NMR spectroscopy offers the possibility of characterising the chemical conversion of compounds by catalytically active proteins (enzymes). It is possible to observe both the reaction process itself and structural changes in the enzyme during the catalytic reaction. Current examples from our research group concern the degradation of ribonucleic acids by PR-10 proteins, a family of ribonucleases that is widespread in nature. For the first time, we were able to characterise the mechanism of RNA degradation for this protein family in detail. In the first step, single-stranded RNA segments are bound into a cavity of the PR-10 proteins. Only in the second step the RNA chain is hydrolytically cut into fragments on the protein surface and released.
Single-stranded RNA bound to a PR-10 protein. NMR spectroscopic identification of the catalytically active centres on the protein surface.