Secretory Expression and Characterization of Chinese Narcissus GNA-Like Lectin in Pichia pastoris

Narcissus tazetta lectin (NTL) is a GNA-like lectin, which has a wide potential application in medicine, agriculture, and glycobiology. In the present paper, the codon-optimized ntl gene was transformed into the yeast Pichia pastoris; SDS–PAGE gel and western blotting analysis revealed that the recombinant lectin was expressed successfully in Pichia yeast. The similarity between the recombinant NTL and the native NTL was confirmed by circular dichroism (CD) and hemagglutination assay further. In the 5-L scale fermentator, the protein yield was as high as 1.2 g/L after fermentation for 96 h. In addition, the effect of metal ions (K⁺, Mg²⁺, Ca²⁺, and Cu²⁺), acid, and alkaline on hemagglutinating activity of NTL was tested, which provided biochemical characterizations of the mannose-binding lectin from Chinese Narcissus.