Virulence-associated genetic regions comprising 31 kilobases of the 230-kilobase plasmid in Shigella flexneri 2a.
AUTOR(ES)
Sasakawa, C
RESUMO
By random transposon Tn5 insertions, we previously identified six virulence-associated SalI fragments, B, D, F, G, H, and P, in the 230-kilobase plasmid pMYSH6000 of Shigella flexneri 2a. In this study, we analyzed the sites of 134 independent Tn5 insertions on four contiguous SalI fragments, B, P, H, and D, of pMYSH6000 and identified five virulence-associated regions; four were associated with inducing a positive Sereny test (Ser), invasion into epithelial cells (Inv), binding to Congo red (Pcr), and inhibition of bacterial growth (Igr), and one was associated with the Ser and Inv but not with the Pcr or Igr phenotypes. Hybridization studies revealed that these virulence-associated DNA regions were highly conserved among 15 other virulence plasmids of four species of Shigella and enteroinvasive Escherichia coli. These data indicate that at least seven separate genetic determinants on the virulence plasmid are required for full expression of the virulence phenotype of shigellae.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=211159Documentos Relacionados
- Loss of pigmentation in Shigella flexneri 2a is correlated with loss of virulence and virulence-associated plasmid.
- Role of the 85-Kilobase Plasmid and Plasmid-Encoded Virulence-Associated Protein A in Intracellular Survival and Virulence of Rhodococcus equi
- New virulence-associated plasmid in Yersinia enterocolitica.
- Presence of a virulence-associated plasmid in Yersinia pseudotuberculosis.
- Regulation of virulence-associated plasmid genes in enteroinvasive Escherichia coli.