NMR Spectroscopy in the Analysis of Protein-Protein Interactions

Protein-protein interactions are a central aspect of biology and NMR spectroscopy is one of the most powerful and versatile methods available to characterize their structure, dynamics, kinetics and thermodynamics. In this article, we give an overview of the suite of approaches available to the researcher who wishes to understand their favourite protein-protein interaction in more detail. We begin with an outline of two fundamental concepts that are important for understanding the strengths and limitations of NMR spectroscopy – nuclear spin relaxation and chemical exchange. We then present a range of methods including chemical shift perturbation analysis, nuclear Overhauser effects (and its derivatives), residual dipolar couplings, paramagnetic approaches, solid-state NMR and the analysis of low-abundance species. Each method is accompanied by recen texamples from the literature. Together, these techniques can allow both broad and deep insight into the mechanistic underpinnings of protein-protein interactions.