The mechanism of inhibition of fatty acid synthase by the herbicide diflufenican

The bleaching herbicide diflufenican (N-(2,4-difluorophenyl)-2[3-(trifluoromethyl)-3-pyridine-carboxamide) carboxamide) has been shown to inhibit plant fatty acid synthase. The mechanism of this inhibition was studied further by measuring the activities of the reductase components of the Type II fatty acid synthase complexes from Escherichia coli and avocado (Persea americana) mesocarp. Diflufenican had no effect on beta-ketoacyl-ACP reductase activity, but competitively inhibited both NADH- and NADPH-dependent enoyl-ACP reductases. This result suggests that chemicals based on the diflufenican structure may be potential herbicides by virtue of their inhibition of fatty acid synthesis.