MEROPS family M49 contains dipeptidyl-peptidase III, a widely-distributed soluble, cytosolic and membrane-localized enzyme that is probably a housekeeping peptidase important for the catabolism of intracellular peptides. The D. melanogaster enzyme has been shown to plays a major role in the degradation of the myotropic neuropeptide proctolin. (Adapted from FBrf0160783 and FBrf0239469.)