Thermal unfolding parameters of WT- and Opti-Pgp.

aTemperatures corresponding to the two maxima of the unfolding profiles seen in Fig. 6.bNumber of independent experiments.cAverages ± range are given.dExperiments were routinely conducted in 20 mM HEPES, pH 7.6, 50 mM NaCl, 10% glycerol, 0.1% DDM and 5.5 mM DTT. Four experiments were conducted in buffers containing 40 mM imidazole, and three experiments were conducted with reduced glycerol (5% instead of 10% glycerol); no significant differences in the Tm or ΔHcal were observed under those conditions.