Xicheng Liu, Changjian Ji, Rui Tao, Wenya Zheng, Mengxian Liu, Shiqing Bi, Qinghua Chang, Xiang-Ai Yuan, Mingbo Yue, Zhe Liu
{"title":"Effects of structurally varied fluorescent half-sandwich iridium(III) Schiff base complexes on A549 cell line","authors":"Xicheng Liu, Changjian Ji, Rui Tao, Wenya Zheng, Mengxian Liu, Shiqing Bi, Qinghua Chang, Xiang-Ai Yuan, Mingbo Yue, Zhe Liu","doi":"10.1016/j.jinorgbio.2024.112792","DOIUrl":"10.1016/j.jinorgbio.2024.112792","url":null,"abstract":"<div><div>Half-sandwich iridium(III) (Ir<sup>III</sup>) anticancer complexes, as promising alternatives to platinum-based drugs, especially for solving resistance to platinum drugs, have demonstrated excellent application prospect. The potency of these Ir<sup>III</sup> complexes as anticancer agents could be significantly enhanced through the strategic modification of their peripheral ligands. In this study, four structurally varied triphenylamine (TPA)-modified half-sandwich Ir<sup>III</sup> Schiff base complexes were designed and prepared. The incorporation of TPA unit has effectively endowed these complexes with suitable emission, which facilitates the evaluation of intracellular accumulation and cell morphology. These complexes demonstrated favorable in vitro anti-proliferative activity against A549 cell line (lung cancer cells, derived from alveolar basal epithelial cells), especially for pentamethylcyclopentadiene (Cp*)-based one (<strong>IrTS1</strong> and <strong>IrTS3</strong>), and that is almost 2.5-fold more than cisplatin under the same conditions. Meanwhile, <strong>IrTS1</strong> and <strong>IrTS3</strong> possessed excellent activity against A549/DDP (cisplatin-resistant) cell line and the similar cytotoxicity to cisplatin against BEAS-2B cell line (derived from the bronchial epithelium of normal human lungs), then following a mitochondria apoptotic channel.</div></div>","PeriodicalId":364,"journal":{"name":"Journal of Inorganic Biochemistry","volume":"263 ","pages":"Article 112792"},"PeriodicalIF":3.8,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yuxin Xuan , Yuxi Yan , Xiaonan Wei, Shuxiang Wang, Jinchao Zhang, Yonghe Tang, Shenghui Li
{"title":"Positively-charged, chalcone-hydroxypyrone hybrid ruthenium(II)-arene complexes functionalized with ethacrynic acid: Synthesis, characterizaion, and antitumor effect","authors":"Yuxin Xuan , Yuxi Yan , Xiaonan Wei, Shuxiang Wang, Jinchao Zhang, Yonghe Tang, Shenghui Li","doi":"10.1016/j.jinorgbio.2024.112778","DOIUrl":"10.1016/j.jinorgbio.2024.112778","url":null,"abstract":"<div><div>A new family of ethacrynic acid-functionalized, chalcone-hydroxypyrone hybrid ruthenium(II)-arene complexes (<strong>4a-4e</strong>) have been designed, synthesis and fully characterized by <sup>1</sup>H and <sup>13</sup>C NMR, ESI-MS, elemental analysis, and melting point tests. The molecular structure of <strong>3a</strong>, one of the precursor complexes, has been determined by single-crystal X-ray diffraction. The cytotoxicity of the obtained complexes toward human cancer cell lines such as HeLa, MGC803, A549, MDA-MB-231, and MCF-7 cells have been investigated by MTT assay. Whereas complexes <strong>4d</strong> and <strong>4e</strong> showed significantly higher cytotoxicity than cisplatin (the positive control group) and complexes <strong>3a-3e</strong>. Moreover, complexes <strong>4d</strong> and <strong>4e</strong> exhibited a certain selectivity (selectivity index: 7.33 and 7.57) toward MCF-7 cells over MCF-10a normal cells. Glutathione <em>S</em>-transferases (GSTs) activity assay indicate that complexes <strong>4d</strong> and <strong>4e</strong> exhibited higher GST inhibitory activity than ethacrynic acid (EA, the best characterized GST inhibitor), consistent with their higher cytotoxicity. Further mechanistic studies showed that <strong>4e</strong>-induced cell apoptosis may be aroused by the production of ROS, the loss of mitochondrial membrane potential and G2/M phase cell arrest in MCF-7 cells. In addition, the <em>in vivo</em> antitumor effect study on the xenograft mouse models of MCF-7 cells reveal that complex <strong>4e</strong> significantly inhibited tumor growth with a higher inhibition efficiency of 68.80 %, in comparison with the groups treated with cisplatin (59.25 %). These results highlight the strong possibility to develop positively-charged, chalcone-hydroxypyrone hybrid ruthenium(II)-arene complexes funcionalized with GST inhibitor as promising anticancer agents.</div></div>","PeriodicalId":364,"journal":{"name":"Journal of Inorganic Biochemistry","volume":"263 ","pages":"Article 112778"},"PeriodicalIF":3.8,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Expanding the scope of copper artificial metalloenzymes: A potential fluorinase?","authors":"Isabeau Lüddecke, Amanda G. Jarvis","doi":"10.1016/j.jinorgbio.2024.112777","DOIUrl":"10.1016/j.jinorgbio.2024.112777","url":null,"abstract":"<div><div>Biocatalysts for fluorination are rare, and thus of great interest for artificial enzyme design. Biohybrid catalysts including Cu-based DNAzymes and dinucleotide catalysts can catalyse enantioselective electrophilic fluorination of β-ketoesters. Here we report the investigation of Cu-based artificial metalloenzymes as catalysts for electrophilic fluorination reactions. A library of artificial copper proteins was prepared by bioconjugation of bidentate and tridentate nitrogen ligands to cysteine variants of the Sterol Carrier Protein 2 L (SCP-2 L) and subsequent addition of Cu(II) salts. The resulting copper proteins were screened for activity for the fluorination of β-ketoesters using Selectfluor. Under aqueous acidic conditions it was observed that the designed catalysts did not outcompete the uncatalysed background reaction. This work highlights that careful consideration of substrate reactivity and background reactions is needed when considering potential reactions for artificial metalloenzyme catalysis.</div></div>","PeriodicalId":364,"journal":{"name":"Journal of Inorganic Biochemistry","volume":"263 ","pages":"Article 112777"},"PeriodicalIF":3.8,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chiara Bacchella , Silvia De Caro , Stefania Nicolis , Enrico Monzani , Simone Dell'Acqua
{"title":"Hemin, copper and amyloid-β: A medley involved in Alzheimer's disease. An interaction that fine regulates the reactivity","authors":"Chiara Bacchella , Silvia De Caro , Stefania Nicolis , Enrico Monzani , Simone Dell'Acqua","doi":"10.1016/j.jinorgbio.2024.112775","DOIUrl":"10.1016/j.jinorgbio.2024.112775","url":null,"abstract":"<div><div>Metal ions have been shown to play a critical role in amyloid-β (Aβ) neurotoxicity and plaque formation which are key hallmarks of Alzheimer's disease. Amyloid-β peptides can bind both copper and hemin and this interaction modulates the redox chemistry of these metals. The characterization of the binding of hemin through UV–Vis spectroscopic titration with Aβ(4-16) shows a significantly higher affinity than that with Aβ(1-16). Also, the characterization of the hemin-catalyzed oxidation through different assays (peroxidase-like activity, ascorbate oxidation, HPLC-MS analysis of peptide oxidation) displays a greater reactivity in the presence of Aβ(4-16) when compared to that of Aβ(1-16). Since the Aβ(4-16) peptide sequence contains the typical amino-terminal copper and nickel binding motif (ATCUN), this leads to investigate the potential formation of ternary hemin/copper/Aβ(4-16) adducts. The evaluation of K<sub>1</sub> and K<sub>2</sub> (constants that regulate the formation of five-coordinated high-spin complex and of six-coordinated low-spin complex, respectively) for mixed systems indicates that the presence of copper stabilizes the 1:1 hemin-Aβ(4-16) species, partially hindering the formation of the low-spin complex. On the other hand, the formation of the ternary hemin/copper/Aβ(4-16) complex gives rise to a less efficient catalyst, resulting in a reduction of the overall oxidative reactivity. These results suggest that the reactivity of metal ions is finely modulated by the formation of complexes with amyloid peptides and this property is also regulated differently by the various in vivo relevant isoforms.</div></div>","PeriodicalId":364,"journal":{"name":"Journal of Inorganic Biochemistry","volume":"263 ","pages":"Article 112775"},"PeriodicalIF":3.8,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142699574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sudha Yadav, Robert S. Lyons, Zoe Readi-Brown, Maxime A. Siegler, David P. Goldberg
{"title":"Influence of the second coordination sphere on O2 activation by a nonheme iron(II) thiolate complex","authors":"Sudha Yadav, Robert S. Lyons, Zoe Readi-Brown, Maxime A. Siegler, David P. Goldberg","doi":"10.1016/j.jinorgbio.2024.112776","DOIUrl":"10.1016/j.jinorgbio.2024.112776","url":null,"abstract":"<div><div>The synthesis and characterization of a new ligand, 1-(bis(pyridin-2-ylmethyl) amino)-2-methylpropane-2-thiolate (BPA<sup>Me2</sup>S<sup>−</sup>) and its nonheme iron complex, Fe<sup>II</sup>(BPA<sup>Me2</sup>S)Br (<strong>1</strong>), is reported. Reaction of <strong>1</strong> with O<sub>2</sub> at −20 °C generates a high-spin iron(III)-hydroxide complex, [Fe<sup>III</sup>(OH)(BPA<sup>Me2</sup>S)(Br)] (<strong>2</strong>), that was characterized by UV–vis, <sup>57</sup>Fe Mössbauer, and electron paramagnetic resonance (EPR) spectroscopies, and electrospray ionization mass spectrometry (ESI-MS). Density functional theory (DFT) calculations were employed to support the spectroscopic assignments. In a previous report (<em>J. Am. Chem. Soc.</em> <strong>2024</strong>, <em>146</em>, 7915–7921), the related iron(II) complex, Fe<sup>II</sup>(BNPA<sup>Me2</sup>S)Br (BNPA<sup>Me2</sup>S<sup>−</sup> = (bis((6-(neopentylamino)pyridinyl) methyl)amino)-2-methylpropane-2-thiolate) was reported and shown to react with O<sub>2</sub> at low temperature to give a rare iron(III)-superoxide intermediate, which then converts to an S‑oxygenated sulfinate as seen for the nonheme iron thiol dioxygenases. This complex includes two hydrogen bonding neopentylamino groups in the second coordination sphere. Complex <strong>1</strong> does not include these H-bonding groups, and its reactivity with O<sub>2</sub> does not yield a stabilized Fe/O<sub>2</sub> intermediate or S‑oxygenated products, although the data suggest an inner-sphere mechanism and formation of an iron‑oxygen species that is capable of abstracting hydrogen atoms from solvent or weak C<img>H bond substrates. This study indicates that the H-bond donors are critical for stabilizing the Fe<sup>III</sup>(O<sub>2</sub><sup>-•</sup>) intermediate with the BNPA<sup>Me2</sup>S<sup>−</sup> ligand, which in turn leads to S‑oxygenation, as opposed to H-atom abstraction, following O<sub>2</sub> activation by the nonheme iron center<sub>.</sub></div></div>","PeriodicalId":364,"journal":{"name":"Journal of Inorganic Biochemistry","volume":"264 ","pages":"Article 112776"},"PeriodicalIF":3.8,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142790828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shelby T. Harris, Jordan Gardner, Alexia Davis, Julia Steed, Steven Christiansen, Stewart Ryberg, Weston Ludlow, Mitchell Pendleton, Blake Grimshaw, Richard K. Watt
{"title":"Physiological iron chelators pyrophosphate and citrate have different effects on the proportions of monoferric transferrin metalloforms","authors":"Shelby T. Harris, Jordan Gardner, Alexia Davis, Julia Steed, Steven Christiansen, Stewart Ryberg, Weston Ludlow, Mitchell Pendleton, Blake Grimshaw, Richard K. Watt","doi":"10.1016/j.jinorgbio.2024.112773","DOIUrl":"10.1016/j.jinorgbio.2024.112773","url":null,"abstract":"<div><div>Human serum transferrin can bind up to two iron atoms, one in each of its two domains which are known as the N-lobe and the C-lobe. Ferric pyrophosphate and ferric citrate have been shown to direct loading into the C-lobe and N-lobe, respectively. We report that the iron supplement ferric pyrophosphate citrate directs iron to the C-lobe. We also show that pyrophosphate directs iron to the C-lobe as a free anion even at the concentrations found in human plasma. This indicates that pyrophosphate may play a physiological role in transferrin iron loading and body iron homeostasis. We also present a validation of an existing micellar capillary electrophoresis technique for separating the four transferrin metalloforms, which has potential to be adapted for use in a clinical setting.</div></div>","PeriodicalId":364,"journal":{"name":"Journal of Inorganic Biochemistry","volume":"263 ","pages":"Article 112773"},"PeriodicalIF":3.8,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142699528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rosa Bellavita , Bruno Casciaro , Valeria Nocerino , Sara Palladino , Maria Rosa Loffredo , Principia Dardano , Luca De Stefano , Lucia Falcigno , Gabriella D'Auria , Stefania Galdiero , Annarita Falanga
{"title":"Myxinidin-analogs able to sequester Fe(III): Metal-based gun to combat Pseudomonas aeruginosa biofilm","authors":"Rosa Bellavita , Bruno Casciaro , Valeria Nocerino , Sara Palladino , Maria Rosa Loffredo , Principia Dardano , Luca De Stefano , Lucia Falcigno , Gabriella D'Auria , Stefania Galdiero , Annarita Falanga","doi":"10.1016/j.jinorgbio.2024.112774","DOIUrl":"10.1016/j.jinorgbio.2024.112774","url":null,"abstract":"<div><div>Bacteria have developed a tendency to form biofilms, where bacteria live in organized structures embedded in a self-produced matrix of DNA, proteins, and polysaccharides. Additionally, bacteria need iron(III) as an essential nutrient for bacterial growth and secrete siderophore groups that sequester it from the environment. To design a molecule able both to inhibit the bacteria and to sequester iron, we developed two hydroxamate-based peptides derived from an analog (WMR-4), previously developed in our lab, of the antimicrobial peptide myxinidin.</div><div>In detail, we proposed a combination of WMR-4 with the hydroxamic acid resulting in the peptides WMR-7 and WMR-16 which differ for the length of the linker between the antimicrobial moiety and the siderophore. Both peptides were characterized through a set of different biophysical experiments to investigate their ability to sequester Fe<sup>3+</sup>. The peptide‑iron(III) complexes were studied through the UV–visible spectroscopy in organic solvent to eliminate water competition, and in acidic water to avoid iron precipitation. The complexes were also characterized by performing electrochemistry, circular dichroism and NMR spectroscopy experiments. In addition, we demonstrated the ability of peptide‑iron(III) complexes to inhibit the biofilm of <em>Pseudomonas aeruginosa</em> and to have an impact on the cell motility. This metal-based approach consisting in a hydroxamic acid conjugation represents a promising strategy to enhance the antibiofilm activity of antimicrobial peptides against one of most dangerous bacteria such as <em>Pseudomonas aeruginosa.</em></div></div>","PeriodicalId":364,"journal":{"name":"Journal of Inorganic Biochemistry","volume":"263 ","pages":"Article 112774"},"PeriodicalIF":3.8,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142674752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yun Song , Jing Wang , Yajun Sun , Shijia Dong , Guangying Yu , Wenjing Lin , Yinhua Xiong , Yanhui Tan , Yanshi Xiong , Guijuan Jiang , Jintao Wang , Xiangwen Liao , Lianghong Liu
{"title":"Targeting bacterial efflux pump effectively enhances the efficacy of Ru-based antibacterial agents against Gram-negative pathogen","authors":"Yun Song , Jing Wang , Yajun Sun , Shijia Dong , Guangying Yu , Wenjing Lin , Yinhua Xiong , Yanhui Tan , Yanshi Xiong , Guijuan Jiang , Jintao Wang , Xiangwen Liao , Lianghong Liu","doi":"10.1016/j.jinorgbio.2024.112772","DOIUrl":"10.1016/j.jinorgbio.2024.112772","url":null,"abstract":"<div><div>The rise of antibiotic resistance has posed a great threat to human's life, thus develop novel antibacterial agents is urgently needed. It worthies to noted that Ru-based antibacterial agents often showed robust potency against Gram-positive pathogens, disrupted bacterial membrane and avoided bacterial resistance, making they promising antibiotic candidates. However, they are generally less active when applied to negative pathogens. To address this problem, a Ru-based metalloantibiotic (<strong>RuN</strong>) modified with a nitrothiophene moiety, which can target bacterial efflux pump, was designed and evaluated in this work. A series of assays demonstrated that <strong>RuN</strong> not only fully retained the advantages of Ru-based agents, such as destroyed bacterial membrane and induced reactive oxygen species production, but also can targeted bacterial efflux pumps. Of course, these properties make it effective in killing both Gram-positive and negative pathogens, its MIC values against <em>Staphylococcus aureus</em> and <em>Escherichia coli</em> lies at 3.125 and 6.25 μg/mL, respectively. Importantly, <strong>RuN</strong> also showed low toxicity and has robust anti-infective potency in two animal infection models. Together, our results paved an alternative way to enhance the anti-infective efficacy of Ru-based agents against resistant negative bacteria.</div></div>","PeriodicalId":364,"journal":{"name":"Journal of Inorganic Biochemistry","volume":"263 ","pages":"Article 112772"},"PeriodicalIF":3.8,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142646549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jinfeng Zheng , Xiufeng Wang , Huan Du , Ruyan Zhang , Xiaobing Huo , Ting Zhou , Guodong Zhang , Fang Wang , Qianxiong Zhou , Zhiqing Zhang
{"title":"Multifunctional Ru(III)/Fe3O4/DNA nanoplatform for photothermal-enhanced photodynamic and chemodynamic cancer therapy","authors":"Jinfeng Zheng , Xiufeng Wang , Huan Du , Ruyan Zhang , Xiaobing Huo , Ting Zhou , Guodong Zhang , Fang Wang , Qianxiong Zhou , Zhiqing Zhang","doi":"10.1016/j.jinorgbio.2024.112771","DOIUrl":"10.1016/j.jinorgbio.2024.112771","url":null,"abstract":"<div><div>Among the many cancer treatment methods, there have been many reports on the use of nanoplatforms with single treatment methods such as photothermal, photodynamic or chemodynamic for cancer treatment. In this study, Ru(III) with photodynamic effect and Fe<sub>3</sub>O<sub>4</sub> nanoparticles with photothermal and chemodynamic effects are connected through long DNA chains with efficient active targeting rolling circle amplification to construct Ru(III)/Fe<sub>3</sub>O<sub>4</sub>/DNA nano-platform realizes the combination of photothermal, photodynamic and chemodynamic treatment, which significantly improves the therapeutic effect of the nano-platform. Its multiple active targeting capabilities reduce the damage to normal cells. Ru(III) has excellent photodynamic effect and can catalyze the respiration product NADH (Nicotinamide adenine dinucleotide)to produce highly oxidizing H<sub>2</sub>O<sub>2</sub>. Fe<sub>3</sub>O<sub>4</sub> NPs has weak absorption at 808 nm indicates that it can perform mild photothermal treatment, and the Fe<sup>2+</sup> in it can react with H<sub>2</sub>O<sub>2</sub> to produce ·OH and participate in chemodynamic treatment. Each repeating unit on the rolling circle amplified DNA long chain is connected to the AS1411 aptamer that can actively target cancer cells. Unlike the passive targeting of other nanomedicines, active and efficient targeting is achieved, and a small amount of drugs can achieve high efficacy. The therapeutic effect also reduces the damage to normal cells. The comprehensive killing effect of Ru(III)/Fe<sub>3</sub>O<sub>4</sub>/DNA can reach 85.1 %. Its high targeting of cancer cells can also be used for imaging detection of cancer cells. This new nanoplatform provides an idea for the synergy of multiple cancer treatments.</div></div>","PeriodicalId":364,"journal":{"name":"Journal of Inorganic Biochemistry","volume":"262 ","pages":"Article 112771"},"PeriodicalIF":3.8,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142586538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Exploring divalent metal ion coordination. Unraveling binding modes in Staphylococcus aureus MntH fragments","authors":"Valentyn Dzyhovskyi , Maurizio Remelli , Kamila Stokowa-Sołtys","doi":"10.1016/j.jinorgbio.2024.112769","DOIUrl":"10.1016/j.jinorgbio.2024.112769","url":null,"abstract":"<div><div>Metal ion coordination is crucial in bacterial metabolism, while divalent metal ions serve as essential cofactors for various enzymes involved in cellular processes. Therefore, bacteria have developed sophisticated regulatory mechanisms to maintain metal homeostasis. These involve protein interactions for metal ion uptake, efflux, intracellular transport, and storage. <em>Staphylococcus aureus</em>, a member of the commensal flora, colonizes the anterior nares and skin harmlessly but can cause severe illness. MntH transporter is responsible for acquiring divalent metal ions necessary for metabolic functions and virulence. It is a 450-amino-acid protein analogous to Nramp1 (Natural Resistance-Associated Macrophage Protein 1) in mammals. Herein, the coordination modes of copper(II), iron(II), and zinc(II) ions with select fragments of the MntH were established employing potentiometry, mass spectrometry, and spectroscopic methods. Four model peptides, MNNKRHSTNE–NH<sub>2</sub>, Ac-KFDHRSS–NH<sub>2</sub>, Ac-IMPHNLYLHSSI–NH<sub>2</sub>, and Ac-YSRHNNEE–NH<sub>2</sub>, were chosen for their metal-binding capabilities and examined to determine their coordination properties and preferences. Our findings suggest that under physiological pH conditions, the N-terminal fragment of MntH demonstrates the highest thermodynamic stability with copper(II) and iron(II) ions. Furthermore, a comparison with other peptides from the <em>S. aureus</em> FeoB transporter indicates different binding affinities.</div></div>","PeriodicalId":364,"journal":{"name":"Journal of Inorganic Biochemistry","volume":"263 ","pages":"Article 112769"},"PeriodicalIF":3.8,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142643628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}