Fig. 1
Thrombin C-terminal peptides, and their binding to E. coli LPS. a 3D model of human α-thrombin (PDB code 1C5L) highlighting thrombin C-terminal peptide fragment. b Western blot analysis of human α-thrombin incubated with neutrophil elastase (NE) for the indicated time period generates thrombin C-terminal peptide fragments of varying lengths. The synthetic peptide HVF18 is loaded as molecular size control corresponding to generated fragments. The marker lane is from the same blot but aligned for clarity. c Table showing thrombin C-terminal peptides amino acid sequences and physicochemical properties determined using Heliquest online server tool. The hydrophobicity and amphipathicity of VFR12 was too short for accurate determination using Heliquest. d Representative intrinsic tryptophan fluorescence emission spectra of HVF18 titrated with increasing concentration of E. coli LPS. e LPS binding affinity of peptides determined from changes in emission maxima (λmax) upon titration, fitted with Graph Pad Prism v7.02 one-site binding model. Results are means ± SD of three experiments. f Ellipsometry showing peptide binding to E. coli LPS preabsorbed on solid supports. Results are means ± SD of two experiments. g Representative kinetic curves showing corresponding peptide adsorption. All experiments were performed in 10 mM Tris, pH 7.4
