The original IS200 insertion is (hisD984). IS200 contains a strong rho-independent transcription terminator. It transposes at an extremely low frequency, and no excision has been observed. The EMBL sequence has +1 frameshift error (Casadesus, J., 1993). IS200 is not present in Citrobacter freundii (4 strains), Enterobacter aerogenes (5 strains), Klebsiella pneumoniae (2 strains), Serratia marcescens (6 strains), Proteus mirabilis (10 strains). In the SARA collection of Salmonella, IS200 occurs in 65 % of the strains, with some harbouring as many as 19 copies of the element (Bisercic and Ochman, 1993b). The six IS200 chromosomal locations in Salmonella typhimurium LT2 have been physically and genetically mapped (Sanderson et al., 1993). Also, a 324-nt segment (Accession Number D00497) corresponding to the 3' end of IS200 (Ohnishi et al., 1990) has also been found (noticed by S. Brynestad, pers. comm., 1996) 162 nt upstream the fliA gene which encodes an alternative sigma factor specific for flagellar operon. Recently, it was shown that this 711-bp IS200 copy (most probably IS200F) is located 37 bp downstream of the fliB gene (whose product has been shown to N-methylate lysine residues of Salmonella flagellins) (Burnens et al., 1997). As far as genomic lineage is concerned, IS200 typing is not appropriate to discriminate among strains of Salmonella enterica serovar Dublin (Olsen and Skov, 1994), or Salmonella enteritidis (Millemann et al., 1995; although Olsen et al., 1994 disagreed!), but well for Salmonella typhimurium (Baquar et al., 1994a; Schwarz and Liebisch, 1994; Millemann et al., 1995, Olsen et al., 1997), where at least 7 hybridization patterns have been observed, Salmonella infantis (Pelkonen et al., 1994), and Salmonella heidelberg (Stanley et al., 1992a). In Salmonella abortusovis, all the isolates tested proved to contain 3 or 4 copies of IS200 (Schiaffino et al., 1996). A comprehensive analysis of all known IS200 (Beuzon et al., 1997) suggests a very low transposition frequency and supports the hypothesis that IS200 is an ancestral element of the Enterobacteriaceae.
July 16 2012 : we deleted some files with partial sequences and added the informations in IS200 file :
IS200A is associated with the gpt-83 mutation.
IS200B has been obtained through PCR amplification of an internal fragment of IS200.
IS200D (Accession number : L25846) has been obtained through PCR amplification of an internal fragment of IS200. The putative transposase of this IS200 element is quite interesting: when compare to the other members of the family, one sees a "displacement" of a 19-aa fragment in the protein from position 32 to position 70 !!! This rearrangement generates a "false" % of similarity.
IS200E (Accession number : L25847) has been obtained through PCR amplification of an internal fragment of IS200.
IS200I (Accession number : AF439538) is 98% aa similar to IS200B for the first 82 aa and 95% for the last 70 aa. There is a frameshift at position 366-367. IS200I is inserted in an intergenic region between eae and escD.
IS200P (Accession number : Y09564) has been recovered after its insertion into the virulent plasmid pSLT of Salmonella typhimurium (Beuzon et al., 1997), within the fimbrial operon pef. This insertion has apparently led to the duplication of a single bp. Note that the IS200P putative transposase (151 aa (143-598)) deduced from the DNA sequence (EMBL Database) contains a stop codon at position 11 (in place of R), although its is reported to be an intact transposase by Beuzon et al. (1997).