Nucleic acid colinearity of EC1 vs. Ech1591 (A), 3937 (B), Ech586 (C), Ech703 (D), ZJU1202 (E) and DZ2Q (F), respectively. The sequence of EC1 is ordered according to that of the reference bacterium based on Mummer 3.22 (http://mummer.sourceforge.net/). Then upper and following axes of linear synteny graph are constructed after the same proportion of size reduction in length of both sequences (parameter: b, 200; c, 65; extend: l, 20). According to BLAST results, each pair nucleic acid sequence of two alignments is marked in the coordinate diagram according to its position information after the same proportion of size reduction. Orange lines connecting homologous regions present in the same orientation while the blues present inverted orientation.