Purification of bovine and porcine enterokinase by affinity chromatography with immobilized kidney bean enterokinase inhibitor.

A specific enterokinase inhibitor isolated from kidney bean (Phaseolus vulgaris) was immobilized on Affigel-10. Solubilized preparation of bovine and porcine enterokinases were bound to this matrix at pH 7·5 and the complex was dissociated by elution with l0 mM HCl, resulting in the isolation of the enzymes in homogeneous form as judged by gel chromatography on Sephadex G-200, and sodium dodecyl sulphate-polyacrylamide gel electrophoresis. However, human enterokinase could not be purified by this method in sufficient yield since it did not bind strongly to the insolubilized inhibitor.