Linked Life Data

8057855

Source:http://linkedlifedata.com/resource/pubmed/id/8057855

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1994-9-14
pubmed:databankReference
pubmed:abstractText
The human gastric bacterial pathogen Helicobacter pylori has been implicated in type B gastritis, peptic ulceration and gastric adenocarcinoma. Here we report on the cloning and genetic characterization of an H. pylori gene named vacA, which encodes the vacuolating cytotoxin VacA, a novel type of antigenic bacterial toxin that induces the formation of intracellular vacuoles in epithelial cells. The vacuolating cytotoxin activity is expressed by a subset of clinical isolates (Vac+), all of which produce the 87 kDa cytotoxin antigen, but strains which produce neither the activity nor the cytotoxin protein (Vac-) also carry the gene. Isogenic H. pylori mutants in vacA generated by transposon shuttle mutagenesis produce neither the VacA antigen nor a vacuolating activity in a cell culture model. The vacA gene itself encodes a precursor protein of 139.6 kDa consisting of a 33-amino acid signal sequence, the 87 kDa cytotoxin and a 50 kDa C-terminal domain with features typical of a bacterial outer membrane protein. The VacA precursor shows no significant primary sequence homology with any previously reported protein, but its structural organization closely resembles the IgA protease-type of exoprotein produced by pathogenic Neisseriae and Haemophilus species. Our current data support a model for secretion of the cytotoxin through the two bacterial membranes which involves the 50 kDa domain for outer membrane translocation with subsequent proteolytic cleavage and release of the mature 87 kDa cytotoxin into the extracellular environment.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
307-19
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Genetic analysis of the Helicobacter pylori vacuolating cytotoxin: structural similarities with the IgA protease type of exported protein.
pubmed:affiliation
Max-Planck-Institut für Biologie, Abteilung Infektionsbiologie, Tübingen, Germany.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't