Protein surface recognition and covalent binding by chromium nitrilotriacetate complexes: elucidation using NMR and CD spectroscopies

Abstract

New approaches to delineate sites of noncovalent and covalent binding by small metal complexes on a protein surface are described. The complexes employed are based on the chromium(III) nitrilotriacetate framework substituted with amino acid side chain groups. The protein examined is the well-characterized hen egg white lysozyme. Noncovalent binding location and mode have been studied by the technique of nuclear Overhauser effect quenching, along with paramagnetic relaxation experiments. These methods allow the elucidation of two major and two minor binding sites on the protein surface