A- Native gel showing the complexes formed by PspF1-275 WT (5 μM) ± σ54 (1 μM) ± RNA polymerase (0.15 μM) in the presence of AlFx reactant (AlC3 (0.4 mM) + NaF (5 mM)) and different nucleotides (4 mM, as indicated). The sample was loaded onto native PAGE 4.5% and proteins were detected by Coomassie Blue staining. ANP indicates AMP or ADP.
B- Gel filtration profiles of samples containing PspF1–275 WT (64 μM) ± σ54 (30 μM) ± AMP-AlFx or ADP-AlFx (as indicated) chromatographed through a Superdex 200 column (10×300 mm, 24 ml, GE Healthcare) at 4 °C. The scale bars give the scale of the ordinate axis; absorption units (AU) correspond to an A280nm of 1.