Superoxide damages dehydratases that contain catalytic [4Fe-4S](2+) clusters. Aconitases are members of that enzyme family, and previous work showed that most aconitase activity is lost when Escherichia coli is exposed to superoxide stress. More recently it was determined that E. coli synthesizes at least two isozymes of aconitase, AcnA and AcnB. Synthesis of AcnA, the less-abundant enzyme, is ...

BACKGROUND Friedreich's ataxia (FA), the most frequent form of inherited ataxias in the Caucasian population, is caused by a reduced expression of frataxin, a highly conserved protein. Model organisms have contributed greatly in the efforts to decipher the function of frataxin; however, the precise function of this protein remains elusive. Overexpression studies are a useful approach to investi...

Public concern over inadvertent kills of native birds following large-scale aerial poisoning operations for possum has highlighted deficiencies in information concerning the effects of 1080 on nontarget species. In this study biochemical and histopathological changes were measured in adult male mallard ducks (Anas platyrynchos) dosed orally with 1080. The toxin was quickly absorbed into the blo...

Beef heart aconitase, isolated under aerobic conditions, has been studied with Mössbauer and EPR spectroscopy. In the oxidized state, the enzyme exhibits an EPR signal at g = 2.01. The Mössbauer data show that this signal is associated with a 3Fe cluster. In dithionite-reduced aconitase, the 3Fe cluster, probably of the [3Fe-3S] type, is in a paramagnetic state of interger electronic spin (S = ...

There was studied the effect of high-pressure homogenization (HPH) on protein profile tiger nut “horchata” drink. were depicted samples obtained at 0, 50, 100, 150 and 200 MPa pressures by SDS-PAGE fractionation, observing no changes up to least 50 MPa. However, some alterations turned noticeable 100 reached maximum affectation level with a clear decrease in intensity 6 gel bands. LC-MS/MS anal...

This study was aimed at investigating the effects of subchronic administration of doxorubicin (DOX) on brain mitochondrial bioenergetics and oxidative status. Rats were treated with seven weekly injections of vehicle (sc, saline solution) or DOX (sc, 2 mg kg(-1)), and 1 week after the last administration of the drug the animals were sacrificed and brain mitochondrial fractions were obtained. Se...

BACKGROUND Friedreich ataxia is a neurological disease originating from an iron-sulfur cluster enzyme deficiency due to impaired iron handling in the mitochondrion, aconitase being particularly affected. As a mean to counteract disease progression, it has been suggested to chelate free mitochondrial iron. Recent years have witnessed a renewed interest in this strategy because of availability of...

Post-transcriptional regulation of mRNA translation and stability in iron metabolism involves the interaction between the trans-acting cytoplasmic iron regulatory proteins (IRP-1 and IRP-2) and cis-acting iron-responsive elements (IREs) in mRNA 5'- or 3'-untranslated regions. IRP-1 can adopt two conformations: one with a [4Fe-4S]-cluster, unable to bind IREs, which functions as a cytoplasmic ac...

The assembly of iron-sulfur (Fe-S) clusters requires dedicated protein factors inside the living cell. Striking similarities between prokaryotic and eukaryotic assembly proteins suggest that plant cells inherited two different pathways through endosymbiosis: the ISC pathway in mitochondria and the SUF pathway in plastids. Fe-S proteins are also found in the cytosol and nucleus, but little is kn...