A morphogenic enzyme was a type of enzyme present in changelings. these enzymes were responsible for their shapeshifting and telepathic abilities. These enzymes could be tested with a morphogenic enzyme analysis. (DS9: "When It Rains...")
In 2373, Dr. Julian Bashir found residual traces of these enzymes in a neurochemical scan of a supposedly solid Odo's brain after they had been activated by a plasma storm. (DS9: "Things Past")