线形脑啡肽(N-Tyr1-Gly2-Gly3-Phe4-Leu5)的NMR溶液构象研究

本文在Bruker AM-400 NMR谱仪上,在不同温度下研究了线形脑啡肽(N-Tyr¹-Gly²-Gly³-Phe⁴-Leu⁵)在DMSO中的NMR溶液构象。由NMR测试结果,得到了NH化学位移温度梯度系数、扭转角φ、χ'约束和¹H-¹H NOE距离约束,用目标函数法计算了脑啡肽的溶液构象,分析了优势边链构象。研究结果指明了多肽骨架的柔变性且处于构象平衡中。

SOLUTION CONFORMATIONAL ANALYSIS OF LINEAR ENKEPHALIN PENTAPEPTIDE (N-Tyr~1-Gly~2-Gly~3-Phe~4-Leu~5)

The conformation of linear enkephalin pentapeptide, N-Tyr¹-Gly²-Gly³-Phe⁴-Leu⁵, in DMSO-d₆ has been investigated on Bruker AM-400 NMR spectrometer at 300K,318K and 336K. The NH-chemical shift temperature gradients, the constraints for torsion angles φ and χ', and the constraints for ¹H-¹H NOE distance were obtained from 1D and 2D NMR measurements. The calculations of enkephalin conformation at 300K, 318K and 336K were carried out on VAX8700 by means of variable target function method. The insight into the backbone conformation is obtained from variable temperature measurements and the results seem to indicate that the backbone is flexible and the peptide is involved in a conformational equilibrium.