Papain Membrane on a Collodion Matrix: Preparation and Enzymic Behavior

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Science  05 Nov 1965:
Vol. 150, Issue 3697, pp. 758-760
DOI: 10.1126/science.150.3697.758


A stable papain membrane has been prepared on a collodion matrix by absorbing papain in a collodion membrane and then cross-linking the papain with bisdiazobenzidine 3,3'-disulfonic acid. The pH-dependence of the activity of the enzyme membrane on the low-molecular-weight substrate, benzoylarginine ethyl ester, was found to differ from that of crystalline papain; the activity was low in the neutral pH range where the native enzyme has its optimum and high at alkaline pH. This anomalous behavior is due to a lowering of the local pH within the membrane as a result of the release of acid by the enzymic hydrolysis of the ester substrate.