{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T18:07:50Z","timestamp":1780596470771,"version":"3.54.1"},"reference-count":30,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2019,3,6]],"date-time":"2019-03-06T00:00:00Z","timestamp":1551830400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000070","name":"National Institute of Biomedical Imaging and Bioengineering","doi-asserted-by":"publisher","award":["P41 EB001980"],"award-info":[{"award-number":["P41 EB001980"]}],"id":[{"id":"10.13039\/100000070","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000065","name":"National Institute of Neurological Disorders and Stroke","doi-asserted-by":"publisher","award":["R01 NS081936"],"award-info":[{"award-number":["R01 NS081936"]}],"id":[{"id":"10.13039\/100000065","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Bleser Endowed Chair in Neurology","award":["NA"],"award-info":[{"award-number":["NA"]}]},{"name":"Baumann Research Endowment","award":["NA"],"award-info":[{"award-number":["NA"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>In a previous study on chromate toxicity, an increase in the 2Fe2S electron paramagnetic resonance (EPR) signal from mitochondria was found upon addition of chromate to human bronchial epithelial cells and bovine airway tissue ex vivo. This study was undertaken to show that a chromate-induced increase in the 2Fe2S EPR signal is a general phenomenon that can be used as a low-temperature EPR method to determine the maximum concentration of 2Fe2S centers in mitochondria. First, the low-temperature EPR method to determine the concentration of 2Fe2S clusters in cells and tissues is fully developed for other cells and tissues. The EPR signal for the 2Fe2S clusters N1b in Complex I and\/or S1 in Complex II and the 2Fe2S cluster in xanthine oxidoreductase in rat liver tissue do not change in intensity because these clusters are already reduced; however, the EPR signals for N2, the terminal cluster in Complex I, and N4, the cluster preceding the terminal cluster, decrease upon adding chromate. More surprising to us, the EPR signals for N3, the cluster preceding the 2Fe2S cluster in Complex I, also decrease upon adding chromate. Moreover, this method is used to obtain the concentration of the 2Fe2S clusters in white blood cells where the 2Fe2S signal is mostly oxidized before treatment with chromate and becomes reduced and EPR detectable after treatment with chromate. The increase of the g = 1.94 2Fe2S EPR signal upon the addition of chromate can thus be used to obtain the relative steady-state concentration of the 2Fe2S clusters and steady-state concentration of Complex I and\/or Complex II in mitochondria.<\/jats:p>","DOI":"10.3390\/ijms20051143","type":"journal-article","created":{"date-parts":[[2019,3,7]],"date-time":"2019-03-07T10:52:22Z","timestamp":1551955942000},"page":"1143","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Treatment of Cells and Tissues with Chromate Maximizes Mitochondrial 2Fe2S EPR Signals"],"prefix":"10.3390","volume":"20","author":[{"given":"William E.","family":"Antholine","sequence":"first","affiliation":[{"name":"Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI 53226, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeannette","family":"Vasquez-Vivar","sequence":"additional","affiliation":[{"name":"Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI 53226, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brendan J.","family":"Quirk","sequence":"additional","affiliation":[{"name":"Departments of Neurology and Pediatrics, Medical College of Wisconsin, Milwaukee, WI 53226, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Harry T.","family":"Whelan","sequence":"additional","affiliation":[{"name":"Departments of Neurology and Pediatrics, Medical College of Wisconsin, Milwaukee, WI 53226, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8734-2657","authenticated-orcid":false,"given":"Pui Kei","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jong-In","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charles R.","family":"Myers","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, Medical College Wisconsin, Wauwatosa, WI 53226, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,3,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1903","DOI":"10.1016\/j.freeradbiomed.2010.09.020","article-title":"The pro-oxidant chromium(VI) inhibits mitochondrial complex I, complex II and aconitase in the bronchial epithelium: EPR markers for Fe-S proteins","volume":"49","author":"Myers","year":"2010","journal-title":"Free Radic. 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