Fig. 1

Analysis of the A. baumannii pan-genome. The distribution of protein cluster sizes generated from the comparison of 249 A. baumannii genomes using PanOCT [35] indicates the number of singleton and core genes (a). The pan-genome size (left panel) and the number of novel genes discovered with the addition of each new genome (right panel) were estimated for all 249 genomes (b) and a set of 100 representative genomes identified by hierarchical clustering of all 249 genomes (c) using a pan-genome model based on the original Tettelin et al. model [42]. Purple circles are the median of each distribution (gray circles). Power law (red lines) and exponential (blue lines) regressions were plotted to determine α (open/closed status) and tg(θ), the average extrapolated number of strain-specific/novel genes, respectively [41]