Figure 6.

TmHU exhibits an apparent decrease in occluded site size with increasing duplex length. (A) EMSA under stoichiometric conditions with 89-bp DNA and (B) the corresponding binding isotherm, in which the intercept of tangents to the saturation plateau and the initial slope reflects saturation of the DNA. (C) EMSA under stoichiometric conditions with 242-bp DNA and (D) binding isotherm reflecting saturation of 242-bp DNA by TmHU; note that all DNA still available to bind TmHU, not just unbound DNA, was considered as ‘free DNA’. For (A) and (C), complexes and free DNA are identified at the right. Protein concentrations are reflected in the corresponding binding isotherms.