[Carboxylic proteinase from Trichoderma lignorum].

A carboxylic proteinase has been isolated from a commercial preparation of Trichoderma lignorum used as a source of cellulolytic enzymes. The purification procedure included precipitation by (NH4)2SO4 (65% saturation), gel-filtration through Acrylex P-10, affinity chromatography on gramicidin S bound to an inorganic matrix, gel-filtration through Acrylex P-10, affinity chromatography on bacitracin-Sepharose and separation on Ultrogel AcA 54 followed by gel-filtration through Sephadex G-50. A 400-fold purification of enzyme was achieved, the enzyme yield being 7,2%. The molecular weight of carboxylic proteinase as determined by gel-filtration is 33 000; its amino acid composition is found to be similar to that of carboxylic proteinases isolated from other fungal species. The enzyme is stable within the pH range of 3,0-6,0. The enzyme was fully inhibited by the specific inhibitors of carboxyliec proteinases-N-diazoacetyl-N'-2,4-dinitrophenylethylenediamine and pepstatin.