FIG. 4.
TNS analysis of toxin B hydrophobicity following pH shift. TNS was added to toxin B at pH 4.0 and incubated for 20 min at 37°C, and the emission profile was determined. The pH was then raised to pH 7.0, and the TNS emission spectrum was generated. The spectra represent TNS-toxin B fluorescence after subtraction of background (TNS plus buffer alone). Similar relative fluorescence was obtained in two consecutive repetitions of this experiment.