SUBCELLULAR DISTRIBUTION OF PYRUVATE KINASE (EC 2.7.1.40) IN CEREBRAL CORTEX

Abstract

Abstract —The subcellular distribution of pyruvate kinase (EC 2.7.1.40) in the cerebral cortex of the rat was studied. The enzyme, which had been previously reported in the cytoplasm, was found to be present in synaptosomal, microsomal and mitochondrial fractions as well. The activity of the enzyme in the synaptosomal fraction was localized predominantly in the synaptosomal membrane and was not dissociated by repeated washing or recentri‐fuging in a sucrose gradient. Some kinetic parameters of the membrane‐associated pyruvate kinase were measured.