{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,12]],"date-time":"2026-07-12T03:30:16Z","timestamp":1783827016702,"version":"3.55.0"},"reference-count":27,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,4,20]],"date-time":"2026-04-20T00:00:00Z","timestamp":1776643200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Bioeng. Biotechnol."],"abstract":"<jats:p>\n                    The increasing production of biodiesel has led to a surplus of glycerol, a polluting by-product in need of valorization. In this study, we demonstrate that\n                    <jats:italic>Citrobacter telavivensis<\/jats:italic>\n                    T1.2D-1, an extremophile bacterium isolated from the Iberian Pyrite Belt, effectively converts glycerol into valuable compounds via dark anaerobic fermentation. Genomic and bioinformatic analyses confirmed the presence of the\n                    <jats:italic>dha<\/jats:italic>\n                    and\n                    <jats:italic>pdu<\/jats:italic>\n                    operons, responsible for 1,3-propanediol (1,3-PDO) synthesis, and the\n                    <jats:italic>hyc<\/jats:italic>\n                    operon and\n                    <jats:italic>fdhF<\/jats:italic>\n                    gene involved in hydrogen (H\n                    <jats:sub>2<\/jats:sub>\n                    ) production. Batch fermentations revealed that optimal yields of both H\n                    <jats:sub>2<\/jats:sub>\n                    (0.94\u00a0mol\n                    <jats:sup>.<\/jats:sup>\n                    mol-glycerol\n                    <jats:sup>-1<\/jats:sup>\n                    ) and 1,3-PDO (0.66\u00a0mol\u2027mol-glycerol\n                    <jats:sup>-1<\/jats:sup>\n                    ) were achieved at 25\u00a0\u00b0C using 2\u00a0g\u00a0L\n                    <jats:sup>-1<\/jats:sup>\n                    of supplied glycerol. Optimum yield of ethanol (1\u00a0mol\u2027mol-glycerol\n                    <jats:sup>-1<\/jats:sup>\n                    ) was achieved using 12.5\u00a0g\u00a0L\n                    <jats:sup>-1<\/jats:sup>\n                    of supplied glycerol. Interestingly, 1,3-PDO and H\n                    <jats:sub>2<\/jats:sub>\n                    production inversely correlated with ethanol formation, suggesting metabolic competition. Antibiotic sensitivity profiling revealed susceptibility to multiple antibiotics, supporting future genetic engineering efforts. We suggest opperating with reactors at low concentrations to produce 1,3-PDO and H\n                    <jats:sub>2<\/jats:sub>\n                    with high yields, and at medium concentrations to generate ethanol. Our findings support\n                    <jats:italic>C. telavivensis<\/jats:italic>\n                    T1.2D-1 as a promising venue for the sustainable biotechnological production of biohydrogen and bio-based 1,3-PDO from glycerol, offering a dual solution to both energy demands and industrial waste management.\n                  <\/jats:p>","DOI":"10.3389\/fbioe.2026.1778768","type":"journal-article","created":{"date-parts":[[2026,4,20]],"date-time":"2026-04-20T05:25:07Z","timestamp":1776662707000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Sustainable co-production of 1,3-PDO, ethanol and H2 from glycerol via dark fermentation by Citrobacter telavivensis T1.2D-1 isolated from the deep subsurface"],"prefix":"10.3389","volume":"14","author":[{"given":"In\u00e9s","family":"Ochoa-Arizu","sequence":"first","affiliation":[{"name":"Departamento de Biolog\u00eda Molecular, Universidad Aut\u00f3noma de Madrid","place":["Madrid, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adri\u00e1n","family":"Mart\u00ednez-Bonilla","sequence":"additional","affiliation":[{"name":"Departamento de Biolog\u00eda Molecular, Universidad Aut\u00f3noma de Madrid","place":["Madrid, Spain"]},{"name":"IUBM-UAM and Centro de Biolog\u00eda Molecular Severo Ochoa (CSIC-UAM)","place":["Madrid, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nuria","family":"Rodr\u00edguez","sequence":"additional","affiliation":[{"name":"Department of Planetology and Habitability, Centro de Astrobiolog\u00eda (CAB), CSIC-INTA","place":["Madrid, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patricia","family":"Rojas","sequence":"additional","affiliation":[{"name":"Departamento de Biolog\u00eda Molecular, Universidad Aut\u00f3noma de Madrid","place":["Madrid, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ricardo","family":"Amils","sequence":"additional","affiliation":[{"name":"Departamento de Biolog\u00eda Molecular, Universidad Aut\u00f3noma de Madrid","place":["Madrid, Spain"]},{"name":"IUBM-UAM and Centro de Biolog\u00eda Molecular Severo Ochoa (CSIC-UAM)","place":["Madrid, Spain"]},{"name":"Department of Planetology and Habitability, Centro de Astrobiolog\u00eda (CAB), CSIC-INTA","place":["Madrid, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jos\u00e9 Luis","family":"Sanz","sequence":"additional","affiliation":[{"name":"Departamento de Biolog\u00eda Molecular, Universidad Aut\u00f3noma de Madrid","place":["Madrid, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto G.","family":"Fair\u00e9n","sequence":"additional","affiliation":[{"name":"Department of Planetology and Habitability, Centro de Astrobiolog\u00eda (CAB), CSIC-INTA","place":["Madrid, Spain"]},{"name":"Department of Astronomy, Cornell University","place":["Ithaca, NY, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David","family":"Ruano-Gallego","sequence":"additional","affiliation":[{"name":"Departamento de Biolog\u00eda Molecular, Universidad Aut\u00f3noma de Madrid","place":["Madrid, Spain"]},{"name":"IUBM-UAM and Centro de Biolog\u00eda Molecular Severo Ochoa (CSIC-UAM)","place":["Madrid, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,4,20]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"5001","DOI":"10.1007\/s00253-013-4726-z","article-title":"Glycerol assimilation and production of 1,3-propanediol by Citrobacter amalonaticus Y19","volume":"97","author":"Ainala","year":"2013","journal-title":"Appl. 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