Linked Life Data

19708916

Source:http://linkedlifedata.com/resource/pubmed/id/19708916

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2009-9-29
pubmed:abstractText
The PhoPQ two-component system of the intracellular pathogen Salmonella enterica senses and controls resistance to alpha-helical antimicrobial peptides (AMPs) by regulating covalent modifications of lipid A. A homologue of the phoPQ operon was found in the genome of the murine enteric extracellular pathogen, Citrobacter rodentium. Here we report that C. rodentium PhoPQ was apparently unable to mediate activation of target genes in the presence of alpha-helical AMPs. However, these AMPs activated C. rodentium PhoPQ expressed in a S. entericaDeltaphoPQ mutant. Analysis of the outer membrane (OM) fractions of the C. rodentium wild-type and DeltaphoPQ strains led to the identification of an omptin family protease (CroP) that was absent in DeltaphoPQ. Deletion of croP in C. rodentium resulted in higher susceptibility to alpha-helical AMPs, indicating a direct role of CroP in AMP resistance. CroP greatly contributed to the protection of the OM from AMP damage by actively degrading alpha-helical AMPs before they reach the periplasmic space. Accordingly, transcriptional activation of PhoP-regulated genes by alpha-helical AMPs was restored in the DeltacroP mutant. This study shows that resistance to alpha-helical AMPs by the extracellular pathogen C. rodentium relies primarily on the CroP OM protease.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1365-2958
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
74
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
98-111
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
An outer membrane protease of the omptin family prevents activation of the Citrobacter rodentium PhoPQ two-component system by antimicrobial peptides.
pubmed:affiliation
Department of Microbiology and Immunology, McGill University, Montreal, QC, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't