Figure 5.

Urea-dependent activation of Adk. The k_cat for Adk catalysis at indicated urea concentrations (and saturating ADP concentrations). The dashed and solid lines, respectively, indicate fits of measured activities to model 1 (in which activity is scaled with global Adk unfolding) and model 2 (in which activity is scaled with global unfolding and a kinetic activation term). The activation m value (m_act) and $k_{\text{cat}}^{{\text{H}}_2\text{O}}$ value from the fit to model 2 were 0.51 kJ mol⁻¹ M and 297 s⁻¹, respectively. The error represents the SD from triplicate measurements.