Feather keratin as a ligand in an affinity chromatographic technique for isolation of protease from Trichophyton verrucosum.

A technique of affinity chromatography was developed and optimized for proteases from the postculture fluid of Trichophyton verrucosum. The technique employs porous glass with adsorbed feather keratin or keratin covalently bound to the glass. Modifications of the amounts of proteases introduced into the columns and the manner of elution (pH gradient, buffer concentration, EDTA) made it possible to achieve yields of the isolated enzymes of the order of 80%. The degree of purification of four fractions isolated by the proposed technique was about 6-fold and allowed electrophoretically almost homogeneous enzymatic forms to be isolated. Substrate and inhibition tests on the four chromatographically purified proteolytic enzymes indicated a specifically keratinolytic nature of the enzymes studied.