Protein Crystallography through Supramolecular Interactions between a Lanthanide Complex and Arginine

Crystal clear: Strong supramolecular interactions between tris(dipicolinate)lanthanide complexes and arginine-like moieties have been evidenced by NMR chemical shift titration and X-ray diffraction analyses. Since the lanthanide atom is a strong anomalous scatterer, and the complex itself is luminescent, this interaction could be used as a powerful tool in the preparation of crystals of protein derivatives with high phasing power.