{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T04:50:23Z","timestamp":1780462223932,"version":"3.54.1"},"reference-count":65,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2020,10,23]],"date-time":"2020-10-23T00:00:00Z","timestamp":1603411200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Schweizerischer Nationalfonds zur F&amp;#x00F6;rderung der Wissenschaftlichen Forschung","award":["407240_167068"],"award-info":[{"award-number":["407240_167068"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>The number of environmental antibiotic-resistant bacteria (ARB) has increased dramatically since the start of antibiotic mass production for broad bacterial infection treatment in 1944. Nowadays, ARB and their resistance-determining genes (ARGs) are readily detected in all environments, including the human food chain. A highly relevant food group in this context is fresh produce, frequent raw consumption of which facilitates direct transfer of ARB and ARGs to the consumer. Here, we investigate the persistence of an extended-spectrum \u03b2-lactamase (ESBL)-producing Escherichia coli (E. coli) pEK499 and its clinically most important ARG (blaCTX-M-15), after introduction via irrigation water or manure into a lettuce-growing system. Culturable ESBL-producing E. coli persisted longest in soil and when introduced via manure (until 9 weeks after introduction), while being undetectable on lettuce beyond day 7. In contrast, qPCR detection of blaCTX-M-15 was much more frequent: introduction via water significantly increased blaCTX-M-15 on lettuce until week 4, as opposed to manure, which affected the soil in the long-term (9 weeks) while leading to blaCTX-M-15 detection on lettuce until day 7 only. Our findings demonstrate long-term persistence of undesired ARB and ARG after their introduction via both irrigation and amendment. Such an understanding of the persistence kinetics of an ESBL-producing E. coli and plasmid-encoded blaCTX-M-15 aids the determination of critical actions in order to mitigate their transfer to the consumer.<\/jats:p>","DOI":"10.3390\/microorganisms8111646","type":"journal-article","created":{"date-parts":[[2020,10,26]],"date-time":"2020-10-26T02:34:54Z","timestamp":1603679694000},"page":"1646","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":35,"title":["Long-Term Persistence of blaCTX-M-15 in Soil and Lettuce after Introducing Extended-Spectrum \u03b2-Lactamase (ESBL)-Producing Escherichia coli via Manure or Water"],"prefix":"10.3390","volume":"8","author":[{"given":"Maria-Theresia","family":"Gekenidis","sequence":"first","affiliation":[{"name":"Microbiological Food Safety, Agroscope, 8820 W\u00e4denswil, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Serena","family":"Rigotti","sequence":"additional","affiliation":[{"name":"Microbiological Food Safety, Agroscope, 8820 W\u00e4denswil, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J\u00f6rg","family":"Hummerjohann","sequence":"additional","affiliation":[{"name":"Microbiological Food Safety, Agroscope, 3003 Liebefeld, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0789-1689","authenticated-orcid":false,"given":"Fiona","family":"Walsh","sequence":"additional","affiliation":[{"name":"Department of Biology, Maynooth University, W23 F2H6 Maynooth, Co. Kildare, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David","family":"Drissner","sequence":"additional","affiliation":[{"name":"Department of Life Sciences, Albstadt-Sigmaringen University, 72488 Sigmaringen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,23]]},"reference":[{"key":"ref_1","unstructured":"Motarjemi, Y., Todd, E., and Moy, G. (2014). Microbial safety of fresh fruits and vegetables. Encyclopedia of Food Safety, Elsevier."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1532","DOI":"10.1080\/10408398.2013.777021","article-title":"Most common foodborne pathogens and mycotoxins on fresh produce: A review of recent outbreaks","volume":"56","author":"Yeni","year":"2015","journal-title":"Crit. Rev. Food Sci. 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