Inhibition of the enzyme phosphoenolpyruvate-carboxylase (PEPC) by different pollutants.

The inhibitory effect of different pollutants on the enzyme phosphoenolpyruvate-carboxylase was investigated. For this enzyme, different procedures are described for determining the activity of the enzyme. Determination of the presence of the enzymatically-formed oxaloacetate was found to be more suitable for this purpose because of the higher sensitivity compared with that of the enzymatically-formed phosphate. In order to detect possible inhibitors of this enzyme, inhibition tests were carried out with different pesticides and metal ions. The enzyme activity was decreased by ziram, ferbam and pentachlorophenol. Of the tested metal ions, the enzyme reacts very sensitively to mercury ions, however cobalt, lead, zinc and copper also showed an inhibition effect.