Anti-listeria Activities of Linalool and Its Mechanism Revealed by Comparative Transcriptome Analysis

Abstract

Listeria monocytogenes, which causes serious foodborne infections and public health problems worldwide, is one of the most important foodborne pathogens. Linalool has been identified as an antimicrobial agent against some microorganism, but its mechanism of action is currently unclear. Here, we investigated the efficacy of linalool against L. monocytogenes while planktonic and as a biofilm and explored potential mechanisms of action. Linalool exhibited strong anti-listeria activity in the planktonic stage. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations revealed seven stages were classified of cells at microscopic level. Mesosome-like structures were observed for the first time in L. monocytogenes after linalool treatment. Linalool also showed significant anti-biofilm activity through both dispersal and killing of cells in the biofilm based on confocal scanning laser microscopy (CLSM) and SEM imaging, crystal violet staining, XTT and COMSTAT assays. Moreover, comparative transcriptome analysis demonstrated many potential mechanisms of action for linalool and some important pathways were screened out through the analysis of GO enrichment and KEGG. Our study provides evidence that linalool exhibits a strong antimicrobial activity against both the planktonic and biofilm forms of L. monocytogenes and gives insight into its mechanism of action.

In vitro Activity of Robenidine Analog NCL195 in Combination With Outer Membrane Permeabilizers Against Gram-Negative Bacterial Pathogens and Impact on Systemic Gram-Positive Bacterial Infection in Mice

“…TEM images show membrane morphology changes and the presence of mesosome-like membrane structures in NCL195-treated but not in untreated bacteria. The presence of mesosomes is possibly a consequence of cell membrane perturbation through disruption of the membrane potential, consistent with the effects of other antibiotic treatments reported by other workers (Friedrich et al, 2000;Li et al, 2008;Morita et al, 2015;Gao et al, 2019).…”

Simultaneous Hydrodistillation-Steam Distillation of Rosmarinus officinalis, Lavandula angustifolia and Citrus aurantium from Morocco, Major Terpenes: Impact on Biological Activities

“…The richness of the tested combination in 1,8-cineole, linalool, and linalyl acetate can explain the successful antibiofilm activity observed against both the Gram negative E. coli and the Gram positive S. aureus and the resistant MRSA 15. The ability of these components to successfully affect biofilm formation of pathogenic bacteria have been reported [ 59 , 60 , 61 , 62 , 63 , 64 ]. Interesting, chlorohexidine (0.2%, v / v ) (positive control) induced the biofilm formation of S. aureus ATCC 6538, in contrast to E. coli DSM 1077 and MRSA 15, for which a reduced biofilm formation was observed ( Figure 5 ).…”

New Insight into the Chemical Composition, Antimicrobial and Synergistic Effects of the Moroccan Endemic Thymus atlanticus (Ball) Roussine Essential Oil in Combination with Conventional Antibiotics

“…Similarly, the bicyclic monoterpene borneol is also a powerful and broad-spectrum antimicrobial agent able to alter the membrane structural and functional integrity [ 17 ]. In addition, other volatile compounds present in lower percentages can also contribute to the biological activity of the EO, including γ -terpinene, linalool and thymol [ 18 , 19 , 20 ]. Concerning the resistance of P. aeruginosa , it is well known that a multidrug-resistant bacterium uses many different mechanisms to counteract the antimicrobial drugs [ 21 ].…”