Linked Life Data

2697747

Source:http://linkedlifedata.com/resource/pubmed/id/2697747

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1990-4-26
pubmed:abstractText
Addition of glucose or fructose to cells of Saccharomyces cerevisiae adapted to grow in the absence of glucose induced an acidification of the intracellular medium. This acidification appeared to be due to the phosphorylation of the sugar since: (i) glucose analogues which are not efficiently phosphorylated did not induce internal acidification; (ii) glucose addition did not cause internal acidification in a mutant deficient in all the three sugar-phosphorylating enzymes; (iii) fructose did not affect the intracellular pH in a double mutant having only glucokinase activity; (iv) glucose was as effective as fructose in inducing the internal pH drop in a mutant deficient in phosphoglucose isomerase activity; and (v) in strains deficient in two of the three sugar-phosphorylating activities, there was a good correlation between the specific glucose- or fructose-phosphorylating activity of cell extracts and the sugar-induced internal acidification. In addition, in whole cells any of the three yeast sugar kinases were capable of mediating the internal acidification described. Glucose-induced internal acidification was observed even when yeast cells were suspended in growth medium and in cells suspended in buffer containing K+, which supports the possible signalling function of the glucose-induced internal acidification. Evaluation of internal pH by following fluorescence changes of fluorescein-loaded cells indicated that the change in intracellular pH occurred immediately after addition of sugar. The apparent Km for glucose in this process was 2 mM. Changes in both the internal and external pH were determined and it was found that the internal acidification induced by glucose was followed by a partial alkalinization coincident with the initiation of H+ efflux. This reversal of acidification could be due to the activity of the H+-ATPase, since it was inhibited by diethylstilboestrol. Coincidence between internal alkalinization and the H+ efflux was also observed after addition of ethanol.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-1287
pubmed:author
pubmed:issnType
Print
pubmed:volume
135
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2413-22
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
The mechanism of intracellular acidification induced by glucose in Saccharomyces cerevisiae.
pubmed:affiliation
Departamento de Biología Funcional, Universidad de Oviedo, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't