Linked Life Data

1835654

Source:http://linkedlifedata.com/resource/pubmed/id/1835654

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
47
pubmed:dateCreated
1992-1-3
pubmed:abstractText
The effect of a protonophoric uncoupler (CCCP) on the different cellular compartments was investigated in yeast grown aerobically on lactate. These cells were incubated in a resting cell medium under three conditions; in aerobiosis with lactate or glucose or in anaerobiosis with glucose as energetic substrate. For each condition, in vivo 31P NMR was used to measure pH gradients across vacuolar and plasma membrane and phosphorylated compound levels. Respiratory rate (aerobic conditions) and TPP+ uptake were measured independently. Concerning the polyphosphate metabolism, spontaneous NMR-detected polyphosphate breakdown occurred, in anaerobiosis and in the absence of CCCP. In contrast, in aerobiosis, polyphosphate hydrolysis was induced by addition of either CCCP or a vacuolar membrane ATPase-specific inhibitor, bafilomycin A1. Moreover, polyphosphates were totally absent in a null vacuolar ATPase activity mutant. The vacuolar polyphosphate content depended on two factors: vacuolar pH value, strictly linked to the vacuolar H(+)-ATPase activity, and inorganic phosphate concentration. CCCP was more efficient in dissipating the proton electrochemical gradient across vacuolar and mitochondrial membranes than across the plasma membrane. This discrepancy can be essentially explained by a difference of stimulability of each proton pump involved. As long as the energetic state (measured by NDP + NTP content) remains high, the plasma membrane proton ATPase is able to compensate the proton leak. Moreover, this ATPase contributes only partially to the generation of delta pH. The maintenance of the delta pH across the plasma membrane, that of the energetic state, and the cellular TPP+ uptake depend on the nature of the ATP-producing process.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
26
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11212-20
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:1835654-Adenosine Triphosphatases, pubmed-meshheading:1835654-Aerobiosis, pubmed-meshheading:1835654-Anti-Bacterial Agents, pubmed-meshheading:1835654-Antifungal Agents, pubmed-meshheading:1835654-Carbonyl Cyanide m-Chlorophenyl Hydrazone, pubmed-meshheading:1835654-Energy Metabolism, pubmed-meshheading:1835654-Fermentation, pubmed-meshheading:1835654-Glucose, pubmed-meshheading:1835654-Hydrogen-Ion Concentration, pubmed-meshheading:1835654-Kinetics, pubmed-meshheading:1835654-Macrolides, pubmed-meshheading:1835654-Magnetic Resonance Spectroscopy, pubmed-meshheading:1835654-Onium Compounds, pubmed-meshheading:1835654-Organophosphorus Compounds, pubmed-meshheading:1835654-Oxygen Consumption, pubmed-meshheading:1835654-Saccharomyces cerevisiae, pubmed-meshheading:1835654-Vacuoles
pubmed:year
1991
pubmed:articleTitle
Differential sensitivity of the cellular compartments of Saccharomyces cerevisiae to protonophoric uncoupler under fermentative and respiratory energy supply.
pubmed:affiliation
Institut de Biochimie Cellulaire et de Neurochimie du CNRS, Université de Bordeaux II, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't