Shigella species and enteroinvasive @entity526 contain a core set of virulence genes whose coordinated expression results in the invasion of host @entity694 . A number of virulence determinants are carried by the 230 kb invasion plasmid found in all virulent strains of Shigellae. Many of these invasion plasmid genes encode immunogens that are recognized by convalescent serum, including proteins that mediate the invasion (IpaB, IpaC, IpaD) and cell spreading (VirG or IcsA and IcsB) phenotypes. In this report, we describe the molecular characterization of a novel invasion plasmid antigen from @entity14341 , designated IpaJ. The ipaJ gene encodes a 780 bp @entity5545 ( @entity5545 ), separated from the ipaR (virB) stop codon by 944 bp. The predicted amino acid sequence for IpaJ revealed a consensus signal peptide for protein export. TnphoA mutagenesis of the ipaJ @entity5545 confirmed the presence of export signal sequences in IpaJ. Unlike ipaBCDA genes, transcription analysis of ipaJ indicated that the gene is not expressed in a temperature-dependent fashion. The IpaJ protein was expressed and purified as a His6-tagged fusion protein that reacted with convalescent sera in Western blot analyses, confirming its identification as a Shigella immunogen. Construction and phenotypic characterization of ipaJ mutants in two serotypes of @entity14341 showed that the mutants were not compromised in their ability to invade cultured epithelial cells or to form plaques on BHK cell monolayers. In addition, the ipaJ mutants were Sereny positive indicating a capacity for intercellular dissemination; however, in the limited number of @entity840 tested, the @entity9849 reaction appeared attenuated.

Identification and molecular characterization of a 27 kDa XXXX invasion plasmid antigen, IpaJ.

@entity9849 :: ('MESH:D007637', 'Disease') :: ['keratoconjunctivitis'] @entity840 :: ('10141', 'Species') :: ['guinea-pigs'] @entity14341 :: ('623', 'Species') :: ['Shigella flexneri', 'S. flexneri'] @entity694 :: ('MESH:D003110', 'Disease') :: ['colonic epithelial cells and the dysenteric syndrome'] @entity526 :: ('562', 'Species') :: ['Escherichia coli'] @entity5545 :: ('MESH:D004410', 'Disease') :: ['ORF', 'open reading frame']
@entity14341 :: (623,Species) :: ['Shigella flexneri']
