{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T00:17:11Z","timestamp":1791505031467,"version":"4.3.4"},"update-to":[{"DOI":"10.1371\/journal.ppat.1009357","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2021,3,4]],"date-time":"2021-03-04T00:00:00Z","timestamp":1614816000000}}],"reference-count":52,"publisher":"Public Library of Science (PLoS)","issue":"2","license":[{"start":{"date-parts":[[2021,2,22]],"date-time":"2021-02-22T00:00:00Z","timestamp":1613952000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000199","name":"USDA","doi-asserted-by":"crossref","award":["2016-10255"],"award-info":[{"award-number":["2016-10255"]}],"id":[{"id":"10.13039\/100000199","id-type":"DOI","asserted-by":"crossref"}]},{"name":"NIH\/USDA NIFA","award":["2014-67015-21697"],"award-info":[{"award-number":["2014-67015-21697"]}]}],"content-domain":{"domain":["www.plospathogens.org"],"crossmark-restriction":false},"short-container-title":["PLoS Pathog"],"abstract":"<jats:p>Successful intestinal infection by<jats:italic>Salmonella<\/jats:italic>requires optimized invasion of the gut epithelium, a function that is energetically costly.<jats:italic>Salmonella<\/jats:italic>have therefore evolved to intricately regulate the expression of their virulence determinants by utilizing specific environmental cues. Here we show that a powerful repressor of<jats:italic>Salmonella<\/jats:italic>invasion, a<jats:italic>cis-<\/jats:italic>2 unsaturated long chain fatty acid, is present in the murine large intestine. Originally identified in<jats:italic>Xylella fastidiosa<\/jats:italic>as a diffusible signal factor for quorum sensing, this fatty acid directly interacts with HilD, the master transcriptional regulator of<jats:italic>Salmonella<\/jats:italic>, and prevents<jats:italic>hilA<\/jats:italic>activation, thus inhibiting<jats:italic>Salmonella<\/jats:italic>invasion. We further identify the fatty acid binding region of HilD and show it to be selective and biased in favour of signal factors with a<jats:italic>cis<\/jats:italic>-2 unsaturation over other intestinal fatty acids. Single mutation of specific HilD amino acids to alanine prevented fatty acid binding, thereby alleviating their repressive effect on invasion. Together, these results highlight an exceedingly sensitive mechanism used by<jats:italic>Salmonella<\/jats:italic>to colonize its host by detecting and exploiting specific molecules present within the complex intestinal environment.<\/jats:p>","DOI":"10.1371\/journal.ppat.1009357","type":"journal-article","created":{"date-parts":[[2021,2,22]],"date-time":"2021-02-22T18:36:29Z","timestamp":1614018989000},"page":"e1009357","update-policy":"https:\/\/doi.org\/10.1371\/journal.ppat.corrections_policy","source":"Crossref","is-referenced-by-count":39,"title":["A diffusible signal factor of the intestine dictates Salmonella invasion through its direct control of the virulence activator HilD"],"prefix":"10.1371","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4530-0029","authenticated-orcid":true,"given":"Rimi","family":"Chowdhury","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0943-8602","authenticated-orcid":true,"given":"Paulina D.","family":"Pavinski Bitar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1271-3847","authenticated-orcid":true,"given":"Ivan","family":"Keresztes","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4930-4879","authenticated-orcid":true,"given":"Anthony M.","family":"Condo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3740-9163","authenticated-orcid":true,"given":"Craig","family":"Altier","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2021,2,22]]},"reference":[{"issue":"6","key":"ppat.1009357.ref001","article-title":"Magnesium Sensing Regulates Intestinal Colonization of Enterohemorrhagic Escherichia coli O157:H7","volume":"11","author":"Y Liu","year":"2020","journal-title":"Mbio"},{"issue":"1","key":"ppat.1009357.ref002","doi-asserted-by":"crossref","DOI":"10.1128\/mBio.02122-17","article-title":"The Biochemistry of Sensing: Enteric Pathogens Regulate Type III Secretion in Response to Environmental and Host Cues","volume":"9","author":"NJ De 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