Journal of Physical Chemistry B, Vol.112, No.47, 15134-15139, 2008
Caching of a Chameleon Segment Facilitates Folding of a Protein with End-to-End beta-Sheet
We report results from all-atom simulations of a 49-residue C-terminal fragment of TOP7 in implicit solvent. Using parallel tempering simulations with high statistics, we probe the thermodynamic properties of the protein over a large range of temperatures and evaluate its free energy landscape at room temperature. Our results confirm that the protein folds by a caching mechanism that relies on a chameleon segment. This mechanism differs from the one seen in high-temperature unfolding simulations. Finally, we discuss a possible mechanism for dimerization of the protein.