Effect of nanosecond pulsed electric field on Escherichia coli in water: inactivation and impact on protein changes

• Published in: Journal of applied microbiology 2014-09, Vol.117 (3), p.721-728
• Main Authors: Guionet, A, Joubert‐Durigneux, V, Packan, D, Cheype, C, Garnier, J.‐P, David, F, Zaepffel, C, Leroux, R.‐M, Teissié, J, Blanckaert, V
• Format: Article
• Language: English
• Subjects: Anti-Bacterial Agents - pharmacology; Bacteria; Biological and medical sciences; Biological treatment of waters; Biotechnology; Cell Membrane Permeability; E coli; Electric fields; electropermeabilization; Electroporation - instrumentation; Electroporation - methods; Environment and pollution; Escherichia coli; Escherichia coli - drug effects; Escherichia coli - metabolism; Escherichia coli Proteins - metabolism; food processing; Fundamental and applied biological sciences. Psychology; inactivation; Industrial applications and implications. Economical aspects; industry; Microbial Viability; Microbiology; pathogenicity; phenotype; Plasma; plate count; propidium; protein synthesis; Proteins; pulsed electric fields; two-dimensional gel electrophoresis; viability; waste water treatment; water; Water Microbiology
• ISSN: 1364-5072; 1365-2672
• DOI: 10.1111/jam.12558

AIMS: This article shows the effect of nanosecond pulsed electric field (nsPEF) on Escherichia coli, which could imply a durable change in protein expressions and then impacted the phenotype of surviving bacteria that might lead to increase pathogenicity. METHODS AND RESULTS: The effects of nsPEF on E. coli viability and membrane permeabilization were investigated. One log₁₀reduction in bacterial counts was achieved at field strength of 10⁷ V m⁻¹with a train of 500 successive pulses of 60 × 10⁻⁹ s. Incubation of germs after treatment with propidium iodide showed that membrane permeabilization was reversible. Possible protein changes of surviving bacteria were checked to assess potential phenotypical changes using two‐dimensional electrophoresis. In our study, after 40 generations, only UniProt #P39187 was up‐regulated with P ≤ 0·05 compared with the control and corresponded to the uncharacterized protein YtfJ. Antibiograms were used to check whether or not the pattern of cultivable bacteria after nsPEF deliveries changed. CONCLUSIONS: The results tend to show that nsPEFs are able to inactivate bacteria and have probably no serious impact in E. coli protein patterns. SIGNIFICANCE AND IMPACT OF THE STUDY: The use of nsPEF is a safe promising new nonthermal method for bacterial inactivation in the food processing and environmental industry.