Abstract
The study of protein dynamics using the measurement of relaxation times by NMR was based on a set of studies in the mid-20th century that outlined theories and methods. However, the complexity of protein NMR was such that these simple experiments were not practical for application to proteins. The advent of techniques in the 1980s for isotopic labeling of proteins meant that pulse sequences could now be applied in multidimensional NMR experiments to enable per-residue information about the local relaxation times. One of the earliest advances was published in Biochemistry in 1989. The paper "Backbone dynamics of proteins as studied by (15)N inverse detected heteronuclear NMR spectroscopy: application to staphylococcal nuclease" by Lewis Kay, Dennis Torchia, and Ad Bax delineated a set of pulse sequences that are used with minor modifications even today. This paper, with others from a limited number of other laboratories, forms the basis for the experimental determination of the backbone dynamics of proteins. The biological insights obtained from such measurements have only increased in the past 30 years. Sometimes, the best and perhaps only way to advance a field is an advancement in the technical capabilities that allows new perspectives to be reached.