A fresh new look at an old technique in protein biochemistry has shown that it should be reintroduced to the spectroscopy toolkit.
For decades, scientists have used nuclear magnetic resonance (NMR) spectroscopy to probe the molecular motions of proteins on various timescales. This technique has revealed aspects of enzyme reactions, protein folding and other biological processes, all on an atomic scale.
Typically, spectroscopists will gauge the rotation of NMR-active atoms in the protein backbone with and without proton irradiation to calculate a ratio known as a steady-state nuclear Overhauser effect (NOE); however, it was not always done this way.
Before steady-state NOE experiments became the norm in biological investigations, scientists would often take a greater number of measurements over the course of an irradiation experiment. This method, termed “dynamic” NOE, might seem more complicated, but according to Ph.D. student Vladlena Kharchenko, it