Lactate dehydrogenase--X--separation of human spermatozoa isoenzymes by extraction with detergents

Proteins with known enzymatic properties are attractive molecules as possible agents for immunological contraception. Therefore a new technique for the selective isolation of LDH-X from human spermatozoa is described. Applying the detergents hyamine 2389 and triton X-100 LDH-X is extracted from the sperm surface membrane without the other LDH-isoenzymes. Ultrasonification of spermatozoa yields all LDH-isoenzymes together. After cell disruption the separation of LDH-X and the isoenzymes is performed by discelectrophoresis. With lactate as substrate tetrazolium staining identifies all LDH-enzymes. The technique represents an attractive method for the selective isolation of LDH-X and opens further purification steps.