National Center for
4AL9: Crystal Structure Of The Lectin Pa-il From Pseudomonas Aeruginoas In Complex With Melibiose
Proteins (2014) 82 p.1060-1065
The galactose-specific lectin LecA from Pseudomonas aeruginosa is a target for the development of new anti-infectious compounds. Sugar based molecules with anti-adhesive properties present great potential in the fight against bacterial infection and biofilm formation. LecA is specific for oligosaccharides with terminal alpha-galactoside residues and displays strong affinity for melibiose (alphaGal1-6Glc) with a Kd of 38.8 microM. The crystal structure of LecA/melibiose complex shows classical calcium-bridged binding of alphaGal in the primary binding site but also revealed a secondary sugar binding site with glucose bound. This sugar binding site is in close proximity to the galactose binding one, is independent of calcium and mainly involves interactions with a symmetry-related protein. This discovery would help to the design of new potent inhibitors targeting both binding sites.