Effects of Iron and Chelating Agents on Dark Carboxylation Reactions in Plant Homogenates.

Abstract
Dark fixation of CO2 in homogenates prepared from soybeans, barley, and trifoliate orange leaves with phosphoenolpyruvate, ribose-5-phosphate, and glucose-6-phosphate as substrates indicated greater activities for plants slightly Fe deficient than for plants supplied adequate iron. Chelating agents tended to increase the activities and Fe+++ added to homogenates decreased the activity. The latter was reversed by chelating agents. The inhibition with Fe was shown to be competitive.