Vanadium Complexes as Prospective Therapeutics: Structural Characterization of a VIV Lysozyme Adduct. Issue 21 (4th June 2014) - Santos, Marino F. A.
Abstract: The biological activity of vanadium complexes, namely, as insulin enhancers, is well known. We report a combined X‐ray crystallography, electron paramagnetic resonance, and density functional theory study of the interaction of vanadium picolinate complexes with hen egg white lysozyme (HEWL). We show that the V IV O(pic)2 complex covalently binds to the COO – group of the side chain of Asp52 of HEWL. The long V IV =O bond obtained in the X‐ray study is explained to be due to reduction of V IV to V III during exposure of the crystals to the intense X‐ray beam. Abstract : Vanadium complexes are recognized as insulin enhancers that can be transported by high‐molecular‐mass serum components. We report studies of the interaction of the antidiabetic vanadium(IV) picolinate complex with hen egg white lysozyme (HEWL). Soaked crystals diffracting up to a resolution of 1.28 Å show that V IV covalently binds to Asp52, two picolinate – ions (pic), and an Ooxido atom.