Affinity chromatography of invertase on concanavalin A-bead cellulose matrix: the case of an extraordinary strong binding glycoenzyme.

This work presents confirmation of the biospecific character of the interaction of Concanavalin A (Con A) immobilized on bead cellulose with invertase. In spite of the extraordinary strong binding of invertase to this Con A conjugate (KD = 5 x 10(-9) M), conditions have been found to use Con A-bead cellulose as an affinity chromatography medium. The effective factor in the release of the bound invertase by the counter ligand (alpha-methyl-D-mannopyranoside) is the time of incubation. This phenomenon was demonstrated in both batch and flow-through experiments. A concentration of 1.5 mg Con A per ml of gel was found to be suitable with regard to the maximal invertase/Con A binding ratio and the optimal invertase recovery (94%). As a result of the strong biospecific interaction the purification of invertase was very effective (above ten-fold). Verification by FPLC and PAGE of the product purity revealed only one significant protein band.