Unveiling the transition path region in the one-dimensional free energy landscape of proteins

The objective of the present work is to demonstrate a robust way to pin down the exact location of transition path region (TPR([(TPR)_F,(TPR)_U])) along the reaction coordinate. The Brownian dynamics and Monte-Carlo simulations of the folding trajectories were performed on three analytical free energy landscapes (FELs). The estimated TPR was found to capture the anharmonicity in the transition state of the FELs. The study emphasizes that the methods used for the estimation of TPR must include the features of FELs as these features decide the configurational entropy associated with anharmonic motions of a protein in the metastable states.