IMMUNOGENICITY OF THE N-GLYCANS OF PEANUT PEROXIDASE

The three tryptic glycopeptides of cationic peanut peroxidase (C. PRX) and the sole one of anionic peanut peroxidase (A. PRX) were individua lly coupled to bovine serum albumin to raise antisera. The three categ ories of antibodies directed towards three N-glycans of C. PRX (anti-G La, anti-GLb and anti-GLc) were isolated from antisera with glycan-con jugated ECH Sepharose 4B affinity columns and the distribution of epit opes on the N-glycans was investigated. The reactivity of anti-GLa, an ti-GLb and anti-GLc is inhibited 25-40% by 1 M fucose, compared with a slight inhibition by N-acetylglycosamine and xylose. Mannose and gala ctose showed no inhibition to anti-GLa and only a slight inhibition to anti-GLb and anti-GLc. All of anti-GLa, anti-GLb and anti-GLc recogni ze A. PRX and horseradish peroxidase but do not recognize fetuin. Also , their reactivity is inhibited by bromelain by more than 70%. The thr ee categories of antibodies present high homogeneity and appear to be directed mainly towards the core structure [Xyl] (Man)(3) [Fuc] (GlcNA c)(2). An effective and simple method to screen antibodies with carboh ydrate specificities is described herein.