CGL, a Lectin from Crenomytilus grayanus, Exhibits Antibiofilm and Synergistic Antibacterial Activity Against Escherichia coli and Staphylococcus aureus

Lectins are carbohydrate-binding proteins that specifically bind to sugar groups associated with other molecules. Several studies have reported that these proteins can also modulate the activity of antibiotics against multidrug-resistant (MDR) strains in addition to interacting with carbohydrates. This study reports that gentamicin exhibits enhanced antibacterial activity against <i>Escherichia coli</i> (Gram-negative) and <i>Staphylococcus aureus</i> (Gram-positive) bacterial strains when complexed with <i>Crenomytilus grayanus</i> lectin (CGL). Enzyme-linked lectin, thermofluor, and isothermal titration calorimetry assays revealed that gentamicin interacts with CGL through a domain distinct from the carbohydrate recognition domain. An increase in antibacterial activity was observed when lectin and antibiotic were used together against <i>S. aureus</i> in living systems-specifically, sea urchin (<i>Strongylocentrotus nudus</i>) embryos.