Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
1989-2-23
pubmed:abstractText
The effect of hydrophobicity on the rate and mechanism of transfer of a synthetic amphiphilic peptide between phosphatidylcholine single bilayer vesicles has been evaluated. These peptides, which had the sequence Cn-SSLKEYWSSLKESFS (where Cn represents a saturated acyl chain of n carbons that is attached to the amino terminus of the peptide and n = 8, 12, or 16), were distinguished by the length of the saturated acyl chain of n carbons that was covalently bonded to the amino terminus. The transfer of the peptides was monitored by following the rate of change of the intrinsic tryptophan fluorescence that followed mixing of donor vesicles, which contained peptide, phosphatidylcholine, and a fluorescence quencher, with acceptors composed only of phosphatidylcholine. The transfer rates were independent of the structure and concentration of the acceptor. The kinetics were biexponential with the contribution of the fast and slow components being nearly equal. The rates of both components decreased with increasing acyl chain length; the respective free energies of activation were linear with respect to the acyl chain length. These results showed that, unlike lipid transfer, peptide transfer is not always a simple unimolecular process. However, like lipid transfer, the transfer rates are a predictable function of hydrophobicity. It is proposed that the peptides exist as dimers on the phospholipid surface and that the two components of transfer are due to sequential transfer of each molecule in a dimer.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
4
pubmed:volume
27
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7881-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Kinetics and mechanism of transfer of synthetic model apolipoproteins.
pubmed:affiliation
Department of Medicine, Baylor College of Medicine, Houston, Texas.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.