Rational protein design is an emerging approach for testing general theories of protein chemistry through the creation of new structures and functions. Here we present the first successful introduction by rational design of a [Fe4S4] cuboidal cluster into the hydrophobic core of Escherichia coli thioredoxin, a protein normally devoid of metal centers. Cuboidal [Fe4S4] is one of the stable forms...

Results from different experimental systems demonstrate that increased oxidative damage plays a role in normal aging and age-associated pathology. In the current study, long-term cultures of hippocampal neurons were examined as a model system. It was established that neuronal survival in long-term culture decreases according to the Gompertz law and that neuronal "aging in the dish" is associate...

The suicide inactivation mechanism of tyrosinase acting on its substrates has been studied. The kinetic analysis of the proposed mechanism during the transition phase provides explicit analytical expressions for the concentrations of o-quinone against time. The electronic, steric and hydrophobic effects of the substrates influence the enzymatic reaction, increasing the catalytic speed by three ...

Plant defense response is an elaborate biochemical process shown to depend on the plant genetic background and on the biological stressor. This work evaluated the soybean biochemical foliar response to brown stink bug herbivory injury through an analysis of redox metabolism and proteomic 2DE profiles of susceptible (BRS Silvania RR) and resistant (IAC-100) varieties. The activity of lipoxygenas...

Obesity increases the risk of arterial hypertension in young adults and favors an early-onset cardiomyopathy by generating oxidative stress. In this sense, indiscriminate consumption sucrose fructose sweetened beverages from early ages causes obesity, however its consequences on heart when there is a genetic predisposition to develop are not clear. We compared effects sucrose, fructose, their c...

Several inherited disorders of fatty acid beta-oxidation have been described that relate mainly to saturated precursors. This study is the first report of an enzyme defect related only to unsaturated fatty acid oxidation and provides the first in vivo evidence that fat oxidation in humans proceeds by the reductase-dependent pathway. The patient was a black female, presenting in the neonatal per...

Carcinogenic activation of polycyclic aromatic hydrocarbons (PAH) involves two main pathways: one-electron oxidation and monooxygenation. One-electron oxidation produces PAH radical cations, which can react with cellular nucleophiles. Results from biochemical and biological experiments indicate that only PAH with ionization potentials below ca. 7.35 eV can be metabolically activated by one-elec...

Bacterial oxidation of Mn(II) to Mn(IV) is believed to drive the oxidative segment of the global biogeochemical Mn cycle and regulates the concentration of dissolved Mn(II) in the oceanic water column, where it is a critical nutrient for planktonic primary productivity. Mn(II) oxidizing activity is expressed by numerous phylogenetically diverse bacteria and fungi, suggesting that it plays a fun...

Transient receptor potential vanilloid 1 (TRPV1) channel is a tetrameric protein that acts as a sensor for noxious stimuli such as heat and for diverse inflammatory mediators such as oxidative stress to mediate nociception in a subset of sensory neurons. In TRPV1 oxidation sensing, cysteine (Cys) oxidation has been considered as the principle mechanism; however, its biochemical basis remains el...

The effects of sonication, potassium ferrate (K2FeO4) oxidation and their simultaneous combination (called “sono-oxidative pre-treatment”) on chemical properties and anaerobic digestion of waste activated sludge (WAS) were investigated and compared comprehensively. Based on chemical parameters, the optimum operating conditions were found to be 0.3 g K2FeO4/g total solids (TS) dosage for 2-h ind...