Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
2001-4-30
pubmed:abstractText
Staphylococcal alpha-toxin forms heptameric pores on eukaryotic cells. After binding to the cell membrane in its monomeric form, the toxin first assembles into a heptameric pre-pore. Subsequently, the pre-pore transforms into the final pore by membrane insertion of an amphipathic beta-barrel, which comprises the "central loop" domains of all heptamer subunits. The process of membrane insertion was analyzed here using a set of functionally altered toxin mutants. The results show that insertion may be initiated within an individual protomer when its NH2 terminus activates its central loop. The activated state is then shared with the central loops of the residual heptamer subunits, which results in cooperative membrane penetration. This cooperation of the central loops commences while these are still remote from the lipid bilayer. Nevertheless, it is subject to modulation by the target membrane, which therefore acts across a distance much like an allosteric effector. However, while allosteric transitions usually are reversible, membrane insertion of alpha-toxin is an irreversible event, and we show here that it can proceed to completion in a domino-like fashion when triggered by as little as a single foreign atom within the entire heptamer.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
4
pubmed:volume
276
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
14835-41
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Membrane insertion of the heptameric staphylococcal alpha-toxin pore. A domino-like structural transition that is allosterically modulated by the target cell membrane.
pubmed:affiliation
Institute of Medical Microbiology and Hygiene, University of Mainz, Obere Zahlbacher Strasse 67, D55101 Mainz, Germany. avaleva@mail.uni-mainz.de
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't