Herein, a systematic study of a series of molecular iron model complexes has been carried out using Fe L2,3-edge X-ray absorption (XAS) and X-ray magnetic circular dichroism (XMCD) spectroscopies. This series spans iron complexes of increasing complexity, starting from ferric and ferrous tetrachlorides ([FeCl4]-/2-), to ferric and ferrous tetrathiolates ([Fe(SR)4]-/2-), to diferric and mixed-va...

Separate pathways for transport of nontransferrin ferric and ferrous iron into tissue cultured cells were demonstrated. Neither the ferric nor ferrous pathway was shared with either zinc or copper. Manganese shared the ferrous pathway but had no effect on cellular uptake of ferric iron. We postulate that ferric iron was transported into cells via beta(3)-integrin and mobilferrin (IMP), whereas ...

A heterotrophic bacterium, isolated from an acidic stream in a disused pyrite mine which contained copious growths of "acid streamers," displayed characteristics which differentiated it from previously described mesophilic acidophiles. The isolate was obligately acidophilic, with a pH range of 2.0 to 4.4 and an optimum pH of 3.0. The bacterium was unable to fix carbon dioxide but oxidized ferro...

1. When iron was available some 10 billion years ago, it was available as Fe (II), but Fe (II) is not a very strong Lewis acid. Thus, it does not bind strongly to most small molecules or activate them strongly toward reaction. 2. Today iron is not readily available from sea or water solutions due to oxidation and hydrolysis. 3. Iron in ferrous state is not easily retained by proteins since it d...

Iron deficiency and related iron deficiency anaemia (IDA) are the most prevalent nutritional disorders worldwide. The standard treatment involves supplementation with solid or liquid iron supplement preparations, usually based on a ferrous salt such as ferrous sulphate, ferrous fumarate, or ferrous gluconate. In the present study, we compared iron uptake and absorption from various solid and li...

Acid-mine drainage (AMD) is difficult and costly to treat. We investigated a new approach to AMD treatment using fuel cell technologies to generate electricity while removing iron from the water. Utilizing a recently developed microbial fuel cell architecture, we developed an acid-mine drainage fuel cell (AMD-FC) capable of abiotic electricity generation. The AMD-FC operated in fed-batch mode g...

Dps proteins, bacterial mini-ferritins that protect DNA from oxidative stress, are implicated in the survival and virulence of pathogenic bacteria. Here we examine the mechanism of E. coli Dps protection of DNA, specifically whether this DNA-binding protein can utilize DNA charge transport through the base pair π-stack to protect the genome from a distance. An intercalating ruthenium photooxida...

"Signal-on" optical detection of parts-per-billion (ppb) levels of Fe(II) in CH(2)Cl(2) and H(2)O was demonstrated using a redox-active and optically rich metal complex-based monolayer.

The antioxidant effects of meat fractions from chicken breast and beef loin were compared. Five meat fractions - homogenate (H), precipitate (P), supernatant (S), high-molecular-weight (HMW) and low-molecular-weight (LMW) fractions - were prepared from chicken breast or beef loin. Each of the fractions were added to a phospholipid liposome model system containing catalysts (metmyoglobin, ferrou...

Colloidal matrices of native and oxidized pectin were developed to improve iron bioavailability through the digestive tract. Ferrous bisglycinate (Gly-Fe), obtained by precipitation glycine chelation Fe2+, was mixed with peroxide-oxidized citrus pectin, subsequently lyophilized. Controls included without chelation. The resulting samples characterized FTIR, SEM, TGA/DSC before after in vitro dig...