Hassan M, Goodman M
Biochemistry. 1986 Nov 18;25(23):7596-606. doi: 10.1021/bi00371a050.
Molecular dynamics simulations and energy minimization studies of cyclic enkephalin analogues incorporating retro-inverso modifications have been carried out. The dynamic trajectories are analyzed in terms of the relative mobility of the 14-membered rings, conformational transitions among equilibrium states, and hydrogen-bonding patterns. The cyclization of the molecules reduces the motion of the ring structures substantially. Time-correlated conformational transitions resulting in the reorientation of peptide units are observed. Hydrogen bonds form principally C7 structures. Because of the incorporation of retro-inverso residues, C6 and C8 structures are also formed. Starting conformations for energy minimizations were obtained from the molecular dynamics simulations and from a systematic search of the conformational space available to the molecules. Several minimum energy backbone and side-chain conformations were found for each analogue. The effect of retro-inverso residues on hydrogen-bonding patterns and backbone conformations is discussed.
已对包含反向异构修饰的环脑啡肽类似物进行了分子动力学模拟和能量最小化研究。根据14元环的相对迁移率、平衡态之间的构象转变以及氢键模式对动态轨迹进行了分析。分子的环化大大降低了环结构的运动。观察到导致肽单元重新定向的时间相关构象转变。氢键主要形成C7结构。由于引入了反向异构残基，也形成了C6和C8结构。能量最小化的起始构象是从分子动力学模拟以及对分子可用构象空间的系统搜索中获得的。为每个类似物找到了几种最低能量的主链和侧链构象。讨论了反向异构残基对氢键模式和主链构象的影响。
