Linked Life Data

2261488

Source:http://linkedlifedata.com/resource/pubmed/id/2261488

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1991-2-7
pubmed:abstractText
Transport-protein activities are often determined by procedures that involve isolation of liposomes containing the transported radioactive solute. We determined the activity of the human red cell glucose transporter in liposomes and, by similar procedures, internal volumes of liposomes. For these purposes, we isolated freeze-thawed liposomes loaded with [14C]glucose, either by filtration on cellulose-nitrate and cellulose-acetate filters, or by chromatography on Sephadex. The interaction of liposomes with filters caused substantial leakage of [14C]glucose. About half of the internal [14C]glucose was released on the filters from glucose-transporter liposomes with inhibited transport. Chromatography at high flow rate provided higher and more accurate values than did the filtration procedure. Leakage corrections could be made by use of flow-cell scintillation elution profiles. The ratios between the corrected chromatographic volume values and the filtration values were 1.4-3.0 for liposomes without protein, 2.4-4.0 for glucose-transporter liposomes and 3.6-7.9 for liposomes with several human red cell integral membrane proteins. The D-glucose equilibrium exchange with glucose-transporter liposomes at 50 mM D-glucose was 2.0 nmol D-glucose per microgram transporter per second as determined by use of chromatography at high flow rate. The filtration procedure gave only 0.6 nmol.microgram-1.s-1 due to the [14C]glucose leakage. In our experiments, the chromatographic procedure thus proved superior.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
14
pubmed:volume
1030
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
258-68
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Substantial glucose leakage from liposomes on filters and upon molecular-sieve chromatography in determinations of reconstituted glucose-transport activity and liposome volumes.
pubmed:affiliation
Department of Biochemistry, University of Uppsala, Sweden.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't