{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T17:00:41Z","timestamp":1790182841974,"version":"4.1.0"},"reference-count":41,"publisher":"Oxford University Press (OUP)","issue":"10","license":[{"start":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T00:00:00Z","timestamp":1787961600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004189","name":"Max Planck Society","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100004189","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["390838134"],"award-info":[{"award-number":["390838134"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002345","name":"University of T\u00fcbingen","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100002345","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,9,18]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Bacterial nitrate (NO3\u2212) -reducing Fe(II) oxidation is often regarded as an autotrophic process, although its long-term sustainability is rarely demonstrated. Here, we assessed whether Geobacter metallireducens (ATCC 53774) can sustain chemolithoautotrophic nitrate-reducing Fe(II) oxidation. Cultures were incubated with Fe(II) and NO3\u2212 as electron donor and acceptor, respectively, and CO2 as the sole carbon source. Negative controls contained either (1) electron acceptor, (2) donor or (3) no substrates. We found that first-generation cultures transferred from a washed NO3\u2212\/acetate-grown preculture oxidized 21.0\u00b11.3% (2.09\u00b10.14\u00a0mM) of 10\u00a0mM Fe(II) and reduced 5.2\u00b13.9% (0.20\u00b10.15\u00a0mM) of 4\u00a0mM NO3\u2212. Nitrite remained below the detection limit and ammonium increase was not observed while total N2O accumulated up to 31.34\u00b11.90\u00a0\u00b5M. However, following transfers under organic-free conditions did not sustain Fe(II) oxidation. Further, we did not observe a decrease in nitrate, although we found low N2O formation of total 9.10\u00b10.42\u00a0\u00b5M and 14.10\u00b13.90\u00a0\u00b5M in later generations. These results demonstrate that G. metallireducens does not sustain autotrophic nitrate-reducing Fe(II) oxidation, although it may contribute to coupled Fe(II) oxidation and nitrate reduction in organic environments.<\/jats:p>","DOI":"10.1093\/femsec\/fiag098","type":"journal-article","created":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T15:06:21Z","timestamp":1788015981000},"source":"Crossref","is-referenced-by-count":0,"title":["<i>Geobacter metallireducens<\/i>\n                    \u2014evaluation of its sustainability in nitrate-reducing Fe(II) oxidation under autotrophic conditions"],"prefix":"10.1093","volume":"102","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-6909-797X","authenticated-orcid":false,"given":"Stefanie","family":"Becker","sequence":"first","affiliation":[{"name":"University of T\u00fcbingen Geomicrobiology, Department of Geosciences, , Schnarrenbergstrasse 94\u201296, D-72076 T\u00fcbingen 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