www.tjprc.org editor@tjprc.org A PHYSICO-CHEMICAL CHARACTERIZATION OF A NATURAL AGGLUTININ FROM THE MUCUS OF A SLUG LAEVICAULIS ALTE (FERUSSAC, 1822) SR MR BASIL-ROSE 1 , A. PUNITHA 1 , A. ARUL GANDHI 2 , R. VISWAMBARI DEVI 3 & C. JOSEPHINE PRIYATHARSHINI 1 1 Research Scholar, Department of Zoology, Holy Cross College (Autonomous), Nagercoil, India 2 Enzene Biosciences Ltd Biotechnology Pune, Maharashtra, India 3 Bioengineering and Drug design Lab, Department of Biotechnology, Indian Institute of Technology, Chennai, India ABSTRACT Natural hemagglutinin, which is highly specific for the glycocalyx of rabbit erythrocytes is identified in the gastropodanmollusc Laevicaulisalte. Of the tissues/fluids of the said species tested for hemagglutination activity, maximum hemagglutin ability is observed in the mucus. Physico–chemical characterization of the mucus agglutinin of L. alte shows optimum agglutinability at pH 7.5 and temperature 55 ° C. Agglutinability is altered by the inclusion of diverse concentrations of cations or chelators in the buffer. The agglutinability is lost fully, when the mucus is pre- adsorbed with any one erythrocyte that is recognized by the agglutinin. The hemagglutinability of the agglutinin with rabbit erythrocytes is inhibited by the glycoproteins fetuin, α acid glycoprotein, bovine submaxillary mucin, lactoferrin, apotransferrin and the sugars maltose, N-acetyl neuraminic acid, lactose and galactose. Decline in hemagglutination activity when mixed with the asialo rabbit erythrocytes and reduction in hemagglutination inhibition titer when treated with desialylated fetuin, α acid glycoprotein, bovine submaxillary mucin, and lactoferrin reveals the affinity of L. alte mucus agglutinin to sialic acid. KEYWORDS: Lectin, Mucus Agglutinin, Erythrocytes, Hemagglutination Assay & Hemagglutination Inhibition Assay Received: Aug 04, 2018; Accepted: Aug 24, 2018; Published: Sep 14, 2018; Paper Id.: IJZROCT20182 INTRODUCTION Inventions of newlectins have endowed greater insight into the multiplicity and intricacy of lectin repertoires in invertebrates. Lectins are multivalent carbohydrate-binding proteins with the ability to agglutinate erythrocytes, bacteria and other normal and malignant cells displaying more than one saccharide of sufficient complementarity (Barondes, 1981). C- typelectins from molluscs have attracted much attention for their great diversity in structure and activity, and they also provide a model system to understand the molecular basis of how proteins recognize carbohydrates. Because of the wide variety of sugar specificities, C-type lectins are implicated as the indispensable candidates in carbohydrate recognition, capable of discriminating various correlative microbes and in developing biochemical tools. Lectins react with sugars in glycolipids, glycoproteins, or oligosaccharides and agglutinate erythrocytes via cell surface glycoproteins and glycolipids (Stromberg et al., 1991; Sharon, 2008). Their specificity is usually defined in terms of monosaccharide(s) or simple oligosaccharides that inhibit lectin-induced agglutination (Sharon Original Article International Journal of Zoology and Research (IJZR) ISSN (P): 2278-8816; ISSN (E): 2278-8824 Vol. 8, Issue 3, Oct 2018, 11-22 © TJPRC Pvt. Ltd.