Stereospecificity of amino acid side chains in deltorphin defines binding to opioid receptors
作者:Lawrence H. Lazarus、Severo Salvadori、Gianfranco Balboni、Roberto Tomatis、William E. Wilson
DOI:10.1021/jm00085a009
日期:1992.4
[des-His4]deltorphin A and [des-His4] analogues containing consecutive D-amino acid replacements in the remaining residues exhibited weak binding to delta receptors and poor delta selectivity. Substitution of D-Met2 in deltorphin A by D-Ala or D-Nle decreased delta selectivities 3-6-fold through an elevation in mu affinities; however, the converse replacement, D-Met for D-Ala2 in deltorphin B, diminished
一系列的deltorphin A的单个D-氨基酸替代类似物,其中一些与His4缺失结合,用于探测大鼠脑阿片受体对肽结合参数的侧链方向的改变。残基1、3和5中具有D-氨基酸的肽主要表现出对δ受体的亲和力降低(88-1200倍),相对于deltorphin A的选择性降低了13-64倍(Ki delta = 0.45 nM; Ki mu / Ki delta = 764):位于N端“消息”域中的芳香族侧链Tyr1和Phe3和位于C端“地址”域中的Leu5芳基侧链似乎起着至关重要的作用赋予高增量亲和力和选择性。尽管D-His4仅将delta亲和力降低了6倍,选择性降低了4倍,他的似乎参与了两个域的组成部分:[des-His4] deltorphin A和[des-His4]类似物在其余残基中包含连续的D-氨基酸替代,表现出与δ受体的结合力弱和δ选择性差。D-Ala或D-Nle替代deltorphin