Targeting bacterial biofilm: a new LecA multivalent ligand with inhibitory activity

Biofilm formation by bacterial pathogens is a hallmark of chronic infections and is associated to increased antibiotic tolerance that makes pathogens difficult to eradicate with conventional antibiotic therapies. Infections caused by Pseudomonas aeruginosa are of great concern, especially for immunocompromised and cystic fibrosis patients. P. aeruginosa lectins LecA and LecB are virulence factors and play a key role in establishing biofilm; therefore, inhibition of the function of these proteins has potential in dismantling the bacterium from the protective biofilm environment and in restoring the activity of antibiotics. Here we report the NMR characterization of the binding of a galactose-based dendrimer (Gal18) to LecA. Moreover, we demonstrate the activity of Gal18 molecule in inhibiting P. aeruginosa biofilm formation in vitro.