FIGURE 9.

Disaggregation of LPS by Pa4. A, FITC-LPS disaggregation by Pa4 using fluorescence spectroscopy. The fluorescence intensity of FITC increases as a function of increasing concentrations (0.1–15 μm) of Pa4 peptide. Fluorescence studies were performed in 10 mm sodium phosphate buffer, pH 6.0, at 298 K. B, particle size measurements of LPS in free and in the presence of Pa4 from quasi-elastic light scattering measurements. The average size of aggregates of LPS (top) was observed to decrease upon addition of Pa4 in a 1:2 molar ratio (bottom) in 10 mm sodium phosphate, pH 6.0, at 298 K. C, one-dimensional ³¹P NMR spectra of 0.2 mm LPS in the presence of different concentrations of Pa4, showing the changes of chemical shift (arrow) as well as the line broadening of ³¹P resonances (▼) of LPS. The NMR experiments were carried out in aqueous solutions, pH 4.5, on a Bruker DRX 400-MHz spectrometer, pH 4.5.