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.

Antimicrobial Activity ofCladonia verticillarisLichen Preparations on Bacteria and Fungi of Medical Importance

“…aureus than Gram-negative bacteria such as E. coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Salmonella enteritidis [17]. The difference in the susceptibility of Gram-positive and Gram-negative bacteria may be linked to the difficulty of lectins to cross the Gram-negative bacteria outer cell wall to reach the periplasmic space [15]. Additionally, the high level of peptidoglycan (which contains GlcNac) in the cell wall of Gram-positive bacteria may provide more interaction sites for N-acetyl-glucosamine-binding lectins, such as ClaveLL [10].…”

“…Lectins with potential for biotechnological applications as antibiotics have been isolated and their structures have been characterized [13][14][15]. Lectins are a heterogeneous group of proteins from no immune origin, containing two or more binding sites for mono or oligosaccharides [16].…”

Protein Purification by Affinity Chromatography

“…Guar gel beads produced by cross-linking of refined guar gum (a polysaccharide composed of glucose and mannose) with epichlorohydrin in a mixture of water and 2-propanol (Gupta et al, 1979) have been used to purify galactose-specific lectins Nunes et al, 2011).…”

<b>Antibacterial activity of different types of snake venom from the Viperidae family against <i>Staphylococcus aureus

“…Snake venoms of the family Viperidae in particular are an important source of peptides, but they remain underexplored (Ferreira et al 2011). Studies have already demonstrated that snake venoms of Bothrops jararaca (Ciscotto et al, 2009), B. leucurus (Nunes et al 2011) B. marajoensis (Costa-Torres et al, 2010), Bothrops alternatus (Bustillo et al, 2008) Crotalus adamanteus (Samy, et al, 2014), C. durissuscumanensis (Vargas et al, 2012) and Porthidium nasutum (Vargas et al, 2013) have antibacterial activity.…”