Melanin is a biopolymer produced by phenol oxidases group of enzymes and plays an important role in radiational, thermal and biochemical stress tolerance. This pharmacologically active pigment has been reported to be produced by bacteria. However, there is a paucity of data for bacteria associated with melanisation in shrimp. In this context the present study was undertaken. The presence of bacteria with the extracellular phenol oxidase production from the melanized appendages of Penaeus vannamei is studied. | Study on melanized shrimp reveals bacillus sp and acinetobacter sp as potential sources for bacterial tyrosinase