Unfolding of a small protein proceeds via dry and wet globules and a solvated transition state.

ABSTRACT: Dissecting a protein unfolding process into individual steps can provide valuable information on the forces that maintain the integrity of the folded structure. Solvation of the protein core determines stability, but it is not clear when such solvation occurs during unfolding. In this study, far-UV circular dichroism measurements suggest a simplistic two-state view of the unfolding of barstar, but the use of multiple other probes brings out the complexity of the unfolding reaction. Near-UV circular dichroism measurements show that unfolding commences with the loosening of tertiary interactions in a native-like intermediate, N(∗). Fluorescence resonance energy transfer measurements show that N(∗) then expands rapidly but partially to form an early unfolding intermediate IE. Fluorescence spe

SUBMITTER: Sarkar SS 

PROVIDER: S-EPMC3838737 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature