%0 Journal Article
%T Diverse genome structures of Salmonella paratyphi C
%A Wei-Qiao Liu
%A Gui-Rong Liu
%A Jun-Qian Li
%A Guo-Min Xu
%A Danni Qi
%A Xiao-Yan He
%A Juan Deng
%A Feng-Min Zhang
%A Randal N Johnston
%A Shu-Lin Liu
%J BMC Genomics
%D 2007
%I BioMed Central
%R 10.1186/1471-2164-8-290
%X We constructed a high resolution genome map in S. paratyphi C strain RKS4594 and located four insertions totaling 176 kb (including the 90 kb SPI7) and seven deletions totaling 165 kb relative to S. typhimurium LT2. Two rearrangements were revealed, including an inversion of 1602 kb covering the ter region and the translocation of the 43 kb I-CeuI F fragment. The 23 wild type strains analyzed in this study exhibited diverse genome structures, mostly as a result of recombination between rrn genes. In at least two cases, the rearrangements involved recombination between genomic sites other than the rrn genes, possibly homologous genes in prophages. Two strains had a 20 kb deletion between rrlA and rrlB, which is a highly conservative region and no deletion has been reported in this region in any other Salmonella lineages.S. paratyphi C has diverse genome structures among different isolates, possibly as a result of large genomic insertions, e.g., SPI7. Although the Salmonella typhoid agents may not be more closely related among them than each of them to other Salmonella lineages, they may have evolved in similar ways, i.e., acquiring typhoid-associated genes followed by genome structure rearrangements. Comparison of multiple Salmonella typhoid agents at both single sequenced genome and population levels will facilitate the studies on the evolutionary process of typhoid pathogenesis, especially the identification of typhoid-associated genes.Of the over 2500 Salmonella serotypes recognized to date [1], about 1400 infect humans and other warm-blooded vertebrates, which are classified into Salmonella subgroup I (now often referred to as Salmonella enterica subspecies enterica [2-4]). Although most of these Salmonella serotypes cause self-limiting gastroenteritis in humans, four cause typhoid fever, a serious and potentially fatal systemic infection, including S. typhi (see a recent review [5]) and S. paratyphi A, B and C. It is a long unanswered question whether different
%U http://www.biomedcentral.com/1471-2164/8/290