Effect of BSO-supplemented heavy metals on antioxidant enzymes in Arabidopsis thaliana.
Activities of the ascorbate-glutathione cycle enzymes were investigated in leaves of Arabidopsis thaliana plants grown for 7 and 14 days in modified Hoagland nutrient solution containing Cd and Cu alone or supplemented with buthionine sulfoximine (BSO), an inhibitor of glutathione synthesis. In A. thaliana treated with Cd+BSO, the modifying BSO effect involved dehydroascorbate reductase (DHAR) activity after 7 days of treatment and ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR) and glutathione reductase (GR) activities after 14 days. DHAR activity increased, while activities of APX, MDHAR and GR decreased in comparison to that found with Cd alone. BSO supplied in combination with Cu modified the metal effect on APX activity after 7 days of exposure and on MDHAR activity after 14 days. Cu+BSO enhanced APX activity, but decreased MDHAR activity as compared to that with Cu alone. Similarities and varieties in the modifying BSO effect, depending on the metal, have been discussed. The modifying BSO effect was more pronounced in the plants exposed to Cd than Cu, and was opposite after 7 and 14 days. However, differences between the effects of the individual metals on the enzymes were greater after 7 days of plant exposure.
Drazkiewicz
Maria
M
Department of Plant Physiology, Maria Curie-SkŁodowska University, Akademicka 19, 20-033 Lublin, Poland. maria.drazkiewicz@poczta.umcs.lublin.pl
Skórzyńska-Polit
Ewa
E
Krupa
Zbigniew
Z
D000975:Antioxidants / Q000378:metabolism*; D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development; D060387:Ascorbate Peroxidases; D019328:Buthionine Sulfoximine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005980:Glutathione Reductase / Q000378:metabolism; D019216:Metals, Heavy / Q000633:toxicity*; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D010088:Oxidoreductases / Q000378:metabolism; D010544:Peroxidases / Q000378:metabolism; D012989:Soil Pollutants / Q000633:toxicity*; D013997:Time Factors
D000975:Antioxidants; D019216:Metals, Heavy; D012989:Soil Pollutants; D019328:Buthionine Sulfoximine; D010088:Oxidoreductases; D010544:Peroxidases; D060387:Ascorbate Peroxidases; D009247:NADH, NADPH Oxidoreductases; C023927:monodehydroascorbate reductase (NADH); D005980:Glutathione Reductase; C020666:glutathione dehydrogenase (ascorbate)