Fig. 5
Binding affinities of the selected clones. a SPR sensorgams obtained by single-cycle kinetics of tandem PDZ domains (analyte) against immobilized biotinylated Xph15/18/20 (ligand). The reported concentrations represent the highest concentration used on the final analyte injection, the previous four injections are a series of twofold dilutions. The immobilized ligand density for Xph15, Xph18 and Xph20 was 37, 74 and 24 RU, respectively. For each experiment, the theoretical Rmax (maximum analyte-binding capacity of the surface in RU) was compared to the experimental Rmax (theory/observed: 23/20 RU, 47/52 RU and 15/17 RU for Xph15, Xph18 and Xph20, respectively). The coloured curves represent measured data points and black lines represent the global fit obtained with a 1:1 binding model used for analysis. Kinetics values are the average and s.d. of three independent titrations. For rate plane with isoaffinity diagonals representation, see Supplementary Fig. 24. b Isothermal titration calorimetry thermographs and curve fits for titrations of Xph15, 18 and 20 into PSD-95 domains 1 and 2. N represents the fitted stoichiometry. Source data are provided as Source Data file
