Figure 7. Single-molecule properties of PBsome from mutant P. cruentum F11.

A, absorbance of ensemble PBsome from WT and mutant strain. A₅₃₂ of F11 PBS is as low as 35% than WT PBsome, so laser power performed on F11 PBsome is 700 W·cm⁻². B, fluorescence emission image of single F11 PBsome at room temperature obtained in wide-field microscopy dispersed by the Amici prism in front of CCD camera. C, single PBsome was imaged as two fluorescence bands when excited at 532 nm (black). Background is presented with light gray. Room-temperature fluorescence emission spectra of isolated mutant PBsome (0.75 M phosphate buffer, pH 7.0) were recorded when excited at 532 nm (blue). D, total intensities of PE (▴) and PBsome core (▪) emission of single PBsome as well as their ratio (□) as a function of time.