Partial Purification of the Sperm-binding Factor from the Egg of the Sea Urchin, Anthocidaris Crassispina, Followed by an Immunological Method. (sperm-binding factor/sea urchin egg/Fab fragments/neutralizing activity/purification)

Abstract

Univalent antibody (Fab fragments) against sperm-binding factor inhibits the fertilization of eggs species-specifically. The sperm-binding factor was partially purified from unfertilized eggs of the sea urchin A. crassispina by monitoring its neutralizing effect on fertilization inhibiting Fab fragments. It formed 2 species-specific precipitin lines by the double-immunodiffusion test and gave 3 main bands of protein with apparent MW of 80,000, 87,000 and 225,000, on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Carbohydrate was detected in the 1st and 3rd of these protein bands.