Phenoloxidase System of the Blowfly, Calliphora erythrocephala

Abstract
In Calliphora larvae, an inactive precursor of the enzyme phenoloxidase is present in the hemolymph. A special activator enzyme is localized in the cuticle. When phenoloxidase precursor is allowed to react with the activator, it yields a soluble enzyme having the characteristics mainly of a diphenoloxidase. If, however, this conversion takes place in the presence of mitochondria, the phenoloxidase becomes bound to the mitochondria and the resulting preparation shows equally mono- and diphenoloxidase activity.