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Melenbacher A, Stillman MJ. Metallothionein-3: 63 Cu(I) binds to human 68 Zn 7 -βα MT3 with no preference for Cu 4 -β cluster formation. FEBS J 2023; 290:4316-4341. [PMID: 37165729 DOI: 10.1111/febs.16812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/25/2023] [Accepted: 05/09/2023] [Indexed: 05/12/2023]
Abstract
Human metallothioneins (MTs) are involved in binding the essential elements, Cu(I) and Zn(II), and the toxic element, Cd(II), in metal-thiolate clusters using 20 reduced cysteines. The brain-specific MT3 binds a mixture of Cu(I) and Zn(II) in vivo. Its metallation properties are critically important because of potential connections between Cu, Zn and neurodegenerative diseases. We report that the use of isotopically pure 63 Cu(I) and 68 Zn(II) greatly enhances the element resolution in the ESI-mass spectral data revealing species with differing Cu:Zn ratios but the same total number of metals. Room temperature phosphorescence and circular dichroism spectral data measured in parallel with ESI-mass spectral data identified the presence of specific Cu(I)-thiolate clusters in the presence of Zn(II). A series of Cu(I)-thiolate clusters form following Cu(I) addition to apo MT3: the two main clusters that form are a Cu6 cluster in the β domain followed by a Cu4 cluster in the α domain. 63 Cu(I) addition to 68 Zn7 -MT3 results in multiple species, including clustered Cu5 Zn5 -MT3 and Cu9 Zn3 -MT3. We assign the domain location of the metals for Cu5 Zn5 -MT3 as a Cu5 Zn1 -β cluster and a Zn4 -α cluster and for Cu9 Zn3 -MT3 as a Cu6 -β cluster and a Cu3 Zn3 -α cluster. While many reports of the average MT3 metal content exist, determining the exact Cu,Zn stoichiometry has proven very difficult even with native ESI-MS. The work in this paper solves the ambiguity introduced by the overlap of the naturally abundant Cu(I) and Zn(II) isotopes. Contrary to other reports, there is no indication of a major fraction of Cu4 -β-Znn -α-MT3 forming.
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Affiliation(s)
- Adyn Melenbacher
- Department of Chemistry, The University of Western Ontario, London, Canada
| | - Martin J Stillman
- Department of Chemistry, The University of Western Ontario, London, Canada
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2
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Yuan AT, Liu L, Chang LY, Stillman MJ. Xenobiotic Bi 3+ Coordination by Cysteine-Rich Metallothionein-3 Reveals a Cooperatively Formed Thiolate-Sharing Bi 2S 5 Cluster. Inorg Chem 2023; 62:13011-13020. [PMID: 37535952 DOI: 10.1021/acs.inorgchem.3c01796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/05/2023]
Abstract
The field of designing artificial metalloproteins has yet to effectively tackle the incorporation of multimetal clusters, which is a key component of natural metalloproteins, such as metallothioneins (MTs) and calmodulin. MT is a physiological, essential, cysteine-rich metalloprotein that binds to a variety of metals but is only known to form metal-thiolate clusters with Cd2+, Zn2+, and Cu+. Bismuth is a xenobiotic metal and a component of metallodrugs used to treat gastric ulcers and cancer, as well as an emerging metal used in industrial practices. Electrospray ionization mass spectrometry, UV-visible spectroscopy, and extended X-ray absorption fine structure spectroscopy were used to probe the Bi3+ binding site structures in apo-MT3 (brain-located MT) at pH 7.4 and 2 and provide the complete set of binding affinities. We discovered the highly cooperative formation of a novel Bi3+ species, Bi2MT3, under physiological conditions, where each Bi3+ ion is coordinated by three cysteinyl thiolates, with one of the thiolates bridging between the two Bi3+ ions. This cluster structure was associated with a strong visible region absorption band, which was disrupted by the addition of Zn2+ and reversibly disrupted by acidification and increased temperature. This is the first reported presence of bridging cysteines for a xenobiotic metal in MT3 and the Bi2MT structure is the first Bi cluster found in a metalloprotein.
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Affiliation(s)
- Amelia T Yuan
- Department of Chemistry, University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7 Canada
| | - Lijia Liu
- Department of Chemistry, University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7 Canada
| | - Lo-Yueh Chang
- National Synchrotron Radiation Research Center (NSRRC), 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 300092, Taiwan, ROC
| | - Martin J Stillman
- Department of Chemistry, University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7 Canada
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3
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Schmorl S, Börner M, Kersting B. Stable thiolate adducts of Rh 2(OAc) 4 - assembly of hexametallic Ni 4Rh 2 complexes. Dalton Trans 2021; 51:59-62. [PMID: 34889331 DOI: 10.1039/d1dt03509f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Thiolate adducts of dirhodium(II) tetraacetate have proven difficult to prepare. We isolated a stable, paramagnetic Ni4Rh2 adduct containing Ni-based metallothiolates bound in axial positions of the Rh24+ core. The adduct formation is accompanied by a change of the magnetic exchange interaction in the dinuclear Ni2 subunits.
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Affiliation(s)
- Sara Schmorl
- Institut für Anorganische Chemie, Universität Leipzig, Johannisallee 29, 04103 Leipzig, Germany.
| | - Martin Börner
- Institut für Anorganische Chemie, Universität Leipzig, Johannisallee 29, 04103 Leipzig, Germany.
| | - Berthold Kersting
- Institut für Anorganische Chemie, Universität Leipzig, Johannisallee 29, 04103 Leipzig, Germany.
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Wong DL, Yuan AT, Korkola NC, Stillman MJ. Interplay between Carbonic Anhydrases and Metallothioneins: Structural Control of Metalation. Int J Mol Sci 2020; 21:E5697. [PMID: 32784815 PMCID: PMC7460868 DOI: 10.3390/ijms21165697] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 07/31/2020] [Accepted: 08/05/2020] [Indexed: 12/13/2022] Open
Abstract
Carbonic anhydrases (CAs) and metallothioneins (MTs) are both families of zinc metalloproteins central to life, however, they coordinate and interact with their Zn2+ ion cofactors in completely different ways. CAs and MTs are highly sensitive to the cellular environment and play key roles in maintaining cellular homeostasis. In addition, CAs and MTs have multiple isoforms with differentiated regulation. This review discusses current literature regarding these two families of metalloproteins in carcinogenesis, with a dialogue on the association of these two ubiquitous proteins in vitro in the context of metalation. Metalation of CA by Zn-MT and Cd-MT is described. Evidence for protein-protein interactions is introduced from changes in metalation profiles of MT from electrospray ionization mass spectrometry and the metalation rate from stopped-flow kinetics. The implications on cellular control of pH and metal donation is also discussed in the context of diseased states.
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Affiliation(s)
| | | | | | - Martin J. Stillman
- Department of Chemistry, The University of Western Ontario, 1151 Richmond St., London, ON N6A5B7, Canada; (D.L.W.); (A.T.Y.); (N.C.K.)
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Merlos Rodrigo MA, Jimenez Jimemez AM, Haddad Y, Bodoor K, Adam P, Krizkova S, Heger Z, Adam V. Metallothionein isoforms as double agents - Their roles in carcinogenesis, cancer progression and chemoresistance. Drug Resist Updat 2020; 52:100691. [PMID: 32615524 DOI: 10.1016/j.drup.2020.100691] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 02/25/2020] [Accepted: 03/01/2020] [Indexed: 02/06/2023]
Abstract
Metallothioneins (MTs) are small cysteine-rich intracellular proteins with four major isoforms identified in mammals, designated MT-1 through MT-4. The best known biological functions of MTs are their ability to bind and sequester metal ions as well as their active role in redox homeostasis. Despite these protective roles, numerous studies have demonstrated that changes in MT expression could be associated with the process of carcinogenesis and participation in cell differentiation, proliferation, migration, and angiogenesis. Hence, MTs have the role of double agents, i.e., working with and against cancer. In view of their rich biochemical properties, it is not surprising that MTs participate in the emergence of chemoresistance in tumor cells. Many studies have demonstrated that MT overexpression is involved in the acquisition of resistance to anticancer drugs including cisplatin, anthracyclines, tyrosine kinase inhibitors and mitomycin. The evidence is gradually increasing for a cellular switch in MT functions, showing that they indeed have two faces: protector and saboteur. Initially, MTs display anti-oncogenic and protective roles; however, once the oncogenic process was launched, MTs are utilized by cancer cells for progression, survival, and contribution to chemoresistance. The duality of MTs can serve as a potential prognostic/diagnostic biomarker and can therefore pave the way towards the development of new cancer treatment strategies. Herein, we review and discuss MTs as tumor disease markers and describe their role in chemoresistance to distinct anticancer drugs.
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Affiliation(s)
- Miguel Angel Merlos Rodrigo
- Central European Institute of Technology, Brno University of Technology, Purkynova 123, CZ-612 00 Brno, Czech Republic; Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic.
| | - Ana Maria Jimenez Jimemez
- Central European Institute of Technology, Brno University of Technology, Purkynova 123, CZ-612 00 Brno, Czech Republic; Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic
| | - Yazan Haddad
- Central European Institute of Technology, Brno University of Technology, Purkynova 123, CZ-612 00 Brno, Czech Republic; Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic
| | - Khaldon Bodoor
- Department of Applied Biology, Jordan University of Science and Technology, 3030, Irbid, Jordan
| | - Pavlina Adam
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic
| | - Sona Krizkova
- Central European Institute of Technology, Brno University of Technology, Purkynova 123, CZ-612 00 Brno, Czech Republic; Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic
| | - Zbynek Heger
- Central European Institute of Technology, Brno University of Technology, Purkynova 123, CZ-612 00 Brno, Czech Republic; Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic
| | - Vojtech Adam
- Central European Institute of Technology, Brno University of Technology, Purkynova 123, CZ-612 00 Brno, Czech Republic; Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic.
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Coordination-Induced Self-Assembly of a Heteroleptic Paddlewheel-Type Dirhodium Complex. CRYSTALS 2020. [DOI: 10.3390/cryst10020085] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A novel heteroleptic paddlewheel-type dirhodium (Rh2) complex [Rh2(O2CCH3)3(PABC)] (1; PABC = para-aminobenzenecarboxylate), which has an amino group as a potential donor site for coordination with the metal ion, was synthesized and characterized by 1H NMR, ESI-TOF-MS, infrared spectra, and elemental analysis. The slow evaporation of N,N-dimethylformamide (DMF)-dissolved 1 produces the purple-colored crystalline polymeric species [Rh2(O2CCH3)3 (PABC)(DMF)]n (1P). Single-crystal and powder X-ray diffraction analyses, as well as thermo-gravimetric analysis, clarified that 1P formed a one-dimensional polymeric structure, in which the two axial sites of the Rh2 ion in 1P are coordinated by a DMF molecule and an amino group of the PABC ligand of the neighboring molecule 1, by coordination-induced self-assembly (polymerization) with an Rh-amino bond. The reversible structural change (self-assembly and disassembly transformations) between the discrete species [Rh2(O2CCH3)3(PABC)(DMF)2] (1D; green solution) and the polymeric species 1P (purple solid) was accompanied by a color change, which easily occurred by the dissolution and evaporation procedures with DMF.
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Enriquez Garcia A, Jalilehvand F, Niksirat P. Reactions of Rh 2(CH 3COO) 4 with thiols and thiolates: a structural study. JOURNAL OF SYNCHROTRON RADIATION 2019; 26:450-461. [PMID: 30855255 PMCID: PMC6412178 DOI: 10.1107/s160057751900033x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 01/07/2019] [Indexed: 06/09/2023]
Abstract
The structural differences between the aerobic reaction products of Rh2(AcO)4 (1; AcO- = CH3COO-) with thiols and thiolates in non-aqueous media are probed by X-ray absorption spectroscopy. For this study, ethanethiol, dihydrolipoic acid (DHLA; a dithiol) and their sodium thiolate salts were used. Coordination of simple thiols to the axial positions of Rh2(AcO)4 with Rh-SH bonds of 2.5-2.6 Å keeps the RhII-RhII bond intact (2.41 ± 0.02 Å) but leads to a colour change from emerald green to burgundy. Time-dependent density functional theory (TD-DFT) calculations were performed to explain the observed shifts in the electronic (UV-vis) absorption spectra. The corresponding sodium thiolates, however, break up the Rh2(AcO)4 framework in the presence of O2 to form an oligomeric chain of triply S-bridged Rh(III) ions, each with six Rh-S (2.36 ± 0.02 Å) bonds. The RhIII...RhIII distance, 3.18 ± 0.02 Å, in the chain is similar to that previously found for the aerobic reaction product from aqueous solutions of Rh2(AcO)4 and glutathione (H3A), {Na2[Rh2III(HA)4]·7H2O}n, in which each Rh(III) ion is surrounded by about four Rh-S (2.33 ± 0.02 Å) and about two Rh-O (2.08 ± 0.02 Å). The reaction products obtained in this study can be used to predict how dirhodium(II) tetracarboxylates would react with cysteine-rich proteins and peptides, such as metallothioneins.
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Affiliation(s)
- Alejandra Enriquez Garcia
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4
| | - Farideh Jalilehvand
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4
| | - Pantea Niksirat
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4
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8
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Wong DL, Stillman MJ. Metallothionein: An Aggressive Scavenger-The Metabolism of Rhodium(II) Tetraacetate (Rh 2(CH 3CO 2) 4). ACS OMEGA 2018; 3:16314-16327. [PMID: 31458267 PMCID: PMC6643557 DOI: 10.1021/acsomega.8b02161] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 11/13/2018] [Indexed: 06/10/2023]
Abstract
Anthropogenic sources of xenobiotic metals with no physiological benefit are increasingly prevalent in the environment. The platinum group metals (Pd, Pt, Rh, Ru, Os, and Ir) are found in marine and plant species near urban sources, and are known to bioaccumulate, introducing these metals into the human food chain. Many of these metals are also being used in innovative cancer therapy, which leads to a direct source of exposure for humans. This paper aims to further our understanding of nontraditional metal metabolism via metallothionein, a protein involved in physiologically important metal homeostasis. The aggressive reaction of metallothionein and dirhodium(II) tetraacetate, a common synthetic catalyst known for its cytotoxicity, was studied in detail in vitro. Optical spectroscopic and equilibrium and time-dependent mass spectral data were used to define binding constants for this robust reaction, and molecular dynamics calculations were conducted to explain the observed results.
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Affiliation(s)
- Daisy L. Wong
- Department of Chemistry, The
University of Western Ontario, 1151 Richmond Street, N6A 5B7 London, Ontario, Canada
| | - Martin J. Stillman
- Department of Chemistry, The
University of Western Ontario, 1151 Richmond Street, N6A 5B7 London, Ontario, Canada
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9
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Scheller JS, Irvine GW, Stillman MJ. Unravelling the mechanistic details of metal binding to mammalian metallothioneins from stoichiometric, kinetic, and binding affinity data. Dalton Trans 2018; 47:3613-3637. [PMID: 29431781 DOI: 10.1039/c7dt03319b] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Metallothioneins (MTs) are small, cysteine-rich proteins, found throughout Nature. Their ability to bind a number of different metals with a range of stoichiometric ratios means that this protein family is critically important for essential metal (Zn2+ and Cu+) homeostasis, metal storage, metal donation to nascent metalloenzymes as well as heavy metal detoxification. With its 20 cysteines, metallothionein is also considered to protect cells against oxidative stress. MT has been studied by a large number of researchers over the last 6 decades using a variety of spectroscopic techniques. The lack of distinguishing chromophores for the multitude of binding sites has made the evaluation of stoichiometric properties for different metals challenging. Initially, only 113Cd-NMR spectroscopy could provide strong evidence for the proposed cluster formation of Cd-MT. The extraordinary development of electrospray ionization mass spectrometry (ESI-MS), where all coexisting species in solution are observed, revolutionized MT research. Prior to the use of ESI-MS data, a range of "magic numbers" representing metal-to-MT molar ratios were reported from optical spectroscopic studies. The availability of ESI mass spectral data led to (i) the confirmation of cluster formation, (ii) a conceptual understanding of the cooperativity involved in multiple metal binding events, (iii) the presence of domain specificity between regions of the protein and (iv) mechanistic details involving both binding affinities and rate constants. The kinetic experiments identified the presence of multiple individual binding sites, each with a unique rate constant and an analogous binding affinity. The almost linear trend in rate constants as a function of bound As3+ provided a unique insight that became a critical step in the complete understanding of the mechanistic details of the metalation of MT. To fully define the biological function of this sulfur-rich protein it is necessary to determine kinetic rate constants and binding affinities for the essential metals. Recently, Zn2+ competition experiments between both of the isolated fragments (α and β) and the full-length protein (βα-MT 1a) as well as Zn2+ competition between βα-MT 1a and carbonic anhydrase were reported. From these data, the trend in binding affinities and the values of the Kf of the 7 bimolecular reactions involved in metalation were determined. From the analysis of ESI-MS data for Cu+ binding to βα-MT 1a at different pH-values, a trend in the 20 binding affinities for the complete metalation mechanism was reported. This review details a personal view of the historical development of the determination of stoichiometry for metal binding, the structure of the binding sites, the rates of the metalation reactions and the underlying binding affinities for each metalation step. We have attempted to summarize the experimental developments that led to the publication in May 2017 of the experimental determination of the 20 binding constants for the 20 sequential bimolecular reactions for Cu+ binding to the 20 Cys of apoMT as a function of pH that show the appearance and disappearance of clusters. We report both published data and in a series of tables an assembly of stoichiometries, and equilibrium constants for Zn2+ and Cu+ for many different metallothioneins.
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Affiliation(s)
- Judith S Scheller
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada.
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Isolated domains of recombinant human apo-metallothionein 1A are folded at neutral pH: a denaturant and heat-induced unfolding study using ESI-MS. Biosci Rep 2018; 38:BSR20180592. [PMID: 29858425 PMCID: PMC6050192 DOI: 10.1042/bsr20180592] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 05/31/2018] [Accepted: 06/01/2018] [Indexed: 12/25/2022] Open
Abstract
Metallothioneins (MTs) are characterized by their high metal loading capacity, small molecular weight, and abundant cysteine residues. It has long been thought that metal-free, or apo-MT peptides were unstructured and only adopted as a distinct conformation upon forming the metal clusters, described as metal-induced folding. More recent studies have suggested that the presence of a globular, yet loosely defined structure actually exists that can be disrupted or unfolded. Residue modification and ion-mobility ESI (IM-ESI)-MS have been used to examine this unusual unfolding process. The structure of apo-MT plays a critical role as the starting point in the flexible metalation pathways that can accommodate numerous soft metals. ESI-MS measurements of the product species formed following the cysteine alkylation of the isolated domain fragments of recombinant human apo-MT 1A with n-ethylmaleimide (NEM) were used in the present study to monitor the denaturant- and heat-induced unfolding at physiological pH. The results indicate that these apo-MT fragments adopt distinct structures at neutral pH that react co-operatively with NEM when folded and non-cooperatively when heated or exposed to high concentrations of the denaturant guanidinium chloride (GdmCl). From these studies, we can conclude that at neutral pH, the domain fragments are folded into globular structures where some of the free cysteine residues are buried within the core and are stabilized by hydrogen bonds. Metalation therefore, must take place from the folded conformation.
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Valentín-Pérez Á, Perles J, Herrero S, Jiménez-Aparicio R. Coordination capacity of cytosine, adenine and derivatives towards open-paddlewheel diruthenium compounds. J Inorg Biochem 2018; 187:109-115. [PMID: 30077945 DOI: 10.1016/j.jinorgbio.2018.06.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 06/01/2018] [Accepted: 06/14/2018] [Indexed: 12/11/2022]
Abstract
[Ru2Cl2(DPhF)3] (DPhF = diphenylformamidinate) links preferentially to the junctions of RNA (ribonucleic acid) structures, although the bonding mode is not known. In order to clarify this question the reactions between [Ru2Cl2(DPhF)3] and cytosine (Hcyto), cytidine (Hcyti), cytidine 2',3'-cyclic monophosphate sodium salt (NacCMP), adenine (Hade), adenosine (Haden) and adenosine 3',5'-cyclic monophosphate (HcAMP) have been carried out. In the resultant complexes, cyto (cytosinate), cyti (cytidinate), cCMP (cytidine 2',3'-cyclic monophosphate monoanion), ade (adeninate), aden (adenosinate) and cAMP (deprotonated adenosine 3',5'-cyclic monophosphate) are bonded to the diruthenium unit as N,N'-bridging ligands, as confirmed by the solution of the crystal structures of [RuCl(DPhF)3(cyto)] and [RuCl(DPhF)3(ade)] by X-ray diffraction. The axial positions of the diruthenium species are still available for additional interactions with other residues that could explain its preference towards RNA junctions.
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Affiliation(s)
- Ángela Valentín-Pérez
- Departamento de Química Inorgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Ciudad Universitaria, E-28040 Madrid, Spain
| | - Josefina Perles
- Laboratorio de Difracción de Rayos X de Monocristal, Servicio Interdepartamental de Investigación, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Santiago Herrero
- Departamento de Química Inorgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Ciudad Universitaria, E-28040 Madrid, Spain.
| | - Reyes Jiménez-Aparicio
- Departamento de Química Inorgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Ciudad Universitaria, E-28040 Madrid, Spain.
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Wong DL, Zhang A, Faponle AS, de Visser SP, Stillman MJ. Glutathione binding to dirhodium tetraacetate: a spectroscopic, mass spectral and computational study of an anti-tumour compound. Metallomics 2018; 9:501-516. [PMID: 28474044 DOI: 10.1039/c7mt00040e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Glutathione (γ-l-glutamyl-l-cysteinyl-glycine) is a ubiquitous tripeptide found in all plants and animals. Glutathione has key roles as a metallochaperone and as a cellular thiol involved in metabolism. Little is known about how glutathione interacts with organometallic compounds in vivo. Here, we report the reactions of glutathione in vitro with dirhodium(ii) tetraacetate (tetrakis(μ-acetato)dirhodium(ii), Rh2(OAc)4), a compound with anti-tumour properties. Electrospray ionization mass spectrometry, UV-Visible absorption and circular dichroism spectroscopic methods were used to determine the stoichiometries and optical properties of the final conjugate. Computational analyses were used to predict the binding modes of glutathione to the Rh2(OAc)4, and report on the orbital assignments for the resulting products. We explored the competition by GSH for methionine-bound axial sites on Rh2(OAc)4 to investigate the use of weak thioether to protect its cellular-based anti-cancer activity. Our study highlights the important role that axial ligation would play in deactivating or significantly decreasing the efficacy of this bimetallic anti-tumor drug. The computational data explain the stability of the mono-adduct and the appearance of new absorption bands in the UV region including retention of the Rh-Rh single bond. Additionally, these data show that glutathione can effectively disable the potency of these metallo-drugs through orbital overlap of the entire Rh-Rh core as a result of the strong binding. Electronic absorption spectroscopy, mass spectrometry and computational analysis are a powerful combination in understanding possible chemical reactions in vivo and this information can be used to synthetically tune dirhodium complexes for use in the fight against cancer.
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Affiliation(s)
- Daisy L Wong
- Stillman Bioinorganic Group, Department of Chemistry, University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7, Canada.
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13
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Enriquez Garcia A, Jalilehvand F. Aerobic reactions of antitumor active dirhodium(II) tetraacetate Rh 2(CH 3COO) 4 with glutathione. J Biol Inorg Chem 2018; 23:231-239. [PMID: 29214420 PMCID: PMC5816706 DOI: 10.1007/s00775-017-1524-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 11/29/2017] [Indexed: 12/27/2022]
Abstract
The aerobic reaction between glutathione (H3A) and dirhodium(II) tetraacetate, Rh2(AcO)4 (AcO- = CH3COO-), in aqueous solution (pH 7.4) breaks up the direct RhII-RhII bond and its carboxylate framework, as evidenced by UV-Vis spectroscopy. After purifying the reaction product using size exclusion chromatography, electrospray ionization mass spectrometry (ESI-MS) of the solution showed binuclear [Formula: see text] and [Formula: see text] ions. Evaporation yielded a solid compound, [Formula: see text], for which Rh K-edge extended X-ray absorption fine structure (EXAFS) spectroscopy revealed ~ 2 Rh-O (2.08 ± 0.02 Å) and ~ 4 Rh-S (2.33 ± 0.02 Å) bond distances around each RhIII center, and the RhIII··RhIII distance 3.11 ± 0.02 Å, close to that in dirhodium(III) complexes with three bridging thiolates connecting [Formula: see text] units. The 13C CPMAS NMR spectrum of the RhIII-glutathione complex showed a change ∆δ C > 6 ppm in the chemical shift of the COO- signal, indicating some carboxylate coordination to the Rh(III) ions. This study shows that under aerobic conditions glutathione enables oxidation of Rh2(AcO)4 and thus reduces its antitumor efficiency. The reaction of Rh2(AcO)4 with glutathione was investigated by ESI-MS, UV-Vis, 13C NMR and X-ray absorption spectroscopy, revealing that glutathione breaks down the carboxylate framework enabling oxidization of the [Formula: see text] core to Rh(III) dimeric units, bridged by three thiolates.
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Affiliation(s)
- Alejandra Enriquez Garcia
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada
| | - Farideh Jalilehvand
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada.
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Wong DL, Stillman MJ. Capturing platinum in cisplatin: kinetic reactions with recombinant human apo-metallothionein 1a. Metallomics 2018; 10:713-721. [DOI: 10.1039/c8mt00029h] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Detailed mass spectra data show the stepwise sequence of cisplatin deconstruction by apo-metallothionein.
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Affiliation(s)
- Daisy L. Wong
- Stillman Bioinorganic Group
- Department of Chemistry
- The University of Western Ontario, London
- Ontario
- Canada N6A 5B7
| | - Martin J. Stillman
- Stillman Bioinorganic Group
- Department of Chemistry
- The University of Western Ontario, London
- Ontario
- Canada N6A 5B7
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15
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Nišavić M, Janjić GV, Hozić A, Petković M, Milčić MK, Vujčić Z, Cindrić M. Positive and negative nano-electrospray mass spectrometry of ruthenated serum albumin supported by docking studies: an integrated approach towards defining metallodrug binding sites on proteins. Metallomics 2018; 10:587-594. [DOI: 10.1039/c7mt00330g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Negative mode nanoLC/nano ESI MS was used for determing Ru(ii) binding sites on protein.
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Affiliation(s)
- Marija Nišavić
- Department of Physical Chemistry
- “Vinča” Institute of Nuclear Sciences
- University of Belgrade
- 11000 Belgrade
- Serbia
| | - Goran V. Janjić
- Institute of Chemistry, Technology and Metallurgy
- University of Belgrade
- 11000 Belgrade
- Serbia
| | - Amela Hozić
- Centre for Proteomics and Mass Spectrometry
- Division of Molecular Medicine
- Ruđer Bošković Institute
- 10000 Zagreb
- Croatia
| | - Marijana Petković
- Department of Physical Chemistry
- “Vinča” Institute of Nuclear Sciences
- University of Belgrade
- 11000 Belgrade
- Serbia
| | - Miloš K. Milčić
- Faculty of Chemistry
- University of Belgrade
- 11000 Belgrade
- Serbia
| | - Zoran Vujčić
- Faculty of Chemistry
- University of Belgrade
- 11000 Belgrade
- Serbia
| | - Mario Cindrić
- Centre for Proteomics and Mass Spectrometry
- Division of Molecular Medicine
- Ruđer Bošković Institute
- 10000 Zagreb
- Croatia
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