Purification of lectins by biospecific affinity chromatography.

Biospecific adsorbents which can be used for the purification of lectins are easily prepared by a one-step reaction between Epoxy-activated Sepharose 6 B and lectin-specific sugars. This paper reports the immobilization of N-acetyl-D-galactosamine and N-acetyl-D-glucosamine and the use of the resulting Sepharose derivatives for the purification of soybean lectin and wheat germ lectin, respectively. The former adsorbent had a maximal capacity of 15 mg of lectin/ml sedimented gel and the yield corresponded to 145 mg of lectin/100 g of soybeans. Similarly, yields of wheat germ lectin corresponding to 65 mg/100 g of wheat germ were obtained on an adsorbent which bound 10 mg of lectin/ml. The purified lectins were homogeneous as judged by electrophoresis in polyacrylamide gels at pH 4.5.