Effect of sub-lethal chemical disinfection on the biofilm forming ability, resistance to antibiotics and expression of virulence genes of Salmonella Enteritidis biofilm-surviving cells.
Maria João Leal RomeuDiana RodriguesJoana AzeredoPublished in: Biofouling (2020)
Although disinfection procedures are widely implemented in food environments, bacteria can survive and present increased virulence/resistance. Since little is known about these phenomena regarding biofilms, this study aimed to investigate the effect of chemical disinfection on biofilm-derived cells of Salmonella Enteritidis. Using a reference strain (NCTC 13349) and a food isolate (350), biofilm susceptibility to benzalkonium chloride (BAC), sodium hypochlorite (SH) and hydrogen peroxide (HP) was evaluated and biofilms were exposed to sub-lethal concentrations of each disinfectant. Biofilm-derived cells were characterized for their biofilm forming ability, antibiotic resistance and expression of virulence-associated genes. Except for a few instances, disinfectant exposure did not alter antibiotic susceptibility. However, SH and HP exposure enhanced the biofilm forming ability of Salmonella Enteritidis NCTC 13349. After BAC and HP exposure, biofilm-derived cells presented a down-regulation of rpoS. Exposure to BAC also revealed an up-regulation of invA, avrA and csgD on Salmonella Enteritidis NCTC 13349. The results obtained suggest that biofilm-derived cells that survive disinfection may represent an increased health risk.
Keyphrases
- pseudomonas aeruginosa
- staphylococcus aureus
- candida albicans
- biofilm formation
- induced apoptosis
- escherichia coli
- cell cycle arrest
- drinking water
- hydrogen peroxide
- cystic fibrosis
- health risk
- nitric oxide
- endoplasmic reticulum stress
- poor prognosis
- cell death
- single cell
- listeria monocytogenes
- gene expression
- dna methylation
- climate change
- long non coding rna
- pi k akt