The present work describes the intrachloroplast localization and the changes that took place in the thylakoid and stroma-located superoxide dismutases (SOD, EC 1.15.1.1) and ascorbate peroxidases (APX, EC 1.11.1.11), in response to long-term NaCl stress in Pisum sativum L. cv. Puget plants. Native PAGE using high chloroplast protein concentrations pointed to the presence of the two main Fe-SODs...

Both Fe deficiency and Cd exposure induce rapid changes in the S nutritional requirement of plants. The aim of this work was to characterize the strategies adopted by plants to cope with both Fe deficiency (release of phytosiderophores) and Cd contamination [production of glutathione (GSH) and phytochelatins] when grown under conditions of limited S supply. Experiments were performed in hydropo...

N-bridged diiron tetra-tert-butylphthalocyanine activates H(2)O(2) to form anionic hydroperoxo complex [(Pc)Fe(IV)=N-Fe(III)(Pc)-OOH](-) prone to heterolytic cleavage of O-O bond with the release of OH(-) and formation of neutral diiron oxo phthalocyanine cation radical complex, PcFe(IV)=N-Fe(IV)(Pc(+)˙)=O. ESI-MS data showed stability of the Fe-N-Fe binuclear structure upon formation of this s...

The Haft Saravan area is located in 90 km SE Arak in the central Iran. This area is a part of Malyer-Isfahan metallogenic belt. The article's objective is determining the most suitable method for identifying mineralized zones using original singularity and weighted singularity methods in three-dimensional space. In weighted singularity method, mineralized zones have a greater volume relative to...

A chromatographic method was developed for simultaneous determination of Fe(III), Fe(II), Mn(II), and other transition metals. A high-performance polymer-coated silica-based cation exchange column was used for the separation of metals from hydrochloric acid-extracted environmental samples. After separation, the metals were mixed with PAR [4-(2-pyridylazo)resorcinol] and passed through a superco...

 Herein we report, the robustness of UV/H2O2/Fe2+ system for efficient decolorization of azo-dye Acid Yellow (AY17) solution. It has been found that 88% AY17 decolorized by UV/H2O2/Fe2+ system in 25 minutes under the following optimized conditions; [dye] = 0.14 mM, [H2O2] =1.0 mM, [Fe<s...

High-valent iron species are powerful oxidizing agents in chemical and biological catalysis. The best characterized form of an Fe(V) equivalent described in biological systems is the combination of a b-type heme with Fe(IV)=O and a porphyrin or amino acid cation radical (termed Compound I). This work describes an alternative natural mechanism to store two oxidizing equivalents above the ferric ...

Previous studies using cell and whole embryo cultures have shown that free radicals play an important role in the ethanol-induced death of mouse neural crest cells (NCCs; a significant cell type with respect to the genesis of alcohol-related birth defects). This investigation was spurred by reports of increased iron in ethanol-exposed fetuses and the knowledge that iron can initiate the product...

Experiments have been carried out with field-grown pear trees to investigate the effect of iron chlorosis on the composition of the leaf apoplast. Iron deficiency was associated with an increase in the leaf apoplastic pH from the control values of 5.5-5.9 to 6.5-6.6, as judged from direct pH measurements in apoplastic fluid obtained by centrifugation and fluorescence of leaves incubated with 5-...

Microorganisms have been observed to oxidize Fe(II) at neutral pH under anoxic and microoxic conditions. While most of the mixotrophic nitrate-reducing Fe(II)-oxidizing bacteria become encrusted with Fe(III)-rich minerals, photoautotrophic and microaerophilic Fe(II) oxidizers avoid cell encrustation. The Fe(II) oxidation mechanisms and the reasons for encrustation remain largely unresolved. Her...