title: Emergence of pulsed electric fields resistance in Salmonella enterica serovar Typhimurium SL1344.
abstract: In this investigation we selected and isolated a culture derived from Salmonella enterica serovar Typhimurium SL1344 with stable increased resistance to pulsed electric fields (PEF) after repeated rounds of PEF treatment and outgrowth of survivors. The resulting culture showed a higher resistance to PEF treatments under different treatment conditions. The acquisition of PEF resistance was only observed in stationary phase cells. The cytoplasmic membrane of the resistant variant showed a higher resilience against PEF treatments, since a lower permeabilization degree was observed after PEF treatments, in comparison to the parental strain. Resistance to PEF was also accompanied by a higher tolerance to acidic pH, hydrogen peroxide and ethanol, but not to heat. The occurrence of a PEF resistant variant in S. enterica serovar Typhimurium SL1344 emphasizes the need to further study the mechanisms of inactivation and resistance by PEF for an adequate design of safe treatments.
authors: Food Technology, Faculty of Veterinary of Zaragoza, Zaragoza, Spain.
authors: N
authors: N
authors: Sagarzazu
authors: G
authors: G
authors: Cebrián
authors: R
authors: R
authors: Pagán
authors: S
authors: S
authors: Condón
authors: P
authors: P
authors: Mañas
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D004560:Electricity; D000431:Ethanol / Q000494:pharmacology; D006358:Hot Temperature; D006861:Hydrogen Peroxide / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D012486:Salmonella typhimurium / Q000187:drug effects / Q000502:physiology*; D016019:Survival Analysis
chemical_list: D000900:Anti-Bacterial Agents; D000431:Ethanol; D006861:Hydrogen Peroxide
keywords: Pulsed electric fields (PEF); Resistant variant; Salmonella Typhimurium