The phospholipase D (PLD) fromStreptomyces chromo-fuscusbelongs to the superfamily of PLDs. All the enzymes included in this superfamily are able to catalyze both hydrolysis and transphosphatidylation activities. However, S. chromofuscusPLD is calcium dependent and is often described as an enzyme with weak transphosphatidylation activity. S. chromofuscus PLD-catalyzed hydrolysis of phospholipids in aqueous medium leads to the formation of phosphatidic acid.