HEMAGGLUTINATING ACTIVITY AND STRUCTURAL STABILITY OF A SNAIL EGG-PROTEIN

ITUARTE, S; DREÓN, MS; HERAS, H

Potrero de Los Funes, SL

Congreso; XLVII Reunión Anual de la Sociedad Argentina de Investigaciones Bioquímicas; 2011

Sociedad Argentina de Investigaciones Bioquímicas

Many glycan binding proteins have been isolated from mollusks,where they function as recognition and immune molecules. Herewe report the hemagglutinating activity of scalarin (SC), an eggprotein from the aquatic snail Pomacea scalaris, and characterizethis activity in the context of the structural stability of the protein.Two biological functions, found in proteins of a related species,were assayed: trypsin inhibition and hemagglutinating activity. SCdid not inhibit trypsin but showed high agglutinating activityagainst rabbit red blood cells. Hemagglutination was not altered bythe presence of divalent cations and it was strongly inhibited byglucosamine, galactosamine and GalNAc. SC was resistant topepsin and trypsin digestion. Temperature and pH stability,analyzed by fluorescence and visible spectroscopy, indicated that itwas stable up to 60°C; in coincidence with a loss ofhemagglutinating activity above this temperature. While SC didnot show structural perturbations between pH 2.0 and 10.0, a loss inactivity was observed below pH 4.0 and above pH 8.0.These results strongly suggest that SC has the potential ofbecoming a biotechnologically useful lectin, due to its wide pH andtemperature stability range. This is the first report of a proteaseresistantglycan binding protein in a Pomacea snail, a genus wherenovel egg-defense systems were recently described.