Genomic islands responsible for the utilization of nitrate (A), melibiose (B) and lactose (C). (A) The nitrate locus contains: the genes encoding the molybdopterin modB, modA, mog and moaA and the genes encoding the nitrate reductase narK, narG, narH, narJ, narI. The sequence inside red pipes is lacking in nitrate negative strains. (B)The melibiose genomic island of the CIRM BIA 513 strain contains rbsR encoding a transcriptional factor, aga encoding an alpha-amylase and msmE, amyC and amyD encoding to a melibiose ABC transporter. These latter (red frame) has a GC skew that is less marked than the remainder of the genome (57% versus 67%, respectively). (C) Strains capable of lactose utilization possess a genomic island containing galE1, galP and lacZ encoding an UDP-glucose epimerase, a lactose transporter and a beta-galactosidase respectively. The island contains several transposases and integrase, suggesting an integration of the island by transduction and transposition. The red pipe indicates the 3’ part of the island. The 5’ part of the island is not the same for all lactose positive strains. Other genomic islands cited in Table 4 are available on the genome browser of EBI website.