THE BARK LECTIN OF ROBINIA-PSEUDOACACIA - PURIFICATION AND PARTIAL CHARACTERIZATION

A lectin was purified from the bark of Robinia pseudoacacia by sequential ion-exchange chromatography on DEAE-Sepharose and CM-Toyopearl. The purified lectin was estimated to have a molecular weight of 106 kDa and to be a homotetramer of subunits with a molecular weight of 29 kDa. Antibodies raised against the bark lectin cross-reacted with a 29-kDa polypeptide during Western blot analysis, showing that the antibodies are specific for the bark lectin. The antibodies against the lectin from Robinia bark cross-reacted with polypeptides in extracts of the seeds and bark of Sophora japonica, indicating that the lectin from Robinia bark is immunologically related to the lectins of Sophora. However, the antibodies did not cross-react with proteins from Robinia seeds and leaves. The first twenty amino acid residues from the N-terminus of the lectin from Robinia bark were determined and compared with those of the Sophora lectins.