Purificação parcial e avaliação do efeito aglutinante frente a bactérias patogênicas de uma lectina extraída da esponja marinha Cliona celata (Grant, 1826)

Abstract

Sponges are organisms belonging to the phylum Porifera, have a very simple general organization and are recognized for being a significant source of bioactive compounds. Lectins are characterized by being proteins or glycoproteins that have at least one non-catalytic reversible carbohydrate-binding domain, playing a fundamental role in biological processes, such as cell adhesion, cell migration, activation of the immune system and intercellular communication. Lectins from marine sponges have aroused interest due to their functional diversity, as well as their biological activities, as these proteins may have antibacterial and antimicrobial properties. These proteins enable an in-depth understanding of cellular recognition and immunity processes, which can contribute to a more detailed understanding, especially considering their high biotechnological potential. Therefore, the present work was developed with a focus on purifying, characterizing and evaluating the agglutinating effect of a lectin isolated from the marine sponge Cliona celata against pathogenic bacteria. The lectin was partially isolated from the combination of ammonium sulfate precipitation and ion exchange and molecular exclusion chromatography. The protein exhibited hemagglutinating activity against rabbit erythrocytes. The hemagglutinating activity of the C.celata extract was inhibited only by the glycoproteins asialofetuin, fetuin bovine and porcine thyroglobulin. The hemagglutinating activity of Cliona celata extract was shown to be independent of Ca+2. In SDS-PAGE, the lectin revealed a majority band of approximately 45 kDa, in addition, it was able to agglutinate bacteria from Staphylococcus epidermidis and Escherichia coli strains.