FIGURE 6.

Effect of solution pH on ligand release from variant sLDLR. One μg of AEDANS-Trp-null apoE3-NT·DMPC and 4 μg of a given sLDLR were incubated in 10 mm Tris base, 2 mm CaCl₂, 100 mm NaCl, pH 7.0. At time 30 s, the solution pH was changed by adding an aliquot (6 μl) of 1 m Tris succinate, pH = 6.0. Samples (300 μl final volume) were excited at 280 nm, and fluorescence emission intensity at 470 nm was monitored as a function of time.