Effect of the Safener Dichlormid on Maize Peroxygenase and Lipoxygenase*
نویسنده
چکیده
S-Ethyl-N,N-dipropylthiocarbamate (EPTC) was oxidized into its corresponding sulfoxide by microsomal fractions from etiolated maize seedlings. This reaction is catalyzed by a hydroperoxide-dependent enzyme, identified as a peroxygenase. The hydroperoxides formed from fatty acids by a lipoxygenase are efficient co-substrates o f the EPTC sulfoxidation. The effects o f the safener dichlormid on the peroxygenase and lipoxygenase activities were studied in vitro and in vivo. In vitro, the safener is not an inhibitor o f these enzymes. Dichlormid seems to act, in vivo, by modulating the amounts o f peroxygenase and lipoxygenase in treated plants.
منابع مشابه
The inhibition of fatty acid elongation by pebulate can be effectively counteracted by the safener dichlormid.
The thiocarbamate herbicide pebulate inhibits fatty acid elongation, which is necessary for surface lipid biosynthesis. As both barley and wild oats are susceptible to pebulate, the safener dichlormid was used to study the reversal of its herbicidal effect. Fatty acid elongation was restored by a dichlormid pretreatment in barley, but not in pebulate-expressed oats.
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