title: Oleic acid delays and modulates the transition from respiratory to fermentative metabolism in Saccharomyces cerevisiae after exposure to glucose excess.
abstract: This work aimed to study the transition from respiratory to fermentative metabolism in Saccharomyces cerevisiae CEN.PK 113-7D and more specifically to evaluate the implication of the acetyl-coenzymeA-derived carbon transport from cytosol to mitochondria in the onset of the metabolic shift. The strategy consisted in introducing, during aerobic glucose-limited chemostat (D = 0.16 h(-1)), [corrected] a local perturbation around the step to be studied by the addition of cosubstrate and in analyzing the consequences of such a perturbation on the metabolic transition. Oleic acid and L: -carnitine were among the tested cosubstrates because they were known to stimulate enzymes implicated in the acetyl-coenzymeA transport between the different cell compartments, such as the carnitine acetyl transferases. The metabolic transition was then comparatively quantified in sole glucose and in glucose/oleic acid chemostats in presence/absence of L: -carnitine after a pulse of glucose. Feeding the culture with oleic acid (D (ole) = 0.0041 and 0.0073 h(-1)) [corrected] led to a delay in the onset of the metabolic shift (up to 15 min), a 33% decrease in the ethanol production and a redirection of the carbon flux toward biomass production. The data clearly showed a modulation of the carbon distribution among respiration and fermentation, in favor of a decrease in the "short-term" Crabtree effect by the oleic acid.
authors.affiliation: UMR5504, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, CNRS, INRA, INSA, 135 Avenue de Rangueil, 31077, Toulouse Cedex, France.
authors.forename: David
authors.initials: D
authors.lastname: Feria-Gervasio
authors.forename: Jean-Roch
authors.initials: JR
authors.lastname: Mouret
authors.forename: Nathalie
authors.initials: N
authors.lastname: Gorret
authors.forename: Gérard
authors.initials: G
authors.lastname: Goma
authors.forename: Stéphane E
authors.initials: SE
authors.lastname: Guillouet
mesh_terms: D000105:Acetyl Coenzyme A / Q000378:metabolism; D000332:Aerobiosis; D018533:Biomass; D002244:Carbon / Q000378:metabolism; D002331:Carnitine / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D000431:Ethanol / Q000378:metabolism; D005285:Fermentation; D005947:Glucose / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism; D008954:Models, Biological; D019301:Oleic Acid / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*
chemical_list: D019301:Oleic Acid; D000431:Ethanol; D000105:Acetyl Coenzyme A; D002244:Carbon; D005947:Glucose; D002331:Carnitine