Properties and Specificity of a Second Metal Chelator-sensitive Proteinase in the Keratinolytic Larvae of the Webbing Clothes Moth

Abstract

The properties of a second metal chelator-sensitive proteinase (metalloproteinase 2) from the larvae of the webbing clothes moth, Tineola bisselliella, have been studied. The pH optimum for casein digestion was 9�4 and the enzyme showed high stability between pH 8 and 11, but very poor stability at acid pH. The proteinase was inhibited by EDTA, but not by an EDTA-calcium complex. EDTA inhibition could be reversed by addition of a slight excess of calcium or zinc ions. The cleavage specificity of metalloproteinase 2 against the A and B chains of S-carboxymethyl insulin was almost identical to that found previously for metalloproteinase 1.