{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,27]],"date-time":"2026-05-27T13:41:50Z","timestamp":1779889310226,"version":"3.53.1"},"reference-count":27,"publisher":"Oxford University Press (OUP)","issue":"9","license":[{"start":{"date-parts":[[2021,6,21]],"date-time":"2021-06-21T00:00:00Z","timestamp":1624233600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"funder":[{"DOI":"10.13039\/100007225","name":"MOST","doi-asserted-by":"publisher","award":["108-2320-B-010-032-MY3"],"award-info":[{"award-number":["108-2320-B-010-032-MY3"]}],"id":[{"id":"10.13039\/100007225","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004663","name":"Ministry of Science and Technology of Taiwan","doi-asserted-by":"publisher","award":["CY11013"],"award-info":[{"award-number":["CY11013"]}],"id":[{"id":"10.13039\/501100004663","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005937","name":"Cheng Hsin General Hospital","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100005937","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2021,8,12]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>The SmeVWX efflux pump of Stenotrophomonas maltophilia contributes to menadione (MD) tolerance and resistance to chloramphenicol, quinolones and tetracycline. The components of the SmeVWX efflux pump are encoded by a five-gene operon, smeU1VWU2X. We have previously demonstrated that the smeU1VWU2X operon is intrinsically unexpressed and inducibly expressed by MD via a SoxR- and SmeRv-involved regulatory circuit in S. maltophilia KJ. We also inferred that there should be other regulator(s) involved in MD-mediated smeU1VWU2X expression in addition to SoxR and SmeRv.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Objectives<\/jats:title>\n                  <jats:p>To identify novel regulator(s) involved in the regulation of MD-mediated smeU1VWU2X expression and elucidate the regulatory circuit.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>A possible regulator candidate involved in the regulation of MD-mediated smeU1VWU2X expression was identified by a homologue search using the helix-turn-helix domain of SmeRv as a query. Gene expression was assessed using the promoter-xylE transcriptional fusion assay and quantitative RT\u2013PCR. The impact of the regulator on SmeVWX pump-mediated functions was investigated via mutant construction and functional tests (antibiotic susceptibility and MD tolerance).<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>AzoR (Smlt3089), a LysR-type transcriptional regulator, was investigated. In unstressed logarithmically grown cells, AzoR was abundantly expressed and functioned as a repressor, inhibiting the expression of the smeU1VWU2X operon. MD challenge attenuated azoR expression, thus derepressing the expression of the smeU1VWU2X operon in S. maltophilia KJ. AzoR down-regulation-mediated smeU1VWU2X expression was observed in quinolone-resistant and SmeVWX-overexpressing S. maltophilia clinical isolates.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>AzoR negatively regulates the expression of the smeU1VWU2X operon and SmeVWX pump-mediated antibiotic resistance in S. maltophilia.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1093\/jac\/dkab203","type":"journal-article","created":{"date-parts":[[2021,5,28]],"date-time":"2021-05-28T19:48:39Z","timestamp":1622231319000},"page":"2285-2293","source":"Crossref","is-referenced-by-count":8,"title":["Role of AzoR, a LysR-type transcriptional regulator, in SmeVWX pump-mediated antibiotic resistance in <i>Stenotrophomonas maltophilia<\/i>"],"prefix":"10.1093","volume":"76","author":[{"given":"Hsu-Feng","family":"Lu","sequence":"first","affiliation":[{"name":"Department of Clinical Pathology, Cheng Hsin General Hospital, Taipei, Taiwan"},{"name":"Department of Medical Laboratory Science and Biotechnology, Asia University, Taichung, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu-Chieh","family":"Tsai","sequence":"additional","affiliation":[{"name":"Department of Biotechnology and Laboratory Science in Medicine, National Yang-Ming University, Taipei, Taiwan"},{"name":"Division of Gastroenterology and Hepatology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2535-1758","authenticated-orcid":false,"given":"Li-Hua","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Pathology and Laboratory Medicine, Taipei Veterans General Hospital, Taipei, Taiwan"},{"name":"PhD Program in Medical Biotechnology, Taipei Medical University, Taipei, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yi-Tsung","family":"Lin","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan"},{"name":"School of Medicine, National Yang-Ming University, Taipei, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tsuey-Ching","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Biotechnology and Laboratory Science in Medicine, National Yang-Ming University, Taipei, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2021,6,21]]},"reference":[{"key":"2021081309090532300_dkab203-B1","doi-asserted-by":"crossref","first-page":"337","DOI":"10.1128\/CMR.00117-14","article-title":"The challenge of efflux-mediated antibiotic resistance in Gram-negative bacteria","volume":"28","author":"Li","year":"2015","journal-title":"Clin 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