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Ionic and energetic changes at competence in the naturally transformable bacterium Streptococcus pneumoniae.

A Lopez·C Clavé·R Capeyrou·V Lafontan·M C Trombe
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Abstract

Addition of competence factor extracts to trigger competence in a culture of Streptococcus pneumoniae induced an increase in the intracellular pH and the Na+ content of the bacteria without any change in the K+ pool or in the membrane potential. These ionic shifts were concomitant with a stimulation of glycolysis that resulted in an enhanced ATP pool. Thus, in transforming conditions, at extracellular pH 7.8, competent bacteria presented a particularly high energetic state resulting from an increase in delta pH and in the ATP pool, associated with an enhanced Na+ content. These features are discussed in the context of homeostasis regulation in response to an environmental stimulus.

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Adenosine TriphosphateBenzoatesBenzoic AcidGlucoseHydrogen-Ion ConcentrationLactatesMagnetic Resonance SpectroscopyPotassiumSodiumStreptococcus pneumoniaeTransformation, GeneticJournal ArticleResearch Support, Non-U.S. Gov't

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A Lopez, C Clavé, R Capeyrou, V Lafontan, M C Trombe. 1989. Ionic and energetic changes at competence in the naturally transformable bacterium Streptococcus pneumoniae.. https://doi.org/10.1099/00221287-135-8-2189

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