title: Importance of SigB for Listeria monocytogenes static and continuous-flow biofilm formation and disinfectant resistance.
abstract: Listeria monocytogenes is a food-borne pathogen that is able to form biofilms in food processing facilities. Biofilms are generally more resistant to antimicrobial agents, making it difficult to eradicate them during cleanup procedures. So far, little is known about the function of stress resistance mechanisms in biofilm formation and their resistance to disinfectants. In this study, we investigated the role of sigB, which encodes a major transcriptional regulator of stress response genes, in L. monocytogenes static and continuous-flow biofilm formation and its function in the resistance of biofilm cells to the disinfectants benzalkonium chloride and peracetic acid. Quantitative real-time PCR and promoter reporter studies showed that sigB is activated in static and continuous-flow biofilms. Biofilm formation studies using an in-frame sigB deletion mutant and complementation mutant showed that the presence of SigB is required to obtain wild-type levels of both static and continuous-flow biofilms. Finally, disinfection treatments of planktonically grown cells and cells dispersed from static and continuous-flow biofilms showed that SigB is involved in the resistance of both planktonic cells and biofilms to the disinfectants benzalkonium chloride and peracetic acid.
authors.affiliation: Laboratory of Food Microbiology, P.O. Box 8129, 6700 EV Wageningen, Netherlands. Stijn.vanderVeen@wur.nl
authors.forename: Stijn
authors.initials: S
authors.lastname: van der Veen
authors.forename: Tjakko
authors.initials: T
authors.lastname: Abee
mesh_terms: D018441:Biofilms / Q000187:drug effects / Q000254:growth & development*; D004202:Disinfectants / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D017353:Gene Deletion; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D017930:Genes, Reporter; D005816:Genetic Complementation Test; D008089:Listeria monocytogenes / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism*
chemical_list: D004202:Disinfectants; C480945:SigB protein, Listeria monocytogenes; D012808:Sigma Factor