Comments |
P. R81 right column bottom paragraph: "Table 1 shows the kinetic and thermodynamic data for the folding of proteins that have been shown to fold with two-state kinetics according to the criteria above. In several cases, conditions can be found such that proteins that normally fold through a populated intermediate state can fold with two-state kinetics. Mutations that destabilise the intermediate state relative to the unfolded state can switch the kinetics from three-state to two-state, as with ubiquitin [primary source 25]. Changes in pH or temperature can have a similar effect [refs 36,37]. Some of these examples are also included in Table 1. Care needs to be taken with some of these data. A protein can only be said to fold with two-state kinetics at the minimum concentration of denaturant for which the rate of folding has been measured. Although the rate of refolding has been measured at very low concentrations of denaturant, or in the absence of denaturant for many of the proteins in Table 1, some have only been measured in moderate concentrations of denaturant, which will tend to destabilise intermediates if present. For this reason, the lowest concentration of denaturant for which folding rates have been measured, [D]min, is also given." See notes beneath table |