Benzoic acid, sorbic acid, and sodium lauryl sulfate at low concentrations (5 to 10 mg/liter) each effectively inhibited bacterial oxidation of ferrous iron in batch cultures of Thiobacillus ferrooxidans. The rate of chemical oxidation of ferrous iron in low-pH, sterile batch reactors was not substantially affected at the tested concentrations (5 to 50 mg/liter) of any of the compounds.

In the present work, nano scaled zero valent irons (nZVI) were synthesized in ethanol medium by the method of ferric iron reduction using sodium borohydride as a reducing agent under atmospheric conditions. The obtained iron nanoparticles are mainly in zero valent oxidation state and remain without significant oxidation for weeks. A systematic characterization of nZVI was performed using UV, XR...

This minireview presents recent advances in our understanding of iron oxidation and homeostasis in acidophilic Bacteria and Archaea. These processes influence the flux of metals and nutrients in pristine and man-made acidic environments such as acid mine drainage and industrial bioleaching operations. Acidophiles are also being studied to understand life in extreme conditions and their role in ...

The systematic oxidation reactions of a wide range of alcohols have been carried out by using an iron porphyrin complex in order to understand their relation to cytochrome P-450 enzymes and to have a practical application to organic synthesis. The iron porphyrin complex catalyzed efficiently alcohol oxidation to the respective carbonyl compound via a high-valent iron-oxo porphyrin intermediate ...

Ferritins are spherical, cage-like proteins with nanocavities formed by multiple polypeptide subunits (four-helix bundles) that manage iron/oxygen chemistry. Catalytic coupling yields diferric oxo/hydroxo complexes at ferroxidase sites in maxi-ferritin subunits (24 subunits, 480 kDa; plants, animals, microorganisms). Oxidation occurs at the cavity surface of mini-ferritins/Dps proteins (12 subu...

Human ferritin H-chain mutants were obtained by engineering the recombinant protein expressed by Escherichia coli. The mutagenesis were directed to the C-terminal sequence forming the hydrophobic channel, to the hydrophilic channel and to the loop sequence. The mutants were analysed for extent of expression, for stability, for capacity to incorporate iron and for kinetics of iron uptake and iro...

The exposure of cells to several metal ions stabilizes HIF-1 alpha protein. However, the molecular mechanisms are not completely understood. They may involve inhibition of hydroxylation by either substitution of iron by metal ions or by iron oxidation in the hydroxylases. Here we provide evidence supporting the latter mechanism. We show that HIF-1 alpha stabilization in human lung epithelial ce...

Aluminum, a trivalent cation unable to undergo redox reactions, is shown to faciliate iron-initiated DOPA oxidation in the melanin pathway under acidic condition of pH 5.5, which is a favored medium for aluminum facilitation of iron-induced lipid peroxidation. In the process of oxidation of DOPA to melanin in the presence of the metal ions, Fe3+ and H2O2 oxidize DOPA to dopachrome (DC), then Al...