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.