High-speed AFM images of thermal motion provide stiffness map of interfacial membrane protein moieties.

ABSTRACT: The flexibilities of extracellular loops determine ligand binding and activation of membrane receptors. Arising from fluctuations in inter- and intraproteinaceous interactions, flexibility manifests in thermal motion. Here we demonstrate that quantitative flexibility values can be extracted from directly imaging the thermal motion of membrane protein moieties using high-speed atomic force microscopy (HS-AFM). Stiffness maps of the main periplasmic loops of single reconstituted water channels (AqpZ, GlpF) revealed the spatial and temporal organization of loop-stabilizing intraproteinaceous H-bonds and salt bridges.

SUBMITTER: Preiner J 

PROVIDER: S-EPMC4296598 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature