Genetic map, of Escherichia coli

Physical Structure of the Bacterial Chromosome The Genetic Map of Escherichia coli Eukaryotic DNA Is Complexed with Histones Organization of Genes within Eukaryotic... 

The genetic maps of Escherichia coli K12 and the closely related Salmonella typhi-murium LT2 can be aligned, but differ by an inversion of about 10% of their length symmetrically disposed about the terminus of replication [68] and by 14 (in Escherichia coli K12) and 15 (in Salmonella typhimurium LT2) loops of sequence not present in the other species [69,70]. 

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