Thrombin receptor-activating peptides (TRAPs): Investigation of bioactive conformations via structure–activity, spectroscopic, and computational studies
作者:Marco A. Ceruso、David F. McComsey、Gregory C. Leo、Patricia Andrade-Gordon、Michael F. Addo、Robert M. Scarborough、Donna Oksenberg、Bruce E. Maryanoff
DOI:10.1016/s0968-0896(99)00180-7
日期:1999.11
TRAP-5 is known to tolerate a wide variety of side chains, but we also found that the amide nitrogen at this position can be substituted by an oxygen, as in SF-psi(COO)-LLR-NH2, without diminishing activity. However, this peptide bond is sensitive to conformational changes in that SFPLR-NH2 was active, whereas SF-NMeL-LR-NH2 was not. Additionally, we found that position 3 does not tolerate rigid spacers
凝血酶受体(PAR-1)是一种不常见的跨膜G蛋白偶联受体,它通过丝氨酸蛋白酶裂解其胞外N端而被激活,从而暴露出激动剂肽配体,并与受体本身拴在一起。包含激动剂基序的合成肽,例如人PAR-1的SFLLRN,能够引起完全的受体活化。我们通过系统引入某些构象扰动(包括α-甲基,酯psi(COO)和还原酰胺psi(CH2N)扫描),将凝血酶受体激活肽(TRAPs)的可能的生物活性构象探究到最低限度激动剂序列(SFLLR),以探测骨架构象和酰胺NH氢键的重要性。我们进行了代表性五肽的广泛构象搜索,以推导假定的生物活性结构家族。此外,我们采用1 H NMR和圆二色性(CD)通过实验表征某些五肽类似物的构象。我们的五肽类似物激活的血小板聚集提供了PAR-1激动剂活性的结构-功能相关性。PAR-1受体结合数据辅助了这种相关性,PAR-1受体结合数据确定了肽配体对凝血酶受体的亲和力,而与源自受体激活(即纯分子