Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
33
pubmed:dateCreated
2000-9-12
pubmed:abstractText
Perfringolysin O (PFO) is a member of the cholesterol-dependent cytolysin (CDC) family of membrane-penetrating toxins. The CDCs form large homooligomers (estimated to be comprised of up to 50 CDC monomers) that are responsible for generating a large pore in cholesterol-containing membranes of eukaryotic cells. The assembly of the PFO cytolytic complex was examined to determine whether it forms an oligomeric prepore complex on the membrane prior to the insertion of its membrane-spanning beta-sheet. A PFO oligomeric complex was formed on liposomes at both 4 degrees C and 37 degrees C and shown by SDS-agarose gel electrophoresis to be comprised of a large, comparatively homogeneous complex instead of a distribution of oligomer sizes. At low temperature, the processes of oligomerization and membrane insertion could be resolved, and PFO was found to form an oligomer without significant membrane insertion of its beta-hairpins. Furthermore, PFO was found to increase the ion conductivity through a planar bilayer by large and discrete stepwise changes in conductance that are consistent with the insertion of a preassembled pore complex into the bilayer. The combined results of these analyses strongly support the hypothesis that PFO forms a large oligomeric prepore complex on the membrane surface prior to the insertion of its transmembrane beta-sheet.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
22
pubmed:volume
39
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10284-93
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
The mechanism of pore assembly for a cholesterol-dependent cytolysin: formation of a large prepore complex precedes the insertion of the transmembrane beta-hairpins.
pubmed:affiliation
Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City 73190, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't