Surface Plasmon Resonance Assay

Surface plasmon resonance studies were performed as described previously [43 (link)]. Amine coupling was used to ligate either HD6 or flagellin to individual flow cells on a CM5 sensor chip. The running buffer (pH 7.4) contained: 10 mM HEPES, 150 mM NaCl, 3 mM EDTA, and surfactant P20 (0.005%). The multi-cycle experiments were performed with an analyte flow rate of 20 μl/min for 12.5 min in each cycle. This was followed by a 2.5 min interval during which the flow cells were perfused by analyte-free buffer until the sample loop had acquired the next 250 μl aliquot of analyte solution. The final analyte injection was in "kinetic mode", with a 10 min dissociation period.