FIG 2.
Thermostability of CpkA and its variants. Each sample contained 50 μg ml−1 of chaperonin dissolved in 25 mM Tris-HCl (pH 7.8) containing 300 mM KCl. Sample denaturation was monitored by measuring the change in absorption at 222 nm at temperatures from 30°C to 100°C. Data for each sample were plotted after subtracting data obtained at the indicated temperatures. The denaturation of CpkA is indicated by black dots in each frame, whereas that of mutants is indicated by white dots. (A) CpkA-E530G. (B) CpkA-E530M. (C) CpkA-Q533G. (D) CpkA-Q533M. (E) CpkA-P538G. (F) CpkA-P538M. (G) CpkA-D545G. (H) CpkA-D545M.