Un- and refolding kinetics of CMPK wt – Chevron Plot and end point analysis.

Data was collected with a photomultiplier and 360(a) Apparent rate constants λ as a function of urea concentration. The slow unfolding (•) and refolding (○) transitions show a linear dependency in the semi-logarithmic plot. The fast refolding transition (□) shows an increasing rate constant towards intermediate urea concentrations and therefore suggests to be associated with an intermediate state. (b) Amplitudes of the observed kinetic traces. While the slow transitions show constant amplitudes (symbols like in (a)), the amplitude of the fast transition decreases and turns negative at 2.0 M urea. (c) End-point analysis of the unfolding and refolding transitions. Filled symbols represent unfolding transitions from 0.6 M urea, while open symbols depict refolding transitions from 6.0 M urea. Start (•) and end (▪) values are taken from extrapolation (t = 0 s and t = ∞ s) of the fit results (single exponential for unfolding, double exponential for refolding) of primary data (see Fig. 3). As guide to the eye, the dotted line indicates the extrapolation of signal intensity in the unfolded state. The dashed line represents the signal intensity of the first datapoints and therefore indicates the amplitude difference associated with the burst phase. The apparent differences in data quality concerning signal to noise ratio originate from different sampling times for individual time windows (see Methods).