Synthase activity of isocitrate lyase from Lupinus cotyledons

This study describes a continuous optical method for assaying the synthase activity of isocitrate lyase. The enzyme used was purified from cotyledons of higher plant; also reported are some spectroscopic properties of the enzyme. Optimal conditions for the pH and the concentrations of substrates to be used in the test were studied. With the described method, there is a good proportionality between the measured activity and the concentration of the enzyme. With the method were determined the KmS for both substrates: glyoxylate and succinate. The values obtained are in close agreement with those previously reported.