Fig. 6. The peripheral fraction contains a WGA-reactive high molecular weight glycoprotein that correlates with the biological activity of the ligand. (A) Biological activity of matrix and peripheral fractions before and after depletion with WGA-agarose or BS-I agarose. WGA depletes ligand activity, assayed against wild-type sperm, from both the matrix and peripheral fractions, whereas BS-I fails to deplete activity from either fraction. Each bar represents the mean±s.e.m. of triplicate assays from one experiment. The broken line indicates the number of sperm bound in the control (buffer). (B) WGA and BSI lectin blots of peripheral fraction glycoproteins. WGA reacts with high molecular weight glycoproteins in the peripheral fraction, whereas BSI does not react with any glycoprotein species. Each blot is representative of at least two experiments. Molecular weight markers are shown.