Two carbohydrate recognition domains of Hyphantria cunea lectin bind to bacterial lipopolysaccharides through O-specific chain

We previously identified a novel lectin cDNA from the fall webworm [Shin et al, (1998) Insect Biochem, Mel. Biol, 28, 827-837], which encodes two carb ohydrate recognition domains (CRD-N and CRD-C) and is up-regulated followin g bacterial challenge. The lipopolysaccharide (LPS) binding activities of t he recombinant CRD-N and CRD-C (rCRD-N and rCRD-C) were investigated by enz yme-linked immunosorbent assay. The LPS binding of rCRD-N and rCRD-C was pH -dependent: at pH below 6.0, they show a higher binding ability to LPS. The binding of the rCRD-N was inhibited by both D-mannose and N-acetyl-D-gluco samine, whereas the binding of the rCRD-C was inhibited only by D-mannose. The binding of both rCRD-N and rCRD-C to Escherichia coli mas mainly mediat ed through the O-specific chain. (C) 2000 Federation of European Biochemica l Societies.