An understanding of biological processes at the molecular level comes from knowledge of the atomic structures of biological macromolecules and how they change over time. Knowledge of molecular motions is consequently an indispensible ingredient for a detailed comprehension of the machinery of life. For example, dynamics is at the core of molecular recognition, signaling, ligand binding, catalysis, and folding phenomena. Moreover, dynamics controls the mechanical properties of structural biopolymers. NMR is a natural choice for studying dynamics, with a variety of possible observables that are sensitive to dynamics over timescales from 10−12 to 102 s. This chapter provides an elementary survey of how solid-state NMR can be used to study the dynamics of proteins.
