[Activity and molecular forms of nicotinamide adenine dinucleotide- and nicotinamide adenine dinucleotide phosphate-dependent malate dehydrogenase in bull spermatozoa].

Investigations were carried out on the activity and the isoenzyme composition of the NAD- and NADP-dependent malatedehydrogenase in the soluble and sedimental proteins of bull spermatozoa. It was found that the activity of the NAD-dependent malatedehydrogenase was higher than the activity of the NADP-dependent one both in the soluble and in the sedimental proteins. The difference in the activity was spectrophotometrically and electrophoretically demonstrated.