In the sea urchin sperm membrane has been isolated from a sugar with the egg membrane protein specificity of the protein, known as the binding protein, the molecular weight of about 30,000.

• 在海胆精子质膜上已分离到一种能与卵膜糖蛋白专一结合的蛋白质，称作结合蛋白，分子量约30000。