XAS examination of glutathione-cobalt complexes in solution.

XAS examination of glutathione-cobalt complexes in solution.
J Inorg Biochem. 2014 Nov 1;142C:126-131
Authors: Bresson C, Spezia R, Solari PL, Jankowski CK, Den Auwer C
Abstract
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.
PMID: 25450027 [PubMed - as supplied by publisher]

Source: Journal of Inorganic Biochemistry - November 1, 2014 Category: Biochemistry Authors: Bresson C, Spezia R, Solari PL, Jankowski CK, Den Auwer C Tags: J Inorg Biochem Source Type: research