%0 Journal Article
%T Protein unfolding and refolding as transitions through virtual states
%A L. L. Bonilla
%A A. Carpio
%A A. Prados
%J Physics
%D 2014
%I arXiv
%R 10.1209/0295-5075/108/28002
%X Single-molecule atomic force spectroscopy probes elastic properties of titin, ubiquitin and other relevant proteins. We explain bioprotein folding dynamics under both length- and force-clamp by modeling polyprotein modules as particles in a bistable potential, weakly connected by harmonic spring linkers. Multistability of equilibrium extensions provides the characteristic sawtooth force-extension curve. We show that abrupt or stepwise unfolding and refolding under force-clamp conditions involve transitions through virtual states (which are quasi-stationary domain configurations) modified by thermal noise. These predictions agree with experimental observations.
%U http://arxiv.org/abs/1409.7900v1