[The activity of transaminases in the tissues of the Black-Sea mollusk Mytilus galloprovincialis].

The activities of aspartate aminotransferase (AST, E. C. 2.6.1.1) and alanine aminotransferase (ALT, E. C. 2.6.1.2) were studied in the tissues of the bivalve mollusks differing in shell color. Shell color patterns were assessed by photographing and computer processing in Adobe Photoshop CS-3. The activity of transaminases was determined by the Reitman-Frankel procedure. Four color groups of mollusks were singled out: black, intermediate, dark- and light brown. The AST and ALT activities were found to increase as shells lose color probably reflecting different tolerance of mollusks to habitats with different concentration of oxygen. The ALT distribution pattern differs appreciably in the foot of M. galloprovincialis where the highest values were found in the black-colored mussels, evidently due to the change of the predominant enzyme function. In this tissue, the reaction of transamination replenishes the pool of free amino acids required for the synthesis of byssus threads.