The ST2 3990 strain contained also two plasmids, p1-ABST2 carrying a complete tra locus, and p2-ABST2 carrying one copy of the CHDL bla OXA-58 gene. p1-ABST2 and p2-ABST2 were homologous to plasmids pACICU2 and pACICU1 identified in the ST2 ACICU strain [12], respectively. While p1-ABST2 and pACICU2 are almost identical, p2-ABST2 shares only two third of the coding

sequences with pACICU1. Neratinib mw The plasmid p1-ABST78 identified in the ST78 3909 strain shares approximately 80% of the coding sequences, including the bla OXA-58 gene, with plasmid pACICU1 (Additional files 1 and 2). The different plasmids were classified using the PCR-typing procedure recently described [13]. A conserved scaffold that includes four/five direct perfect repeats that can be defined as “”iterons”", and the gene encoding the replicase repAci1 belonging to the Rep-3 superfamily and assigned to the GR2 homology group, was found in plasmids pACICU1, p2ABST2, p2ABST25 and p1ABST78. The repAciX replicase (Rep-3 superfamily, GR10 homology group) is encoded by plasmids pACICU1 and p2ABST2, the Aci6 replicase (GR6 homology group) by pACICU2 and p1ABST2 plasmids. A protein identical to the replicase encoded by plasmid pMMA2 carrying the bla OXA-24 gene [14], is encoded by p1ABST25. While sharing common sequences, all plasmids exhibited a mosaic genetic structure

that might have been generated by multiple recombination events. The hypothetical gene products encoded by the plasmids found in the A. baumannii strains 3990, 3909 and 4190 are listed

in Additional Gefitinib supplier file 2. The A. baumannii chromosome Making use of the Mauve software [15], the proteins putatively encoded by the draft genomes of the A. baumannii strains 3990, 3909 and 4190 [11] were compared to the ORFs encoded by the wholly sequenced genomes of the A. baumannii AB0057 and AYE strains assigned to ST1, ACICU strain assigned to ST2, ATCC17978 strain assigned to ST77 [12, 16–18]. A. baumannii genomes exhibit extensive RANTES synteny. Sequence comparisons revealed that 3068 coding regions are conserved, at the same chromosomal position, in the compared A. baumannii genomes. A file including all conserved gene products is available upon request. Genes encoding proteins shown or hypothesized to be important for pathogenicity are conserved in the analyzed strains at the same relative chromosomal position (Table 1). The set includes OmpA, the outer membrane protein which has role in biofilm formation [19] and induces, when secreted, death of epithelial and dendritic cells [20], the DD-endopeptidase, which contributes to the resistance of A. baumannii to bactericidal activity presumably by remodelling the cell surface [21], phospholipase D, an enzyme crucial for proliferation in human serum [22], proteins involved in the formation of capsule [23], type I pili [24], and iron metabolism [25].