XAS examination of glutathione-cobalt complexes in solution.
In the present work, we have investigated the coordination modes of cobalt with glutathione (γ-l-glutamyl-l-cysteinyl-glycine, GSH). A systematic study of cobalt-GSH complexes at basic and neutral pH has been undertaken with a multi-spectroscopic approach combined with quantum chemistry calculations. XAS (x-ray absorption spectroscopy) has been performed at the cobalt K edge in order to shed light into the cation coordination sphere and formal oxidation states. XANES (x-ray absorption near edge structure) enabled to show that in basic and neutral media, cobalt oxidation state is equal to +III and +II respectively. EXAFS (extended x-ray absorption fine structure) provided indications on the donor atoms involved in the coordination with cobalt as well as the bond lengths. DFT (density functional theory)-based calculations and NMR experiments have been performed to assess the most stable structure of the cobalt-GSH complex in basic conditions.
['Bresson|Carole|C|', 'Spezia|Riccardo|R|', 'Solari|Pier Lorenzo|PL|', 'Jankowski|Christopher K|CK|', 'Den Auwer|Christophe|C|']
D003035:Cobalt D056831:Coordination Complexes D005978:Glutathione D056928:X-Ray Absorption Spectroscopy
XAS Cobalt Glutathione DFT NMR