| Congresso Brasileiro de Microbiologia 2023 | Resumo: 218-2 | ||||
Resumo:Lectins are proteins that presents the ability to interact with glycans and trigger varied responses, including the inhibition of the development of various pathogens. Structural studies of these proteins are essential to better understand their functions. In marine sponges, so far only a few lectins have their primary structures completely determined, and biological activity explored. Thus, the objective of this work was to structurally characterize and evaluate antibacterial potential, in association with different antibiotics, of the lectin isolated from the marine sponge Aplysina lactuta (ALL). The sponges were weighed, cut into small pieces, macerated, homogenized in Tris-HCl 50 mM, pH 8.0, containing NaCl 150 mM and L-cysteine 5 mM (TBS/Cys) at ratio 1:2 (w/v). The lectin was purified by affinity chromatography on a SepharoseTM 6B matrix. The estimation of mass by electrophoresis and size exclusion chromatography molecular showed that ALL is a homotetramer of 60 kDa formed by four 15 kDa-subunits. The lectin showed affinity only for the glycoproteins fetuin, asialofetuin, mucin type III, and bovine submaxillary mucin type I. Regarding antibacterial activity, ALL did not show antimicrobial activity against the tested strains. However, when in combination (250 and 125 µg.mL-1) with ampicillin, methicillin and tetracycline a significant increase in the antibiotics activity was observed against tStaphylococcus aureus (ATCC 25923 and ATCC 700698), Staphylococcus epidermidis (ATCC 12228 and ATCC 35984) and Escherichia coli and strains. The results of the association of ALL (125 µg.mL-1) with ampicillin and methicillin showed synergistic effect, included Methicillin-resistant Staphylococcus strains (ATCC 700698 and ATCC 35984). In addition, the association with tetracycline showed additive effect against all bacterial strains tested. Thus, ALL shows to be a protein with potential for the development of new antibacterial and/or adjuvant drugs. Palavras-chave: galectin, protein, antimicrobial, marine sponge Agência de fomento:Fundação de Amparo à Pesquisa do Estado de Minas Gerais | |||||