Mechanical unfolding of acylphosphatase studied by single-molecule force spectroscopy and MD simulations.

ABSTRACT: Single-molecule manipulation methods provide a powerful means to study protein transitions. Here we combined single-molecule force spectroscopy and steered molecular-dynamics simulations to study the mechanical properties and unfolding behavior of the small enzyme acylphosphatase (AcP). We find that mechanical unfolding of AcP occurs at relatively low forces in an all-or-none fashion and is decelerated in the presence of a ligand, as observed in solution measurements. The prominent energy barrier for the transition is separated from the native state by a distance that is unusually long for alpha/beta proteins. Unfolding is initiated at the C-terminal strand (beta(T)) that lies at one edge of the beta-sheet of AcP, followed by unraveling of the strand located at the other. The central stran

SUBMITTER: Arad-Haase G 

PROVIDER: S-EPMC2895382 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature