Probing Multivalent Interactions in a Synthetic Host-Guest Complex by Dynamic Force Spectroscopy
Probing Multivalent Interactions in a Synthetic Host-Guest Complex by Dynamic Force Spectroscopy
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DOI：
10.1021/ja2016125
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发表时间：
2011-07-20
影响因子：
15
通讯作者：
Huskens, Jurriaan
中科院分区：
文献类型：
--
作者：
Gomez-Casado, Alberto;Dam, Henk H.;Huskens, Jurriaan
多价存在于许多生物和合成系统中。多价的成功应用取决于对这种现象的热力学和动力学的正确理解。在本文中，我们利用合成金刚烷/β-环糊精模型系统，通过力谱技术研究多价键的稳定性和强度。将实验结果与断裂力和动力学解离速率的理论预测进行比较，我们发现，当复合物的化合价从单价增加到二价到三价时，会从准平衡（断裂力恒定为 99 pN）转变为动力学依赖状态，加载速率依赖的断裂力从 140 到 184 pN（二价）和 175 到 210 pN （三价）。还鉴定了其他结合几何形状、平行单价断裂、单结合二价断裂以及单结合和双结合三价断裂。多价复合物的实验动力学解离速率表明，复合物的稳定性随着键的数量而显着增强，这与非合作多价模型的预测一致。
Multivalency is present in many biological and synthetic systems. Successful application of multivalency depends on a correct understanding of the thermodynamics and kinetics of this phenomenon. In this Article, we address the stability and strength of multivalent bonds with force spectroscopy techniques employing a synthetic adamantane/beta-cyclodextrin model system. Comparing the experimental findings to theoretical predictions for the rupture force and the kinetic off-rate, we find that when the valency of the complex is increased from mono- to di- to trivalent, there is a transition from quasi-equilibrium, with a constant rupture force of 99 pN, to a kinetically dependent state, with loading-rate-dependent rupture forces from 140 to 184 pN (divalent) and 175 to 210 pN (trivalent). Additional binding geometries, parallel monovalent ruptures, single-bound divalent ruptures, and single- and double-bound trivalent ruptures are identified. The experimental kinetic off-rates of the multivalent complexes show that the stability of the complexes is significantly enhanced with the number of bonds, in agreement with the predictions of a noncooperative multivalent model.