Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1988-8-5
pubmed:abstractText
1. Various ways of computing the proton stoichiometry of glycine absorption were examined in relation to the problem of distinguishing the proton flow (i) through the symport from the basal proton flow (ii) outside it. By depolarizing the plasma membrane, i will tend to inhibit ii. 2. A series of 23 yeast (Saccharomyces carlsbergensis) preparations grown with proline or glutamate were used, some of which were starved in the presence of glucose. Consequently, after ATP depletion, the rate of glycine uptake from a 0.2 mM solution varied through the series from 3 to 14 nmol.min-1.mg-1. Basal proton uptake in the absence of glycine was fairly constant at 3-4 nmol.min-1.mg-1. 3. After addition of glycine, the number of extra equivalents of protons entering the yeast with each amino acid equivalent in 30 s was 0.5 at the lowest rate of glycine absorption and 1.8 equivalents at the fastest rate. However, total proton absorption in 30 s increased in direct proportion to the amount of glycine absorbed. The proportionality factor, indicative of the carrier stoichiometry, was 2.25 +/- 0.13 (23) S.E.M. The effective basal proton uptake was negligibly small. 4. Progress of proton and glycine absorption by each yeast preparation in the period up to 180 s fitted the mathematical model described in the preceding paper by Eddy, Hopkins & Johnson [(1988) Biochem. J. 251, 111-114]. The analysis led to two estimates of the constant ratio of the inflow of protons to the inflow of glycine that would apply when the basal proton flow vanished. These further estimates of the carrier stoichiometry were also near 2, being 2.07 +/- 0.24 (6) and 2.22 +/- 0.07 (17).
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/2839155-238506, http://linkedlifedata.com/resource/pubmed/commentcorrection/2839155-2839154, http://linkedlifedata.com/resource/pubmed/commentcorrection/2839155-2998345, http://linkedlifedata.com/resource/pubmed/commentcorrection/2839155-4587071, http://linkedlifedata.com/resource/pubmed/commentcorrection/2839155-5129266, http://linkedlifedata.com/resource/pubmed/commentcorrection/2839155-5474888, http://linkedlifedata.com/resource/pubmed/commentcorrection/2839155-6093875, http://linkedlifedata.com/resource/pubmed/commentcorrection/2839155-6226314, http://linkedlifedata.com/resource/pubmed/commentcorrection/2839155-6331188, http://linkedlifedata.com/resource/pubmed/commentcorrection/2839155-728087, http://linkedlifedata.com/resource/pubmed/commentcorrection/2839155-942391
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0264-6021
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
251
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
115-9
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
The intrinsic as opposed to the apparent stoichiometry of the glycine-proton symport of the yeast Saccharomyces carlsbergensis.
pubmed:affiliation
Department of Biochemistry and Applied Molecular Biology, University of Manchester Institute of Science and Technology, U.K.
pubmed:publicationType
Journal Article