Effects of two solvent conditions on the free energy landscape of the BBL peripheral subunit binding domain.

ABSTRACT: BBL is a small independently folding domain with two main parallel helices. The experiment of C(α) secondary shifts has shown that changing the pH from ~7 to ~5 results in the reduced helicity at the C-terminus of helix 2. Combining constant pH molecular dynamics with replica exchange, we sampled the protein conformation space and protonation states extensively under a neutral pH condition and an acidic condition. Our results reveal that the solvent conditions influence the free energy landscape. Under the neutral pH condition, the denatured state and the native state are well separated. The condition of the acidic pH reshapes the free energy surface, leading to a broadly populated denatured-state basin and a low free energy barrier between the denatured state and the native state. The aci

SUBMITTER: Liu H 

PROVIDER: S-EPMC3257382 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature