Biological Properties of Arundo donax Lectin

VOZARI-HAMPE MM; ZANETTI, GD; DRESCH, RR; IRAZOQUI, FJ; TRINDADE, VM

Hotel Monte Real - Águas de Lindóia – SP-Brazil.

Congreso; XXXIV Reunião Anual da Sociedade Brasileira de Bioquímica e Biologia Molecular; 2005

Biological Properties of Arundo donax Lectin Vozari-Hampe M. M.1; Zanetti, G. D. 2; Dresch, R. R. 3; Irazoqui, F.J. 4; Trindade, V. M. T. 1 1Departamento de Bioquimica, Instituto de Ciencias Basicas da Saude; 2PPG-Botanica; 3PPG-Ciencias Farmaceuticas, UFRGS, Porto Alegre, RS; 4Departamento de Quimica Biologica, Facultad de Ciencias Quimicas, Universidade Nacional de Cordoba, Cordoba, Argentina The applicability of the lectins is based in the capacity of these molecules to bind in a reversible way and specifically certains carbohydrates. In this work, powdered rhizomes of Arundo donax L. (Poaceae), plant acclimated in Brazil, were used for the purification of the lectin as well as for the determination of the cytotoxic activity and chemotaxis of the isolated lectin. The proteic extract, obtained in PBS, followed by ammonium sulphate precipitation, and dialysis against purified water, was applied on immobilized rabbit erythrocytes stroma column, equilibrated with PBS. Elution of the adsorbed lectin was performed with physiologic solution and NH4OH. The active peak eluted from the stroma column was applied on N-acetyl-D-glucosamine-Agarose column and the retained lectinic fraction was desorbed with distilled water. Hemagglutinating activity was tested by the two fold serial method in microtiter U-plates using 2% native erythrocytes suspension. Proteins were evaluated by Bradford method. The isolated lectin agglutinated rabbit and pig erythrocytes with high intensity. Arundo donax lectin showed specificity towards N-acetyl-D-glucosamine, N-acetil-lactosamine, BenzylaGalNAc, BenzylaGlcNAc and BenzylbGlcNAc. The lectin cytotoxic activity was tested with Artemia salina, a crustace, and the chemotaxic activity was accomplished by the inhibition or not of the chemotaxis of neutrophyl according to Boyden (1962) method, modified by Zigmond and Hirsch (1973). The lectinic sample showed cytotoxic activity at the concentrations of 1, 10 and 100 µg/ml, with a CL50 of 0.11 µg/ml, evidencing high cytoxicity index. The chemotaxic activity of the lectin was dose not dependent, and was similar or superior to that LPS from Escherichia coli in the doses from 0,2 to 6,4 µg/ml. The results suggest that Arundo donax lectin could be an e efficient tool for cytotoxicity and chemotaxis studies. Supported by Capes/UFRGS.