Serrapeptase – also known as serrapeptidase, serratiopeptidase and serratia peptidase – is a powerful proteolytic enzyme derived from a species of bacteria originally found in the intestine of silkworms. The bacterium, Serratia marcescens, produces the enzyme serrapeptase to enable the silkworm to dissolve its silken cocoon and emerge as a moth after metamorphosis. Serratia is now grown in cultures to produce serrapeptase by fermentation, and it is suitable for vegetarians.