Fig. 6
From: Fine control of metal concentrations is necessary for cells to discern zinc from cobalt
Thermodynamic coupling of metal and DNA binding. Four allosteric conformations (end-states) typical of metal sensor proteins: apo-protein (P), metal-protein (P•M), apo-protein-DNA (P•D) or metal-protein-DNA ((P•M)•D). Dynafit was used to simultaneously model these coupled equilibria to determine the fractional occupancy of each operator–promoter with sensor ((P•D + (P•M)•D)/Dtotal), as a function of buffered metal concentration (Mb) (see 'Methods' section, Supplementary Data 1 and Supplementary Software). K 1−K 5 are association constants. Buffered metal was achieved by including a hypothetical buffer component (B) with defined metal affinity (1/K 5)
