Program

P.27 -- Poster, IWTCP-3

Date: Wednesday, 29 July 2015

Time: 08h30 - 10h00

PROTEIN REFOLDING UNDER AN EXTERNAL MECHANICAL FORCE

Maksim Kouza (1), Pham Dang Lan (2), Mai Suan Li (2,3)

(1) Laboratory of Theory of Biopolymers, Faculty of Chemistry, University of Warsaw; (2) Institute for Computational Sciences and Technology, Ho Chi Minh City, Vietnam; (3) Institute of Physics, Polish Academy of Sciences, Warsaw, Poland

With recent advances in single molecule manipulation techniques, it has become possible to control folding behavior of biological molecules and to obtain unprecedented information about physical basis of the refolding process [1]. The intrinsic parameters of free energy landscape, such as the distance between transition state and native state, $x_F$, and the folding time in the absence of force, $\tau^0_F$, can be reconstructed from force-dependent quantities using Bell’s theory, $\tau_F = \tau^0_{F}exp(-fx_{F}/k_{B}T)$. Using off-lattice Go model and the Langevin dynamics, we have confirmed the exponential dependence of refolding time on external force for 20 different proteins. We discuss the $x_F$ correlations with (1) mechanical unfolding parameters, such as mechanical stability, $f_U$, and the distance between unfolded and transition states, $x_U$, as well as (2) topological descriptors such as contact order and fraction of secondary structure content. With the help of discovered empirical relationships we propose predictive tools which would allow one to characterize unstudied experimentally proteins and to detect the proteins with desired properties. [1] S. Kumar and M. S. Li, Biomolecules under mechanical force, Phys. Reports 486, 1-74 (2010)

Presenter: Pham Dang Lan