(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) > cellular organisms: NE > Bacteria: NE > Proteobacteria: NE > Gammaproteobacteria: NE > Enterobacterales: NE > Enterobacteriaceae: NE > Shigella: NE > Shigella dysenteriae: NE
Warning: This entry is a compilation of different species or line or strain with more than 90% amino acide identity. You can retrieve all strain data
(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) Shigella dysenteriae Sd197: N, E.
Shigella dysenteriae CDC 74-1112: N, E.
Shigella dysenteriae 1617: N, E.
Shigella dysenteriae 155-74: N, E.
Shigella dysenteriae 225-75: N, E.
Salmonella enterica subsp. enterica serovar Kentucky str. CVM29188: N, E.
Enterobacter cancerogenus ATCC 35316: N, E.
LegendThis sequence has been compared to family alignement (MSA) red => minority aminoacid blue => majority aminoacid color intensity => conservation rate title => sequence position(MSA position)aminoacid rate Catalytic site Catalytic site in the MSA MYAREYRSTRPHKAIFFHLSCLTLICSAQVYAKPDMRPLGPNIADKGSVF YHFSVTSFDSVDGTRHYRVWTAVPNTTAPASGYPILYMLDGNAVMDRLDD ELLKQLSEKTPPVIVAVGYQTNFPFDLNSRAYDYTPAAESRKTDLHSGRF SRKSGGSNNFRQLLETRIAPKVEQGLNIDRQRRGLWGHSYGGLFVLDSWL SSSYFRSYYSASPSLGRGYDALLSRVTAVEPLQFCAKHLAIMEGSATQGD NRETHAVGVLSKIHTTLTILKDKGVNVVFWDFPNLGHGPMFNASFRQALL DISGENANYTAGCHELSH
Salmonella enterica, a leading cause of food-borne gastroenteritis worldwide, may be found in any raw food of animal, vegetable, or fruit origin. Salmonella serovars differ in distribution, virulence, and host specificity. Salmonella enterica serovar Kentucky, though often found in the food supply, is less commonly isolated from ill humans. The multidrug-resistant isolate S. Kentucky CVM29188, isolated from a chicken breast sample in 2003, contains three plasmids (146,811 bp, 101,461 bp, and 46,121 bp), two of which carry resistance determinants (pCVM29188_146 [strAB and tetRA] and pCVM29188_101 [bla(CMY-2) and sugE]). Both resistance plasmids were transferable by conjugation, alone or in combination, to S. Kentucky, Salmonella enterica serovar Newport, and Escherichia coli recipients. pCVM29188_146 shares a highly conserved plasmid backbone of 106 kb (>90% nucleotide identity) with two virulence plasmids from avian pathogenic Escherichia coli strains (pAPEC-O1-ColBM and pAPEC-O2-ColV). Shared avian pathogenic E. coli (APEC) virulence factors include iutA iucABCD, sitABCD, etsABC, iss, and iroBCDEN. PCR analyses of recent (1997 to 2005) S. Kentucky isolates from food animal, retail meat, and human sources revealed that 172 (60%) contained similar APEC-like plasmid backbones. Notably, though rare in human- and cattle-derived isolates, this plasmid backbone was found at a high frequency (50 to 100%) among S. Kentucky isolates from chickens within the same time span. Ninety-four percent of the APEC-positive isolates showed resistance to tetracycline and streptomycin. Together, our findings of a resistance-conferring APEC virulence plasmid in a poultry-derived S. Kentucky isolate and of similar resistance/virulence plasmids in most recent S. Kentucky isolates from chickens and, to lesser degree, from humans and cattle highlight the need for additional research in order to examine the prevalence and spread of combined virulence and resistance plasmids in bacteria in agricultural, environmental, and clinical settings.
The Shigella bacteria cause bacillary dysentery, which remains a significant threat to public health. The genus status and species classification appear no longer valid, as compelling evidence indicates that Shigella, as well as enteroinvasive Escherichia coli, are derived from multiple origins of E.coli and form a single pathovar. Nevertheless, Shigella dysenteriae serotype 1 causes deadly epidemics but Shigella boydii is restricted to the Indian subcontinent, while Shigella flexneri and Shigella sonnei are prevalent in developing and developed countries respectively. To begin to explain these distinctive epidemiological and pathological features at the genome level, we have carried out comparative genomics on four representative strains. Each of the Shigella genomes includes a virulence plasmid that encodes conserved primary virulence determinants. The Shigella chromosomes share most of their genes with that of E.coli K12 strain MG1655, but each has over 200 pseudogenes, 300 approximately 700 copies of insertion sequence (IS) elements, and numerous deletions, insertions, translocations and inversions. There is extensive diversity of putative virulence genes, mostly acquired via bacteriophage-mediated lateral gene transfer. Hence, via convergent evolution involving gain and loss of functions, through bacteriophage-mediated gene acquisition, IS-mediated DNA rearrangements and formation of pseudogenes, the Shigella spp. became highly specific human pathogens with variable epidemiological and pathological features.
