Velocity-dependent mechanical unfolding of bacteriorhodopsin is governed by a dynamic interaction network.

ABSTRACT: Bacteriorhodopsin is a model system for membrane proteins. This seven transmembrane helical protein is embedded within a membrane structure called purple membrane. Its structural stability against mechanical stress was recently investigated by atomic force microscopy experiments, in which single proteins were extracted from the purple membrane. Here, we study this process by all-atom molecular dynamics simulations, in which single bacteriorhodopsin molecules were extracted and unfolded from an atomistic purple membrane model. In our simulations, key features from the experiments like force profiles and location of key residues that resist mechanical unfolding were reproduced. These key residues were seen to be stabilized by a dynamic network of intramolecular interactions. Further, the unf

SUBMITTER: Kappel C 

PROVIDER: S-EPMC3037603 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature