Forced Kramers escape in single-molecule pulling experiments.

Yu-Jane Sheng; Shaoyi Jiang; Heng-Kwong Tsao

doi:10.1063/1.2046632

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Forced Kramers escape in single-molecule pulling experiments.

Yu-Jane Sheng·Shaoyi Jiang·Heng-Kwong Tsao

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Abstract

The pulling-induced rupture of noncovalent bonds is studied by the overdamped Kramers theory with full account of a time-varying barrier. Mechanic pulling reduces the energy barrier and leads to loading-rate dependence of the rupture force F(u)(F(t)). Tested against Langevin dynamics, four distinct regimes are identified, including kinetic dominant, weak pulling, strong pulling, and mechanic pulling dominant. Asymptotic analyses show that F(u) approximately ln F(t) in weak pulling regime and becomes 1-(F(u)F(c)) approximately [ln(F(t))E(b)](23) in strong pulling regime. Kinetic informations such as activation energy E(b) and critical force F(c) were extracted from pulling experiments for biotin-streptavidin complex.

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Biotin Chemistry, Physical Computer Simulation Humans Kinetics Ligands Models, Statistical Streptavidin Stress, Mechanical Thermodynamics Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.

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Yu-Jane Sheng, Shaoyi Jiang, Heng-Kwong Tsao. 2005-09-01. Forced Kramers escape in single-molecule pulling experiments.. https://doi.org/10.1063/1.2046632

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