Résumé
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.
Résumé
Of the 22 tubers and 9 pulses screened for inhibitors of enterokinase activity, the following 12 tubers, Curcuma amada, Kyllinga monocephala, Solanum tuberosum, Canna indica, Helianthus tuberosus, Coleus parviformis, Mirabilis jalapa, Colocasia antiquorum (red variety), Alium cepa, Arnorphophalus companulatus, Maranta arundinacea, Daucus carota, and 9 pulses namely, Vigna sinensis, Arachis hypogea, Pisum sativum, Phaseolus vulgaris (white bean), Phaseolus vulgaris (kidney bean), Phaseolus mungo, Cicer arietinum, Dolichos lablab and Cajonus cajan contained inhibitory activity. Three tubers, Arnorphophalus companulatus, Maranta arundinacea and Daucus carota and all the nine pulses exhibited endogenous esterase activity towards benzoyl arginine ethyl ester. Among the 8 pulses and 3 tubers processed by affinity chromatography on trypsin sepharose, to separate trypsin inhibitor from enterokinase inhibitor, Phaseolus vulgaris (kidney bean), Phaseolus vulgaris (white bean) and Dolichos lablab contained distinct enterokinase inhibitors. These fractions were devoid of trypsin inhibitor activity. The trypsin inhibitor from Coleus parviformis tubers alone did not bind to trypsinsepharose and was recovered in the unbound fraction along with the enterokinase inhibitor.