Linked Life Data

11489125

Source:http://linkedlifedata.com/resource/pubmed/id/11489125

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2001-8-7
pubmed:abstractText
Helicobacter pylori (Hp), a Gram-negative bacterial pathogen and aetiologic agent of gastroduodenal disease in humans, is naturally competent for genetic transformation. Natural competence in bacteria is usually correlated with the presence of type IV pili or type IV pilin-like proteins, which are absent in Hp. Instead, we recently identified the comB operon in Hp, carrying four genes tentatively designated as orf2, comB1, comB2 and comB3. We show here that all ComB proteins and the 37-amino-acid Orf2 peptide display significant primary sequence and structural homology/identity to the basic components of a type IV secretion apparatus. ComB1, ComB2 and ComB3, now renamed ComB8, ComB9 and ComB10, correspond to the Agrobacterium tumefaciens VirB8, VirB9 and VirB10 proteins respectively. The peptide Orf2 carries a lipoprotein motif and a second cysteine residue homologous to VirB7, and was thus designated ComB7. The putative ATPase ComB4, encoded by the open reading frame hp0017 of strain 26695, corresponds to virB4 of the A. tumefaciens type IV secretion system. A Hp comB4 transposon insertion mutant was totally defective in natural transformation. By complementation of a Hp DeltacomB deletion mutant, we demonstrate that each of the proteins from ComB8 to ComB10 is absolutely essential for the development of natural transformation competence. The putative lipoprotein ComB7 is not essential, but apparently stabilizes the apparatus and modulates the transformation efficiency. Thus, pathogenic type I Hp strains contain two functional independent type IV transport systems, one for protein translocation encoded by the cag pathogenicity island and one for uptake of DNA by natural transformation. The latter system indicates a possible novel mechanism for natural DNA transformation in bacteria.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
41
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
379-91
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:11489125-Amino Acid Sequence, pubmed-meshheading:11489125-Bacterial Proteins, pubmed-meshheading:11489125-Binding Sites, pubmed-meshheading:11489125-Biological Transport, pubmed-meshheading:11489125-Cell Membrane, pubmed-meshheading:11489125-DNA-Binding Proteins, pubmed-meshheading:11489125-Genetic Complementation Test, pubmed-meshheading:11489125-Helicobacter pylori, pubmed-meshheading:11489125-Membrane Proteins, pubmed-meshheading:11489125-Molecular Sequence Data, pubmed-meshheading:11489125-Open Reading Frames, pubmed-meshheading:11489125-Operon, pubmed-meshheading:11489125-Plasmids, pubmed-meshheading:11489125-Protein Binding, pubmed-meshheading:11489125-Protein Processing, Post-Translational, pubmed-meshheading:11489125-Protein Structure, Tertiary, pubmed-meshheading:11489125-Sequence Analysis, Protein, pubmed-meshheading:11489125-Sequence Deletion, pubmed-meshheading:11489125-Sequence Homology, Amino Acid, pubmed-meshheading:11489125-Transformation, Bacterial
pubmed:year
2001
pubmed:articleTitle
Natural transformation competence in Helicobacter pylori is mediated by the basic components of a type IV secretion system.
pubmed:affiliation
Max von Pettenkofer Institut für Hygiene und Medizinische Mikrobiologie, Pettenkoferstr. 9a, D-80336 München, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't