Studies on bioactive marine metabolites. VI. Isolation and characterization of Balanus balanoides agglutinin.

The coelomic fluid of Balanus balanoides was found to agglutinate mouse keukemia cell L5178Y and a marine bacterium Vibrio sp. in addition to various kind of animal erythrocytes. It stimulated the phagocytosis of rabbit erythrocytes by mouse macrophage. The agglutinin was purified and found to be a glycoprotein having a molecular weight of 330, 000 daltons. It contained three different subunits. The main subunits had a molecular weight of 70, 000 daltons. Isoelectro-focusing gave two bands; the main band at pI 4.7 and the minor one at pI 5.3. The hemag-glutinating activity of the purified agglutinin was inhibited by D-galacturonic acid, D-glucuronic acid and N-acetylneuraminic acid. The glycoprotein contained high amount of aspartic acid and glutamic acid, and little histidine. There was no preasence of half cystine and arginine.