The article describes the studies of the iron speciation (the occurrence of Fe(II), Fe(III), and complexed iron) in acid leachable fraction of deposits. The speciation of iron was diverse for deposits of different origins and was the specific "fingerprint"-marker of deposition processes. The higher occurrence of Fe(II) may be connected with decantation which has been observed for lake sediments...

BACKGROUND The use of microencapsulated ferrous fumarate sprinkles is a new approach for home fortification. Iron and hematologic status may affect the absorption of iron from sprinkles. OBJECTIVE The objective was to measure the absorption (corrected erythrocyte incorporation of (57)Fe) of 2 different doses of iron from sprinkles added to a maize-based complementary food provided to infants ...

Decreased expression of Yfh1p in the budding yeast, Saccharomyces cerevisiae, and the orthologous human gene frataxin results in respiratory deficiency and mitochondrial iron accumulation. The absence of Yfh1p decreases mitochondrial iron export. We demonstrate that decreased expression of Nfs1p, the yeast cysteine desulfurase that plays a central role in Fe-S cluster synthesis, also results in...

The influence of iron levels on the transcription of the hupB gene in Mycobacterium tuberculosis is the focus of this study. Studies in our laboratory showed HupB to be co-expressed with the two siderophores in low-iron organisms. Mycobactin biosynthesis is repressed by the IdeR-Fe(2+) complex that binds the IdeR box in the mbtB promoter. Recently, we demonstrated the positive regulatory effect...

It has long been hypothesized that acids formed from anthropogenic pollutants and natural emissions dissolve iron (Fe) in airborne particles, enhancing the supply of bioavailable Fe to the oceans. However, field observations have yet to provide indisputable evidence to confirm this hypothesis. Single-particle chemical analysis for hundreds of individual atmospheric particles collected over the ...

The distribution of dissolved iron(II) [Fe(II)] was studied in surface waters of the western subarctic Pacific during the Subarctic Pacific Iron Experiment for Ecosystem Dynamics Study-II (SEEDS II) iron enrichment experiment using highly sensitive flow injection-based luminol chemiluminescence. Vertical profiles of Fe(II) and total dissolved iron were measured outside of the fertilized patch t...

iron oxide is an important biological agent that has a key role in medical processes; however, the mechanism whereby it provides iron for human and animal cells and its biological uses remains unclear. we aimed to evaluate the effects of oral iron oxide on serum iron status and compare the results with those of iron sulfate as a reference salt. fifteen adult rabbits were divided into 3 groups o...

Arsenic sorbs strongly to the surfaces of Fe(III) (hydr)oxides. Under aerobic conditions, oxygen acts as the terminal electron acceptor in microbial respiration and Fe(III) (hydr)oxides are highly insoluble, thus arsenic remains associated with Fe(III) (hydr)oxide phases. However, under anaerobic conditions Fe(III)-reducing microorganisms can couple the reduction of solid phase Fe(III) (hydr)ox...

The maturation of cytosolic iron-sulfur (Fe/S) proteins in mammalian cells requires components of the mitochondrial iron-sulfur cluster assembly and export machineries. Little is known about the cytosolic components that may facilitate the assembly process. Here, we identified the cytosolic soluble P-loop NTPase termed huNbp35 (also known as Nubp1) as an Fe/S protein, and we defined its role in...

Mining-impacted sediments of Lake Coeur d'Alene, Idaho, contain more than 10% metals on a dry weight basis, approximately 80% of which is iron. Since iron (hydr)oxides adsorb toxic, ore-associated elements, such as arsenic, iron (hydr)oxide reduction may in part control the mobility and bioavailability of these elements. Geochemical and microbiological data were collected to examine the ecologi...