Sickle erythrocytes have increased ferritin and increased molecular iron on the inner membrane leaflet, and we postulated that cytosolic labile iron is also elevated. We used the fluorescent metallosensor, calcein, and a permeant Fe2+ chelator to estimate labile cytoslic Fe2+, and calcein plus an Fe3+ chelator to estimate total cytosolic labile iron (Fe2+ + Fe3+). We measured membrane nonheme i...

We are addressing the puzzling metal ion specificity of Fe- and Mn-containing superoxide dismutases (SODs) [see C.K.Vance, A.-F. Miller. J. Am. Chem. Soc. 120(3) (1998) 461-467]. Here, we test the significance to activity and active site integrity of the Gln side chain at the center of the active site hydrogen bond network. We have generated a mutant of MnSOD with the active site Gln in the loc...

Extensive use of nanoparticles (NPs) in consumer and industrial products has led to concerns about their potential environmental impacts; however, the influences of different NPs (e.g., nZVI (nano zero-valent iron), Ag NPs, Fe2O3 NPs and MgO NPs) on the anaerobic digestion of sludge have not yet been studied in depth. Additionally, a new guideline or the use of different NPs in the anaerobic di...

BACKGROUND Mitochondrial oxidative stress is a contributing factor in the etiology of numerous neuronal disorders. However, the precise mechanism(s) by which mitochondrial reactive oxygen species (ROS) modify cellular targets to induce the death of neurons remains unknown. The goal of this study was to determine if oxidative inactivation of mitochondrial aconitase (m-aconitase) resulted in the ...

Metal nanoparticles (NPs) are of great interest due to their special optical, [ 1–3 ] electronic, [ 4–8 ] and catalytic [ 9,10 ] properties. [ 11 ] Among metal NPs, Au NPs have been investigated most extensively because of their facile preparation, resistance to oxidation, and surface plasmon resonance (SPR) band that can absorb and scatter visible light. [ 3 ] Core/ shell and alloy bimetallic ...

background: sensitive and glucantime (ma) resistance leishmania tropica are referred to those isolates, which are responsive, or non-responsive to one or two full courses of treatment by ma systematically and/or intra-lesionally, respectively. in this study, we evaluated the antileishmanial activity of biogenic selenium nanoparticles (se nps) alone and in combination with ma against sensitive a...

Ten chromite ores from ophiolite complexes in SE Iran were analyzed mineralogically by XRD, chemically by XRF, and mineral chemistry by EPMA. The identified paragenesis of silicate minerals of chromite ores with the X-ray diffraction is pronounced differently. It consists of secondary phases formed as serpentine, Cr-containing chlorite (kaemmererite), chromic garnet (uarovite) with preserved pa...

The divalent metal-isocitrate site of pig heart NADP-specific isocitrate dehydrogenase can be located by affinity cleavage of the enzyme by Fe(2+)-isocitrate in the presence of O2, in analogy to the "chemical nuclease" action of DNA-binding drugs linked to Fe-EDTA. The enzyme is irreversibly inactivated and cleaved by Fe(2+)-isocitrate more rapidly than by Fe2+. Mn2+ prevents inactivation and c...

Analysis of RNA isolated from Pseudomonas aeruginosa PA103 and PAKS grown under Fe2+-limiting (0.08 microgram/ml) and Fe2+-sufficient (10 micrograms/ml) conditions demonstrated that exotoxin A (ETA) expression is regulated by Fe2+ at the level of transcription. S1 nuclease mapping revealed two 5' termini of the tox transcript, 89 base pairs (bp) (S1A) and 62 bp (S1B) 5' to the ETA initiation co...