{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T09:06:41Z","timestamp":1769850401845,"version":"3.49.0"},"reference-count":48,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,12,23]],"date-time":"2021-12-23T00:00:00Z","timestamp":1640217600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000199","name":"U.S. Department of Agriculture","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100000199","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"<jats:p><jats:italic>Listeria monocytogenes<\/jats:italic> is a regulated foodborne pathogen that is known to cause listeriosis, a disease associated with high mortality rates in humans. Olive leaf extract (OLE) has been shown to act as a plant antimicrobial and inhibit the growth of pathogens, such as <jats:italic>L. monocytogenes<\/jats:italic>, although its mode of action has not been defined. To help identify the cellular mechanisms important for conveying these beneficial traits, RNA-Seq was used to study the transcriptome of <jats:italic>L. monocytogenes<\/jats:italic> upon exposure to a sublethal level of OLE. Results obtained from cells cultured both with and without OLE at two different time points (3.5-h and 24-h) revealed 661 genes that were differentially expressed. Of the differentially expressed genes (DEGs) identified, transcription was altered for 171 genes in response to the 3.5-h OLE treatment while 490 genes were altered in response to the 24-h OLE treatment. These DEGs included but were not limited to genes encoding for signal transduction, ATP-binding cassette (ABC) transporters, and the phosphotransferase system. Interestingly, several virulence-related genes were downregulated including an ABC transporter permease previously shown to negatively regulate biofilm formation, genes involved in flagella assembly and binding\/entry into host cells as well as those regulating acid resistance suggesting that OLE may decrease the virulence potential of <jats:italic>L. monocytogenes<\/jats:italic>. Furthermore, quantitative reverse-transcription PCR was used to validate the data obtained <jats:italic>via<\/jats:italic> RNA-Seq. Our study provides insight into the mode of action of OLE treatment against <jats:italic>L. monocytogenes<\/jats:italic> and may aid in identifying synergetic strategies to inhibit <jats:italic>L. monocytogenes<\/jats:italic> in food.<\/jats:p>","DOI":"10.3389\/fmicb.2021.782116","type":"journal-article","created":{"date-parts":[[2021,12,24]],"date-time":"2021-12-24T11:33:30Z","timestamp":1640345610000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Transcriptomics of Listeria monocytogenes Treated With Olive Leaf Extract"],"prefix":"10.3389","volume":"12","author":[{"given":"Yanhong","family":"Liu","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ting","family":"Fang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yujuan","family":"Suo","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shigang","family":"Gao","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gian Marco","family":"Baranzoni","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cheryl M.","family":"Armstrong","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2021,12,23]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1046\/j.1365-2958.2002.02723.x","article-title":"Formation of D-alanyl-lipoteichoic acid is required for adhesion and virulence of Listeria monocytogenes","volume":"43","author":"Abachin","year":"2002","journal-title":"Mol. 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