AFM imaging of IRR-OrfAB[1-149] complexes. (A) Images obtained for a 250 bp DNA fragment carrying a right inverted repeat (IRR), with or without incubation with OrfAB[1-149]. (B) Examples of structures observed between OrfAB[1-149] and DNA. DNA is represented as in figures 2-4 as large cylinders (IRR) and small cylinders (flanking DNA). The different structures are: pX = parallel X; pY = parallel Y; Ap = anti-parallel (see text). The Number (n) and percentage of these complexes are given. (C) Organisation of the DNA fragment is represented with theoretical lengths: Ltot is the total length and Lse is the length from the end of the DNA fragment to the OrfAB[1-149] binding site within IRR (Figure 1c).