Pletnev V Z, Tsygannik I N, Fonarev Iu D, Mikhaĭlova I Iu, Kulikov Iu V, Ivanov V T, Langs D A, Duax W L
Bioorg Khim. 1995 Nov;21(11):828-33.
Crystal structure of the complex of meso-valinomycin with KAuCl4 (C60H102N6O18KAuCl4) was determined using direct X-ray diffraction analysis. The conformational state of the complex is similar to that determined earlier for free meso-valinomycin. Characteristic of it is the centrosymmetric bracelet shape stabilized by six intramolecular NH...OC hydrogen bonds of 4 --> 1 type. The K+ ion is located in an inner negatively charged octahedral cavity formed by six carbonyl oxygen atoms of ester groups. The observed differences in conformational angles of the complex and free are caused by readjustment of the geometry of the ion-binding cavity to the size of the ion bound during complexation.
使用直接X射线衍射分析确定了内消旋缬氨霉素与KAuCl4（C60H102N6O18KAuCl4）复合物的晶体结构。该复合物的构象状态与先前确定的游离内消旋缬氨霉素的构象状态相似。其特征是由六个4→1型分子内NH...OC氢键稳定的中心对称手镯形状。K+离子位于由酯基的六个羰基氧原子形成的内部带负电荷的八面体空腔中。复合物和游离物构象角的观察到的差异是由于离子结合腔的几何形状在络合过程中根据结合离子的大小进行了重新调整。
