title: Purification of a lectin with antibacterial activity from Bothrops leucurus snake venom.
abstract: A novel lectin was isolated from Bothrops leucurus snake venom using a combination of affinity and gel filtration chromatographies. The lectin (BlL) agglutinated glutaraldehyde-treated rabbit and human erythrocytes with preference for rabbit erythrocytes. Galactose, raffinose, lactose, fetal bovine serum and casein inhibited lectin-induced rabbit erythrocyte agglutination. BlL, with a molecular mass of 30 kDa and composed of two subunits of 15 kDa, showed dependence on calcium. BlL is an acidic protein with highest activity over the pH range of 4.0-7.0 and stable under heating to 70°C. Fluorescence emission spectra showed tryptophan residues partially buried within the lectin structure. The percentages of secondary structure revealed by circular dichroism were 1% α-helix, 44% β-sheet, 24% β-turn and 31% unordered. BlL showed effective antibacterial activity against Gram-positive bacteria Staphylococcus aureus, Enterococcus faecalis and Bacillus subtilis with minimal inhibitory concentrations of 31.25, 62.25 and 125 μg/mL, respectively. In conclusion, B. leucurus snake venom contains a galactoside-binding lectin with antibacterial activity.
authors.affiliation: Departamento de Bioquímica, Universidade Federal de Pernambuco, Avenida Professor Moraes Rêgo s/n, Cidade Universitária, Recife, Pernambuco, Brazil.
authors.forename: Erika dos Santos
authors.initials: Edos S
authors.lastname: Nunes
authors.forename: Mary Angela Aranda
authors.initials: MA
authors.lastname: de Souza
authors.forename: Antônio Fernando de Melo
authors.initials: AF
authors.lastname: Vaz
authors.forename: Giselly Maria de Sá
authors.initials: GM
authors.lastname: Santana
authors.forename: Francis Soares
authors.initials: FS
authors.lastname: Gomes
authors.forename: Luana Cassandra Breitenbach Barroso
authors.initials: LC
authors.lastname: Coelho
authors.forename: Patrícia Maria Guedes
authors.initials: PM
authors.lastname: Paiva
authors.forename: Rejane Maria Lira
authors.initials: RM
authors.lastname: da Silva
authors.forename: Rosemeire Aparecida
authors.initials: RA
authors.lastname: Silva-Lucca
authors.forename: Maria Luiza Vilela
authors.initials: ML
authors.lastname: Oliva
authors.forename: Miriam Camargo
authors.initials: MC
authors.lastname: Guarnieri
authors.forename: Maria Tereza dos Santos
authors.initials: MT
authors.lastname: Correia
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D017837:Bothrops; D003435:Crotalid Venoms / Q000737:chemistry*; D037161:Galectins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D006801:Humans; D011817:Rabbits
chemical_list: D000900:Anti-Bacterial Agents; D003435:Crotalid Venoms; D037161:Galectins