Superoxide dismutases are a family of metalloenzymes that catalyze the dismutation of superoxide radicals into molecular oxygen and hydrogen peroxide, and thus represent a primary line of defence against oxidative stress. The iron-containing superoxide dismutases are only found in prokaryotes and plants. The iron superoxide dismutase of Vigna unguiculata (cowpea) consists of two polypeptides of...

A novel, strictly anaerobic, cadaverine-oxidizing, defined coculture was isolated from an anoxic freshwater sediment sample. The coculture oxidized cadaverine (1,5-diaminopentane) with sulfate as the electron acceptor. The sulfate-reducing partner could be replaced by a hydrogenotrophic methanogenic partner. The defined coculture fermented cadaverine to acetate, butyrate, and glutarate plus sul...

Reactive oxygen species (ROS) include a wide variety of molecules and free radicals derived from molecular oxygen. O2 being highly electrophilic can be reduced by one electron at a time producing relatively stable intermediates, such as superoxide anion (O2• ̄), precursor of most ROS and a relevant mediator in many biological reactions. Dismutation of O2• ̄ produces hydrogen peroxide (H2O2), whic...

SOD2 (EC 1.15.1.1), a metalloenzyme that catalyzes the disproportionation ofsuperoxide radicals to molecular oxygen and hydrogen peroxide, is important in cellular defense against oxygen toxicity (reviewed in ref. 5). In pea (Pisum sativum L.) leaf, three forms of the enzyme exist, all ofwhich are nuclear encoded and catalyze the same dismutation reaction. The Cu/Zn SOD is the predominant form ...

Cu,Zn-superoxide dismutase (Cu,Zn-SOD) is a ubiquitous enzyme with an essential role in antioxidant defense. To better understand structural factors at the origin of the highly efficient superoxide dismutation mechanism, we analyzed the consequence of copper reduction on the electronic properties of the backbone and individual amino acids by using electrochemistry coupled to Fourier transform i...

Formaldehyde is the illegal chemical substance used for food preservation in fish and vegetable. It can promote carcinogenesis. Superoxide dismutases are the important antioxidative enzymes that catalyze the dismutation of superoxide anion into oxygen and hydrogen peroxide. The resultant level of oxidative stress in formaldehyde-treated lymphocytes was investigated. The formaldehyde concentrati...

The antibiotic bongkrekic acid is shown to inhibit the phosphorylation of added ADP coupled with either the reactions of the respiratory chain or the dismutation of oc-ketoglutarate in mammalian mitochondria. It also prevents the utilization of ATP for energy-linked cation transport and in energy dissipation by uncoupling agents. However, bongkrekic acid does not inhibit the Mg++-requiring ATPa...

Cu/Zn-superoxide dismutase (Cu/Zn-SOD) is an enzyme that is ubiquitously present in the cytoplasm and causes dismutation of superoxide radicals, therefore Cu/Zn-SOD is primarily used as an antioxidant marker. Levels of Cu/Zn-SOD are higher in the serum of hemodialysis patients than in serum of healthy volunteers. The increase of serum Cu/Zn-SOD levels is related to the decrease of kidney functi...

Superoxide dismutases (SODs) are enzymes that protect against oxidative stress by dismutation of superoxide into oxygen and hydrogen peroxide through cyclic reduction and oxidation of the active-site metal. The complete enzymatic mechanisms of SODs are unknown since data on the positions of hydrogen are limited. Here, methods are presented for large crystal growth and neutron data collection of...

Previous studies had demonstrated that Furacin (5-nitro-2-furaldehyde semicarbazone) inhibited the dismutation of pyruvate as well as its conversion to acetylmethylcarbinol by cell-free extracts of both avian (1) and bacterial (2) cells. It was therefore thought desirable to investigate the effect of this compound on the so called phosphoroclastic dissimilation of pyruvate to acetyl phosphate a...