The fhuBCD genes, which catalyze the internalization

of iron III hydroxamate compounds, are located on G36, an island conserve in all strains but AB0057 and AYE. Metabolic islands RG7112 Many GEIs carry genes encoding proteins involved in specific metabolic pathways. G23ST25 carries a mph (multi component phenol hydroxylase) gene complex, involved in the conversion of phenol to cathecol, flanked by a sigma54-dependent activator gene. It has been shown that the expression of mph gene complex described in Acinetobacter sp. PHAE-2 is dependent on the alternative sigma factor RpoN [39]. G37ST25 carries nag genes, involved in the metabolism of naphthalene. In Ralstonia [40], nag genes are arranged in two separate clusters, involved in the conversion of naphthalene to gentisate (nagAGHBFCQED genes), and gentisate to pyruvate and fumarate (nagIKL genes), respectively. In G37ST25 nagIKL genes and nagGH, encoding the salicylate Selleck Y-27632 5-hydroxylase, are linked,

and flanked by benzoate transport genes. G43ST25 carries genes involved in the catabolism of 3HPP (3-hydroxyphenylpropionic acid) and PP (phenylpropionic acid). In E. coli, the dioxygenase complex (hcaEFCD genes), and the dihydrodiol dehydrogenase (hcaB gene) oxidize PP (phenylpropionic acid) and CI (cinnamic acid) to DHPP (2,3-dihydroxyphenylpropionate) and DHCI (2,3-dihydroxycinnamic acid), respectively. These substrates are subsequently converted to citric acid cycle intermediates by the mhp genes products [41]. The hca and mhp genes,

separated in E. coli, are linked and interspersed with additional genes (see Additional file 4) in G43ST25. G21ST25 potentially encodes 4 proteins (tartrate dehydratase subunits alpha and beta, a MFS transporter and a transcriptional regulator) possibly involved in the metabolism of tartrate. Proteins exhibiting homology to the dienelactone hydrolase, an enzyme which plays a crucial role in the degradation of chloro-aromatic compounds, are encoded by the islands G30ST25, G34abn and G34aby. G46ST25 is made by an operon including the salicylate 1-monooxygenase (salA), a benzoate transporter Aspartate (benK) and the salA regulator (salR) genes. A salicylate 1-monooxygenase is also encoded by G25ST25. The genes fabA, fabB, fabG, fabF, acpP, pslB, acsA, involved in the biosynthesis of fatty acids [35] are conserved in all A. baumannii strains, at separate loci. Orthologues of all these genes are clustered in G6abc and G6acb. Phage islands Many variable genomic regions are relatively large (19 to 82 kb) DNA blocks which potentially encode typical phage products. These regions have all been classified as cryptic prophages (CP; see Figure 2). Three to six CPs were identified in each strain. Six of the different 14 CPs identified are present in two or more strains, the remaining 8 are strain-specific.