form degradation in tissues.6. The mainchain of the delta-opioid receptor is largely in the beta-sheet structure and the protein does not contain many aromatic residues, particularly Tyr and Typ.

我们研究了掺入二月桂酰磷脂酰胆碱脂质体中的甲硫氨酸脑啡肽、亮氨酸脑啡肽和 [Trp^4]甲硫氨酸脑啡肽的紫外（213 和 240 nm）共振拉曼 (UVRR) 光谱。基于先前获得的模型化合物数据的光谱分析提供了关于脑啡肽与脂质双层的结合模式的一些重要信息。从大鼠脑中提取并纯化了δ型阿片受体。通过 UVRR 和圆二色光谱研究了受体的结构。得到的结果如下： 1．上述每种脑啡肽在水溶液中均以多种延伸构象的集合形式存在，而在脂质结合状态下则呈折叠构象。 2． Tyr侧链插入膜疏水内部，Phe侧链位于极性表面区域或暴露于水相。3．亮氨酸脑啡肽的Tyr插入膜的程度比其他两者小。4． Tyr埋藏越深，肽的亲和力和活性越高。5．膜环境被认为在保护组织中N端Tyr不被降解方面发挥着作用。6． δ-阿片受体的主链主要位于β-折叠结构中，并且蛋白质不包含许多芳香族残基，特别是Tyr和Typ。