{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,16]],"date-time":"2026-02-16T18:58:20Z","timestamp":1771268300148,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2015,6,3]],"date-time":"2015-06-03T00:00:00Z","timestamp":1433289600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"NIH","doi-asserted-by":"publisher","award":["R37AI021150-29"],"award-info":[{"award-number":["R37AI021150-29"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000738","name":"Department of Veterans Affairs","doi-asserted-by":"publisher","award":["Senior Research Career Scientist"],"award-info":[{"award-number":["Senior Research Career Scientist"]}],"id":[{"id":"10.13039\/100000738","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>MtrR is a well-characterized repressor of the Neisseria gonorrhoeae mtrCDE efflux pump operon. However, results from a previous transcriptional profiling study suggested that MtrR also represses or activates expression of at least sixty genes outside of the mtr locus. Evidence that MtrR can directly repress so-called \u201coff target\u201d genes has previously been reported; in particular, MtrR was shown to directly repress glnA, which encodes glutamine synthetase. In contrast, evidence for the ability of MtrR to directly activate expression of gonococcal genes has been lacking; herein, we provide such evidence. We now report that MtrR has the ability to directly activate expression of glnE, which encodes the dual functional adenyltransferase\/deadenylase enzyme GlnE that modifies GlnA resulting in regulation of its role in glutamine biosynthesis. With its capacity to repress expression of glnA, the results presented herein emphasize the diverse and often opposing regulatory properties of MtrR that likely contributes to the overall physiology and metabolism of N. gonorrhoeae.<\/jats:p>","DOI":"10.3390\/antibiotics4020188","type":"journal-article","created":{"date-parts":[[2015,6,3]],"date-time":"2015-06-03T11:29:39Z","timestamp":1433330979000},"page":"188-197","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["The Transcriptional Repressor, MtrR, of the mtrCDE Efflux Pump Operon of Neisseria gonorrhoeae Can Also Serve as an Activator of \u201coff Target\u201d Gene (glnE) Expression"],"prefix":"10.3390","volume":"4","author":[{"given":"Paul","family":"Johnson","sequence":"first","affiliation":[{"name":"Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta,  GA 30322, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"William","family":"Shafer","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta,  GA 30322, USA"},{"name":"The Emory Antibiotic Resistance Center, Emory University School of Medicine, Atlanta,  GA 30322, USA"},{"name":"Laboratories of Bacterial Pathogenesis, VA Medical Center, Decatur, GA 30033, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,6,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"28506","DOI":"10.1016\/S0021-9258(18)46956-6","article-title":"A protein that activates expression of a multidrug efflux transporter upon binding the transporter substrates","volume":"269","author":"Ahmed","year":"1994","journal-title":"J. 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