Eggshell membrane is a mechanically stable and insoluble cross-linked fibrous protein. strain ME-4 synthesizes a metalloprotease that degrades the eggshell membrane. We cloned the encoding gene in . The recombinant protease, over-expressed in , was inactive but addition of acetone to crude cell extracts restored the activity and removed many proteins. We purified the active, acetone-treated protease to homogeneity in a single chromatography step with 57% recovery. The recombinant protease partially hydrolyzed eggshell membrane and produced more soluble peptides and proteins than commercial elastase, alpha-chymotrypsin, and collagenase. The soluble peptides produced from hydrolyzed eggshell membrane inhibited angiotensin-I-converting enzyme activity. The degradation of eggshell membrane by the recombinant elastase could be applied to the production of soluble bioactive peptides.