Oxidation superoxide

Beckman, J.S. and Crow, J.P. 1993. Pathological implications of nitric oxide, superoxide and peroxynitrite formation. Biochem. Soc. Trans. 21 330-334. 

In addition to nitric oxide, superoxide, and peroxynitrite, NO synthases are able to generate secondary free radicals because similar to cytochrome P-450 reductase, the reductase domain can transfer an electron from the heme to a xenobiotic. Thus it has been found [158,159] that neuronal NO synthase NOS I catalyzed the formation of CH3CH(OH) radical from ethanol. It was suggested that the perferryl complex of NOS I is responsible for the formation of such secondary radicals. Miller [160] also demonstrated that 1,3-dinitrobenzene mediated the formation of superoxide by nNOS. It was proposed that the enhancement of superoxide production in the presence of 1,3-dinitrobenzene converted nNOS into peroxynitrite-produced synthase and may be a mechanism of neurotoxicity of certain nitro compounds. 

Skulachev [117] proposed that the released cytochrome c oxidizes superoxide and, by this, exhibits an antioxidant function. This proposal was supported by recent experimental findings by Atlante et al. [118], who suggested that cytochrome c released from mitochondria by oxygen species protected mitochondria through a feedback-like process oxidizing superoxide. The most important physiological inhibitor of apoptosis is multifunctional protein Bcl-2,... 

It has been shown that lung macrophages from patients with systemic sclerosis (SS) produced the elevated levels of nitric oxide, superoxide, and peroxynitrite and expressed the enhanced level of iNOS [281], NAC administration reduced peroxynitrite production and might be possibly recommended for the treatment SS patients. Solans et al. [282] found the significant enhancement of lipid peroxidation in erythrocytes from SS patients. Cracowski et al. [283] showed that in vivo lipid peroxidation was enhanced in scleroderma spectrum disorders including SS and undifferentiated connective tissue disease. 

Further reduction of H2O2 yields the hydroxyl radical, OH, indeed a powerful but indiscriminant and very unstable oxidant. Superoxide anion may itself serve as the reductant of H2O2 to form OH in the presence of ionic iron in a reaction called the Haber-Weiss reaction... 

As would be expected, several additional applications of cryoprobe technology in the area of biomacromolecular NMR were also published. Goger et al,253 described the reduction in time required for the acquisition of triple resonance NMR experiments performed on proteins. Later in the year, Craik et al.254 reported a study of the 21 amino acid bacterial peptide microcin J25 that relied on cryoprobe technology. In late 2003, Bertini and co-workers255 reported the application of cryoprobe-based 13C direct-detection NMR experiments on a paramagnetic oxidized superoxide dismutase. 

Beckman IS, Koppenol WH (1996) Nitric oxide, superoxide, and peroxynitrite the good, the bad, and ugly. Am J Physiol 271 C1424—C1437... 

Das UN. Long-chain polyunsaturated fatty acids interact with nitric oxide.superoxide anion, and transforming growth factor-fl to prevent human essential hypertension. Eur. J. Clin. Nutr. 2004 58 195-203. 

Saldeen, T.. Li, D., and Mehta, J. L. (1999) Differential effects of alpha- and gamma-tocopherol on low-density lipoprotein oxidation, superoxide activity, platelet aggregation and arterial thrombogenesis. J Am Coll Cardiol 34, 1208-15. 

The oxidized form of superoxide reductase formed in this reaction is reduced back by rubredoxin, dependent ultimately on reduced pyridine nucleotides via intermediate electron carriers [65]. The reaction of SOR with superoxide is also very fast, the reaction rate constant being of an order of 10 M s. It has been demonstrated that CuZnSOD can also function as superoxide reductase reducing superoxide at the expense of oxidation of ferrocyanide, or as superoxide oxidase, oxidizing superoxide at the expense of reducing ferricyanide [66]. Both ferri- and ferrocyanide are unphysiological substrates but the enzyme can also act as superoxide reductase with nitroxyl anion oxidizing it to nitric oxide [67]. 

Scheme V. Reaction of 5,5-dimethyl-l-pyrrolidine-N-oxide superoxide ion in the presence of a proton source to give radical hydroperoxide 10. ...

Bonfoco E, Krainc D, Ankarcrona M, Nicotera P, Lipton SA (1995) Apoptosis and necrosis two distinct events induced respectively by mild and intense insults with NMDA or nitric oxide/superoxide in cortical cell cultures. Proc Natl Acad Sci USA 92 72162-72166... 

Crow, J.P. and J.S. Beckman (1995). Reactions between nitric oxide, superoxide, and peroxynitrite Footprints of peroxynitrite in vivo. Adv. Pharmacol. 34, 17—43. 

Reactions between Nitric Oxide, Superoxide, and Peroxynitrite Footprints of Peroxynitrite in Vivo... 

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