Large-scale phenotypic and genomic analysis of Listeria monocytogenes reveals diversity in the sensitivity to quaternary ammonium compounds but not to peracetic acid

Authors	IVANOVA Mirena KRAGH Martin Laage SZARVAS Judit TOSUN Elif Seyda HOLMUD Natacha Friis GMEINER Alexander AMAR Corinne GULDIMANN Claudia HUYNH TuAnh N KARPÍŠKOVÁ Renata ROTA Carmen GOMEZ Diego ABOAGYE Eurydice ETTER Andrea CENTORAME Patrizia TORRESI Marina ELISABETTA De Angelis Maria POMILIO Francesco OKHOLM Anders Hauge XIAO Yinghua KLETA Sylvia LUETH Stefanie PIETZKA Ariane KOVACEVIC Jovana PAGOTTO Franco RYCHLI Kathrin ZDOVC Irena PAPIC Bojan HEIR Even LANGSRUD Solveig MORETRO Trond BROWN Phillip KATHARIOU Sophia ROGER Stephan TASARA Taurai DALGAARD Paw NJAGE Patrick Murigu Kamau FAGERLUND Annette AARESTRUP Frank HANSEN Lisbeth Truelstrup LEEKITCHAROENPHON Pimlapas
Year of publication	2025
Type	Peer-reviewed scientific article
Magazine / Source	Applied and Environmental Microbiology
MU Faculty or unit	Faculty of Medicine
Citation
web	https://journals.asm.org/doi/10.1128/aem.01829-24
Doi	https://doi.org/10.1128/aem.01829-24
Keywords	Listeria monocytogenes; food industry; disinfectants; quaternary ammonium compounds; peracetic acid
Description	Listeria monocytogenes presents a significant concern for the food industry due to its ability to persist in the food processing environment. One of the factors contributing to its persistence is decreased sensitivity to disinfectants. Our objective was to assess the diversity of L. monocytogenes sensitivity to food industry disinfectants by testing the response of 1,671 L. monocytogenes isolates to quaternary ammonium compounds (QACs) and 414 isolates to peracetic acid (PAA) using broth microdilution and growth curve analysis assays, respectively, and to categorize the isolates into sensitive and tolerant. A high phenotype-genotype concordance (95%) regarding tolerance to QACs was obtained by screening the genomes for the presence of QAC tolerance-associated genes bcrABC, emrE, emrC, and qacH. Based on this high concordance, we assessed the QAC genes’ dissemination among publicly available L. monocytogenes genomes (n = 39,196). Overall, QAC genes were found in 23% and 28% of the L. monocytogenes collection in this study and in the global data set, respectively. bcrABC and qacH were the most prevalent genes, with bcrABC being the most detected QAC gene in the USA, while qacH dominated in Europe. No significant differences (P > 0.05) in the PAA tolerance were detected among isolates belonging to different lineages, serogroups, clonal complexes, or isolation sources, highlighting limited variation in the L. monocytogenes sensitivity to this disinfectant. The present work represents the largest testing of L. monocytogenes sensitivity to important food industry disinfectants at the phenotypic and genomic level, revealing diversity in the tolerance to QACs while all isolates showed similar sensitivity to PAA.