Linked Life Data

11390688

Source:http://linkedlifedata.com/resource/pubmed/id/11390688

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
Pt 6
pubmed:dateCreated
2001-6-6
pubmed:abstractText
The sigma(54) RNA polymerase subunit has a prominent role in susceptibility of Listeria monocytogenes and Enterococcus faecalis to mesentericin Y105, a class IIa bacteriocin. Consequently, sigma(54)-dependent genes as well as specific activators also required for expression of these genes were sought. Five putative sigma(54)-associated activators were detected in the genome of E. faecalis V583, and all but one could activate the transcription of permease genes belonging to sugar phosphotransferase systems (PTSs). Interestingly, these activators display a helicase signature not yet reported in this activator family, which could explain the ATP-dependent mechanism of DNA unwinding preceding the start of transcription. To find which activator is linked to susceptibility of E. faecalis to mesentericin Y105, their respective genes were subsequently interrupted. Among them, only mptR gene interruption led to a resistance phenotype. Immediately downstream from mptR, a putative sigma(54)-dependent operon was found to encode a mannose PTS permease, namely EII(t)(Man). Moreover, in liquid culture, glucose and mannose induced the sensitivity of E. faecalis to mesentericin Y105. Since sugars have previously been reported to induce PTS permease expression, it appears that EII(t)(Man) expression, presumably induced in the presence of glucose and mannose, leads to an enhanced sensitivity of E. faecalis to the bacteriocin. Additional information was gained from knockouts within the permease operon. Interruption of the distal mptD gene, which encodes the IID subunit of EII(t)(Man), strikingly led to resistance to mesentericin Y105. Moreover, MptD appears to be a peculiar membrane subunit, bearing an additional domain compared to most known IID subunits. According to these results, EII(t)(Man) is clearly involved in susceptibility to mesentericin Y105 and could even be its receptor at the E. faecalis surface. Finally, it is hypothesized that MptD could be responsible for the targeting specificity, via an interaction between its additional domain and mesentericin Y105.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1350-0872
pubmed:author
pubmed:issnType
Print
pubmed:volume
147
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1575-80
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Analysis of sigma(54)-dependent genes in Enterococcus faecalis: a mannose PTS permease (EII(Man)) is involved in sensitivity to a bacteriocin, mesentericin Y105.
pubmed:affiliation
Laboratoire de Microbiologie Fondamentale et Appliquée, CNRS FRE 2224, IBMIG, UFR Sciences, 40 avenue du Recteur Pineau, 86022 Poitiers Cedex, France. yann.hechard@univ-poitiers.fr
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't