CONFORMATIONAL BACKBONE DYNAMICS OF THE CYCLIC DECAPEPTIDE ANTAMANIDE - APPLICATION OF A NEW MULTICONFORMATIONAL SEARCH ALGORITHM-BASED ON NMR DATA
CONFORMATIONAL BACKBONE DYNAMICS OF THE CYCLIC DECAPEPTIDE ANTAMANIDE - APPLICATION OF A NEW MULTICONFORMATIONAL SEARCH ALGORITHM-BASED ON NMR DATA
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DOI：
10.1021/bi00092a005
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发表时间：
1993-10-19
期刊：
影响因子：
2.9
通讯作者：
ERNST, RR
中科院分区：
文献类型：
--
作者：
BLACKLEDGE, MJ;BRUSCHWEILER, R;ERNST, RR
在快速构象动力学条件下，核磁共振分析生物分子结构的一般方法已应用于环十肽安他胺的研究。二维实验、旋转框架中的弛豫测量、同核和异核耦合常数的测定已被用于表征分子的动态特性，并结合了一种用于研究多构象平衡的新型搜索算法。从旋转框架弛豫测量中获得了存在构象交换过程的直接证据，活化能约为20 kJ mol-1，交换寿命约为25 mus，温度为320 K。这一证据与来自多构象搜索算法MEDUSA的信息相结合，提出了在动态交换平衡中共存的结构集。
A general procedure for the analysis of biomolecular structures by NMR in the presence of rapid conformational dynamics has been applied to the study of the cyclic decapeptide antamanide. Two-dimensional experiments, relaxation measurements in the rotating frame, and homo- and heteronuclear coupling constant determinations have been used to characterize the dynamic properties of the molecule, in combination with a novel search algorithm for investigating multiconformational equilibria. Direct evidence for the presence of a conformational exchange process with an activation energy of approximately 20 kJ mol-1 and an exchange lifetime of approximately 25 mus at 320 K has been obtained from rotating frame relaxation measurements. This evidence is combined with the information derived from the multiconformational search algorithm MEDUSA to propose sets of structures that coexist in a dynamic exchange equilibrium.