Functional and structural characterization of membrane-binding proteins using NMR

Abstract

Membrane-binding proteins play a central role in various biological processes through interactions with the surface of biomembranes, which are intrinsically mobile and inhomogeneous. Therefore, unlike integral membrane proteins, membrane-bound protein structures tend to be inhomogeneous. In addition, large regions of membrane-binding proteins are exposed to the aqueous phase, resulting in broad distributions of global and local dynamic properties. In vitro, protein dynamics are influenced by the phase of biomimetic model membranes. Therefore, solution and solid-state NMR techniques must be used complementary to investigate the broad distribution of protein mobilities. Scalar- and dipolar coupling-based solid-state NMR techniques can characterize proteins that are strongly bound to the fluid and gel phases of membranes, respectively. Alternatively, advanced solution NMR techniques can be used to characterize proteins that are weakly bound to membranes.