Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2004-6-30
pubmed:abstractText
In Salmonella enterica, the PhoP-PhoQ two-component system governs resistance to structurally different antimicrobial peptides including the alpha-helical magainin 2, the beta-sheet defensins and the cyclic lipopeptide polymyxin B. To identify the PhoP-regulated determinants mediating peptide resistance, we prepared a plasmid library from a phoP mutant, introduced it into a phoP mutant and selected for magainin-resistant clones. One of the clones harboured the PhoP-activated ugtL gene, deletion of which rendered Salmonella susceptible to magainin 2 and polymyxin B, but not defensin HNP-1. We established that ugtL encodes an inner membrane protein that promotes the formation of monophosphorylated lipid A in the lipopolysaccharide. Inactivation of both ugtL and the regulatory gene pmrA, which controls lipid A modifications required for resistance to polymxyin B (but not to magainin 2) and is post-transcriptionally activated by the PhoP-PhoQ system, resulted in a strain that was as susceptible to polymyxin B as a phoP mutant. The most frequently recovered clone harboured the yqjA gene, which we show is PhoP regulated and required for resistance to magainin 2 but not to polymyxin B or defensin HNP-1. Our results indicate that different PhoP-mediated modifications in lipid A are necessary for resistance to different antimicrobial peptides.
pubmed:grant
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
53
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
229-41
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
PhoP-regulated Salmonella resistance to the antimicrobial peptides magainin 2 and polymyxin B.
pubmed:affiliation
Department of Molecular Microbiology, Campus Box 8230, Washington University, St Louis, MO 63110, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't