Abstract
A water soluble lipoprotein with a molecular weight of ten million was isolated from sea urchin eggs. It contained 28.5% protein, 65.2% lipid, and 5.8% carbohydrate. No protein-bound P was present. The neutral carbohydrate was mannose. An analysis of the classes of lipid and the overall fatty acid composition was performed. The amino acid composition of the protein was determined. The results indicate that this lipoprotein closely resembles the low density lipoprotein of mammalian plasma.