Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2010-6-29
pubmed:abstractText
The mechanism of hexose transport into plasma membrane vesicles isolated from mature sugarbeet leaves (Beta vulgaris L.) was investigated. The initial rate of glucose uptake into the vesicles was stimulated approximately fivefold by imposing a transmembrane pH gradient (DeltapH), alkaline inside, and approximately fourfold by a negative membrane potential (DeltaPsi), generated as a K(+)-diffusion potential, negative inside. The -fold stimulation was directly related to the relative DeltapH or DeltaPsi gradient imposed, which were determined by the uptake of acetate or tetraphenylphosphonium, respectively. DeltaPsi- and DeltapH-dependent glucose uptake showed saturation kinetics with a K(m) of 286 micromolar for glucose. Other hexose molecules (e.g. 2-deoxy-d-glucose, 3-O-methyl-d-glucose, and d-mannose) were also accumulated into plasma membrane vesicles in a DeltapH-dependent manner. Inhibition constants of a number of compounds for glucose uptake were determined. Effective inhibitors of glucose uptake included: 3-O-methyl-d-glucose, 5-thio-d-glucose, d-fructose, d-galactose, and d-mannose, but not 1-O-methyl-d-glucose, d- and l-xylose, l-glucose, d-ribose, and l-sorbose. Under all conditions of proton motive force magnitude and glucose and sucrose concentration tested, there was no effect of sucrose on glucose uptake. Thus, hexose transport on the sugarbeet leaf plasma membrane was by a H(+)-hexose symporter, and the carrier and possibly the energy source were not shared by the plasma membrane H(+)-sucrose symporter.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-11607110, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-16666703, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-1849009, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-1881917, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-1883208, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-2209537, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-2407475, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-2490366, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-2540699, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-2599110, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-2666404, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-2745421, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-3745177, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-4772688, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669023-942051
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Jul
pubmed:issn
0032-0889
pubmed:author
pubmed:issnType
Print
pubmed:volume
99
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
945-51
pubmed:dateRevised
2010-9-15
pubmed:year
1992
pubmed:articleTitle
In Vitro Analysis of the H-Hexose Symporter on the Plasma Membrane of Sugarbeets (Beta vulgaris L.).
pubmed:affiliation
FB Biologie, Universität Kaiserslautern, Postfach 3049, D-6750 Kaiserslautern, Federal Republic of Germany.
pubmed:publicationType
Journal Article