A mimic of superoxide dismutase activity protects Chlorella sorokiniana against the toxicity of sulfite.
The spin-trapping agent 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) has been used to demonstrate the light-dependent production of O2- by Chlorella sorokiniana. In the presence of SO3= a light-dependent production of the sulfur trioxy anion radical (SO3-.) could also be seen. A complex prepared by reacting desferrioxamine with MnO2, which catalyzes the dismutation of O2-, protected the alga against the toxicity of sulfite. The data suggest that SO2 toxicity is at least partially due to the effects of sulfoxy-free radicals generated by the oxidation of SO3= by O2-.
Rabinowitch
H D
HD
Department of Field and Vegetables, Faculty of Agriculture, Hebrew University of Jerusalem, Rehovot, Israel.
Rosen
G M
GM
Fridovich
I
I
D002708:Chlorella / Q000187:drug effects / Q000201:enzymology*; D003497:Cyclic N-Oxides; D003676:Deferoxamine; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D008027:Light; D008345:Manganese; D017895:Manganese Compounds; D010087:Oxides; D013113:Spin Labels; D013447:Sulfites / Q000378:metabolism / Q000494:pharmacology*; D013461:Sulfur Oxides / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism*; D013481:Superoxides / Q000378:metabolism
D003497:Cyclic N-Oxides; D005609:Free Radicals; D017895:Manganese Compounds; D010087:Oxides; D013113:Spin Labels; D013447:Sulfites; D013461:Sulfur Oxides; D013481:Superoxides; D008345:Manganese; C027424:manganese oxide; C017245:5,5-dimethyl-1-pyrroline-1-oxide; D013482:Superoxide Dismutase; C011118:sulfur trioxide; D003676:Deferoxamine