{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T19:53:27Z","timestamp":1791230007242,"version":"4.1.0"},"reference-count":28,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2022,6,15]],"date-time":"2022-06-15T00:00:00Z","timestamp":1655251200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000928","name":"Welch Endowed Chair in Biochemistry to TTUHSC","doi-asserted-by":"publisher","award":["BI-0028"],"award-info":[{"award-number":["BI-0028"]}],"id":[{"id":"10.13039\/100000928","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>NaCT mediates citrate uptake in the liver cell line HepG2. When these cells were exposed to iron (Fe3+), citrate uptake\/binding as monitored by the association of [14C]-citrate with cells increased. However, there was no change in NaCT expression and function, indicating that NaCT was not responsible for this Fe3+-induced citrate uptake\/binding. Interestingly however, the process exhibited substrate selectivity and saturability as if the process was mediated by a transporter. Notwithstanding these features, subsequent studies demonstrated that the iron-induced citrate uptake\/binding did not involve citrate entry into cells; instead, the increase was due to the formation of citrate-Fe3+ chelate that adsorbed to the cell surface. Surprisingly, the same phenomenon was observed in culture wells without HepG2 cells, indicating the adsorption of the citrate-Fe3+ chelate to the plastic surface of culture wells. We used this interesting phenomenon as a simple screening technique for new iron chelators with the logic that if another iron chelator is present in the assay system, it would compete with citrate for binding to Fe3+ and prevent the formation and adsorption of citrate-Fe3+ to the culture well. This technique was validated with the known iron chelators deferiprone and deferoxamine, and with the bacterial siderophore 2,3-dihydroxybenzoic acid and the catechol carbidopa.<\/jats:p>","DOI":"10.3390\/ijms23126657","type":"journal-article","created":{"date-parts":[[2022,6,15]],"date-time":"2022-06-15T22:17:01Z","timestamp":1655331421000},"page":"6657","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Binding of Citrate-Fe3+ to Plastic Culture Dishes, an Artefact Useful as a Simple Technique to Screen for New Iron Chelators"],"prefix":"10.3390","volume":"23","author":[{"given":"Jiro","family":"Ogura","sequence":"first","affiliation":[{"name":"Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA"},{"name":"Graduate School of Pharmaceutical Sciences, Yamagata University, Yamagata 990-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8807-2417","authenticated-orcid":false,"given":"Toshihiro","family":"Sato","sequence":"additional","affiliation":[{"name":"Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA"},{"name":"Department of Pharmaceutical Sciences, Tohoku University Hospital, Sendai 980-8574, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kei","family":"Higuchi","sequence":"additional","affiliation":[{"name":"Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA"},{"name":"Department of Pharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9230-0144","authenticated-orcid":false,"given":"Sathish","family":"Sivaprakasam","sequence":"additional","affiliation":[{"name":"Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5934-2695","authenticated-orcid":false,"given":"Jonathan","family":"Kopel","sequence":"additional","affiliation":[{"name":"Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yangzom D.","family":"Bhutia","sequence":"additional","affiliation":[{"name":"Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vadivel","family":"Ganapathy","sequence":"additional","affiliation":[{"name":"Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"39469","DOI":"10.1074\/jbc.M207072200","article-title":"Structure, function, and expression pattern of a novel sodium-coupled citrate transporter (NaCT) cloned from mammalian brain","volume":"277","author":"Inoue","year":"2002","journal-title":"J. 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