Figure 3.
Small molecule catalysts are active over a broad pH range. The rate of fluorescent peptide binding (change in initial rate in mP/min) was determined in the presence of the small molecules J10 or J10-1 (both at 100 μM), DM (50 nM) or a solvent control (DMSO) using MBP-488 as a probe for DR15 (DR15/CLIP as input) and HA-488 as a probe for DR1 and DR4 (DR1/CLIP and DR4/CLIP as input complexes). The concentrations of DR/peptide complexes and fluorescent peptides were as reported in Figure 2. Reactions were performed in a 100 mM citric acid/phosphate buffer system adjusted to the indicated pH. Due to the slow binding kinetics of HA-488 to DR1 and DR4 only curves with DM and J10-1 are shown for these allotypes.