Figure 2

OrfAB[1-149] binds right inverted repeat (IRR) (36 bp) as a dimer. (A) EMSA analysis of the binding of OrfAB[1-149] (dark circle) to a 36 bp IRR without any flanking DNA (grey cylinder). Radiolabeled IRR containing DNA fragments (5 nM) were incubated with increasing amounts of OrfAB[1-149] (0.06, 0.125, 0.25 and 0.5 μM). Reactions were separated in 5% native polyacrylamide gels (12 V cm) and only one complex (I) is visualised. (B) EMSA analysis of the binding of OrfAB[1-149] (dark ball) and TrxA-OrfAB[1-149] (dark ball with a tag) to a 36 bp IRR without any flanking DNA (grey cylinder). Radiolabeled IRR containing DNA fragments (5 nM) were incubated with OrfAB[1-149] and/or TrxA- OrfAB[1-149] (the final protein concentration is 125 nM in lanes 2-4). Reactions were separated on 5% native polyacrylamide gels (12 Vcm-1) and complexes I, II and III are visualised. A model for complexes stoichiometry and molecular weight is proposed. (C) The panel represents a plot of the migration (mm) of the complexes in the gel as a function of the logarithm of their theoretical molecular weight as proposed in A.