Effect of copper and zinc on the ethylene production of Arabidopsis thaliana

Abstract

The effects of toxic concentrations of the redox active metal copper and the redox inactive zinc on the ethylene production of intact, seven days old Arabidopsis thaliana (L.) Heynh. seedlings, were studied kinetically in an open flow system. Major differences in the metal stimulated increases in ethylene production were found. Using reaction rate experiments, this stimulation was shown to be entirely enzymatic in case of zinc treatment and partly enzymatic, partly non-enzymatic in case of copper addition. The existence of non-enzymatic copper stimulated ethylene production was confirmed using an oxygen-free atmosphere. By inhibiting ACC synthase activity, ACC could be indicated as the major precursor of both enzymatic and non-enzymatic copper stimulated ethylene production.