DNA Walk Map. DNA Walk is a vectorial representation of DNA sequences transformed into a planar trajectory, visualised by drawing the trajectory of nucleotides moved upwards for A, downwards for T, to the right for G, and to the left for C. (A) DNA Walk of Clostridium perfringens, which exhibits strong AT/GC skew and therefore produces an extremely linear V-shaped graph, whose vertices correspond to the replication origin and terminus. (B) DNA Walk of Gloeobacter violaceus, where no GC skew is observable. Large regions of asymmetric nucleotide compositions resulting in large hairpin-like structures can be observed. (C) Close-up of region around the yfg operon in Escherichia coli, where a large hairpin-like structure about 50 kilobases long can be observed.