English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Edwardsiella tarda is an enteric pathogen that causes diarrhea, wound infections, and death due to septicemia. This species is capable of invading human epithelial cell lines, and we have now been able to follow the entry and replication of E. tarda within tissue culture host cells. E. tarda escapes from the endocytic vacuole within minutes of entry and then replicates within the cytoplasm. Unlike other well-studied bacteria that replicate and reside in the cytoplasm, we never observed this organism moving directly from cell to cell; instead the bacteria spread by lysing the plasma membrane after several rounds of replication. Efforts to study the interactions of E. tarda with tissue culture cells are complicated by the presence of a potent cytotoxin that the bacterium produces. Using transposon mutagenesis, we isolated a noncytotoxic strain of E. tarda. This mutant is also defective for hemolysin production. The dual phenotype of this strain is consistent with the hypothesis that cytotoxicity is due to the previously characterized E. tarda hemolysin activity. The nonhemolytic strain is also unable to enter HEp-2 cells. The disrupted gene has sequence similarity to members of a family of genes required for transport and activation of the hemolysin genes, shlA and hpmA. A cosmid bearing 40 kb of E. tarda DNA, including wild-type copies of the E. tarda homologs of the transporter-activator protein and the hemolysin itself, confers hemolytic, cytotoxic, and invasive abilities upon normally nonhemolytic, noncytotoxic, and noninvasive strains of Escherichia coli. Sequence data indicate that the genes required for hemolytic activity are linked to a transposable element, suggesting that they arose in the E. tarda genome by horizontal transfer.

An Edwardsiella tarda strain containing a mutation in a gene with homology to shlB and hpmB is defective for entry into epithelial cells in culture