Isolation and new biological properties of Arion empiricorum lectin

The lectin present in the mucus of the snail Arion empiricorum was isolated by ion exchange chromatography. Purity was demonstrated by immunelectrophoretic analysis, immunization studies, and polyacrylamide gel electrophoresis. With the latter we found a molecular weight of 43,000. Hemagglutination inhibition studies revealed that carbohydrates play a minor role in the agglutination reaction of A. empiricorum lectin. Stronger inhibition could be achieved with human serum and the serum of several animal species. These findings were clarified by the demonstration that some serum proteins were precipitated by A. empiricorum lectin. Besides its agglutinating and precipitating properties the purified A. empiricorum lectin possesses proteinase-inhibiting properties, as demonstrated by the inhibition of casein-digestion by trypsin and plasmin.