FIGURE 3.

Comparative screening of the Ac-SKG-Pya-N₁-X-Nop-GGK-CONH₂ peptide libraries. Either ECE-1 (white) or ECE-2 (black) at 1 μg/ml was incubated at 37 °C for 3 h with 100 μm of each peptide library in a final volume of 100 μl of 100 mm HEPES, pH 6.8, or 200 mm sodium acetate, pH 5.5, respectively. Control base fluorescence was measured by incubating the peptide library alone in 100 μl of its reaction buffer. The histogram shows the deltas of fluorescence, which correspond to the fluorescence of the assay minus that of the base fluorescence of the library at 180 min.