CHEMICAL COMPOSITION OF THE ACROSOMES OF RAM SPERMATOZOA

Abstract

Summary. Material extracted from ram spermatozoa with 0·0125 n-NaOH was separated into lipid and glycoprotein fractions. By use of an anionic detergent (Hyamine 2389) acrosomes were separated from ram spermatozoa and also fractionated into lipid and glycoprotein. The chemical compositions of the two glycoprotein fractions, as well as of the two lipid fractions, show marked similarities. Taking into consideration the chemical changes that may occur during the isolation of these fractions it is deduced that they provide a reasonable approximation to the composition of the acrosomes. Of the amino acids glutamic acid predominates. The following sugars are present: mannose, galactose, fucose, glucosamine, galactosamine and sialic acid. The residue left after extracting ram spermatozoa with n-NaOH contains polysaccharide of which the constituent sugars are glucose, galactose and mannose. All the sialic acid of ram spermatozoa appears to be contained in the acrosome. The sialic acid content of the spermatozoa of other species has been measured and the possible role of sialic acid in sperm physiology is discussed.