Figure 2.
Example titration of ZTP riboswitch with ZMP. (a) Raw data prior to baseline correction and (b) data after baseline correction for a binding isotherm of 20 μM Fusobacterium ulcerans ZTP riboswitch titrated with 200 μM ZMP at 37 °C, as corrected by and viewed in NITPIC [14]. (c) Fit of binding isotherm prior to SEC purification and (d) of a separate titration after SEC purification of the peak corresponding to the monomeric RNA. Note the shift in the x-value of the inflection point (indicated by dashed lines) from (c) to (d) indicating the change in the fraction competent for binding. For (c), the incompetent fraction was ~45%. The first two points in each titration were excluded.