Phenoloxidase

Our current global environmental challenges include the reduction of harmful chemicals and their derivatives. Bioremediation has been a key strategy to control the massive presence of chemicals in the environment. Enzymes including the phenoloxidases, laccases and tyrosinases, are increasingly being investigated as “green products” in the removal of many chemical contaminants in waters and soils. Both phenoloxidases are widespread in nature and attractive biocatalysts due to their ability to use readily available molecular oxygen as sole cofactor for their catalytic elimination of a large number of chemicals. Taking advantage of their catalytic potentials, remarkable advances have been made in the engineering of laccases to produce suitable biocatalysts in environmental applications. Studies about novel strategies of laccase immobilization and insolubilization for the treatment of chemical contaminants were provided. Likewise, tyrosinases are gaining increasing interest in environmental applications due to their catalytic similarities with laccases although they remain far less investigated to date. This disparity was addressed in this review along with the molecular features and catalytic mechanism of tyrosinases relevant in environmental applications. A perspective on the future use of laccases and tyrosinases in bioremediation was discussed.

The presence of immune responses within sea anemone species has received little attention, in comparison with coral species, so we decided to investigate the phenoloxidase and peroxidase activities in ectoderm, endoderm and tentacles of actiniarians Aulactinia marplatensis and Bunodosoma zamponii, the most common species in intertidal zone of Mar del Plata, Argentina. Enzyme activities were detected in all tissues evaluated with some differences among tissues and species. Phenoloxidase and peroxidase activities are associated with the mechanisms of innate immunity in invertebrates, and the high production of phenoloxidase observed in B. zamponii would provide a continual level of resistance to infection and this species to be less susceptible to stress and disease, compared to A. marplatensis. This study, represents the first step toward specific immune information about the mentioned sea anemone species of Argentina, and thus permits prediction of the potential effects of environmental factors on immune response.