{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T16:03:03Z","timestamp":1790438583461,"version":"4.1.0"},"reference-count":28,"publisher":"Public Library of Science (PLoS)","issue":"7","license":[{"start":{"date-parts":[[2022,7,13]],"date-time":"2022-07-13T00:00:00Z","timestamp":1657670400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"JSPS Grants-in-Aid for Scientific Research","award":["19H03466, 19K22523, and 22H02869"],"award-info":[{"award-number":["19H03466, 19K22523, and 22H02869"]}]},{"DOI":"10.13039\/100007449","name":"the Takeda Science Foundation","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100007449","id-type":"DOI","asserted-by":"crossref"}]},{"name":"the Ichiro Kanehara Foundation"},{"name":"the Ryobi Teien Memory Foundation"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:p>The <jats:italic>mlaA<\/jats:italic> gene encodes a lipoprotein to maintain an outer membrane lipid asymmetry in gram-negative bacteria. Although the role of <jats:italic>mlaA<\/jats:italic> in bacterial virulence has been studied in several bacterial species, there are no reports of its role in <jats:italic>E<\/jats:italic>. <jats:italic>coli<\/jats:italic> virulence. In this study, we found that knockout of <jats:italic>mlaA<\/jats:italic> in <jats:italic>E<\/jats:italic>. <jats:italic>coli<\/jats:italic> increased its virulence against silkworms. The <jats:italic>mlaA-<\/jats:italic>knockout mutant was sensitive to several antibiotics and detergents, but resistant to vancomycin and chlorhexidine. The <jats:italic>mlaA<\/jats:italic>-knockout mutant grew faster than the parent strain in the presence of silkworm hemolymph. The <jats:italic>mlaA<\/jats:italic>-knockout mutant also produced a larger amount of outer membrane vesicles than the parent strain. These findings suggest that <jats:italic>mlaA<\/jats:italic> knockout causes <jats:italic>E<\/jats:italic>. <jats:italic>coli<\/jats:italic> resistance to specific antimicrobial substances and increases outer membrane vesicle production, thereby enhancing <jats:italic>E<\/jats:italic>. <jats:italic>coli<\/jats:italic> virulence properties in the silkworm infection model.<\/jats:p>","DOI":"10.1371\/journal.pone.0270166","type":"journal-article","created":{"date-parts":[[2022,7,13]],"date-time":"2022-07-13T17:34:28Z","timestamp":1657733668000},"page":"e0270166","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":22,"title":["Knockout of mlaA increases Escherichia coli virulence in a silkworm infection model"],"prefix":"10.1371","volume":"17","author":[{"given":"Haruka","family":"Nasu","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Riko","family":"Shirakawa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kazuyuki","family":"Furuta","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2895-3386","authenticated-orcid":true,"given":"Chikara","family":"Kaito","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2022,7,13]]},"reference":[{"issue":"1","key":"pone.0270166.ref001","doi-asserted-by":"crossref","first-page":"118","DOI":"10.1016\/0005-2736(76)90182-6","article-title":"Outer membrane of Salmonella typhimurium. 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