ENZYMES INVOLVED IN DEFENSE FUNCTIONS OF HEMOCYTES OF MUSSEL MYTILUS-GALLOPROVINCIALIS

Mytilus galloprovincialis hemocytes contain phosphatases, esterases, p roteases, and glucosidases as revealed by a semiquantitative colorimet ric method. The activity levels of some enzymes changed throughout the months of the experiment without a seasonal pattern. No differences i n the enzyme levels were found between the two groups of mussels of di fferent age (cultivated 11 and 19 months on ropes hung from the same r aft). Light microscopy study of hemocyte enzymes showed that hyalinocy tes and granulocytes had reaction of acid phosphatase, beta-glucuronid ase, alpha-naphthyl butyrate esterase, naphthol AS-D chloroacetate est erase, and alpha-naphthyl acetate esterase. Phenoloxidase and peroxida se activities were also detected in monolayers of hemocytes. Ultrastru ctural study revealed that the granules of hemocytes contained acid ph osphatase, beta-glucuronidase, nonspecific esterases, peroxidase, and NADH oxidase. Products of beta-glucuronidase and peroxidase reaction w ere also localized in the plasma membrane. Lysozyme activity level was higher in hemocytes than in serum. Comparison between the two groups of different age showed a higher activity level of lysozyme in younger mussels. (C) 1997 Academic Press.