Fig. 9

Interaction between pseudonajide and LTA. The Klotz plot of the fluorescence polarization vs LTA concentration indicates the interaction between FITC-pseudonajide and LTA. Measurements were recorded in water for a FITC-pseudonajide constant concentration of 5 μM and LTA monomer concentrations corresponding to 0.5, 1, 5, 10, 50, 100, 500 and 1000 M equivalents. Titration series were set in triplicates. Data points arrange along with a sigmoid. Fitting according to a 1:1 model discloses a mid-titration corresponding to a Kd in the range of 47-51 μM. The sharper and steeper rise of the sigmoid is evocative of a cooperative binding process