The interaction of lactose-specific lectins with acid-treated and lactose-substituted sepharose.

The binding of two lectins, one a galactosyl/lactosyl and the other a lactosyl binding protein, to various Sepharose 4B derivatives has been investigated. The adsorbents, lactose-substituted Sepharose, acid-treated Sepharose and acid-treated, lactose-substituted Sepharose, were each tested with regard to their overall binding capacity and for the ability to separate the lectins by differential elution with solutions of galactose and lactose. The binding capacity for both lectins decreased in the order Lac-acid-Sepharose greater than Acid-Sepharose greater than Lac-Sepharose much greater than Untreated Sepharose. The ability of the gels to bind both lectins with a sufficient affinity to allow the proteins to be purified by differential elution decreased in a similar order. Acid-treated, lactose-substituted Sepharose proved the most useful gel and was utilised to isolate each lectin in a pure form.