{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T03:23:39Z","timestamp":1792466619846,"version":"4.5.0"},"reference-count":43,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,2,28]],"date-time":"2025-02-28T00:00:00Z","timestamp":1740700800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004836","name":"Danmarks Frie Forskningsfond","doi-asserted-by":"publisher","award":["1032-00033B"],"award-info":[{"award-number":["1032-00033B"]}],"id":[{"id":"10.13039\/501100004836","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100009708","name":"Novo Nordisk Fonden","doi-asserted-by":"publisher","award":["NNF17OC0028528"],"award-info":[{"award-number":["NNF17OC0028528"]}],"id":[{"id":"10.13039\/501100009708","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Infect. Microbiol."],"abstract":"<jats:p>The Gram-positive bacterium <jats:italic>Listeria monocytogenes<\/jats:italic> is a highly adaptable pathogen capable of causing severe foodborne infections, particularly in vulnerable populations. During infection, <jats:italic>L. monocytogenes<\/jats:italic> uses a variety of virulence factors to invade and multiply within host cells. The transcriptional regulator PrfA controls the expression of these virulence factors and is essential for the intracellular lifestyle of <jats:italic>L. monocytogenes<\/jats:italic>. Long-chain unsaturated free fatty acids (FFAs) have long been recognized for their antimicrobial activity and were recently shown to inhibit PrfA-dependent virulence gene expression in <jats:italic>L. monocytogenes<\/jats:italic>. To date, the antimicrobial and anti-virulent activities of FFAs have been primarily studied in laboratory strains. However, to fully evaluate their potential as anti-infective agents, it is essential to assess the effects of long-chain FFAs on clinically relevant isolates, including outbreak strains associated with high-fat food products. Here, we demonstrate that five different clinically relevant <jats:italic>L. monocytogenes<\/jats:italic> isolates are sensitive to the antimicrobial activity of long-chain unsaturated FFAs. Furthermore, at subinhibitory concentrations, these FFAs inhibit PrfA-regulated expression of virulence factors across all tested strains and reduce their invasive potential in non-phagocytic cells. These findings underscore the potential of long-chain unsaturated FFAs in developing new preventive strategies against <jats:italic>L. monocytogenes<\/jats:italic> strains associated with severe foodborne infections.<\/jats:p>","DOI":"10.3389\/fcimb.2025.1542165","type":"journal-article","created":{"date-parts":[[2025,2,28]],"date-time":"2025-02-28T07:02:14Z","timestamp":1740726134000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":3,"title":["Long-chain unsaturated free fatty acids reduce the host cell invasion of Listeria monocytogenes outbreak strains"],"prefix":"10.3389","volume":"15","author":[{"given":"Caroline","family":"Borreby","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thea Amalie","family":"Hvidtfeldt","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Magnus Ganer","family":"Jespersen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patricia","family":"T. dos Santos","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sofie Dam","family":"Houborg","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eva Maria Sternkopf","family":"Lilleb\u00e6k","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Kemp","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Birgitte H.","family":"Kallipolitis","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2025,2,28]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1093\/femsre\/fuad037","article-title":"Anti-infective activities of long-chain fatty acids against foodborne pathogens","volume":"47","author":"Borreby","year":"2023","journal-title":"FEMS Microbiol. 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