Oxygen species characterization

Monooxygenases, 25 382, 383 reactions effected by, 25 383 Mono-oxygen species, characterization, 32 111-112... 

Characterization of the oxidized and reduced catalyst surfaces and the active oxygen species. 

Epe, B., Pflaum, M., Haring, M., Hegler, J. and Rudiger, H. (1993). Use of repair endonucleases to characterize DNA damage induced by reactive oxygen species in cellular systems. Toxicol. Lett. 67, 57-72. 

Colquhoun and Schumacher [98] have shown that y-linolcnic acid and eicosapentaenoic acid, which inhibit Walker tumor growth in vivo, decreased proliferation and apoptotic index in these cells. Development of apoptosis was characterized by the enhancement of the formation of reactive oxygen species and products of lipid peroxidation and was accompanied by a decrease in the activities of mitochondrial complexes I, III, and IV, and the release of cytochrome c and caspase 3-like activation of DNA fragmentation. Earlier, a similar apoptotic mechanism of antitumor activity has been shown for the flavonoid quercetin [99], Kamp et al. [100] suggested that the asbestos-induced apoptosis in alveolar epithelial cells was mediated by iron-derived oxygen species, although authors did not hypothesize about the nature of these species (hydroxyl radicals, hydrogen peroxide, or iron complexes ). 

In a recent paper a detailed mechanistic study of this reaction was presented (108). The first step is the reversible binding of oxygen by forming a u-peroxo species. This intermediate reacts further via an irreversible step to the hydroxylated product. The kinetic measurements at high pressure were performed at -20°C, since at room temperature no peroxo intermediate can be observed. The forward reaction of the Cu(I) complex with oxygen is characterized by a strongly... 

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