Quadrupole-Central-Transition ~(17)O NMR Spectroscopy of Protein-Ligand Complexes in Solution

摘要

Although oxygen is ubiquitous in biological molecules such as proteins and nucleic acids, its direct detection by NMR spectroscopy is generally difficult. The natural abundance of the only NMR-active oxygen isotope, ~(17)O, is extremely low (0.037%). In addition, ~(17)O has a quadrupolar nucleus (I= 5/2), which often gives rise to broad NMR signals. On the other hand, ~(17)O NMR parameters are remarkably sensitive to various molecular interactions such as hydrogen bonding and metal ion binding, making ~(17)O NMR an attractive probe of biological structures and dynamics provided that practical difficulties in recording ~(17)O NMR signals can be overcome.