identification of PAO1 specific regions. These 'chromosomal maps' display the whole PAO1 genome as a vertical strip with horizontal bands each representing a region of 1 kb at the indicated position on the chromosome with a color coded value (see color bars to the right of each map). A) Sequence similarity of PATA1 oligonucleotides and the PA14 genome. Values indicate the fraction of nucleotides that were identical in the probe oligonucleotides and the best matching alignment in PA14. B) PAO1 specific regions. The actual value indicates the fraction of DNA which is common to PAO1 and PA14 as identified in a previous ORF-by-ORF alignment . C) Signal ratio (log2) of a comparative hybridization of PA14 DNA relative to PAO1 DNA, calculated from data of single arrays for PA14 and PAO1. Values exceeding the presented interval (-3 to 0) were cut off to keep the color scale in the same range as in A) and B).