Fig. 1

A pangenome analysis of the global 109 Citrobacter species strains, including the four Citrobacter isolates, highlighted by means of high font size on the phylogenetic tree. A maximum likelihood was used to construct the phylogenetic tree (unrooted), as based on the core and accessory genes. Citrobacter species are colour coded in terms of their different respective clusters. The first, inner circle represents the sources of the strains, and the second, outer circler the beta-lactamase genes (bla-_CMY) identified in this study