Structural insights into the differences among lactisole derivatives in inhibitory mechanisms against the human sweet taste receptor
作者:Tomoya Nakagita、Akiko Ishida、Takumi Matsuya、Takuya Kobayashi、Masataka Narukawa、Takatsugu Hirokawa、Makoto Hashimoto、Takumi Misaka
DOI:10.1371/journal.pone.0213552
日期:——
residues in T1R3-TMD and that the inhibitory potencies of those inhibitors were mainly due to stabilizing interactions mediated via their carboxyl groups in the vertical dimension of the ligand pocket of T1R3-TMD. In addition, 2,4-DP engaged in a hydrophobic interaction mediated by its o-Cl group, and this interaction may be chiefly responsible for the higher inhibitory potency of 2,4-DP.
Lactisole是人类甜味受体的抑制剂,具有2-苯氧基丙酸骨架,并已显示与该受体的T1R3亚基(T1R3-TMD)的跨膜结构域相互作用。与另一种抑制剂骨架共享相同分子骨架的2,4-DP被证实是其抑制活性的强效抑制剂比该抑制剂多10倍。然而,其针对受体的抑制机制的结构基础尚待阐明。最近已经报道了代谢型谷氨酸受体TMD的晶体结构以及T1R被归类为C类G蛋白偶联受体,这使得为T1R3-TMD建立精确的结构模型成为可能。在这个研究中,通过比较乳双酚对T1R3-TMD和2,4-DP的作用来表征抑制甜味的详细结构机理。我们首先使用表达带有突变的甜味受体的培养细胞进行了一系列实验,并研究了与这些抑制剂的相互作用。根据结果,我们接下来进行对接模拟,然后应用基于分子动力学的能量最小化。我们的分析清楚地表明,乳酸酯和2,4-DP的(S)异构体均与T1R3-TMD中的相同七个残基相互作用,并且这些抑制剂的