Abstract Paramagnetic effects from lanthanide ions present powerful tools for protein studies by nuclear magnetic resonance (NMR) spectroscopy provided that the lanthanide can be site-specifically and rigidly attached to the protein. A new, particularly small and rigid lanthanide-binding tag, 3-mercapto-2, 6-pyridinedicarboxylic acid (3MDPA), was synthesized and attached to two different proteins via a disulfide bond. The complexes of ...
