The process of iron absorption has been studied in 23 patients with idiopathic haemochromatosis, in eight with iron-deficiency anaemia, and in 20 control subjects. The initial uptake of iron by the intestinal mucosa was estimated by administering (59)Fe-ferric citrate during a standard meal together with a non-absorbable marker, (51)Cr-chromic chloride. Body iron absorption (iron retained at 14...

Parameters of iron uptake have been determined for blade tissue of Macrocystis pyrifera (L.) C. Ag. These include the effects of iron concentration, light, various inhibitors, and blade type. All experiments were conducted in the defined artificial seawater Aquil. Iron uptake is light independent, energy dependent, and dependent on the reduction from Fe(3+) to Fe(2+). Iron is concentrated in th...

Ferritin was isolated from six Morris hepatomas with growth rates ranging from 3 to 12 days doubling time and also from regenerating rat liver. The ferritins from all six tumors differed electrophoretically from normal rat liver ferritin. Five of them migrated identically, and antigenic studies on four confirmed the change in protein structure. In response to iron treatment of the host, more fe...

Microbial iron uptake in the naturally fertilized waters in the vicinity of Kerguelen Islands: phytoplankton–bacteria interactions M. Fourquez, I. Obernosterer, D. M. Davies, T. W. Trull, and S. Blain Institute for Marine and Antarctic Studies, University of Tasmania, Hobart 7001, Australia Sorbonne Universités, UPMC Univ Paris 06, UMR 7621, Laboratoire d’Océanographie Microbienne (LOMIC), Obse...

Waterborne iron accumulation by the gills of the zebrafish Danio rerio was assessed in ion-poor water. Branchial iron uptake, which comprises both the iron that has entered the gill cells and iron that is strongly bound to the epithelia, has high- and low-affinity components. At low nominal [Fe] (<40 nmol l(-1)) the high-affinity component demonstrated saturation kinetics, with an apparent K(m)...

Iron is an essential element for all living organisms due to its ubiquitous role in redox and other enzymes, especially in the context of respiration and photosynthesis. The iron uptake and storage systems of terrestrial/higher plants are now reasonably well understood, with two basic strategies for iron uptake being distinguished: strategy I plants use a mechanism involving induction of Fe(III...

The uptake of iron by the absorptive cells of the duodenum, and its subsequent transfer to the lamina propria, has been studied using “Fe and high-resolution radioautography in mice rendered iron deficient by diet, in mice with dietary iron overload, and in mice with hereditary malabsorption of iron (s/a). In all, as in normally iron replete mice, two phases of iron absorption can be distinguis...

Host-pathogen interactions that alter virulence are influenced by critical nutrients such as iron. In humans, free iron is unavailable, being present only in high-affinity iron binding proteins such as transferrin. The fungal pathogen Candida albicans grows as a saprophyte on mucosal surfaces. Occasionally it invades systemically, and in this circumstance it will encounter transferrin iron. Her...

Regulation of the root high-affinity iron uptake system by whole-plant signals was investigated at the molecular level in Arabidopsis, through monitoring FRO2 and IRT1 gene expression. These two genes encode the root ferric-chelate reductase and the high-affinity iron transporter, respectively, involved in the iron deficiency-induced uptake system. Recovery from iron-deficient conditions and mo...

Iron uptake and release by ferritin molecules of different iron contents show similar profiles. These are discussed in relation to the structure of the ferritin molecule. Two models of iron uptake and release are considered. One involves iron oxidation-reduction sites on the protein. The other allows direct interaction of reagents with the iron-core crystallites. It is concluded that the second...