Transcriptomic approach and membrane fatty acid analysis to study the response mechanisms of Escherichia coli to thyme essential oil, carvacrol, 2-(E)-hexanal and citral exposure (original) (raw)

The application of essential oils and their components as food preservatives is promising but requires a deeper understanding of their mechanisms of action. This study aims to evaluate the effects of thyme essential oil, carvacrol, citral and 2-(E)-hexenal, on whole-genome gene expression (the transcriptome), as well as the fatty acids composition of the cell membranes of Escherichia coli K12. Therefore, we studied the response against 1 hour of exposure to sublethal concentrations of natural antimicrobials, of exponentially growing Escherichia coli K12, using DNA microarray technology and a gas chromatographic method. The results show that treatment with a sublethal concentration of the antimicrobials strongly affects global gene expression in E. coli for all antimicrobials used. Major changes in the expression of genes involved in metabolic pathways as well as in fatty acid biosynthesis and protection against oxidative stress were evidenced. Moreover, the sub-lethal treatments res...