Abstract
The glycan-binding profile of a β-galactoside-binding 15 kDa lectin (Galectin-1) purified from the oocytes of the American bullfrog, Rana catesbeiana, was studied using 61 pyridyl-aminated oligosaccharides by frontal affinity chromatography. Human blood type-A-hexasaccharide (GalNAcα1-3(Fucα1-2)Galβ1-4GlcNAcβ1-4Galβ1-4Glc) was found to exhibit the strongest ligand binding to the galectin while Forssman antigen (GalNAcα1-3GalNAcβ1-3Galα1- 4Galβ1-4Glc) and type-A-tetrasaccharide (GalNAcα1-3(Fucα1-2)Galβ1-4GlcNAcβ1-4Glc) were also extensively recognized. The kinetics of affinity of galectin-1 to type-A oligosaccharide was analysed by surface plasmon resonance using neoglycoprotein with type-A oligosaccharides. R. catesbeiana oocyte galectin adhered to human rhabdomyosarcoma cells dose dependently and the activity was specifically cancelled by the neoglycoprotein. It was concluded that galectin-1 from R. catesbeiana oocytes possesses different and rare glycan-binding properties from typical members in galectin family.
Keywords: American bullfrog (Rana catesbeiana), blood type-A hexasaccharide, cell adhesion activity, frontal affinity chromatography, galectin-1