{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,17]],"date-time":"2026-10-17T20:22:50Z","timestamp":1792268570921,"version":"4.4.0"},"reference-count":33,"publisher":"Wiley","issue":"10","license":[{"start":{"date-parts":[[2019,8,7]],"date-time":"2019-08-07T00:00:00Z","timestamp":1565136000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Protein Science"],"published-print":{"date-parts":[[2019,10]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Corrinoids are essential cofactors of enzymes involved in the C<jats:sub>1<\/jats:sub> metabolism of anaerobes. The active, super\u2010reduced [Co<jats:sup>I<\/jats:sup>] state of the corrinoid cofactor is highly sensitive to autoxidation. In <jats:italic>O<\/jats:italic>\u2010demethylases, the oxidation to inactive [Co<jats:sup>II<\/jats:sup>] is reversed by an ATP\u2010dependent electron transfer catalyzed by the activating enzyme (AE). The redox potential changes of the corrinoid cofactor, which occur during this reaction, were studied by potentiometric titration coupled to UV\/visible spectroscopy. By applying europium(II)\u2013diethylenetriaminepentaacetic acid (DTPA) as a reductant, we were able to determine the midpoint potential of the [Co<jats:sup>II<\/jats:sup>]\/[Co<jats:sup>I<\/jats:sup>] couple of the protein\u2010bound corrinoid cofactor in the absence and presence of AE and\/or ATP. The data revealed that the transfer of electrons from a physiological donor to the corrinoid as the electron\u2010accepting site is achieved by increasing the potential of the corrinoid cofactor from \u2212530\u2009\u00b1\u200915\u2009mV to \u2212250\u2009\u00b1\u200910 mV (<jats:italic>E<\/jats:italic><jats:sub>SHE<\/jats:sub>, pH 7.5). The first 50 to 100\u2009mV of the shift of the redox potential seem to be caused by the interaction of nucleotide\u2010bound AE with the corrinoid protein or its cofactor. The remaining 150\u2013200\u2009mV had to be overcome by the chemical energy of ATP hydrolysis. The experiments revealed that Eu(II)\u2013DTPA, which was already known as a powerful reducing agent, is a suitable electron donor for titration experiments of low\u2010potential redox centers. Furthermore, the results of this study will contribute to the understanding of thermodynamically unfavorable electron transfer processes driven by the power of ATP hydrolysis.<\/jats:p>","DOI":"10.1002\/pro.3699","type":"journal-article","created":{"date-parts":[[2019,7,30]],"date-time":"2019-07-30T06:39:03Z","timestamp":1564468743000},"page":"1902-1908","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Redox potential changes during ATP\u2010dependent corrinoid reduction determined by redox titrations with europium(II)\u2013DTPA"],"prefix":"10.1002","volume":"28","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4043-6979","authenticated-orcid":false,"given":"Hendrike","family":"D\u00fcrichen","sequence":"first","affiliation":[{"name":"Institute of Microbiology, Department of Applied and Ecological Microbiology Friedrich Schiller University Jena  Jena Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8996-5882","authenticated-orcid":false,"given":"Gabriele","family":"Diekert","sequence":"additional","affiliation":[{"name":"Institute of Microbiology, Department of Applied and Ecological Microbiology Friedrich Schiller University Jena  Jena Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5117-317X","authenticated-orcid":false,"given":"Sandra","family":"Studenik","sequence":"additional","affiliation":[{"name":"Institute of Microbiology, Department of Applied and Ecological Microbiology Friedrich Schiller University Jena  Jena Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2019,8,7]]},"reference":[{"key":"e_1_2_7_2_1","doi-asserted-by":"publisher","DOI":"10.1023\/A:1022525626986"},{"key":"e_1_2_7_3_1","doi-asserted-by":"publisher","DOI":"10.1021\/bi00449a019"},{"key":"e_1_2_7_4_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00203-005-0001-8"},{"key":"e_1_2_7_5_1","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.mi.26.100172.001035"},{"key":"e_1_2_7_6_1","doi-asserted-by":"publisher","DOI":"10.1007\/BF00871640"},{"key":"e_1_2_7_7_1","doi-asserted-by":"publisher","DOI":"10.1007\/s002030050479"},{"key":"e_1_2_7_8_1","doi-asserted-by":"publisher","DOI":"10.1128\/JB.01104-08"},{"key":"e_1_2_7_9_1","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.biochem.78.070907.103812"},{"key":"e_1_2_7_10_1","doi-asserted-by":"publisher","DOI":"10.1002\/cbic.201402270"},{"key":"e_1_2_7_11_1","doi-asserted-by":"publisher","DOI":"10.1098\/rsta.2004.1539"},{"key":"e_1_2_7_12_1","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.M807392200"},{"key":"e_1_2_7_13_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1117126109"},{"key":"e_1_2_7_14_1","doi-asserted-by":"publisher","DOI":"10.1021\/bi001645e"},{"key":"e_1_2_7_15_1","doi-asserted-by":"publisher","DOI":"10.1006\/jmbi.2000.4496"},{"key":"e_1_2_7_16_1","doi-asserted-by":"publisher","DOI":"10.1126\/science.1115653"},{"key":"e_1_2_7_17_1","doi-asserted-by":"publisher","DOI":"10.1021\/bi300571z"},{"key":"e_1_2_7_18_1","doi-asserted-by":"publisher","DOI":"10.1038\/ncomms5626"},{"key":"e_1_2_7_19_1","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.M117.801548"},{"key":"e_1_2_7_20_1","doi-asserted-by":"publisher","DOI":"10.1039\/b308188e"},{"key":"e_1_2_7_21_1","doi-asserted-by":"publisher","DOI":"10.1021\/bi800437g"},{"key":"e_1_2_7_22_1","doi-asserted-by":"publisher","DOI":"10.1021\/ja1067178"},{"key":"e_1_2_7_23_1","doi-asserted-by":"publisher","DOI":"10.1111\/mmi.12582"},{"key":"e_1_2_7_24_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.56.3.979"},{"key":"e_1_2_7_25_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.75.6.2699"},{"key":"e_1_2_7_26_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1742-4658.2004.04498.x"},{"key":"e_1_2_7_27_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1432-1033.1997.00840.x"},{"key":"e_1_2_7_28_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.241375598"},{"key":"e_1_2_7_29_1","doi-asserted-by":"publisher","DOI":"10.1021\/bi00087a005"},{"key":"e_1_2_7_30_1","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.274.17.11513"},{"key":"e_1_2_7_31_1","doi-asserted-by":"publisher","DOI":"10.1021\/ja00425a039"},{"key":"e_1_2_7_32_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ccr.2015.11.001"},{"key":"e_1_2_7_33_1","first-page":"47","volume-title":"Fermente, Hormone, Vitamine","author":"Friedrich W","year":"1975"},{"key":"e_1_2_7_34_1","doi-asserted-by":"publisher","DOI":"10.1016\/0003-2697(76)90527-3"}],"container-title":["Protein Science"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fpro.3699","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/pro.3699","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/pro.3699","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/pro.3699","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,9,9]],"date-time":"2023-09-09T12:21:53Z","timestamp":1694262113000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/pro.3699"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,8,7]]},"references-count":33,"journal-issue":{"issue":"10","published-print":{"date-parts":[[2019,10]]}},"alternative-id":["10.1002\/pro.3699"],"URL":"https:\/\/doi.org\/10.1002\/pro.3699","archive":["Portico"],"relation":{},"ISSN":["0961-8368","1469-896X"],"issn-type":[{"value":"0961-8368","type":"print"},{"value":"1469-896X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,8,7]]},"assertion":[{"value":"2019-05-21","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2019-07-22","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2019-08-07","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}