Pulchellin is a type-2 Ribosome Inactivating Protein (RIP), whose action mechanism proposed would be initiate by B-chain binding on glycoconjugate onto the cell surface (lectinic chain). pulchellin isoforms toxicity is the interaction between B-chain lectinic and the glycosyl residues on cell surface. pulchellin A chain is a novel of selective immunotoxin cytotoxicity.