1
|
Islam S, Parves MR, Islam MJ, Ali MA, Efaz FM, Hossain MS, Ullah MO, Halim MA. Structural and functional effects of the L84S mutant in the SARS-COV-2 ORF8 dimer based on microsecond molecular dynamics study. J Biomol Struct Dyn 2024; 42:5770-5787. [PMID: 37403295 DOI: 10.1080/07391102.2023.2228919] [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: 01/10/2023] [Accepted: 06/17/2023] [Indexed: 07/06/2023]
Abstract
The L84S mutation has been observed frequently in the ORF8 protein of SARS-CoV-2, which is an accessory protein involved in various important functions such as virus propagation, pathogenesis, and evading the immune response. However, the specific effects of this mutation on the dimeric structure of ORF8 and its impacts on interactions with host components and immune responses are not well understood. In this study, we performed one microsecond molecular dynamics (MD) simulation and analyzed the dimeric behavior of the L84S and L84A mutants in comparison to the native protein. The MD simulations revealed that both mutations caused changes in the conformation of the ORF8 dimer, influenced protein folding mechanisms, and affected the overall structural stability. In particular, the 73YIDI76 motif has found to be significantly affected by the L84S mutation, leading to structural flexibility in the region connecting the C-terminal β4 and β5 strands. This flexibility might be responsible for virus immune modulation. The free energy landscape (FEL) and principle component analysis (PCA) have also supported our investigation. Overall, the L84S and L84A mutations affect the ORF8 dimeric interfaces by reducing the frequency of protein-protein interacting residues (Arg52, Lys53, Arg98, Ile104, Arg115, Val117, Asp119, Phe120, and Ile121) in the ORF8 dimer. Our findings provide detail insights for further research in designing structure-based therapeutics against the SARS-CoV-2.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Shafiqul Islam
- Division of Infectious disease and Division of Computer Aided Drug Design, The Red-Green Research Centre, Dhaka, Bangladesh
| | - Md Rimon Parves
- Division of Infectious disease and Division of Computer Aided Drug Design, The Red-Green Research Centre, Dhaka, Bangladesh
| | - Md Jahirul Islam
- Division of Infectious disease and Division of Computer Aided Drug Design, The Red-Green Research Centre, Dhaka, Bangladesh
| | - Md Ackas Ali
- Department of Chemistry and Biochemistry, Kennesaw State University, Kennesaw, GA, USA
| | - Faiyaz Md Efaz
- Division of Infectious disease and Division of Computer Aided Drug Design, The Red-Green Research Centre, Dhaka, Bangladesh
| | - Md Shahadat Hossain
- Division of Infectious disease and Division of Computer Aided Drug Design, The Red-Green Research Centre, Dhaka, Bangladesh
| | - M Obayed Ullah
- Division of Infectious disease and Division of Computer Aided Drug Design, The Red-Green Research Centre, Dhaka, Bangladesh
| | - Mohammad A Halim
- Department of Chemistry and Biochemistry, Kennesaw State University, Kennesaw, GA, USA
| |
Collapse
|
2
|
Fortino M, Arnesano F, Pietropaolo A. Unraveling Copper Exchange in the Atox1-Cu(I)-Mnk1 Heterodimer: A Simulation Approach. J Phys Chem B 2024; 128:5336-5343. [PMID: 38780400 DOI: 10.1021/acs.jpcb.4c01026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
Copper, an essential metal for various cellular processes, requires tight regulation to prevent cytotoxicity. Intracellular pathways crucial for maintaining optimal copper levels involve soluble and membrane transporters, namely, metallochaperones and P-type ATPases, respectively. In this study, we used a simulation workflow based on free-energy perturbation (FEP) theory and parallel bias metadynamics (PBMetaD) to predict the Cu(I) exchange mechanism between the human Cu(I) chaperone, Atox1, and one of its two physiological partners, ATP7A. ATP7A, also known as the Menkes disease protein, is a transmembrane protein and one of the main copper-transporting ATPases. It pumps copper into the trans-Golgi network for the maturation of cuproenzymes and is also essential for the efflux of excess copper across the plasma membrane. In this analysis, we utilized the nuclear magnetic resonance (NMR) structure of the Cu(I)-mediated complex between Atox1 and the first soluble domain of the Menkes protein (Mnk1) as a starting point. Independent free-energy simulations were conducted to investigate the dissociation of both Atox1 and Mnk1. The calculations revealed that the two dissociations require free energy values of 6.3 and 6.2 kcal/mol, respectively, following a stepwise dissociation mechanism.
Collapse
Affiliation(s)
- Mariagrazia Fortino
- Dipartimento di Scienze della Salute, Università Magna Graecia di Catanzaro, Viale Europa, 88100 Catanzaro, Italy
| | - Fabio Arnesano
- Dipartimento di Chimica, Università di Bari "Aldo Moro", Via Orabona 4, 70125 Bari, Italy
| | - Adriana Pietropaolo
- Dipartimento di Scienze della Salute, Università Magna Graecia di Catanzaro, Viale Europa, 88100 Catanzaro, Italy
| |
Collapse
|
3
|
Shenberger Y, Gevorkyan-Airapetov L, Hirsch M, Hofmann L, Ruthstein S. An in-cell spin-labelling methodology provides structural information on cytoplasmic proteins in bacteria. Chem Commun (Camb) 2023; 59:10524-10527. [PMID: 37563959 DOI: 10.1039/d3cc03047d] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/12/2023]
Abstract
EPR in-cell spin-labeling was applied to CueR in E. coli. The methodology employed a Cu(II)-NTA complexed with dHis. High resolved in-cell distance distributions were obtained revealing minor differences between in vitro and in-cell data. This methodology allows study of structural changes of any protein in-cell, independent of size or cellular system.
Collapse
Affiliation(s)
- Yulia Shenberger
- Department of Chemistry, Faculty of Exact Sciences and Institute of Nanotechnology and Advanced Materials, Bar Ilan university, 5290002, Israel.
| | - Lada Gevorkyan-Airapetov
- Department of Chemistry, Faculty of Exact Sciences and Institute of Nanotechnology and Advanced Materials, Bar Ilan university, 5290002, Israel.
| | - Melanie Hirsch
- Department of Chemistry, Faculty of Exact Sciences and Institute of Nanotechnology and Advanced Materials, Bar Ilan university, 5290002, Israel.
| | - Lukas Hofmann
- Department of Chemistry, Faculty of Exact Sciences and Institute of Nanotechnology and Advanced Materials, Bar Ilan university, 5290002, Israel.
| | - Sharon Ruthstein
- Department of Chemistry, Faculty of Exact Sciences and Institute of Nanotechnology and Advanced Materials, Bar Ilan university, 5290002, Israel.
| |
Collapse
|
4
|
Hardebeck S, Schreiber S, Adick A, Langer K, Jose J. A FRET-Based Assay for the Identification of PCNA Inhibitors. Int J Mol Sci 2023; 24:11858. [PMID: 37511614 PMCID: PMC10380293 DOI: 10.3390/ijms241411858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 07/19/2023] [Accepted: 07/20/2023] [Indexed: 07/30/2023] Open
Abstract
Proliferating cell nuclear antigen (PCNA) is the key regulator of human DNA metabolism. One important interaction partner is p15, involved in DNA replication and repair. Targeting the PCNA-p15 interaction is a promising therapeutic strategy against cancer. Here, a Förster resonance energy transfer (FRET)-based assay for the analysis of the PCNA-p15 interaction was developed. Next to the application as screening tool for the identification and characterization of PCNA-p15 interaction inhibitors, the assay is also suitable for the investigation of mutation-induced changes in their affinity. This is particularly useful for analyzing disease associated PCNA or p15 variants at the molecular level. Recently, the PCNA variant C148S has been associated with Ataxia-telangiectasia-like disorder type 2 (ATLD2). ATLD2 is a neurodegenerative disease based on defects in DNA repair due to an impaired PCNA. Incubation time dependent FRET measurements indicated no effect on PCNAC148S-p15 affinity, but on PCNA stability. The impaired stability and increased aggregation behavior of PCNAC148S was confirmed by intrinsic tryptophan fluorescence, differential scanning fluorimetry (DSF) and asymmetrical flow field-flow fractionation (AF4) measurements. The analysis of the disease associated PCNA variant demonstrated the versatility of the interaction assay as developed.
Collapse
Affiliation(s)
- Sarah Hardebeck
- University of Münster, Institute of Pharmaceutical and Medicinal Chemistry, Pharmacampus, 48149 Münster, Germany
| | - Sebastian Schreiber
- University of Münster, Institute of Pharmaceutical and Medicinal Chemistry, Pharmacampus, 48149 Münster, Germany
| | - Annika Adick
- University of Münster, Institute for Pharmaceutical Technology and Biopharmacy, Pharmacampus, 48149 Münster, Germany
| | - Klaus Langer
- University of Münster, Institute for Pharmaceutical Technology and Biopharmacy, Pharmacampus, 48149 Münster, Germany
| | - Joachim Jose
- University of Münster, Institute of Pharmaceutical and Medicinal Chemistry, Pharmacampus, 48149 Münster, Germany
| |
Collapse
|
5
|
Fortino M, Schifino G, Vitone D, Arnesano F, Pietropaolo A. The stepwise dissociation of the Zn(II)-bound Atox1 homodimer and its energetic asymmetry. Inorganica Chim Acta 2023. [DOI: 10.1016/j.ica.2023.121452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
|
6
|
Qasem Z, Pavlin M, Ritacco I, Avivi MY, Meron S, Hirsch M, Shenberger Y, Gevorkyan-Airapetov L, Magistrato A, Ruthstein S. Disrupting Cu trafficking as a potential therapy for cancer. Front Mol Biosci 2022; 9:1011294. [PMID: 36299299 PMCID: PMC9589254 DOI: 10.3389/fmolb.2022.1011294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 09/26/2022] [Indexed: 11/13/2022] Open
Abstract
Copper ions play a crucial role in various cellular biological processes. However, these copper ions can also lead to toxicity when their concentration is not controlled by a sophisticated copper-trafficking system. Copper dys-homeostasis has been linked to a variety of diseases, including neurodegeneration and cancer. Therefore, manipulating Cu-trafficking to trigger selective cancer cell death may be a viable strategy with therapeutic benefit. By exploiting combined in silico and experimental strategies, we identified small peptides able to bind Atox1 and metal-binding domains 3-4 of ATP7B proteins. We found that these peptides reduced the proliferation of cancer cells owing to increased cellular copper ions concentration. These outcomes support the idea of harming copper trafficking as an opportunity for devising novel anti-cancer therapies.
Collapse
Affiliation(s)
- Zena Qasem
- Department of Chemistry and the Institute of Nanotechnology and Advanced Materials (BINA), Bar-Ilan University, Ramat-Gan, Israel
| | - Matic Pavlin
- National Research Council of Italy (CNR)—Institute of Material (IOM) C/o International School for Advanced Studies (SISSA), Trieste, Italy
- Department of Catalysis and Chemical Reaction Engineering, National Institute of Chemistry, Ljubljana, Slovenia
| | - Ida Ritacco
- National Research Council of Italy (CNR)—Institute of Material (IOM) C/o International School for Advanced Studies (SISSA), Trieste, Italy
- Department of Chemistry, University of Salerno, Salerno, Italy
| | - Matan Y. Avivi
- The Mina and Everard Goodman Faculty of Life-Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Shelly Meron
- Department of Chemistry and the Institute of Nanotechnology and Advanced Materials (BINA), Bar-Ilan University, Ramat-Gan, Israel
| | - Melanie Hirsch
- Department of Chemistry and the Institute of Nanotechnology and Advanced Materials (BINA), Bar-Ilan University, Ramat-Gan, Israel
| | - Yulia Shenberger
- Department of Chemistry and the Institute of Nanotechnology and Advanced Materials (BINA), Bar-Ilan University, Ramat-Gan, Israel
| | - Lada Gevorkyan-Airapetov
- Department of Chemistry and the Institute of Nanotechnology and Advanced Materials (BINA), Bar-Ilan University, Ramat-Gan, Israel
| | - Alessandra Magistrato
- National Research Council of Italy (CNR)—Institute of Material (IOM) C/o International School for Advanced Studies (SISSA), Trieste, Italy
- *Correspondence: Alessandra Magistrato, ; Sharon Ruthstein,
| | - Sharon Ruthstein
- Department of Chemistry and the Institute of Nanotechnology and Advanced Materials (BINA), Bar-Ilan University, Ramat-Gan, Israel
- *Correspondence: Alessandra Magistrato, ; Sharon Ruthstein,
| |
Collapse
|
7
|
Bridging H2O and H2S homomeric clusters via H2O-H2S mixed clusters: Impact of the changing ratio of H2O and H2S moieties. COMPUT THEOR CHEM 2022. [DOI: 10.1016/j.comptc.2022.113740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
8
|
Janoš P, Aupič J, Ruthstein S, Magistrato A. The conformational plasticity of the selectivity filter methionines controls the in-cell Cu(I) uptake through the CTR1 transporter. QRB DISCOVERY 2022; 3:e3. [PMID: 37529280 PMCID: PMC10392627 DOI: 10.1017/qrd.2022.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 03/25/2022] [Accepted: 04/01/2022] [Indexed: 11/05/2022] Open
Abstract
Copper is a trace element vital to many cellular functions. Yet its abnormal levels are toxic to cells, provoking a variety of severe diseases. The high affinity copper transporter 1 (CTR1), being the main in-cell copper [Cu(I)] entry route, tightly regulates its cellular uptake via a still elusive mechanism. Here, all-atoms simulations unlock the molecular terms of Cu(I) transport in eukaryotes disclosing that the two methionine (Met) triads, forming the selectivity filter, play an unprecedented dual role both enabling selective Cu(I) transport and regulating its uptake rate thanks to an intimate coupling between the conformational plasticity of their bulky side chains and the number of bound Cu(I) ions. Namely, the Met residues act as a gate reducing the Cu(I) import rate when two ions simultaneously bind to CTR1. This may represent an elegant autoregulatory mechanism through which CTR1 protects the cells from excessively high, and hence toxic, in-cell Cu(I) levels. Overall, our outcomes resolve fundamental questions in CTR1 biology and open new windows of opportunity to tackle diseases associated with an imbalanced copper uptake.
Collapse
Affiliation(s)
- Pavel Janoš
- Consiglio Nazionale delle ricerche/National Research Council (CNR) -IOM c/o International School for Advanced Studies (SISSA/ISAS), via Bonomea 265, 34136Trieste, Italy
| | - Jana Aupič
- Consiglio Nazionale delle ricerche/National Research Council (CNR) -IOM c/o International School for Advanced Studies (SISSA/ISAS), via Bonomea 265, 34136Trieste, Italy
| | - Sharon Ruthstein
- Department of Chemistry, Faculty of Exact Sciences and the Institute for Nanotechnology and Advanced Materials (BINA), Bar-Ilan University, 5290002Ramat-Gan, Israel
| | - Alessandra Magistrato
- Consiglio Nazionale delle ricerche/National Research Council (CNR) -IOM c/o International School for Advanced Studies (SISSA/ISAS), via Bonomea 265, 34136Trieste, Italy
| |
Collapse
|
9
|
Spinello A, Borišek J, Pavlin M, Janoš P, Magistrato A. Computing Metal-Binding Proteins for Therapeutic Benefit. ChemMedChem 2021; 16:2034-2049. [PMID: 33740297 DOI: 10.1002/cmdc.202100109] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Indexed: 01/18/2023]
Abstract
Over one third of biomolecules rely on metal ions to exert their cellular functions. Metal ions can play a structural role by stabilizing the structure of biomolecules, a functional role by promoting a wide variety of biochemical reactions, and a regulatory role by acting as messengers upon binding to proteins regulating cellular metal-homeostasis. These diverse roles in biology ascribe critical implications to metal-binding proteins in the onset of many diseases. Hence, it is of utmost importance to exhaustively unlock the different mechanistic facets of metal-binding proteins and to harness this knowledge to rationally devise novel therapeutic strategies to prevent or cure pathological states associated with metal-dependent cellular dysfunctions. In this compendium, we illustrate how the use of a computational arsenal based on docking, classical, and quantum-classical molecular dynamics simulations can contribute to extricate the minutiae of the catalytic, transport, and inhibition mechanisms of metal-binding proteins at the atomic level. This knowledge represents a fertile ground and an essential prerequisite for selectively targeting metal-binding proteins with small-molecule inhibitors aiming to (i) abrogate deregulated metal-dependent (mis)functions or (ii) leverage metal-dyshomeostasis to selectively trigger harmful cells death.
Collapse
Affiliation(s)
- Angelo Spinello
- National Research Council of Italy (CNR)-, Institute of Materials (IOM) c/o International School for Advanced Studies (SISSA), via Bonomea 265, 34136, Trieste, Italy
| | - Jure Borišek
- National Institute of Chemistry Institution Hajdrihova ulica 19, 1000, Ljubljana, Slovenia
| | - Matic Pavlin
- Laboratory of Microsensor Structures and Electronics Faculty of Electrical Engineering, University of Ljubljana Tržaška cesta 25, 1000, Ljubljana, Slovenia
| | - Pavel Janoš
- National Research Council of Italy (CNR)-, Institute of Materials (IOM) c/o International School for Advanced Studies (SISSA), via Bonomea 265, 34136, Trieste, Italy
| | - Alessandra Magistrato
- National Research Council of Italy (CNR)-, Institute of Materials (IOM) c/o International School for Advanced Studies (SISSA), via Bonomea 265, 34136, Trieste, Italy
| |
Collapse
|
10
|
Roles of RcsA, an AhpD Family Protein, in Reactive Chlorine Stress Resistance and Virulence in Pseudomonas aeruginosa. Appl Environ Microbiol 2020; 86:AEM.01480-20. [PMID: 32801171 DOI: 10.1128/aem.01480-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 08/03/2020] [Indexed: 11/20/2022] Open
Abstract
Reactive chlorine species (RCS), particularly hypochlorous acid (HOCl), are powerful antimicrobial oxidants generated by biological pathways and chemical syntheses. Pseudomonas aeruginosa is an important opportunistic pathogen that has adapted mechanisms for protection and survival in harsh environments, including RCS exposure. Based on previous transcriptomic studies of HOCl exposure in P. aeruginosa, we found that the expression of PA0565, or rcsA, which encodes an alkyl hydroperoxidase D-like protein, exhibited the highest induction among the RCS-induced genes. In this study, rcsA expression was dominant under HOCl stress and greatly increased under HOCl-related stress conditions. Functional analysis of RcsA showed that the distinguishing core amino acid residues Cys60, Cys63, and His67 were required for the degradation of sodium hypochlorite (NaOCl), suggesting an extended motif in the AhpD family. After allelic exchange mutagenesis in the P. aeruginosa rcsA, the P. aeruginosa rcsA deletion mutant showed significantly decreased HOCl resistance. Ectopic expression of P. aeruginosa rcsA led to significantly increased NaOCl resistance in Escherichia coli Moreover, the pathogenicity of the rcsA mutant decreased dramatically in both Caenorhabditis elegans and Drosophila melanogaster host model systems compared to the wild type (WT). Finally, the Cys60, Cys63, and His67 variants of RcsA were unsuccessful at complementing phenotypes of the rcsA mutant. Overall, our data indicate the importance of P. aeruginosa RcsA in defense against HOCl stress under disinfections and during infections of hosts, which involves the catalytic Cys60, Cys63, and His67 residues.IMPORTANCE Pseudomonas aeruginosa is a common pathogen that is a major cause of serious infections in many hosts. Hypochlorous acid (HOCl) is a potent antimicrobial agent found in household bleach and is a widely used disinfectant. P. aeruginosa has evolved adaptive mechanisms for protection and survival during HOCl exposure. We identified P. aeruginosa rcsA as a HOCl-responsive gene encoding an antioxidant protein that may be involved in HOCl degradation. RcsA has a distinguishing core motif containing functional Cys60, Cys63, and His67 residues. P. aeruginosa rcsA plays an important role in bleach tolerance, with expression of P. aeruginosa rcsA in Escherichia coli also conferring HOCl resistance. Interestingly, RcsA is required for full virulence in worm and fruit fly infection models, indicating a correlation between mechanisms of bleach toxicity and host immunity during infection. This provides new insights into the mechanisms used by P. aeruginosa to persist in harsh environments such as hospitals.
Collapse
|
11
|
Zaccak M, Qasem Z, Gevorkyan-Airapetov L, Ruthstein S. An EPR Study on the Interaction between the Cu(I) Metal Binding Domains of ATP7B and the Atox1 Metallochaperone. Int J Mol Sci 2020; 21:ijms21155536. [PMID: 32748830 PMCID: PMC7432781 DOI: 10.3390/ijms21155536] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 07/29/2020] [Accepted: 07/30/2020] [Indexed: 02/07/2023] Open
Abstract
Copper’s essentiality and toxicity mean it requires a sophisticated regulation system for its acquisition, cellular distribution and excretion, which until now has remained elusive. Herein, we applied continuous wave (CW) and pulsed electron paramagnetic resonance (EPR) spectroscopy in solution to resolve the copper trafficking mechanism in humans, by considering the route travelled by Cu(I) from the metallochaperone Atox1 to the metal binding domains of ATP7B. Our study revealed that Cu(I) is most likely mediated by the binding of the Atox1 monomer to metal binding domain 1 (MBD1) and MBD4 of ATP7B in the final part of its extraction pathway, while the other MBDs mediate this interaction and participate in copper transfer between the various MBDs to the ATP7B membrane domain. This research also proposes that MBD1-3 and MBD4-6 act as two independent units.
Collapse
|
12
|
Dreyer A, Schackmann A, Kriznik A, Chibani K, Wesemann C, Vogelsang L, Beyer A, Dietz KJ. Thiol Redox Regulation of Plant β-Carbonic Anhydrase. Biomolecules 2020; 10:E1125. [PMID: 32751472 PMCID: PMC7463553 DOI: 10.3390/biom10081125] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 07/27/2020] [Accepted: 07/28/2020] [Indexed: 12/16/2022] Open
Abstract
β-carbonic anhydrases (βCA) accelerate the equilibrium formation between CO2 and carbonate. Two plant βCA isoforms are targeted to the chloroplast and represent abundant proteins in the range of >1% of chloroplast protein. While their function in gas exchange and photosynthesis is well-characterized in carbon concentrating mechanisms of cyanobacteria and plants with C4-photosynthesis, their function in plants with C3-photosynthesis is less clear. The presence of conserved and surface-exposed cysteinyl residues in the βCA-structure urged to the question whether βCA is subject to redox regulation. Activity measurements revealed reductive activation of βCA1, whereas oxidized βCA1 was inactive. Mutation of cysteinyl residues decreased βCA1 activity, in particular C280S, C167S, C230S, and C257S. High concentrations of dithiothreitol or low amounts of reduced thioredoxins (TRXs) activated oxidized βCA1. TRX-y1 and TRX-y2 most efficiently activated βCA1, followed by TRX-f1 and f2 and NADPH-dependent TRX reductase C (NTRC). High light irradiation did not enhance βCA activity in wildtype Arabidopsis, but surprisingly in βca1 knockout plants, indicating light-dependent regulation. The results assign a role of βCA within the thiol redox regulatory network of the chloroplast.
Collapse
Affiliation(s)
- Anna Dreyer
- Department of Biochemistry and Physiology of Plants, Faculty of Biology, University of Bielefeld, 33615 Bielefeld, Germany; (A.D.); (A.S.); (K.C.); (C.W.); (L.V.)
| | - Alexander Schackmann
- Department of Biochemistry and Physiology of Plants, Faculty of Biology, University of Bielefeld, 33615 Bielefeld, Germany; (A.D.); (A.S.); (K.C.); (C.W.); (L.V.)
| | - Alexandre Kriznik
- CNRS, INSERM, IBSLor, Biophysics and Structural Biology, Université de Lorraine, F-5400 Nancy, France;
| | - Kamel Chibani
- Department of Biochemistry and Physiology of Plants, Faculty of Biology, University of Bielefeld, 33615 Bielefeld, Germany; (A.D.); (A.S.); (K.C.); (C.W.); (L.V.)
| | - Corinna Wesemann
- Department of Biochemistry and Physiology of Plants, Faculty of Biology, University of Bielefeld, 33615 Bielefeld, Germany; (A.D.); (A.S.); (K.C.); (C.W.); (L.V.)
| | - Lara Vogelsang
- Department of Biochemistry and Physiology of Plants, Faculty of Biology, University of Bielefeld, 33615 Bielefeld, Germany; (A.D.); (A.S.); (K.C.); (C.W.); (L.V.)
| | - André Beyer
- Physics of Supramolecular Systems and Surfaces, Faculty of Physics, Bielefeld University, 33615 Bielefeld, Germany;
| | - Karl-Josef Dietz
- Department of Biochemistry and Physiology of Plants, Faculty of Biology, University of Bielefeld, 33615 Bielefeld, Germany; (A.D.); (A.S.); (K.C.); (C.W.); (L.V.)
| |
Collapse
|
13
|
Perkal O, Qasem Z, Turgeman M, Schwartz R, Gevorkyan-Airapetov L, Pavlin M, Magistrato A, Major DT, Ruthstein S. Cu(I) Controls Conformational States in Human Atox1 Metallochaperone: An EPR and Multiscale Simulation Study. J Phys Chem B 2020; 124:4399-4411. [PMID: 32396355 PMCID: PMC7294806 DOI: 10.1021/acs.jpcb.0c01744] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
![]()
Atox1 is a human
copper metallochaperone that is responsible for
transferring copper ions from the main human copper transporter, hCtr1,
to ATP7A/B in the Golgi apparatus. Atox1 interacts with the Ctr1 C-terminal
domain as a dimer, although it transfers the copper ions to ATP7A/B
in a monomeric form. The copper binding site in the Atox1 dimer involves
Cys12 and Cys15, while Lys60 was also suggested to play a role in
the copper binding. We recently showed that Atox1 can adopt various
conformational states, depending on the interacting protein. In the
current study, we apply EPR experiments together with hybrid quantum
mechanics–molecular mechanics molecular dynamics simulations
using a recently developed semiempirical density functional theory
approach, to better understand the effect of Atox1’s conformational
states on copper coordination. We propose that the flexibility of
Atox1 occurs owing to protonation of one or more of the cysteine residues,
and that Cys15 is an important residue for Atox1 dimerization, while
Cys12 is a critical residue for Cu(I) binding. We also show that Lys60
electrostatically stabilizes the Cu(I)–Atox1 dimer.
Collapse
Affiliation(s)
- Ortal Perkal
- Department of Chemistry and Institute for Nanotechnology & Advanced Materials, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Zena Qasem
- Department of Chemistry, Faculty of Exact Sciences, Bar Ilan University, Ramat-Gan 5290002, Israel
| | - Meital Turgeman
- Department of Chemistry, Faculty of Exact Sciences, Bar Ilan University, Ramat-Gan 5290002, Israel
| | - Renana Schwartz
- Department of Chemistry and Institute for Nanotechnology & Advanced Materials, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Lada Gevorkyan-Airapetov
- Department of Chemistry, Faculty of Exact Sciences, Bar Ilan University, Ramat-Gan 5290002, Israel
| | - Matic Pavlin
- CNR-IOM at SISSA, via Bonomea 265, 34135, Trieste, Italy
| | | | - Dan Thomas Major
- Department of Chemistry and Institute for Nanotechnology & Advanced Materials, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Sharon Ruthstein
- Department of Chemistry, Faculty of Exact Sciences, Bar Ilan University, Ramat-Gan 5290002, Israel
| |
Collapse
|