Bacterial Expression of Rhamnose-Binding Lectin from Catfish Eggs

SUEL-like lectins, also termed rhamnose-binding lectins (RBL), are unique in animal lectin families because of their tandemly repeated structure that is characteristic of carbohydrate-recognition domains, as well as their α-galactoside-binding capacity. RBLs are known to be expressed in inclusion bodies in Escherichia coli. Here, we describe the methods for the expression and refolding of Silurus asotus lectin (SAL) using E. coli KRX as the host strain. From our results, highly basic and reduced conditions due to arginine and dithiothreitol, respectively, tend to keep SAL recombinants soluble.