Linked Life Data

1854750

Source:http://linkedlifedata.com/resource/pubmed/id/1854750

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
30
pubmed:dateCreated
1991-8-27
pubmed:abstractText
Fluorescence spectroscopy has been used to monitor the partitioning of a series of exchangeable neutral phospholipid probes, labeled with carbazole, indolyl or diphenylhexatrienyl moieties, between large unilamellar vesicles containing 1-palmitoyl-2-oleoylphosphatidylcholine (POPC), 1,2-dioleoyloxy-3-(trimethylammonio) propane (DOTAP) or N-hexadecyl-N-(9-octadecenyl)-N,N-dimethylammonium chloride (HODMA). Phosphatidylethanolamine (PE) probes desorb from POPC-containing vesicles at markedly slower rates than do phosphatidylcholine (PC) probes with the same acyl chains. The rate of probe desorption from such vesicles is progressively enhanced by successive N-methylations of the amino group but not by methylation of C-2 of the ethanolamine moiety, a modification that leaves unaltered the hydrogen-bonding capacity of the polar headgroup. By contrast, the rates of desorption of different probes (with the same acyl chains) from HODMA or from DOTAP vesicles are much more comparable and reflect no clear systematic influence of the headgroup hydrogen-bonding capacity. Equilibrium-partitioning measurements indicate that the relative affinities of different probes for PC-rich vesicles, in competition with HODMA or DOTAP vesicles, increase with increasing hydrogen-bonding capacity of the probe headgroup in the order PC less than N,N-dimethyl PE less than N-methyl PE less than PE approximately phosphatidyl-2-amino-1-propanol. From such partitioning data, we estimate that interlipid hydrogen-bonding interactions (in competition with lipid-water interactions) contribute roughly -300 cal mol-1 to the free energy of a PE molecule in a hydrated liquid-crystalline phospholipid bilayer; this free-energy contribution is somewhat smaller, but still significant, for N-mono- and dimethylated PE's.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/1-palmitoyl-2-oleoylphosphatidyletha..., http://linkedlifedata.com/resource/pubmed/chemical/Carbazoles, http://linkedlifedata.com/resource/pubmed/chemical/Diphenylhexatriene, http://linkedlifedata.com/resource/pubmed/chemical/Fatty Acids, Monounsaturated, http://linkedlifedata.com/resource/pubmed/chemical/Fluorescent Dyes, http://linkedlifedata.com/resource/pubmed/chemical/Indoles, http://linkedlifedata.com/resource/pubmed/chemical/Lipid Bilayers, http://linkedlifedata.com/resource/pubmed/chemical/Phosphatidylcholines, http://linkedlifedata.com/resource/pubmed/chemical/Phosphatidylethanolamines, http://linkedlifedata.com/resource/pubmed/chemical/Phospholipids, http://linkedlifedata.com/resource/pubmed/chemical/Quaternary Ammonium Compounds
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
30
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7491-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Partitioning of fluorescent phospholipid probes between different bilayer environments. Estimation of the free energy of interlipid hydrogen bonding.
pubmed:affiliation
Department of Biochemistry, McGill University, Montréal, Québec, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't