Fig. 9.

Competition between SCPI and NBD-Ch for binding to isolated SCP-2. A: Fluorescence emission spectra of 1.25 µM NBD-Ch in the presence of 5 µM recombinant SCP-2 and SCPI-1 in increasing concentrations from 0 µM to 10 µM [traces (a)-(f)]. Traces (g) and (h) represent NBD-Ch alone and SCP-2 alone, respectively. All final reaction mixtures contained 0.25% (v/v) dimethylformamide, the solvent used for NBD-Ch and the SCPIs. B: Fluorescence peaks from A and from a similar experiment using 0–10 µM SCPI-3 were integrated, and the level of NBD-Ch fluorescence relative to that in the absence of SCPI was plotted against SCPI concentration. Values are means ± SD (n = 4).