{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,10]],"date-time":"2026-03-10T18:21:01Z","timestamp":1773166861735,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2021,7,18]],"date-time":"2021-07-18T00:00:00Z","timestamp":1626566400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100009139","name":"Deutsches Zentrum f\u00fcr Infektionsforschung","doi-asserted-by":"publisher","award":["TTU 09.912"],"award-info":[{"award-number":["TTU 09.912"]}],"id":[{"id":"10.13039\/100009139","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Tobramycin is a broad-spectrum aminoglycoside antibiotic agent. The compound is obtained from the base-catalyzed hydrolysis of carbamoyltobramycin (CTB), which is naturally produced by the actinomycete Streptoalloteichus tenebrarius. However, the strain uses the same precursors to synthesize several structurally related aminoglycosides. Consequently, the production yields of tobramycin are low, and the compound\u2019s purification is very challenging, costly, and time-consuming. In this study, the production of the main undesired product, apramycin, in the industrial isolate Streptoalloteichus tenebrarius 2444 was decreased by applying the fermentation media M10 and M11, which contained high concentrations of starch and dextrin. Furthermore, the strain was genetically engineered by the inactivation of the aprK gene (\u2206aprK), resulting in the abolishment of apramycin biosynthesis. In the next step of strain development, an additional copy of the tobramycin biosynthetic gene cluster (BGC) was introduced into the \u2206aprK mutant. Fermentation by the engineered strain (\u2206aprK_1-17L) in M11 medium resulted in a 3- to 4-fold higher production than fermentation by the precursor strain (\u2206aprK). The phenotypic stability of the mutant without selection pressure was validated. The use of the engineered S. tenebrarius 2444 facilitates a step-saving, efficient, and, thus, more sustainable production of the valuable compound tobramycin on an industrial scale.<\/jats:p>","DOI":"10.3390\/molecules26144343","type":"journal-article","created":{"date-parts":[[2021,7,18]],"date-time":"2021-07-18T21:16:48Z","timestamp":1626643008000},"page":"4343","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Engineering of Streptoalloteichus tenebrarius 2444 for Sustainable Production of Tobramycin"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9841-3289","authenticated-orcid":false,"given":"Lena","family":"Mitousis","sequence":"first","affiliation":[{"name":"Interfaculty Institute of Microbiology and Infection Medicine (IMIT), Microbiology\/Biotechnology, University of T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"},{"name":"Cluster of Excellence \u2018Controlling Microbes to Fight Infections\u2019 (CMFI), University of T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hannes","family":"Maier","sequence":"additional","affiliation":[{"name":"Interfaculty Institute of Microbiology and Infection Medicine (IMIT), Microbiology\/Biotechnology, University of T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"},{"name":"Cluster of Excellence \u2018Controlling Microbes to Fight Infections\u2019 (CMFI), University of T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"},{"name":"German Centre for Infection Research (DZIF), Partner site T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Luka","family":"Martinovic","sequence":"additional","affiliation":[{"name":"Interfaculty Institute of Microbiology and Infection Medicine (IMIT), Microbiology\/Biotechnology, University of T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"},{"name":"Cluster of Excellence \u2018Controlling Microbes to Fight Infections\u2019 (CMFI), University of T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andreas","family":"Kulik","sequence":"additional","affiliation":[{"name":"Interfaculty Institute of Microbiology and Infection Medicine (IMIT), Microbiology\/Biotechnology, University of T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"},{"name":"Cluster of Excellence \u2018Controlling Microbes to Fight Infections\u2019 (CMFI), University of T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sigrid","family":"Stockert","sequence":"additional","affiliation":[{"name":"Interfaculty Institute of Microbiology and Infection Medicine (IMIT), Microbiology\/Biotechnology, University of T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"},{"name":"Cluster of Excellence \u2018Controlling Microbes to Fight Infections\u2019 (CMFI), University of T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wolfgang","family":"Wohlleben","sequence":"additional","affiliation":[{"name":"Interfaculty Institute of Microbiology and Infection Medicine (IMIT), Microbiology\/Biotechnology, University of T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"},{"name":"Cluster of Excellence \u2018Controlling Microbes to Fight Infections\u2019 (CMFI), University of T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"},{"name":"German Centre for Infection Research (DZIF), Partner site T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alfred","family":"Stiefel","sequence":"additional","affiliation":[{"name":"Huvepharma EOOD\/Biovet AD, 39 Petar Rakov Street, 4550 Peshtera, Bulgaria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3538-5142","authenticated-orcid":false,"given":"Ewa","family":"Musiol-Kroll","sequence":"additional","affiliation":[{"name":"Interfaculty Institute of Microbiology and Infection Medicine (IMIT), Microbiology\/Biotechnology, University of T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"},{"name":"Cluster of Excellence \u2018Controlling Microbes to Fight Infections\u2019 (CMFI), University of T\u00fcbingen, Auf der Morgenstelle 28, 72076 T\u00fcbingen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1565","DOI":"10.1002\/cbic.201500256","article-title":"Tobramycin Variants with Enhanced Ribosome-Targeting Activity","volume":"16","author":"Fosso","year":"2015","journal-title":"ChemBioChem"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"7896","DOI":"10.1038\/ncomms8896","article-title":"Chemically Related 4,5-Linked Aminoglycoside Antibiotics Drive Subunit Rotation in Opposite Directions","volume":"6","author":"Wasserman","year":"2015","journal-title":"Nat. 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