Folkesson, A., Advani, A., Sukupolvi, S.,Pfeifer,J.D.,Normark, S.,Lofdahl, S. (1999) Multiple insertions of fimbrial operons correlate with the evolution of Salmonella serovars responsible for human disease. Molecular Microbiology 33: 612-622.

Anders Folkesson, Abdolreza Advani, Soila Sukupolvi, John D. Pfeifer, Staffan Normark, Sven Löfdahl

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On centisome 7, Salmonella spp. contain a large region not present in the corresponding region of Escherichia coli. This region is flanked by sequences with significant homology to the E. coli tRNA gene aspV and the hypothetical E. coli open reading frame yafV. The locus consists of a mosaic of differentially acquired inserts forming a dynamic cs7 region of horizontally transferred inserts. Salmonella enterica subspecies I, responsible for most Salmonella infections in warm-blooded animals, carries a fimbrial gene cluster (saf) in this region as well as a regulatory gene (sinR). These genes are ¯anked by inverted repeats and are inserted in another laterally transferred
region present in most members of Salmonella spp. encoding a putative invasin (pagN ). S. enterica subspecies I serovar Typhi, the Salmonella serovar that causes the most severe form of human salmonellosis, contains an additional insert of at least 8 kb in the sinR ±pagN intergenic region harbouring a novel fimbrial operon (tcf ) similar to the coo operon encoding the CS1 fimbrial adhesin expressed by humanspecific enterotoxigenic E. coli. It is suggested that the multiple insertions of fimbrial genes that have
occurred in the cs7 region have contributed to phylogenetic diversity and host adaptation of Salmonella spp.
Original languageEnglish
JournalMolecular Microbiology
Issue number3
Number of pages11
Publication statusPublished - 1999
Externally publishedYes

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