Abstract
Glucose 6-phosphate dehydrogenase activity in rat liver mitochondria can be released by detergent. The released activity is separated by chromatography into two peaks. One peak has the kinetic behaviour and mobility similar to the soluble sex-linked enzyme, whereas the other peak is similar to the microsomal hexose 6-phosphate dehydrogenase. There is no evidence for the existence of a new glucose 6-phosphate dehydrogenase activity in rat liver mitochondria.