LTHOUGH many substances have been shown to increase iron ahsorption, the mechanism of this action is obscure. Fructose, for example, increases iron absorption in rats, and it has been suggested that its effect depends on its ability to chelate iron.4 We proposed to test this hypothesis, and to in ’estiga e possible relationships between the effects of various metabolic substrates and reducing a...

The Arabidopsis FRO2 gene encodes the low-iron-inducible ferric chelate reductase responsible for reduction of iron at the root surface. Here, we report that FRO2 and IRT1, the major transporter responsible for high-affinity iron uptake from the soil, are coordinately regulated at both the transcriptional and posttranscriptional levels. FRO2 and IRT1 are induced together following the impositio...

Graminaceous plant species acquire soil iron by the release of phytosiderophores and subsequent uptake of iron(III)-phytosiderophore complexes. As plant species differ in their ability for phytosiderophore hydroxylation prior to release, an electrophoretic method was set up to determine whether hydroxylation affects the net charge of iron(III)-phytosiderophore complexes, and thus chelate stabil...

The insolubility of Fe3+ necessitates special mechanisms for iron acquisition in most organisms. Bacteria use siderophores to chelate Fe3+ and iron in heme, hemoglobin, transferrin and lactoferrin, and employ novel mechanisms for receptor-dependent iron transport and iron-regulated gene expression. These mechanisms involve transfer of energy from the cytoplasmic membrane to the outer membrane t...

Different root parts with or without increased iron-reducing activities have been studied in iron-deficient and iron-sufficient control sugar beet (Beta vulgaris L. Monohil hybrid). The distal root parts of iron-deficient plants, 0 to 5 mm from the root apex, were capable to reduce Fe(III)-chelates and contained concentrations of flavins near 700 microM, two characteristics absent in the 5 to 1...

Low availability of Fe significantly limits crop yields in many parts of the world. However, it is largely unknown which genes and alleles adjust plant growth in Fe limited environments. Using natural variation of a geographically restricted panel of Arabidopsis thaliana accessions, we identify allelic variation at the FRO2 locus associated with root length under iron deficiency. We show that n...

basil (ocimum basilicum l.) belongs to the lamiaceae family as a medicinal plant used in traditional medicine in iran. the purpose of this test is to evaluate the effect of nano fe-chelate under salinity levels on the plant physiology and morphology characteristics. in this experiment  investigated the effect of nano fe-chelate and salinity stress on growth parameters, photosynthetic leaves rat...

Photosynthesis, heme biosynthesis, and Fe-S cluster assembly all take place in the chloroplast, and all require iron. Reduction of iron via a membrane-bound Fe(III) chelate reductase is required before iron transport across membranes in a variety of systems, but to date there has been no definitive genetic proof that chloroplasts have such a reduction system. Here we report that one of the eigh...

Yersinia enterocolitica commonly causes fever and mild gastroenteritis' but occasionally causes severe illness, particularly in patients with iron overload in whom its virulence is enhanced.2 Desferrioxamine used therapeutically may potentiate the growth of yersinia, which uses desferrioxamine as a siderophore to chelate iron.3 We describe three patients with transfusional haemosiderosis and in...