Genomic comparisons among Escherichia coli strains B, K-12, and O157:H7 using IS elements as molecular markers.

ABSTRACT:

Background

Insertion Sequence (IS) elements are mobile genetic elements widely distributed among bacteria. Their activities cause mutations, promoting genetic diversity and sometimes adaptation. Previous studies have examined their copy number and distribution in Escherichia coli K-12 and natural isolates. Here, we map most of the IS elements in E. coli B and compare their locations with the published genomes of K-12 and O157:H7.

Results

The genomic locations of IS elements reveal numerous differences between B, K-12, and O157:H7. IS elements occur in hok-sok loci (homologous to plasmid stabilization systems) in both B and K-12, whereas these same loci lack IS elements in O157:H7. IS elements in B and K-12 are often found in locations corresponding to O157:H7-specific sequen

SUBMITTER: Schneider D 

PROVIDER: S-EPMC117601 | biostudies-literature | 2002 Jul

REPOSITORIES: biostudies-literature