FIG 2.
In silico detection of the protein-encoding genes of the Shigella virulence plasmid. The BSRs were determined for all of the protein-encoding genes by comparing the amino acid sequences encoded by invasion plasmid pCP301 (accession no. NC_004851.1) from S. flexneri 2a strain 301 to each of the EIEC and Shigella genomes by using TBLASTN (37). The heat map and a hierarchical cluster analysis were generated with MeV (83) as previously described (29). The colors of the heat map indicate the presence of each protein-encoding gene with significant similarity (yellow) or divergent similarity (black) or its absence (blue). Each column represents a different gene, and each row is a different genome. The isolates are color coded by species and lineage on the right. The EIEC genomes are designated by yellow circles, while the Shigella genomes are designated by green circles. Genomes of EIEC lineage 1 are indicated by blue squares, those of lineage 2 are indicated by purple squares, and those of lineage 3 are indicated by orange squares. The Mxi-Spa-Ipa region and a second variable region, designated II, are identified by the red and black lines at the top, respectively. Region II contains plasmid stability proteins, a methyltransferase, and hypothetical proteins.