{"title":"蛋白质顺磁核磁共振光谱中优异的铁(II)结合标签","authors":"Mo-Han Li, Xing Zhang, Bin-Bin Pan, Xun-Cheng Su","doi":"10.1021/acs.inorgchem.4c05233","DOIUrl":null,"url":null,"abstract":"Most first series of transition metal ions have one or more unpaired electrons and show great variations in the paramagnetic property. The magnetic anisotropy of some transition metal ions, including Co(II), as well as lanthanide ions [Ln(III)], has been well examined in proteins by NMR. In contrast, few examples of Fe(II) complexes reporting the magnetic anisotropy were analyzed in proteins, except for the ones containing a heme motif or iron–sulfur clusters. Here, we showed that [2,2′:6′,2″-terpyridine]-6,6″-dicarboxylic acid (TDA) is an excellent iron-binding ligand. It forms a stable iron complex in aqueous solution and demonstrates distinct iron-binding properties. TDA forms a 1:1 stable complex with both Fe(II) and Fe(III), but Fe(II) presents a high-spin state in the complex. The TDA moiety can be site-specifically attached to a protein, and its protein conjugate generates sizable pseudocontact shifts (PCSs) in complex with Fe(II), which are larger than those of commonly used metal binding tags. In contrast, the protein–TDA–Fe(III) complex produces negligible paramagnetic relaxation enhancement (PRE) effects in the protein signals, indicating a low-spin state of Fe(III) in the protein-TDA complex. The high stability of the protein-TDA-Fe(II) complex allows one to measure accurate PCSs in cell lysate even in the presence of other transition metal ions and an excess of GSH.","PeriodicalId":40,"journal":{"name":"Inorganic Chemistry","volume":"1 1","pages":""},"PeriodicalIF":4.7000,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Excellent Fe(II) Binding Tag in Protein Paramagnetic NMR Spectroscopy\",\"authors\":\"Mo-Han Li, Xing Zhang, Bin-Bin Pan, Xun-Cheng Su\",\"doi\":\"10.1021/acs.inorgchem.4c05233\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Most first series of transition metal ions have one or more unpaired electrons and show great variations in the paramagnetic property. The magnetic anisotropy of some transition metal ions, including Co(II), as well as lanthanide ions [Ln(III)], has been well examined in proteins by NMR. In contrast, few examples of Fe(II) complexes reporting the magnetic anisotropy were analyzed in proteins, except for the ones containing a heme motif or iron–sulfur clusters. Here, we showed that [2,2′:6′,2″-terpyridine]-6,6″-dicarboxylic acid (TDA) is an excellent iron-binding ligand. It forms a stable iron complex in aqueous solution and demonstrates distinct iron-binding properties. TDA forms a 1:1 stable complex with both Fe(II) and Fe(III), but Fe(II) presents a high-spin state in the complex. The TDA moiety can be site-specifically attached to a protein, and its protein conjugate generates sizable pseudocontact shifts (PCSs) in complex with Fe(II), which are larger than those of commonly used metal binding tags. In contrast, the protein–TDA–Fe(III) complex produces negligible paramagnetic relaxation enhancement (PRE) effects in the protein signals, indicating a low-spin state of Fe(III) in the protein-TDA complex. The high stability of the protein-TDA-Fe(II) complex allows one to measure accurate PCSs in cell lysate even in the presence of other transition metal ions and an excess of GSH.\",\"PeriodicalId\":40,\"journal\":{\"name\":\"Inorganic Chemistry\",\"volume\":\"1 1\",\"pages\":\"\"},\"PeriodicalIF\":4.7000,\"publicationDate\":\"2025-04-14\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Inorganic Chemistry\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://doi.org/10.1021/acs.inorgchem.4c05233\",\"RegionNum\":2,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"CHEMISTRY, INORGANIC & NUCLEAR\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Inorganic Chemistry","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1021/acs.inorgchem.4c05233","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, INORGANIC & NUCLEAR","Score":null,"Total":0}
Excellent Fe(II) Binding Tag in Protein Paramagnetic NMR Spectroscopy
Most first series of transition metal ions have one or more unpaired electrons and show great variations in the paramagnetic property. The magnetic anisotropy of some transition metal ions, including Co(II), as well as lanthanide ions [Ln(III)], has been well examined in proteins by NMR. In contrast, few examples of Fe(II) complexes reporting the magnetic anisotropy were analyzed in proteins, except for the ones containing a heme motif or iron–sulfur clusters. Here, we showed that [2,2′:6′,2″-terpyridine]-6,6″-dicarboxylic acid (TDA) is an excellent iron-binding ligand. It forms a stable iron complex in aqueous solution and demonstrates distinct iron-binding properties. TDA forms a 1:1 stable complex with both Fe(II) and Fe(III), but Fe(II) presents a high-spin state in the complex. The TDA moiety can be site-specifically attached to a protein, and its protein conjugate generates sizable pseudocontact shifts (PCSs) in complex with Fe(II), which are larger than those of commonly used metal binding tags. In contrast, the protein–TDA–Fe(III) complex produces negligible paramagnetic relaxation enhancement (PRE) effects in the protein signals, indicating a low-spin state of Fe(III) in the protein-TDA complex. The high stability of the protein-TDA-Fe(II) complex allows one to measure accurate PCSs in cell lysate even in the presence of other transition metal ions and an excess of GSH.
期刊介绍:
Inorganic Chemistry publishes fundamental studies in all phases of inorganic chemistry. Coverage includes experimental and theoretical reports on quantitative studies of structure and thermodynamics, kinetics, mechanisms of inorganic reactions, bioinorganic chemistry, and relevant aspects of organometallic chemistry, solid-state phenomena, and chemical bonding theory. Emphasis is placed on the synthesis, structure, thermodynamics, reactivity, spectroscopy, and bonding properties of significant new and known compounds.