Probing Multivalent Interactions in a Synthetic Host鈥揋uest Complex by Dynamic Force Spectroscopy

详细信息    查看全文

• 作者：Alberto Gomez-Casado ; Henk H. Dam ; M. Deniz Yilmaz ; Daniel Florea ; Pascal Jonkheijm ; Jurriaan Huskens
• 刊名：Journal of the American Chemical Society
• 出版年：2011
• 出版时间：July 20, 2011
• 年：2011
• 卷：133
• 期：28
• 页码：10849-10857
• 全文大小：1029K
• 年卷期：v.133,no.28(July 20, 2011)
• ISSN：1520-5126

文摘

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/尾-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.