Flow charts for the systematic solid-state 19F/2H-NMR structure analysis of membrane-bound peptides

Abstract Solid-state NMR (SSNMR) is one of the most useful methods to investigate membrane-bound peptides and proteins, in order to elucidate the structural basis of their diverse biological functions. In the case of short peptides, SSNMR is now performed on a routine basis in several labs. By employing side-chain 19F- or 2H-isotope-labelled peptides in static oriented samples, SSNMR can provide information about conformation, alignment, dynamics, oligomerization, and aggregation behaviour. Changes in and transitions between these structural properties tend to be directly related to the functional mechanism of the peptides. Here, we present an easy-to-follow description of the methodological SSNMR approach in the form of flow charts. The successive steps needed, from peptide synthesis and functional tests, on to NMR sample preparation and NMR experiments, and further on to data analysis, are described. At each stage, questions to be answered and tasks to be performed are explained, and some representative results are illustrated. Relevant challenges and pitfalls are discussed, and possible reasons for problems and their possible solutions are considered.