The heparin-binding domains at LG4 and LG5 are targeted by P. aeruginosa laminin-binding proteins. Schematic cartoon of laminin-111 with the alpha (α, medium grey), beta (β, light grey) and gamma (γ, dark grey) subunits forming a cross-shaped molecule (a). The five laminin globular (LG) domains at the base of the molecule are coloured (green, LG1-3; orange, LG4; and yellow, LG5). Heparin-binding sites are denoted with line and asterisks (* = hep-1, ** = hep-2 and *** = hep-3)16. Interactions between the bacterial receptors and laminin were found to be inhibited by preincubation with increasing concentrations of heparin. This indicated the involvement of HBDs (b). Truncated fragments of LG (LG1-3, LG4 and LG5) were recombinantly expressed and the interactions with the P. aeruginosa receptors were analyzed by ELISA using rabbit pAbs for each bacterial receptor (c). In negative controls (Neg. ctrl.), the ligands were omitted. All results are presented as the mean values from three independent repetitions. Error bars represent standard deviation of the data.