Terminal anaerobic carbohydrate metabolism of three developmental stages of the rabbit stomach worm Obeliscoides cuniculi

Abstract

1. 1. The activities of phosphoenolpyruvate (PEP) carboxykinase, pyruvate kinase, lactate dehydrogenase, and malate dehydrogenase were determined for three developmental stages of the rabbit stomach worm Obeliscoides cuniculi. 2. 2. Pyruvate kinase was 18–21 times as active as PEP carboxykinase in the adult worms and 64 times as active in the free-living grd-stage larvae. 3. 3. Lactate dehydrogenase activity was low in all three stages. The fate of the pyruvate formed is therefore unaccounted for. 4. 4. The relatively high malate dehydrogenase activity detected, which reduced oxaloacetate to malate, together with the above findings suggest the possible existence of pyruvate carboxylase.