【摘要】 <正> 多肽的构象研究除了可以用X-射线晶体学及二维核磁共振等实验方法外,理论计算的方法有系统搜索法、蒙特卡洛方法、距离几何方法、分子动力学方法及能量极小化等.系统搜索法具有构象空间搜索彻底的特点,相对来说找到系统整体极小值的可能性较大,但由于其计算量较大,对于多肽及蛋白质很难实现.我们对系统搜索法进行了简化,不是同时旋转所有的二面角,而是成对地进行,以迭代的方法达到收敛,最后得到可能的构象.更多还原

【Abstract】 A simplified systematic search method for peptide conformational analysis wasestablished,which changes subsequent main chain dihedral angles two by two by anincrement of 10 degrees and selects low energy conformations according to energycontour maps.The characteristics of the method is the computational speed.It wasapplied to the conformational analysis of two linear pentapeptides which can cyclizeto give a same product.The lowest energy conformations of both peptides show aturn-like structure.The distance between N₁ atom and C₅ atom correlates well withthe cyclization reaction yield.更多还原