- Localization and structural characterization of an oligosaccharide O-linked to bovine PDC-109. Quantitation of the glycoprotein in seminal plasma and on the surface of ejaculated and capacitated spermatozoa. Calvete, J.J., Raida, M., Sanz, L., Wempe, F., Scheit, K.H., Romero, A., Töpfer-Petersen, E. FEBS Lett. (1994)