The release of iron from ferritin by aceto- and benzohydroxamic acids was studied at two different iron chelator concentrations (100 and 10 mM), at two pH values (7.4 and 5.2), and in the presence or absence of urea. Collectively, the results demonstrate that both aceto- and benzohydroxamic acids remove iron from ferritin. Aceto- and benzohydroxamic acids penetrate the ferritin shell and react ...

This study examined if complexation with metals increased the antiproliferative activities of chelators of the pyridoxal isonicotinoyl hydrazone (PIH) class. Addition of iron(III) to some PIH analogs markedly depressed their activities, whereas it had little effect on others. The gallium(III) complex of PIH, but not its copper(II) complex, was more efficient than the apochelator at inhibiting [...

High-valent iron species are known to act as powerful oxidants in both natural and synthetic systems. While biological enzymes have evolved to prevent self-oxidation by these highly reactive species, development of organic ligand frameworks that are capable of supporting a high-valent iron center remains a challenge in synthetic chemistry. We describe here the reactivity of an Fe(II) complex th...

l-norepinephrine (NE) is a neuroendocrine catecholamine that supports bacterial growth by mobilizing iron from a primary source such as holotransferrin to increase its bioavailability for cellular uptake. Iron complexes of NE resemble those of bacterial siderophores that are scavenged by human neutrophil gelatinase-associated lipocalin (NGAL) as part of the innate immune defense. Here, we show ...

Azotobacter vinelandii cydAB mutants lacking cytochrome bd lost viability in stationary phase, irrespective of temperature, but microaerobiosis or iron addition to stationary phase cultures prevented viability loss. Growth on solid medium was inhibited by a diffusible factor from neighbouring cells, and by iron chelators, In(III) or Ga(III); microaerobic growth overcame inhibition by the extrac...

Respirasomes are macromolecular assemblies of the respiratory chain complexes I, III and IV in the inner mitochondrial membrane. We determined the structure of supercomplex I1III2IV1 from bovine heart mitochondria by cryo-EM at 9 Å resolution. Most protein-protein contacts between complex I, III and IV in the membrane are mediated by supernumerary subunits. Of the two Rieske iron-sulfur cluster...

Two acridine groups were successfully introduced into di-iron(III) complex. DNA cleavage experiments indicated that complex conjugating bisacridine groups can enhance 300-fold for the cleavage efficiency compared with complex lacking of acridine conjugation. Further ligation assay of DNA segments provided the evidence for hydrolytic mechanism of DNA cleavage.

The synthesis of a range of novel 3-hydroxypyridin-4-ones and 3-hydroxypyran-4-ones linked with different coumarin substituents is described. These compounds have been developed in order to provide a series of molecular probes for the quantification of intracellular labile iron pools. An evaluation of the effect of iron(III) on fluorescence intensity was undertaken. Chelation of iron(III) cause...

Several potentially tridentate pyridyl and phenolic Schiff bases (apRen and HhapRen, respectively) were derived from the condensation reactions of 2-acetylpyridine (ap) and 2′-hydroxyacetophenone (Hhap), respectively, with N-R-ethylenediamine (RNHCH2CH2NH2, Ren; R = H, Me or Et) and com-plexed in situ with iron(II) or iron(III), as dictated by the nature of the ligand donor set, to generate the...