Cysteine dioxygenase (CDO) is a mononuclear, non-heme iron-dependent enzyme that converts exogenous cysteine (Cys) to cysteine sulfinic acid using molecular oxygen. Although the complete catalytic mechanism is not yet known, several recent reports presented evidence for an Fe(III)-superoxo reaction intermediate. In this work, we have utilized spectroscopic and computational methods to investiga...

AIMS To investigate Klebsiella oxytoca strain BAS-10 growth on ferric citrate under anaerobic conditions for exopolysaccharide (EPS) production and localization on cell followed by the purification and the EPS determination of the iron-binding stability constant to EPS or biotechnological applications. METHODS AND RESULTS Klebsiella oxytoca ferments ferric citrate under anaerobic conditions a...

The overall six-electron oxidation of water soluble porphyrin Fe(III)TPPS by hydrogen peroxide and peroxomonosulfate ion was studied by the stopped-flow method with UV-vis detection. A three-step consecutive reaction was observed with two intermediates: Fe(III)TPPS --> Int(1)--> Int(2)--> products. The products were identified as the iron(iii) complex of the biliverdin analog formed from TPPS a...

The preparation, characterization, and immobilization of cobalt (III) salen complex on CoFe2O4@SiO2 nanoparticle (CoFe2O4@SiO2@ Co(III) salen complex) are described. Co(III) salen complex loaded on ferrite cobalt-silica nanoparticle is characterized by TEM, SEM-EDX, VSM and FT-IR analyses. The efficiency of CoFe2O...

This work demonstrates that the Fe(III)(H2O2) complex, which has been considered as an unlikely oxidant in P450, is actually very efficient in sulfoxidation reactions. Thus, Fe(III)(H2O2) undergoes a low-barrier nucleophilic attack by sulfur on the distal oxygen, resulting in heterolytic O-O cleavage coupled to proton transfer. We further show that Fe(III)(H2O2) is an efficient sulfoxidation ca...

Liquid-liquid iron(III) extraction was investigated using benzyl fatty hydroxamic acids (BFHAs) and methyl fatty hydroxamic acids (MFHAs) as chelating agents through the formation of iron(III) methyl fatty hydroxamate (Fe-MFHs) or iron(III) benzyl fatty hydroxamate (Fe-BFHs) in the organic phase. The results obtained under optimized conditions, showed that the chelating agents in hexane extract...

The synthesis of iron oxide nano-particles by direct thermal decomposition was studied. Simultaneous thermal analysis and Fourier transform infrared spectroscopy results confirmed the formation of iron-urea complex, and disclosed iron oxide formation mechanism. Calcination of the iron-urea complex at 200°C and 250°C for 2 hrs. resulted in the formation of maghemite along with hematite as a seco...