Desialylation of glycoconjugates using immobilized vibrio cholerae neuraminidase. Preparation, properties and use of the bound enzyme.

Neuraminidase from Vibrio cholerae was immobilized on Sepharose 4B using the cyanogen bromide technique. The properties of the bound enzyme were found to be similar to those of the soluble form, except for an appreciably improved stability on storage at equivalent dilution and a reduction in recovered activity. Evidence was obtained that the binding of large molecular weight substrates to the bound enzyme is modified due to the immobilized state of the enzyme. The use of the enzyme gel for desialylation of glycoconjugates in a closed circuit system was investigated and optimal conditions delineated using fetuin as a model substrate. The bound enzyme could be used repeatedly with only low loss of activity. The value of the desialylation circuit in the preparation of partially and completely desialylated glycoconjugates is discussed. The use of immobilized neuraminidase for the desialylation of cells is described.