Linked Life Data

7756355

Source:http://linkedlifedata.com/resource/pubmed/id/7756355

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1995-6-26
pubmed:abstractText
The leakage induced by melittin, a membrane-perturbing amphipathic peptide, from large unilamellar 1-palmitoyl-2-oleoylphosphatidylcholine (POPC) vesicles was studied using calcein as fluorescent marker. The extent of leakage has been found to be regulated by the melittin/lipid molar ratio. Melittin leads to the complete release of trapped calcein from some vesicles. This all-or-none mechanism leads to the co-existence of two different vesicle populations: the 'empty' and the intact one. Intervesicular migration of melittin was not observed. The results reveal a specific targeting of the lysed vesicles by melittin. The presence of negatively charged lipids (unprotonated palmitic acid or 1-palmitoyl-2-oleoylphosphatidylglycerol) in the neutral POPC matrix inhibits the lytic power of melittin; this inhibition increases with increasing surface charge density. It is proposed that the anchorage of the peptide on the charged surface prevents the formation of defects allowing leakage. A statistical model based on a random distribution of the peptide molecules on the vesicles is proposed to describe the release induced by melittin. It is proposed that about 250 melittin molecules per vesicle are required to affect the bilayer permeability and to empty a vesicle of its content. This large number suggests that leakage is more likely due to collective membrane perturbation by the peptide rather than to the formation of a well-defined pore.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
4
pubmed:volume
1235
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
452-60
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Study of vesicle leakage induced by melittin.
pubmed:affiliation
Département de Chimie, Université de Montréal, Québec, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't