Preparation of an autolysis-resistant interleukin-1-beta converting enzyme mutant

Human interleukin-1-beta converting enzyme (ICE) containing an affinity tag and modified to resist autoproteolysis was expressed, purified and characterized. The enzyme was stabilized greater than 80-fold against autolytic degradation relative to wild-type N-His ICE. An oxidized adduct of ICE with glutathione, formed by disulfide rearrangement with oxidized glutathione to inhibit and stabilize the enzyme during purification was rapidly reduced upon exposure to 5 mM dithiothreitol.