On the mechanism of lipoxygenase-like action of bleomycin-iron complexes.
نویسندگان
چکیده
The mechanism of lipid peroxidation catalyzed by bleomycin (BLM)-iron (Fe) complexes has been studied in vitro using sodium linoleate as a substrate. BLM-Fe(II)-O2 and BLM-Fe(III) complexes catalyze lipid peroxidation concomitantly with singlet oxygen evolution. The results from spin trapping methods and gas chromatography-mass spectroscopy (GCMS) analyses suggest that the initial step of lipid peroxidation catalyzed by BLM-Fe complexes is similar to that of soybean lipoxygenase, viz., hydrogen abstration. However, another mechanism might be concerned in the case of BLM-Fe(II)-O2 complex. BLM-Fe complexes are also capable of enhancing singlet oxygen evolution from the hydrogen peroxide (H2O2)-hypochlorite (OCl-) system.
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ورودعنوان ژورنال:
- The Journal of antibiotics
دوره 45 4 شماره
صفحات -
تاریخ انتشار 1992