title: Slow heat rate increases yeast thermotolerance by maintaining plasma membrane integrity.
abstract: Thermal resistance of Saccharomyces cerevisiae was found to be drastically dependent on the kinetics of heat perturbation. Yeasts were found to be more resistant to a plateau of 1 h at 50 degrees C after a slope of temperature increase (slow and linear temperature increments) than after a shock (sudden temperature change). Thermotolerance was mainly acquired between 40-50 degrees C during a heat slope, i.e., above the maximal temperature of growth. The death of the yeasts subjected to a heat shock might be related to the loss of membrane integrity: intracellular contents extrusion, i.e., membrane permeabilization, was found to precede cell death. However, the permeabilization did not precede cell death during a heat slope and, therefore, membrane permeabilization was a consequence rather than a cause of cell death. During a slow temperature increase, yeasts which remain viable may have time to adapt their plasma membrane and thus maintain membrane integrity.
authors.affiliation: Laboratoire de Génie des Procédés Alimentaires et Biotechnologiques, ENSBANA, 1 Esplanade Erasme, 21000 Dijon, France.
authors.forename: I
authors.initials: I
authors.lastname: Martínez de Marañón
authors.forename: N
authors.initials: N
authors.lastname: Chaudanson
authors.forename: N
authors.initials: N
authors.lastname: Joly
authors.forename: P
authors.initials: P
authors.lastname: Gervais
mesh_terms: D002412:Cations / Q000032:analysis; D002462:Cell Membrane / Q000378:metabolism; D002463:Cell Membrane Permeability; D006358:Hot Temperature; D007700:Kinetics; D012441:Saccharomyces cerevisiae / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D002412:Cations