{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T16:34:11Z","timestamp":1785429251786,"version":"3.56.0"},"reference-count":14,"publisher":"American Society for Microbiology","issue":"6","license":[{"start":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T00:00:00Z","timestamp":1780358400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T00:00:00Z","timestamp":1780358400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.asm.org\/non-commercial-tdm-license"}],"funder":[{"DOI":"10.13039\/100010269","name":"Wellcome Trust","doi-asserted-by":"publisher","award":["106244\/Z\/14\/Z"],"award-info":[{"award-number":["106244\/Z\/14\/Z"]}],"id":[{"id":"10.13039\/100010269","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ineos Oxford Institute for Antimicrobial Research"}],"content-domain":{"domain":["journals.asm.org"],"crossmark-restriction":true},"short-container-title":["Microbiol Spectr"],"published-print":{"date-parts":[[2026,6,2]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title\/>\n                    <jats:p>\n                      SmTetX, a flavin-dependent monooxygenase from the opportunistic pathogen\n                      <jats:italic toggle=\"yes\">Stenotrophomonas maltophilia<\/jats:italic>\n                      , is structurally related to the tetracycline-degrading Tet(X) resistance enzymes, though displays substantial divergence in active site residues. Here, we provide evidence that recombinant SmTetX is a functional monooxygenase, but the enzyme does not appear to recognize tetracycline antibiotics as substrates and does not catalyze their degradation. Furthermore, SmTetX fails to confer tetracycline resistance when heterologously expressed in\n                      <jats:italic toggle=\"yes\">E. coli<\/jats:italic>\n                      . These findings indicate SmTetX is likely not a resistance determinant, presenting an opportunity to identify its physiological substrate and biological role.\n                    <\/jats:p>\n                    <jats:sec>\n                      <jats:title>IMPORTANCE<\/jats:title>\n                      <jats:p>\n                        The rapid dissemination of\n                        <jats:italic toggle=\"yes\">tet(X<\/jats:italic>\n                        ) resistance genes threatens the effectiveness of tetracycline antibiotics, including last-resort drugs such as tigecycline. Accurate assignment of functional Tet(X) homologs is therefore important for global antimicrobial resistance surveillance efforts and for selecting targets for the development of therapies that overcome Tet(X) resistance. Here, we demonstrate that SmTetX, a Tet(X)-like enzyme from\n                        <jats:italic toggle=\"yes\">Stenotrophomonas maltophilia<\/jats:italic>\n                        , is likely not able to confer resistance to tetracyclines, indicating that its role in tetracycline resistance may have been misattributed. These findings highlight the need for robust experimental validation of novel\n                        <jats:italic toggle=\"yes\">tet(X<\/jats:italic>\n                        ) genes identified through sequence homology.\n                      <\/jats:p>\n                    <\/jats:sec>\n                  <\/jats:sec>","DOI":"10.1128\/spectrum.00027-26","type":"journal-article","created":{"date-parts":[[2026,4,27]],"date-time":"2026-04-27T13:20:31Z","timestamp":1777296031000},"update-policy":"https:\/\/doi.org\/10.1128\/asmj-crossmark-policy-page","source":"Crossref","is-referenced-by-count":0,"title":["Evidence that SmTetX is not a tetracycline resistance determinant"],"prefix":"10.1128","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4416-4037","authenticated-orcid":false,"given":"Matthew J.","family":"Beech","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/052gg0110","id-type":"ROR","asserted-by":"publisher"}],"name":"Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford","place":["Oxford, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5462-7026","authenticated-orcid":false,"given":"Maria M.","family":"Trush","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/052gg0110","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Biology and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford","place":["Oxford, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-5717-2926","authenticated-orcid":false,"given":"Edmond C.","family":"Toma","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/052gg0110","id-type":"ROR","asserted-by":"publisher"}],"name":"Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford","place":["Oxford, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5578-6790","authenticated-orcid":false,"given":"Alistair J. M.","family":"Farley","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/052gg0110","id-type":"ROR","asserted-by":"publisher"}],"name":"Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford","place":["Oxford, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4315-4096","authenticated-orcid":false,"given":"Timothy R.","family":"Walsh","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/052gg0110","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Biology and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford","place":["Oxford, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0290-6565","authenticated-orcid":true,"given":"Christopher J.","family":"Schofield","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/052gg0110","id-type":"ROR","asserted-by":"publisher"}],"name":"Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford","place":["Oxford, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"235","reference":[{"key":"e_1_3_4_2_2","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.M409573200"},{"key":"e_1_3_4_3_2","doi-asserted-by":"publisher","DOI":"10.1128\/Spectrum.01164-21"},{"key":"e_1_3_4_4_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.scitotenv.2021.147613"},{"key":"e_1_3_4_5_2","doi-asserted-by":"publisher","DOI":"10.1128\/spectrum.00196-22"},{"key":"e_1_3_4_6_2","doi-asserted-by":"publisher","DOI":"10.1038\/s42003-022-03465-y"},{"key":"e_1_3_4_7_2","doi-asserted-by":"publisher","DOI":"10.1107\/S2053230X23005381"},{"key":"e_1_3_4_8_2","doi-asserted-by":"publisher","DOI":"10.1038\/nchembio.2376"},{"key":"e_1_3_4_9_2","doi-asserted-by":"publisher","DOI":"10.1186\/s12915-021-01199-7"},{"key":"e_1_3_4_10_2","doi-asserted-by":"publisher","DOI":"10.1007\/s00284-023-03524-5"},{"key":"e_1_3_4_11_2","doi-asserted-by":"publisher","DOI":"10.1093\/jac\/dkz200"},{"key":"e_1_3_4_12_2","doi-asserted-by":"publisher","DOI":"10.1039\/d5sc00964b"},{"key":"e_1_3_4_13_2","doi-asserted-by":"publisher","DOI":"10.1021\/acsinfecdis.8b00349"},{"key":"e_1_3_4_14_2","doi-asserted-by":"publisher","DOI":"10.1038\/s41564-019-0496-4"},{"key":"e_1_3_4_15_2","doi-asserted-by":"publisher","DOI":"10.1128\/Spectrum.00648-21"}],"container-title":["Microbiology Spectrum"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/spectrum.00027-26","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/spectrum.00027-26","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,17]],"date-time":"2026-06-17T13:11:24Z","timestamp":1781701884000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.asm.org\/doi\/10.1128\/spectrum.00027-26"}},"subtitle":[],"editor":[{"given":"Emily","family":"Weinert","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2026,6,2]]},"references-count":14,"journal-issue":{"issue":"6","published-print":{"date-parts":[[2026,6,2]]}},"alternative-id":["10.1128\/spectrum.00027-26"],"URL":"https:\/\/doi.org\/10.1128\/spectrum.00027-26","relation":{},"ISSN":["2165-0497"],"issn-type":[{"value":"2165-0497","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,2]]},"assertion":[{"value":"2026-01-12","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-03-30","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-04-27","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e00027-26"}}