Interactions of concanavalin a with a trimannosyl oligosaccharide fragment of complex and high mannose type glycopeptides

It has previously been reported that the binding interactions of concanavalin A with a purified high mannose type glycopeptide from ovalbumin differs from that with simple mono- and oligosaccharides (Brewer, C.F. (1979) Biochem. Biophys. Res. Commun. 90, 117-122). We now report studies with a synthetic analog of complex type glycopeptides, and a synthetic trimannosyl oligosaccharides fragment that is common to both complex and high mannose type glycopeptides. We find that both synthetic oligosaccharides undergo similar interactions with concanavalin A which mimic the effects of binding corresponding larger glycopeptides. Furthermore, the relative affinity of the trimannosyl oligosaccharides is 130-fold greater than the binding of methyl-α-D-mannopyranoside. The results indicate that the trimannosyl oligosaccharide is a unique structural element recognized by the lectin. © 1985 Academic Press, Inc.