
MgCl2 dependence of 3′X55 conformational dynamics. (A) Representative 10 min transfer efficiency histograms from time-resolved measurements of 3′X55 at 50 mM MgCl2 for the time points t = 0.042, 0.167, and 0.500 days show the systematic increase in ϕint. (B) Interconversion kinetics are extracted by globally fitting the ϕ data to a kinetic model (solid lines) describing unimolecular interconversion (see Materials and Methods).










