The four -borne islands in MG1655 (), CFT073 (), Sf301 () and EDL933 () genomes identified by the tRNAcc method

Copyright information:Taken from "A novel strategy for the identification of genomic islands by comparative analysis of the contents and contexts of tRNA sites in closely related bacteria"Nucleic Acids Research 2006;34(1):e3-e3.Published online 9 Jan 2006PMCID:PMC1326021.© The Author 2006. Published by Oxford University Press. All rights reserved The 9.1 kb island in MG1655, 127.9 kb island in CFT073 and 55.1 kb island in Sf301 are flanked by conserved upstream (UF) and downstream (DF) backbone segments. However, the DF region, common to the other three genomes, is absent in EDL933. Instead, the first instance of a conserved chromosomal block common to the other genomes occurs 23.5 kb downstream of the EDL933 gene. This secondary conserved block has been designated as DF′. Matching 2 kb flanking regions are represented as connected blocks. In this study, genomic island-like regions were defined as anomalous segments between the 3′ end of tRNA genes and the 5′ end of the conserved downstream flank. Consequently, the tRNAcc-identified GIs in MG1655, CFT073 and Sf301 lay between the and DF loci, while that in EDL933 was defined as the segment between the gene and the proximal boundary of the DF′ conserved segment. The Islander-defined 104.6 and 46.7 kb islands at the locus in CFT073 and Sf301, respectively, are shown as red lines flanked by DR sequences (red rectangles).