Vesterman B, Saulitis J, Betins J, Liepins E, Nikiforovich G V
Institute of Organic Synthesis, Latvian S.S.R. Academy of Science, Riga, USSR.
Biochim Biophys Acta. 1989 Oct 5;998(2):204-9. doi: 10.1016/0167-4838(89)90274-4.
The dynamical space structure of the Leu-enkephalin molecule in DMSO solution was described combining the ROE measurements and Monte Carlo energy calculations. The statistical weights for possible Leu-enkephalin conformers were estimated by comparing the NMR-experimental parameters and the same parameters average over statistical samples of molecular structures obtained by Monte Carlo techniques for every low-energy conformer. The statistical weight estimations reveal that the Leu-enkephalin molecule in DMSO solution is apparently represented by a mixture of at least two peptide backbone conformers with the mean statistical weight values of 70% and 30%. Both conformers possess significant local conformational fluctuations. Each of them represents a folded backbone structure with the folding at the Gly2-Gly3 and Gly3-Phe4 fragments occurring simultaneously in solution.
结合旋转 Overhauser 效应（ROE）测量和蒙特卡罗能量计算，描述了亮氨酸脑啡肽分子在二甲基亚砜（DMSO）溶液中的动态空间结构。通过比较核磁共振（NMR）实验参数与通过蒙特卡罗技术对每个低能量构象异构体获得的分子结构统计样本的相同参数平均值，估计了亮氨酸脑啡肽可能构象异构体的统计权重。统计权重估计表明，DMSO 溶液中的亮氨酸脑啡肽分子显然由至少两种肽主链构象异构体的混合物组成，其平均统计权重值分别为 70%和 30%。两种构象异构体都具有显著的局部构象波动。它们各自代表一种折叠的主链结构，在溶液中 Gly2 - Gly3 和 Gly3 - Phe4 片段同时发生折叠。
