1
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Bazayeva M, Andreini C, Rosato A. A database overview of metal-coordination distances in metalloproteins. Acta Crystallogr D Struct Biol 2024; 80:362-376. [PMID: 38682667 PMCID: PMC11066882 DOI: 10.1107/s2059798324003152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 04/11/2024] [Indexed: 05/01/2024] Open
Abstract
Metalloproteins are ubiquitous in all living organisms and take part in a very wide range of biological processes. For this reason, their experimental characterization is crucial to obtain improved knowledge of their structure and biological functions. The three-dimensional structure represents highly relevant information since it provides insight into the interaction between the metal ion(s) and the protein fold. Such interactions determine the chemical reactivity of the bound metal. The available PDB structures can contain errors due to experimental factors such as poor resolution and radiation damage. A lack of use of distance restraints during the refinement and validation process also impacts the structure quality. Here, the aim was to obtain a thorough overview of the distribution of the distances between metal ions and their donor atoms through the statistical analysis of a data set based on more than 115 000 metal-binding sites in proteins. This analysis not only produced reference data that can be used by experimentalists to support the structure-determination process, for example as refinement restraints, but also resulted in an improved insight into how protein coordination occurs for different metals and the nature of their binding interactions. In particular, the features of carboxylate coordination were inspected, which is the only type of interaction that is commonly present for nearly all metals.
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Affiliation(s)
- Milana Bazayeva
- Department of Chemistry, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
- Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Claudia Andreini
- Department of Chemistry, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
- Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
- Consorzio Interuniversitario di Risonanze Magnetiche di Metallo Proteine, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Antonio Rosato
- Department of Chemistry, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
- Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
- Consorzio Interuniversitario di Risonanze Magnetiche di Metallo Proteine, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
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2
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Sgueglia G, Vrettas MD, Chino M, De Simone A, Lombardi A. MetalHawk: Enhanced Classification of Metal Coordination Geometries by Artificial Neural Networks. J Chem Inf Model 2024; 64:2356-2367. [PMID: 37956388 PMCID: PMC11005052 DOI: 10.1021/acs.jcim.3c00873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 09/29/2023] [Accepted: 10/26/2023] [Indexed: 11/15/2023]
Abstract
The chemical properties of metal complexes are strongly dependent on the number and geometrical arrangement of ligands coordinated to the metal center. Existing methods for determining either coordination number or geometry rely on a trade-off between accuracy and computational costs, which hinders their application to the study of large structure data sets. Here, we propose MetalHawk (https://github.com/vrettasm/MetalHawk), a machine learning-based approach to perform simultaneous classification of metal site coordination number and geometry through artificial neural networks (ANNs), which were trained using the Cambridge Structural Database (CSD) and Metal Protein Data Bank (MetalPDB). We demonstrate that the CSD-trained model can be used to classify sites belonging to the most common coordination numbers and geometry classes with balanced accuracy equal to 96.51% for CSD-deposited metal sites. The CSD-trained model was also found to be capable of classifying bioinorganic metal sites from the MetalPDB database, with balanced accuracy equal to 84.29% on the whole PDB data set and to 91.66% on manually reviewed sites in the PDB validation set. Moreover, we report evidence that the output vectors of the CSD-trained model can be considered as a proxy indicator of metal-site distortions, showing that these can be interpreted as a low-dimensional representation of subtle geometrical features present in metal site structures.
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Affiliation(s)
- Gianmattia Sgueglia
- Department
of Chemical Sciences, University of Naples
Federico II, Via Cintia 21, 80126 Napoli, Italy
| | - Michail D. Vrettas
- Department
of Pharmacy, University of Naples Federico
II, Via Domenico Montesano
49, 80131 Napoli, Italy
| | - Marco Chino
- Department
of Chemical Sciences, University of Naples
Federico II, Via Cintia 21, 80126 Napoli, Italy
| | - Alfonso De Simone
- Department
of Pharmacy, University of Naples Federico
II, Via Domenico Montesano
49, 80131 Napoli, Italy
| | - Angela Lombardi
- Department
of Chemical Sciences, University of Naples
Federico II, Via Cintia 21, 80126 Napoli, Italy
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3
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Lin GY, Su YC, Huang YL, Hsin KY. MESPEUS: a database of metal coordination groups in proteins. Nucleic Acids Res 2024; 52:D483-D493. [PMID: 37941148 PMCID: PMC10767821 DOI: 10.1093/nar/gkad1009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 10/15/2023] [Accepted: 10/18/2023] [Indexed: 11/10/2023] Open
Abstract
MESPEUS is a freely accessible database which uses carefully selected metal coordination groups found in metalloprotein structures taken from the Protein Data Bank. The database contains geometrical information of metal sites within proteins, including 40 metal types. In order to completely determine the metal coordination, the symmetry-related units of a given protein structure are taken into account and are generated using the appropriate space group symmetry operations. This permits a more complete description of the metal coordination geometry by including all coordinating atoms. The user-friendly web interface allows users to directly search for a metal site of interest using several useful options, including searching for metal elements, metal-donor distances, coordination number, donor residue group, and structural resolution. These searches can be carried out singly or in combination. The details of a metal site and the metal site(s) in the whole structure can be graphically displayed using the interactive web interface. MESPEUS is automatically updated monthly by synchronizing with the PDB database. An investigation for the Mg-ATP interaction is given to demonstrate how MESPEUS can be used to extract information about metal sites by selecting structure and coordination features. MESPEUS is available at http://mespeus.nchu.edu.tw/.
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Affiliation(s)
- Geng-Yu Lin
- Department of Animal Science, National Chung Hsing University, Taichung 402, Taiwan
| | - Yu-Cheng Su
- Department of Animal Science, National Chung Hsing University, Taichung 402, Taiwan
| | - Yen Lin Huang
- Department of Animal Science, National Chung Hsing University, Taichung 402, Taiwan
| | - Kun-Yi Hsin
- Department of Animal Science, National Chung Hsing University, Taichung 402, Taiwan
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4
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Li J, He X, Gao S, Liang Y, Qi Z, Xi Q, Zuo Y, Xing Y. The Metal-binding Protein Atlas (MbPA): an integrated database for curating metalloproteins in all aspects. J Mol Biol 2023:168117. [PMID: 37086947 DOI: 10.1016/j.jmb.2023.168117] [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: 10/29/2022] [Revised: 04/14/2023] [Accepted: 04/17/2023] [Indexed: 04/24/2023]
Abstract
Metal-binding proteins are essential for the vital activities and engage in their roles by acting in concert with metal cations. MbPA (The Metal-binding Protein Atlas) is the most comprehensive resource up to now dedicated to curating metal-binding proteins. Currently, it contains 106373 entries and 440187 sites related to 54 metals and 8169 species. Users can view all metal-binding proteins and species-specific proteins in MbPA. There are also metal-proteomics data that quantitatively describes protein expression in different tissues and organs. By analyzing the data of the amino acid residues at the metal-binding site, it is found that about 80% of the metal ions tend to bind to cysteine, aspartic acid, glutamic acid, and histidine. Moreover, we use Diversity Measure to confirm that the diversity of metal-binding is specific in different area of periodic table, and further elucidate the binding modes of 19 transition metals on 20 amino acids. In addition, MbPA also embraces 6855 potential pathogenic mutations related to metalloprotein. The resource is freely available at http://bioinfor.imu.edu.cn/mbpa.
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Affiliation(s)
- Jinzhao Li
- The Key Laboratory of Mammalian Reproductive Biology and Biotechnology of the Ministry of Education, College of life sciences, Inner Mongolia University, Hohhot, 010021, China
| | - Xiang He
- The Key Laboratory of Mammalian Reproductive Biology and Biotechnology of the Ministry of Education, College of life sciences, Inner Mongolia University, Hohhot, 010021, China
| | - Shuang Gao
- The Key Laboratory of Mammalian Reproductive Biology and Biotechnology of the Ministry of Education, College of life sciences, Inner Mongolia University, Hohhot, 010021, China
| | - Yuchao Liang
- The Key Laboratory of Mammalian Reproductive Biology and Biotechnology of the Ministry of Education, College of life sciences, Inner Mongolia University, Hohhot, 010021, China
| | - Zhi Qi
- The Key Laboratory of Mammalian Reproductive Biology and Biotechnology of the Ministry of Education, College of life sciences, Inner Mongolia University, Hohhot, 010021, China; Key Laboratory of Forage and Endemic Crop Biotechnology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010021, China
| | - Qilemuge Xi
- The Key Laboratory of Mammalian Reproductive Biology and Biotechnology of the Ministry of Education, College of life sciences, Inner Mongolia University, Hohhot, 010021, China
| | - Yongchun Zuo
- The Key Laboratory of Mammalian Reproductive Biology and Biotechnology of the Ministry of Education, College of life sciences, Inner Mongolia University, Hohhot, 010021, China.
| | - Yongqiang Xing
- The Inner Mongolia Key Laboratory of Functional Genome Bioinformatics, School of Life Science and Technology, Inner Mongolia University of Science and Technology, Baotou 014010, China.
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5
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Gerard T, Wei Y, Weerawardhana E, Lugosan A, Zeller M, Dickie DA, Li P, Lee WT. An Inorganic Fluorescent Chemosensor: Rational Design and Selective Mg 2+ Detection. ACS OMEGA 2023; 8:3835-3841. [PMID: 36743003 PMCID: PMC9893466 DOI: 10.1021/acsomega.2c06058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 11/16/2022] [Indexed: 06/18/2023]
Abstract
A Zn2+ based complex, 3, displays greatly increased fluorescence emission in the presence of Mg2+. Fluorescent and computational studies suggest that 3 selectively interacts with Mg2+ due to optimal cavity size formation between two uncoordinated pyrazole side arms. This work thus represents a new approach to the development of fluorescent chemosensors.
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Affiliation(s)
- Theodore Gerard
- Department
of Chemistry and Biochemistry, Loyola University
Chicago, Chicago, Illinois 60660, United States
| | - Yang Wei
- Department
of Chemistry and Biochemistry, Loyola University
Chicago, Chicago, Illinois 60660, United States
| | - Erwin Weerawardhana
- Department
of Chemistry and Biochemistry, Loyola University
Chicago, Chicago, Illinois 60660, United States
| | - Adriana Lugosan
- Department
of Chemistry and Biochemistry, Loyola University
Chicago, Chicago, Illinois 60660, United States
| | - Matthias Zeller
- Department
of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Diane A. Dickie
- Department
of Chemistry, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Pengfei Li
- Department
of Chemistry and Biochemistry, Loyola University
Chicago, Chicago, Illinois 60660, United States
| | - Wei-Tsung Lee
- Department
of Chemistry and Biochemistry, Loyola University
Chicago, Chicago, Illinois 60660, United States
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6
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Hosseinzadeh B, Ahmadi M. Coordination geometry in metallo-supramolecular polymer networks. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214733] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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7
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A Comprehensive Review of Computation-Based Metal-Binding Prediction Approaches at the Residue Level. BIOMED RESEARCH INTERNATIONAL 2022; 2022:8965712. [PMID: 35402609 PMCID: PMC8989566 DOI: 10.1155/2022/8965712] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Accepted: 03/04/2022] [Indexed: 12/29/2022]
Abstract
Clear evidence has shown that metal ions strongly connect and delicately tune the dynamic homeostasis in living bodies. They have been proved to be associated with protein structure, stability, regulation, and function. Even small changes in the concentration of metal ions can shift their effects from natural beneficial functions to harmful. This leads to degenerative diseases, malignant tumors, and cancers. Accurate characterizations and predictions of metalloproteins at the residue level promise informative clues to the investigation of intrinsic mechanisms of protein-metal ion interactions. Compared to biophysical or biochemical wet-lab technologies, computational methods provide open web interfaces of high-resolution databases and high-throughput predictors for efficient investigation of metal-binding residues. This review surveys and details 18 public databases of metal-protein binding. We collect a comprehensive set of 44 computation-based methods and classify them into four categories, namely, learning-, docking-, template-, and meta-based methods. We analyze the benchmark datasets, assessment criteria, feature construction, and algorithms. We also compare several methods on two benchmark testing datasets and include a discussion about currently publicly available predictive tools. Finally, we summarize the challenges and underlying limitations of the current studies and propose several prospective directions concerning the future development of the related databases and methods.
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8
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Tran JB, Krężel A. InterMetalDB: A Database and Browser of Intermolecular Metal Binding Sites in Macromolecules with Structural Information. J Proteome Res 2021; 20:1889-1901. [PMID: 33502860 PMCID: PMC8023803 DOI: 10.1021/acs.jproteome.0c00906] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
InterMetalDB is a
free-of-charge database and browser of intermolecular
metal binding sites that are present on the interfaces of macromolecules
forming larger assemblies based on structural information deposited
in Protein Data Bank (PDB). It can be found and freely used at https://intermetaldb.biotech.uni.wroc.pl/. InterMetalDB collects the interfacial binding sites with involvement
of metal ions and clusters them on the basis of 50% sequence similarity
and the nearest metal environment (5 Å radius). The data are
available through the web interface where they can be queried, viewed,
and downloaded. Complexity of the query depends on the user, because
the questions in the query are connected with each other by a logical
AND. InterMetalDB offers several useful options for filtering records
including searching for structures by particular parameters such as
structure resolution, structure description, and date of deposition.
Records can be filtered by coordinated metal ion, number of bound
amino acid residues, coordination sphere, and other features. InterMetalDB
is regularly updated and will continue to be regularly updated with
new content in the future. InterMetalDB is a useful tool for all researchers
interested in metalloproteins, protein engineering, and metal-driven
oligomerization.
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Affiliation(s)
- Józef Ba Tran
- Department of Chemical Biology, Faculty of Biotechnology, University of Wrocław, F. Joliot-Curie 14a, 50-383 Wrocław, Poland
| | - Artur Krężel
- Department of Chemical Biology, Faculty of Biotechnology, University of Wrocław, F. Joliot-Curie 14a, 50-383 Wrocław, Poland
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9
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Ben-Shushan S, Miller Y. Molecular Mechanisms and Aspects on the Role of Neuropeptide Y as a Zn 2+ and Cu 2+ Chelator. Inorg Chem 2021; 60:484-493. [PMID: 33320649 DOI: 10.1021/acs.inorgchem.0c03350] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The concept of metal chelation is based on simple coordination chemistry. The development of an ideal metal chelator that completely and selectively removes toxic metals from a specific metal binding site in proteins is required to prevent and or inhibit a variety of diseases, among them neurodegenerative diseases. This work examines neuropeptide Y (NPY) as a Zn2+ and Cu2+ chelator agent. NPY is a natural peptide that is produced in the human body; therefore, it is not a toxic agent and the complex that it forms is not toxic as well. Our simulations reveal that NPY has an efficient Zn2+ chelation activity but is less effective in chelating Cu2+. Moreover, while NPY demonstrates several conformations, the metal chelation occurs more efficiently in its native structure. Beyond the exploration of the activity of NPY as a Zn2+ and Cu2+ chelator agent, this work provides an insight into the molecular mechanisms of the chelation of these metals at the molecular level. The outcomes from this work may guide future experimental studies to examine NPY in metal chelation therapy for neurodegenerative diseases.
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Affiliation(s)
- Shira Ben-Shushan
- Department of Chemistry, Ben-Gurion University of the Negev, P.O. Box 653, Be'er Sheva 84105, Israel.,Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Be'er-Sheva 84105, Israel
| | - Yifat Miller
- Department of Chemistry, Ben-Gurion University of the Negev, P.O. Box 653, Be'er Sheva 84105, Israel.,Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Be'er-Sheva 84105, Israel
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10
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Investigation of manganese metal coordination in proteins: a comprehensive PDB analysis and quantum mechanical study. Struct Chem 2020. [DOI: 10.1007/s11224-020-01488-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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11
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Roskamp KW, Kozlyuk N, Sengupta S, Bierma JC, Martin RW. Divalent Cations and the Divergence of βγ-Crystallin Function. Biochemistry 2019; 58:4505-4518. [PMID: 31647219 DOI: 10.1021/acs.biochem.9b00507] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The βγ-crystallin superfamily contains both β- and γ-crystallins of the vertebrate eye lens and the microbial calcium-binding proteins, all of which are characterized by a common double-Greek key domain structure. The vertebrate βγ-crystallins are long-lived structural proteins that refract light onto the retina. In contrast, the microbial βγ-crystallins bind calcium ions. The βγ-crystallin from the tunicate Ciona intestinalis (Ci-βγ) provides a potential link between these two functions. It binds calcium with high affinity and is found in a light-sensitive sensory organ that is highly enriched in metal ions. Thus, Ci-βγ is valuable for investigating the evolution of the βγ-crystallin fold away from calcium binding and toward stability in the apo form as part of the vertebrate lens. Here, we investigate the effect of Ca2+ and other divalent cations on the stability and aggregation propensity of Ci-βγ and human γS-crystallin (HγS). Beyond Ca2+, Ci-βγ is capable of coordinating Mg2+, Sr2+, Co2+, Mn2+, Ni2+, and Zn2+, although only Sr2+ is bound with comparable affinity to its preferred metal ion. The extent to which the tested divalent cations stabilize Ci-βγ structure correlates strongly with ionic radius. In contrast, none of the tested divalent cations improved the stability of HγS, and some of them induced aggregation. Zn2+, Ni2+, and Co2+ induce aggregation by interacting with cysteine residues, whereas Cu2+-mediated aggregation proceeds via a different binding site.
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Affiliation(s)
- Kyle W Roskamp
- Department of Chemistry , University of California , Irvine , California 92697-2025 , United States
| | - Natalia Kozlyuk
- Department of Chemistry , University of California , Irvine , California 92697-2025 , United States
| | - Suvrajit Sengupta
- Department of Chemistry , University of California , Irvine , California 92697-2025 , United States
| | - Jan C Bierma
- Department of Molecular Biology and Biochemistry , University of California , Irvine , California 92697-3900 , United States
| | - Rachel W Martin
- Department of Chemistry , University of California , Irvine , California 92697-2025 , United States.,Department of Molecular Biology and Biochemistry , University of California , Irvine , California 92697-3900 , United States
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12
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Ireland SM, Martin ACR. ZincBind-the database of zinc binding sites. DATABASE-THE JOURNAL OF BIOLOGICAL DATABASES AND CURATION 2019; 2019:5304468. [PMID: 30722040 PMCID: PMC6361820 DOI: 10.1093/database/baz006] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 01/07/2019] [Indexed: 12/03/2022]
Abstract
Zinc is one of the most important biologically active metals. Ten per cent of the human genome is thought to encode a zinc binding protein and its uses encompass catalysis, structural stability, gene expression and immunity. At present, there is no specific resource devoted to identifying and presenting all currently known zinc binding sites. Here we present ZincBind, a database of zinc binding sites and its web front-end. Using the structural data in the Protein Data Bank, ZincBind identifies every instance of zinc binding to a protein, identifies its binding site and clusters sites based on 90% sequence identity. There are currently 24 992 binding sites, clustered into 7489 unique sites. The data are available over the web where they can be browsed and downloaded, and via a REST API. ZincBind is regularly updated and will continue to be updated with new data and features.
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Affiliation(s)
- Sam M Ireland
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Darwin Building, Gower Street, London, UK
| | - Andrew C R Martin
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Darwin Building, Gower Street, London, UK
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13
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Jiang T, Renfrew PD, Drew K, Youngs N, Butterfoss GL, Bonneau R, Shasha DN. An adaptive geometric search algorithm for macromolecular scaffold selection. Protein Eng Des Sel 2018; 31:345-354. [PMID: 30407584 PMCID: PMC6373690 DOI: 10.1093/protein/gzy028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 10/05/2018] [Indexed: 11/14/2022] Open
Abstract
A wide variety of protein and peptidomimetic design tasks require matching functional 3D motifs to potential oligomeric scaffolds. For example, during enzyme design, one aims to graft active-site patterns-typically consisting of 3-15 residues-onto new protein surfaces. Identifying protein scaffolds suitable for such active-site engraftment requires costly searches for protein folds that provide the correct side chain positioning to host the desired active site. Other examples of biodesign tasks that require similar fast exact geometric searches of potential side chain positioning include mimicking binding hotspots, design of metal binding clusters and the design of modular hydrogen binding networks for specificity. In these applications, the speed and scaling of geometric searches limits the scope of downstream design to small patterns. Here, we present an adaptive algorithm capable of searching for side chain take-off angles, which is compatible with an arbitrarily specified functional pattern and which enjoys substantive performance improvements over previous methods. We demonstrate this method in both genetically encoded (protein) and synthetic (peptidomimetic) design scenarios. Examples of using this method with the Rosetta framework for protein design are provided. Our implementation is compatible with multiple protein design frameworks and is freely available as a set of python scripts (https://github.com/JiangTian/adaptive-geometric-search-for-protein-design).
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Affiliation(s)
- Tian Jiang
- Computer ScienceDepartment, Courant Institute of Mathematical Sciences, New York University, New York, NY, USA
| | - P Douglas Renfrew
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE
- Center for Computational Biology, Flatiron Institute, Simons Foundation, New York, NY, USA
| | - Kevin Drew
- Center for Systems and Synthetic Biology, Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX, USA
| | - Noah Youngs
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Glenn L Butterfoss
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Richard Bonneau
- Computer ScienceDepartment, Courant Institute of Mathematical Sciences, New York University, New York, NY, USA
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE
- Center for Computational Biology, Flatiron Institute, Simons Foundation, New York, NY, USA
| | - Den Nis Shasha
- Computer ScienceDepartment, Courant Institute of Mathematical Sciences, New York University, New York, NY, USA
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14
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Nakashige TG, Bowman SEJ, Zygiel EM, Drennan CL, Nolan EM. Biophysical Examination of the Calcium-Modulated Nickel-Binding Properties of Human Calprotectin Reveals Conformational Change in the EF-Hand Domains and His 3Asp Site. Biochemistry 2018; 57:4155-4164. [PMID: 29890074 PMCID: PMC6050108 DOI: 10.1021/acs.biochem.8b00415] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Calprotectin (CP, S100A8/S100A9 oligomer, MRP-8/MRP-14 oligomer) is a host-defense protein that sequesters nutrient transition metals from microbes. Each S100A8/S100A9 heterodimer contains four EF-hand domains and two transition-metal-binding sites. We investigate the effect of Ca(II) ions on the structure and Ni(II)-binding properties of human CP. By employing energy dispersive X-ray (EDX) spectroscopy, we evaluate the metal content of Ni(II)-bound CP-Ser [oligomer of S100A8(C42S) and S100A9(C3S)] crystals obtained in the absence and presence of Ca(II). We present a 2.1 Å resolution crystal structure of Ni(II)-bound CP-Ser and compare this structure to a reported Ni(II)- and Ca(II)-bound CP-Ser structure [Nakashige, T. G., et al. (2017) J. Am. Chem. Soc. 139, 8828-8836]. This analysis reveals conformational changes associated with coordination of Ca(II) to the EF-hands of S100A9 and that Ca(II) binding affects the coordination number and geometry of the Ni(II) ion bound to the His3Asp site. In contrast, negligible differences are observed for the Ni(II)-His6 site in the absence and presence of Ca(II). Biochemical studies show that, whereas the His6 site has a thermodynamic preference for Ni(II) over Zn(II), the His3Asp site selects for Zn(II) over Ni(II), and relatively rapid metal exchange occurs at this site. These observations inform the working model for how CP withholds nutrient metals in the extracellular space.
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15
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IDPM: an online database for ion distribution in protein molecules. BMC Bioinformatics 2018; 19:102. [PMID: 29548284 PMCID: PMC5857119 DOI: 10.1186/s12859-018-2110-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 03/06/2018] [Indexed: 11/21/2022] Open
Abstract
Background Interactions between ions and proteins have been extensively studied, yet most of the studies focus on the ion binding site. The binding mechanism for many ion binding sites can be clearly described from high resolution structures. Although knowledge accumulated on a case-by-case basis is valuable, it is also important to study the ion-protein interaction statistically. From experimentally determined structures, it is possible to examine the ion distribution around each amino acid. Such distributions can reveal relation between ions and amino acids, so it is desirable to carry out a systematic survey of ‘ion-amino acid’ pairing interaction and share the information with a publicly available database. Results The survey in the Protein Data Bank (PDB) revealed that approximately 40% of molecules records contain at least one ion. To reduce the bias resulted from protein redundancy, the statistics were extracted from a non-redundant dataset by excluding the proteins with similar sequences. Based on the structures of protein molecules and the location of ions, the statistical distributions of ions around each proteinogenic amino acid type were investigated and further summarized in a database. To systematically quantify the interactions between ions and each amino acid, the positions of ions were mapped to the coordinate system centered at each neighboring amino acid. It was found that the distribution of ions follows the expected rules governed by the physicochemical interactions in general. Large variations were observed, reflecting the preference in ‘ion-amino acid’ interactions. The analysis program is written in the Python programming language. The statistical results and program are available from the online database: ion distribution in protein molecules (IDPM) at http://liulab.csrc.ac.cn/idpm/. Conclusion The spatial distribution of ions around amino acids is documented and analyzed. The statistics can be useful for identifying ion types for a given site in biomolecules, and can be potentially used in ion position prediction for given structures. Electronic supplementary material The online version of this article (10.1186/s12859-018-2110-9) contains supplementary material, which is available to authorized users.
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16
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Affiliation(s)
- Zhuoqin Yu
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824-1322, United States
| | - Pengfei Li
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824-1322, United States
| | - Kenneth M. Merz
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824-1322, United States
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17
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Yuan M, Vásquez-Valdivieso MG, McNae IW, Michels PAM, Fothergill-Gilmore LA, Walkinshaw MD. Structures of Leishmania Fructose-1,6-Bisphosphatase Reveal Species-Specific Differences in the Mechanism of Allosteric Inhibition. J Mol Biol 2017; 429:3075-3089. [PMID: 28882541 PMCID: PMC5639204 DOI: 10.1016/j.jmb.2017.08.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 08/14/2017] [Accepted: 08/17/2017] [Indexed: 11/29/2022]
Abstract
The gluconeogenic enzyme fructose-1,6-bisphosphatase has been proposed as a potential drug target against Leishmania parasites that cause up to 20,000-30,000 deaths annually. A comparison of three crystal structures of Leishmania major fructose-1,6-bisphosphatase (LmFBPase) along with enzyme kinetic data show how AMP acts as an allosteric inhibitor and provides insight into its metal-dependent reaction mechanism. The crystal structure of the apoenzyme form of LmFBPase is a homotetramer in which the dimer of dimers adopts a planar conformation with disordered "dynamic loops". The structure of LmFBPase, complexed with manganese and its catalytic product phosphate, shows the dynamic loops locked into the active sites. A third crystal structure of LmFBPase complexed with its allosteric inhibitor AMP shows an inactive form of the tetramer, in which the dimer pairs are rotated by 18° relative to each other. The three structures suggest an allosteric mechanism in which AMP binding triggers a rearrangement of hydrogen bonds across the large and small interfaces. Retraction of the "effector loop" required for AMP binding releases the side chain of His23 from the dimer-dimer interface. This is coupled with a flip of the side chain of Arg48 which ties down the key catalytic dynamic loop in a disengaged conformation and also locks the tetramer in an inactive rotated T-state. The structure of the effector site of LmFBPase shows different structural features compared with human FBPases, thereby offering a potential and species-specific drug target.
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Affiliation(s)
- Meng Yuan
- Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Montserrat G Vásquez-Valdivieso
- Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Iain W McNae
- Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Paul A M Michels
- Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Linda A Fothergill-Gilmore
- Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Malcolm D Walkinshaw
- Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, Max Born Crescent, Edinburgh EH9 3BF, UK.
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18
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Temtrirath K, Okumura K, Maruyama Y, Mikami B, Murata K, Hashimoto W. Binding mode of metal ions to the bacterial iron import protein EfeO. Biochem Biophys Res Commun 2017; 493:1095-1101. [PMID: 28919419 DOI: 10.1016/j.bbrc.2017.09.057] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 09/12/2017] [Indexed: 01/18/2023]
Abstract
The tripartite EfeUOB system functions as a low pH iron importer in Gram-negative bacteria. In the alginate-assimilating bacterium Sphingomonas sp. strain A1, an additional EfeO-like protein (Algp7) is encoded downstream of the efeUOB operon. Here we show the metal binding mode of Algp7, which carries a M_75 metallopeptidase motif. The Algp7 protein was purified from recombinant E. coli cells and was subsequently characterized using differential scanning fluorimetry, fluorescence spectrometry, atomic absorption spectroscopy, and X-ray crystallography. The fluorescence of a dye, SYPRO Orange, bound to denatured Algp7 in the absence and presence of metal ions was measured during heat treatment. The fluorescence profile of Algp7 in the presence of metals such as ferric, ferrous, and zinc ions, shifted to a higher temperature, suggesting that Algp7 binds these metal ions and that metal ion-bound Algp7 is more thermally stable than the ligand-free form. Algp7 was directly demonstrated to show an ability to bind copper ion by atomic absorption spectroscopy. Crystal structure of metal ion-bound Algp7 revealed that the metal ion is bound to the cleft surrounded by several acidic residues. Four residues, Glu79, Glu82, Asp96, and Glu178, distinct from the M_75 motif (His115xxGlu118), are coordinated to the metal ion. This is the first report to provide structural insights into metal binding by the bacterial EfeO element.
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Affiliation(s)
- Kanate Temtrirath
- Laboratory of Basic and Applied Molecular Biotechnology, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Kenji Okumura
- Laboratory of Basic and Applied Molecular Biotechnology, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Yukie Maruyama
- Laboratory of Food Microbiology, Department of Life Science, Faculty of Science and Engineering, Setsunan University, Neyagawa, Osaka 572-8508, Japan
| | - Bunzo Mikami
- Laboratory of Applied Structural Biology, Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Kousaku Murata
- Laboratory of Food Microbiology, Department of Life Science, Faculty of Science and Engineering, Setsunan University, Neyagawa, Osaka 572-8508, Japan
| | - Wataru Hashimoto
- Laboratory of Basic and Applied Molecular Biotechnology, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan.
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19
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Hansen WA, Khare SD. Benchmarking a computational design method for the incorporation of metal ion-binding sites at symmetric protein interfaces. Protein Sci 2017; 26:1584-1594. [PMID: 28513090 PMCID: PMC5521545 DOI: 10.1002/pro.3194] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 04/07/2017] [Accepted: 05/06/2017] [Indexed: 11/12/2022]
Abstract
The design of novel metal-ion binding sites along symmetric axes in protein oligomers could provide new avenues for metalloenzyme design, construction of protein-based nanomaterials and novel ion transport systems. Here, we describe a computational design method, symmetric protein recursive ion-cofactor sampling (SyPRIS), for locating constellations of backbone positions within oligomeric protein structures that are capable of supporting desired symmetrically coordinated metal ion(s) chelated by sidechains (chelant model). Using SyPRIS on a curated benchmark set of protein structures with symmetric metal binding sites, we found high recovery of native metal coordinating rotamers: in 65 of the 67 (97.0%) cases, native rotamers featured in the best scoring model while in the remaining cases native rotamers were found within the top three scoring models. In a second test, chelant models were crossmatched against protein structures with identical cyclic symmetry. In addition to recovering all native placements, 10.4% (8939/86013) of the non-native placements, had acceptable geometric compatibility scores. Discrimination between native and non-native metal site placements was further enhanced upon constrained energy minimization using the Rosetta energy function. Upon sequence design of the surrounding first-shell residues, we found further stabilization of native placements and a small but significant (1.7%) number of non-native placement-based sites with favorable Rosetta energies, indicating their designability in existing protein interfaces. The generality of the SyPRIS approach allows design of novel symmetric metal sites including with non-natural amino acid sidechains, and should enable the predictive incorporation of a variety of metal-containing cofactors at symmetric protein interfaces.
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Affiliation(s)
- William A. Hansen
- Institute for Quantitative Biomedicine at Rutgers610 Taylor RoadPiscatawayNew Jersey08854
- Center for integrative Proteomics Research610 Taylor RoadPiscatawayNew Jersey08854
| | - Sagar D. Khare
- Institute for Quantitative Biomedicine at Rutgers610 Taylor RoadPiscatawayNew Jersey08854
- Center for integrative Proteomics Research610 Taylor RoadPiscatawayNew Jersey08854
- Chemistry and Chemical Biology at Rutgers610 Taylor RoadPiscatawayNew Jersey08854
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20
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Hegde RP, Pavithra GC, Dey D, Almo SC, Ramakumar S, Ramagopal UA. Can the propensity of protein crystallization be increased by using systematic screening with metals? Protein Sci 2017. [PMID: 28643473 DOI: 10.1002/pro.3214] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Protein crystallization is one of the major bottlenecks in protein structure elucidation with new strategies being constantly developed to improve the chances of crystallization. Generally, well-ordered epitopes possessing complementary surface and capable of producing stable inter-protein interactions generate a regular three-dimensional arrangement of protein molecules which eventually results in a crystal lattice. Metals, when used for crystallization, with their various coordination numbers and geometries, can generate such epitopes mediating protein oligomerization and/or establish crystal contacts. Some examples of metal-mediated oligomerization and crystallization together with our experience on metal-mediated crystallization of a putative rRNA methyltransferase from Sinorhizobium meliloti are presented. Analysis of crystal structures from protein data bank (PDB) using a non-redundant data set with a 90% identity cutoff, reveals that around 67% of proteins contain at least one metal ion, with ∼14% containing combination of metal ions. Interestingly, metal containing conditions in most commercially available and popular crystallization kits generally contain only a single metal ion, with combinations of metals only in a very few conditions. Based on the results presented in this review, it appears that the crystallization screens need expansion with systematic screening of metal ions that could be crucial for stabilizing the protein structure or for establishing crystal contact and thereby aiding protein crystallization.
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Affiliation(s)
- Raghurama P Hegde
- Division of Biological Sciences, Poornaprajna Institute of Scientific Research, Bangalore, 560080, India
| | - Gowribidanur C Pavithra
- Division of Biological Sciences, Poornaprajna Institute of Scientific Research, Bangalore, 560080, India
- Manipal University, Manipal, 576104, India
| | - Debayan Dey
- Division of Biological Sciences, Poornaprajna Institute of Scientific Research, Bangalore, 560080, India
- Department of Physics, Indian Institute of Science, Bangalore, 560012, India
| | - Steven C Almo
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York, 10461
- Department of Physiology & Biophysics, Albert Einstein College of Medicine, Bronx, New York, 10461
| | - S Ramakumar
- Department of Physics, Indian Institute of Science, Bangalore, 560012, India
| | - Udupi A Ramagopal
- Division of Biological Sciences, Poornaprajna Institute of Scientific Research, Bangalore, 560080, India
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York, 10461
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21
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Yao S, Flight RM, Rouchka EC, Moseley HNB. Perspectives and expectations in structural bioinformatics of metalloproteins. Proteins 2017; 85:938-944. [PMID: 28168746 PMCID: PMC5389925 DOI: 10.1002/prot.25263] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 01/16/2017] [Accepted: 01/31/2017] [Indexed: 01/21/2023]
Abstract
Recent papers highlight the presence of large numbers of compressed angles in metal ion coordination geometries for metalloprotein entries in the worldwide Protein Data Bank, due mainly to multidentate coordination. The prevalence of these compressed angles has raised the controversial idea that significantly populated aberrant or even novel coordination geometries may exist. Some of these papers have undergone severe criticism, apparently due to views held that only canonical coordination geometries exist in significant numbers. While criticism of controversial ideas is warranted and to be expected, we believe that a line was crossed where unfair criticism was put forth to discredit an inconvenient result that compressed angles exist in large numbers, which does not support the dogmatic canonical coordination geometry view. We present a review of the major controversial results and their criticisms, pointing out both good suggestions that have been incorporated in new analyses, but also unfair criticism that was put forth to support a particular view. We also suggest that better science is enabled through: (i) a more collegial and collaborative approach in future critical reviews and (ii) the requirement for a description of methods and data including source code and visualizations that enables full reproducibility of results. Proteins 2017; 85:938-944. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Sen Yao
- School of Interdisciplinary and Graduate Studies, University of Louisville, Louisville, Kentucky, 40292
- Department of Computer Engineering and Computer Science, University of Louisville, Louisville, Kentucky, 40292
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, 40356
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, 40356
- Center for Environmental and Systems Biochemistry, University of Kentucky, Lexington, Kentucky, 40356
| | - Robert M Flight
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, 40356
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, 40356
- Center for Environmental and Systems Biochemistry, University of Kentucky, Lexington, Kentucky, 40356
| | - Eric C Rouchka
- School of Interdisciplinary and Graduate Studies, University of Louisville, Louisville, Kentucky, 40292
- Department of Computer Engineering and Computer Science, University of Louisville, Louisville, Kentucky, 40292
| | - Hunter N B Moseley
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, 40356
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, 40356
- Center for Environmental and Systems Biochemistry, University of Kentucky, Lexington, Kentucky, 40356
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22
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Computational approaches for de novo design and redesign of metal-binding sites on proteins. Biosci Rep 2017; 37:BSR20160179. [PMID: 28167677 PMCID: PMC5482196 DOI: 10.1042/bsr20160179] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 02/06/2017] [Accepted: 02/06/2017] [Indexed: 12/25/2022] Open
Abstract
Metal ions play pivotal roles in protein structure, function and stability. The functional and structural diversity of proteins in nature expanded with the incorporation of metal ions or clusters in proteins. Approximately one-third of these proteins in the databases contain metal ions. Many biological and chemical processes in nature involve metal ion-binding proteins, aka metalloproteins. Many cellular reactions that underpin life require metalloproteins. Most of the remarkable, complex chemical transformations are catalysed by metalloenzymes. Realization of the importance of metal-binding sites in a variety of cellular events led to the advancement of various computational methods for their prediction and characterization. Furthermore, as structural and functional knowledgebase about metalloproteins is expanding with advances in computational and experimental fields, the focus of the research is now shifting towards de novo design and redesign of metalloproteins to extend nature’s own diversity beyond its limits. In this review, we will focus on the computational toolbox for prediction of metal ion-binding sites, de novo metalloprotein design and redesign. We will also give examples of tailor-made artificial metalloproteins designed with the computational toolbox.
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23
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Yao S, Flight RM, Rouchka EC, Moseley HNB. Aberrant coordination geometries discovered in the most abundant metalloproteins. Proteins 2017; 85:885-907. [PMID: 28142195 PMCID: PMC5389913 DOI: 10.1002/prot.25257] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 01/16/2017] [Accepted: 01/18/2017] [Indexed: 11/09/2022]
Abstract
Metalloproteins bind and utilize metal ions for a variety of biological purposes. Due to the ubiquity of metalloprotein involvement throughout these processes across all domains of life, how proteins coordinate metal ions for different biochemical functions is of great relevance to understanding the implementation of these biological processes. Toward these ends, we have improved our methodology for structurally and functionally characterizing metal binding sites in metalloproteins. Our new ligand detection method is statistically much more robust, producing estimated false positive and false negative rates of ∼0.11% and ∼1.2%, respectively. Additional improvements expand both the range of metal ions and their coordination number that can be effectively analyzed. Also, the inclusion of additional quality control filters has significantly improved structure-function Spearman correlations as demonstrated by rho values greater than 0.90 for several metal coordination analyses and even one rho value above 0.95. Also, improvements in bond-length distributions have revealed bond-length modes specific to chemical functional groups involved in multidentation. Using these improved methods, we analyzed all single metal ion binding sites with Zn, Mg, Ca, Fe, and Na ions in the wwPDB, producing statistically rigorous results supporting the existence of both a significant number of unexpected compressed angles and subsequent aberrant metal ion coordination geometries (CGs) within structurally known metalloproteins. By recognizing these aberrant CGs in our clustering analyses, high correlations are achieved between structural and functional descriptions of metal ion coordination. Moreover, distinct biochemical functions are associated with aberrant CGs versus nonaberrant CGs. Proteins 2017; 85:885-907. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Sen Yao
- School of Interdisciplinary and Graduate Studies, University of Louisville, Louisville, Kentucky, 40292.,Department of Computer Engineering and Computer Science, University of Louisville, Louisville, Kentucky, 40292.,Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, 40356.,Markey Cancer Center, University of Kentucky, Lexington, Kentucky, 40356.,Center for Environmental and Systems Biochemistry, University of Kentucky, Lexington, Kentucky, 40356
| | - Robert M Flight
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, 40356.,Markey Cancer Center, University of Kentucky, Lexington, Kentucky, 40356.,Center for Environmental and Systems Biochemistry, University of Kentucky, Lexington, Kentucky, 40356
| | - Eric C Rouchka
- School of Interdisciplinary and Graduate Studies, University of Louisville, Louisville, Kentucky, 40292.,Department of Computer Engineering and Computer Science, University of Louisville, Louisville, Kentucky, 40292
| | - Hunter N B Moseley
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, 40356.,Markey Cancer Center, University of Kentucky, Lexington, Kentucky, 40356.,Center for Environmental and Systems Biochemistry, University of Kentucky, Lexington, Kentucky, 40356
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24
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Metal dependence and branched RNA cocrystal structures of the RNA lariat debranching enzyme Dbr1. Proc Natl Acad Sci U S A 2016; 113:14727-14732. [PMID: 27930312 DOI: 10.1073/pnas.1612729114] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Intron lariats are circular, branched RNAs (bRNAs) produced during pre-mRNA splicing. Their unusual chemical and topological properties arise from branch-point nucleotides harboring vicinal 2',5'- and 3',5'-phosphodiester linkages. The 2',5'-bonds must be hydrolyzed by the RNA debranching enzyme Dbr1 before spliced introns can be degraded or processed into small nucleolar RNA and microRNA derived from intronic RNA. Here, we measure the activity of Dbr1 from Entamoeba histolytica by using a synthetic, dark-quenched bRNA substrate that fluoresces upon hydrolysis. Purified enzyme contains nearly stoichiometric equivalents of Fe and Zn per polypeptide and demonstrates turnover rates of ∼3 s-1 Similar rates are observed when apo-Dbr1 is reconstituted with Fe(II)+Zn(II) under aerobic conditions. Under anaerobic conditions, a rate of ∼4.0 s-1 is observed when apoenzyme is reconstituted with Fe(II). In contrast, apo-Dbr1 reconstituted with Mn(II) or Fe(II) under aerobic conditions is inactive. Diffraction data from crystals of purified enzyme using X-rays tuned to the Fe absorption edge show Fe partitions primarily to the β-pocket and Zn to the α-pocket. Structures of the catalytic mutant H91A in complex with 7-mer and 16-mer synthetic bRNAs reveal bona fide RNA branchpoints in the Dbr1 active site. A bridging hydroxide is in optimal position for nucleophilic attack of the scissile phosphate. The results clarify uncertainties regarding structure/function relationships in Dbr1 enzymes, and the fluorogenic probe permits high-throughput screening for inhibitors that may hold promise as treatments for retroviral infections and neurodegenerative disease.
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25
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Minimal Functional Sites in Metalloproteins and Their Usage in Structural Bioinformatics. Int J Mol Sci 2016; 17:ijms17050671. [PMID: 27153067 PMCID: PMC4881497 DOI: 10.3390/ijms17050671] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2016] [Revised: 04/18/2016] [Accepted: 04/28/2016] [Indexed: 12/12/2022] Open
Abstract
Metal ions play a functional role in numerous biochemical processes and cellular pathways. Indeed, about 40% of all enzymes of known 3D structure require a metal ion to be able to perform catalysis. The interactions of the metals with the macromolecular framework determine their chemical properties and reactivity. The relevant interactions involve both the coordination sphere of the metal ion and the more distant interactions of the so-called second sphere, i.e., the non-bonded interactions between the macromolecule and the residues coordinating the metal (metal ligands). The metal ligands and the residues in their close spatial proximity define what we call a minimal functional site (MFS). MFSs can be automatically extracted from the 3D structures of metal-binding biological macromolecules deposited in the Protein Data Bank (PDB). They are 3D templates that describe the local environment around a metal ion or metal cofactor and do not depend on the overall macromolecular structure. MFSs provide a different view on metal-binding proteins and nucleic acids, completely focused on the metal. Here we present different protocols and tools based upon the concept of MFS to obtain deeper insight into the structural and functional properties of metal-binding macromolecules. We also show that structure conservation of MFSs in metalloproteins relates to local sequence similarity more strongly than to overall protein similarity.
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26
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Abstract
The use of macromolecular structures is widespread for a variety of applications, from teaching protein structure principles all the way to ligand optimization in drug development. Applying data mining techniques on these experimentally determined structures requires a highly uniform, standardized structural data source. The Protein Data Bank (PDB) has evolved over the years toward becoming the standard resource for macromolecular structures. However, the process selecting the data most suitable for specific applications is still very much based on personal preferences and understanding of the experimental techniques used to obtain these models. In this chapter, we will first explain the challenges with data standardization, annotation, and uniformity in the PDB entries determined by X-ray crystallography. We then discuss the specific effect that crystallographic data quality and model optimization methods have on structural models and how validation tools can be used to make informed choices. We also discuss specific advantages of using the PDB_REDO databank as a resource for structural data. Finally, we will provide guidelines on how to select the most suitable protein structure models for detailed analysis and how to select a set of structure models suitable for data mining.
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Affiliation(s)
- Bart van Beusekom
- Department of Biochemistry, Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
| | - Anastassis Perrakis
- Department of Biochemistry, Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
| | - Robbie P Joosten
- Department of Biochemistry, Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands.
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27
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Abstract
Metal ions are essential cofactors for the structure and functions of nucleic acids. Yet, the early discovery in the 70s of the crucial role of Mg(2+) in stabilizing tRNA structures has occulted for a long time the importance of monovalent cations. Renewed interest in these ions was brought in the late 90s by the discovery of specific potassium metal ions in the core of a group I intron. Their importance in nucleic acid folding and catalytic activity is now well established. However, detection of K(+) and Na(+) ions is notoriously problematic and the question about their specificity is recurrent. Here we review the different methods that can be used to detect K(+) and Na(+) ions in nucleic acid structures such as X-ray crystallography, nuclear magnetic resonance or molecular dynamics simulations. We also discuss specific versus non-specific binding to different structures through various examples.
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Affiliation(s)
- Pascal Auffinger
- Architecture et Réactivité de l'ARN, Université de Strasbourg, IBMC, CNRS, 15 rue René Descartes, F-67084, Strasbourg, France.
| | - Luigi D'Ascenzo
- Architecture et Réactivité de l'ARN, Université de Strasbourg, IBMC, CNRS, 15 rue René Descartes, F-67084, Strasbourg, France.
| | - Eric Ennifar
- Architecture et Réactivité de l'ARN, Université de Strasbourg, IBMC, CNRS, 15 rue René Descartes, F-67084, Strasbourg, France.
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28
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De Santis E, Minicozzi V, Proux O, Rossi G, Silva KI, Lawless MJ, Stellato F, Saxena S, Morante S. Cu(II)-Zn(II) Cross-Modulation in Amyloid-Beta Peptide Binding: An X-ray Absorption Spectroscopy Study. J Phys Chem B 2015; 119:15813-20. [PMID: 26646533 DOI: 10.1021/acs.jpcb.5b10264] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this work we analyze at a structural level the mechanism by which Cu(II) and Zn(II) ions compete for binding to the Aβ peptides that is involved in the etiology of Alzheimer's disease. We collected X-ray absorption spectroscopy data on samples containing Aβ with Cu and Zn at different concentration ratios. We show that the order in which metals are added to the peptide solution matters and that, when Zn is added first, it prevents Cu from binding. On the contrary, when Cu is added first, it does not (completely) prevent Zn binding to Aβ peptides. Our analysis suggests that Cu and Zn ions are coordinated to different numbers of histidine residues depending on the [ion]:[peptide] concentration ratio.
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Affiliation(s)
- Emiliano De Santis
- Department of Physics and INFN, University of Rome , Tor Vergata, Rome 00133, Italy
| | - Velia Minicozzi
- Department of Physics and INFN, University of Rome , Tor Vergata, Rome 00133, Italy
| | - Olivier Proux
- Observatoire des Sciences de l'Univers de Grenoble , Grenoble 38400, France
| | - Giancarlo Rossi
- Department of Physics and INFN, University of Rome , Tor Vergata, Rome 00133, Italy.,Centro Fermi , Rome 00184, Italy
| | - K Ishara Silva
- Department of Chemistry, University of Pittsburgh , Pittsburgh, Pennsylvania 15260, United States
| | - Matthew J Lawless
- Department of Chemistry, University of Pittsburgh , Pittsburgh, Pennsylvania 15260, United States
| | - Francesco Stellato
- Department of Physics and INFN, University of Rome , Tor Vergata, Rome 00133, Italy
| | - Sunil Saxena
- Department of Chemistry, University of Pittsburgh , Pittsburgh, Pennsylvania 15260, United States
| | - Silvia Morante
- Department of Physics and INFN, University of Rome , Tor Vergata, Rome 00133, Italy
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29
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Pérez-Villa A, Darvas M, Bussi G. ATP dependent NS3 helicase interaction with RNA: insights from molecular simulations. Nucleic Acids Res 2015; 43:8725-34. [PMID: 26358809 PMCID: PMC4605317 DOI: 10.1093/nar/gkv872] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 08/18/2015] [Indexed: 01/05/2023] Open
Abstract
Non-structural protein 3 (NS3) helicase from hepatitis C virus is an enzyme that unwinds and translocates along nucleic acids with an ATP-dependent mechanism and has a key role in the replication of the viral RNA. An inchworm-like mechanism for translocation has been proposed based on crystal structures and single molecule experiments. We here perform atomistic molecular dynamics in explicit solvent on the microsecond time scale of the available experimental structures. We also construct and simulate putative intermediates for the translocation process, and we perform non-equilibrium targeted simulations to estimate their relative stability. For each of the simulated structures we carefully characterize the available conformational space, the ligand binding pocket, and the RNA binding cleft. The analysis of the hydrogen bond network and of the non-equilibrium trajectories indicates an ATP-dependent stabilization of one of the protein conformers. Additionally, enthalpy calculations suggest that entropic effects might be crucial for the stabilization of the experimentally observed structures.
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Affiliation(s)
- Andrea Pérez-Villa
- Scuola Internazionale Superiore di Studi Avanzati, International School for Advanced Studies, 265, Via Bonomea, I-34136 Trieste, Italy
| | - Maria Darvas
- Scuola Internazionale Superiore di Studi Avanzati, International School for Advanced Studies, 265, Via Bonomea, I-34136 Trieste, Italy
| | - Giovanni Bussi
- Scuola Internazionale Superiore di Studi Avanzati, International School for Advanced Studies, 265, Via Bonomea, I-34136 Trieste, Italy
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30
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Buth SA, Menin L, Shneider MM, Engel J, Boudko SP, Leiman PG. Structure and Biophysical Properties of a Triple-Stranded Beta-Helix Comprising the Central Spike of Bacteriophage T4. Viruses 2015; 7:4676-706. [PMID: 26295253 PMCID: PMC4576200 DOI: 10.3390/v7082839] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 08/10/2015] [Accepted: 08/13/2015] [Indexed: 12/22/2022] Open
Abstract
Gene product 5 (gp5) of bacteriophage T4 is a spike-shaped protein that functions to disrupt the membrane of the target cell during phage infection. Its C-terminal domain is a long and slender β-helix that is formed by three polypeptide chains wrapped around a common symmetry axis akin to three interdigitated corkscrews. The folding and biophysical properties of such triple-stranded β-helices, which are topologically related to amyloid fibers, represent an unsolved biophysical problem. Here, we report structural and biophysical characterization of T4 gp5 β-helix and its truncated mutants of different lengths. A soluble fragment that forms a dimer of trimers and that could comprise a minimal self-folding unit has been identified. Surprisingly, the hydrophobic core of the β-helix is small. It is located near the C-terminal end of the β-helix and contains a centrally positioned and hydrated magnesium ion. A large part of the β-helix interior comprises a large elongated cavity that binds palmitic, stearic, and oleic acids in an extended conformation suggesting that these molecules might participate in the folding of the complete β-helix.
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Affiliation(s)
- Sergey A Buth
- Institute of Physics of Biological Systems, École Polytechnique Fédérale de Lausanne (EPFL), BSP 415, 1015 Lausanne, Switzerland.
| | - Laure Menin
- Service de Spectrométrie de Masse, ISIC, EPFL, BCH 1520, 1015 Lausanne, Switzerland.
| | - Mikhail M Shneider
- Institute of Physics of Biological Systems, École Polytechnique Fédérale de Lausanne (EPFL), BSP 415, 1015 Lausanne, Switzerland.
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Laboratory of Molecular Bioengineering, 16/10 Miklukho-Maklaya St., 117997 Moscow, Russia.
| | - Jürgen Engel
- Department of Biophysical Chemistry, Biozentrum, University of Basel, Klingelbergstrasse 70, CH-4056 Basel, Switzerland.
| | - Sergei P Boudko
- Department of Biophysical Chemistry, Biozentrum, University of Basel, Klingelbergstrasse 70, CH-4056 Basel, Switzerland.
- Department of Biological Sciences, Purdue University, 915 W. State Street, West Lafayette, IN 47907-2054, USA.
- The Research Department, Shriner's Hospital for Children, 3101 Sam Jackson Park Road, Portland, OR 97239, USA.
- Department of Biochemistry and Molecular Biology, Oregon Health and Science University, 3181 Sam Jackson Park Road, Portland, OR 97239, USA.
| | - Petr G Leiman
- Institute of Physics of Biological Systems, École Polytechnique Fédérale de Lausanne (EPFL), BSP 415, 1015 Lausanne, Switzerland.
- Department of Biological Sciences, Purdue University, 915 W. State Street, West Lafayette, IN 47907-2054, USA.
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31
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Pedebos C, Arantes PR, Giesel GM, Verli H. In silicoInvestigation of the PglB Active Site Reveals Transient Catalytic States and Octahedral Metal Ion Coordination. Glycobiology 2015. [DOI: 10.1093/glycob/cwv053] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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32
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Ligabue-Braun R, Sachett LG, Pol-Fachin L, Verli H. The Calcium Goes Meow: Effects of Ions and Glycosylation on Fel d 1, the Major Cat Allergen. PLoS One 2015; 10:e0132311. [PMID: 26134118 PMCID: PMC4489793 DOI: 10.1371/journal.pone.0132311] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2015] [Accepted: 06/11/2015] [Indexed: 12/20/2022] Open
Abstract
The major cat allergen, Fel d 1, is a structurally complex protein with two N-glycosylation sites that may be filled by different glycoforms. In addition, the protein contains three putative Ca2+ binding sites. Since the impact of these Fel d 1 structure modifications on the protein dynamics, physiology and pathology are not well established, the present work employed computational biology techniques to tackle these issues. While conformational effects brought upon by glycosylation were identified, potentially involved in cavity volume regulation, our results indicate that only the central Ca2+ ion remains coordinated to Fel d 1 in biological solutions, impairing its proposed role in modulating phospholipase A2 activity. As these results increase our understanding of Fel d 1 structural biology, they may offer new support for understanding its physiological role and impact into cat-promoted allergy.
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Affiliation(s)
- Rodrigo Ligabue-Braun
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
| | - Liana Guimarães Sachett
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
| | - Laércio Pol-Fachin
- Departamento de Química Fundamental, Universidade Federal de Pernambuco, Recife, PE, Brazil
| | - Hugo Verli
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
- * E-mail:
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Mooers BHM. Fusion RNAs in crystallographic studies of double-stranded RNA from trypanosome RNA editing. Methods Mol Biol 2015; 1240:191-216. [PMID: 25352146 DOI: 10.1007/978-1-4939-1896-6_14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Head-to-head fusions of two identical double-stranded fragments of RNA can be designed to self-assemble from a single RNA species and form a double-stranded helix with a twofold rotation axis relating the two strands. These symmetrical RNA molecules are more likely to crystallize without end-on-end statistical packing disorder because the two halves of the molecule are identical. This approach can be used to study many fragments of double-stranded RNA or many isolated helical domains from large single-stranded RNAs that may not yet be amenable to high-resolution studies by crystallography or NMR. We used fusion RNAs to study one (the U-helix) of three functional domains formed when guide RNA binds to its cognate pre-edited mRNA from the trypanosome RNA editing system. The U-helix forms when the 3' oligo(U) tail of the guide RNA (gRNA) binds to the purine-rich, pre-edited mRNA upstream from the current RNA editing site. Fusion RNAs 16-and 32-base pairs in length formed crystals that gave diffraction to 1.37 and 1.05 Å respectively. We provide the composition of a fusion RNA crystallization screen and describe the X-ray data collection, structure determination, and refinement of the crystal structures of fusion RNAs.
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Affiliation(s)
- Blaine H M Mooers
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, 975 NE 10th St., Stanton L. Young Biomedical Research Center Rm. 466, Oklahoma City, OK, 73104-5419, USA,
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34
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Gutten O, Rulíšek L. How simple is too simple? Computational perspective on importance of second-shell environment for metal-ion selectivity. Phys Chem Chem Phys 2015; 17:14393-404. [PMID: 25785686 DOI: 10.1039/c4cp04876h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The metal-ion selectivity in biomolecules represents one of the most important phenomena in bioinorganic chemistry. The open question to what extent is the selectivity in the complex bioinorganic structures such as metallopeptides determined by the first-shell ligands of the metal ion is answered herein using six model peptides complexed with the set of divalent metal ions (Mn(2+), Fe(2+), Co(2+), Ni(2+), Cu(2+), Zn(2+), Cd(2+), and Hg(2+)) and their various first-shell representations. By calculating the differences among the free energies of complexation of metal ions in these peptides and their model (truncated) systems it is quantitatively shown that the definition of the first shell is paramount to this discussion and revolves around the chemical nature of the binding site. Despite the vast conceivable diversity of peptidic structures, that suggest certain fluidity of this definition, major contributing factors are identified and assessed based on their importance for capturing metal-ion selectivity. These factors include soft/hard character of ligands and various non-covalent interactions in the vicinity of the binding site. The relative importance of these factors is considered and specific suggestions for effective construction of the models are made. The relationship of first-shell models and their corresponding parent peptides is discussed thoroughly, both with respect to their chemical similarity and potential disparity introduced by generally "non-alignable" conformational flexibility of the two systems. It is concluded that, in special cases, this disparity can be negligible and that heeding the chemical factors contributing to selectivity during construction of the model can successfully result in models that retain the affinity profile for various metal ions with high fidelity.
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Affiliation(s)
- Ondrej Gutten
- Institute of Organic Chemistry and Biochemistry, Gilead Sciences Research Center & IOCB, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Praha 6, Czech Republic.
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35
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Weichenberger CX, Afonine PV, Kantardjieff K, Rupp B. The solvent component of macromolecular crystals. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2015; 71:1023-38. [PMID: 25945568 PMCID: PMC4427195 DOI: 10.1107/s1399004715006045] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 03/25/2015] [Indexed: 11/10/2022]
Abstract
The mother liquor from which a biomolecular crystal is grown will contain water, buffer molecules, native ligands and cofactors, crystallization precipitants and additives, various metal ions, and often small-molecule ligands or inhibitors. On average, about half the volume of a biomolecular crystal consists of this mother liquor, whose components form the disordered bulk solvent. Its scattering contributions can be exploited in initial phasing and must be included in crystal structure refinement as a bulk-solvent model. Concomitantly, distinct electron density originating from ordered solvent components must be correctly identified and represented as part of the atomic crystal structure model. Herein, are reviewed (i) probabilistic bulk-solvent content estimates, (ii) the use of bulk-solvent density modification in phase improvement, (iii) bulk-solvent models and refinement of bulk-solvent contributions and (iv) modelling and validation of ordered solvent constituents. A brief summary is provided of current tools for bulk-solvent analysis and refinement, as well as of modelling, refinement and analysis of ordered solvent components, including small-molecule ligands.
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Affiliation(s)
- Christian X. Weichenberger
- Center for Biomedicine, European Academy of Bozen/Bolzano (EURAC), Viale Druso 1, Bozen/Bolzano, I-39100 Südtirol/Alto Adige, Italy
| | - Pavel V. Afonine
- Physical Biosciences Division, Lawrence Berkeley National Laboratory (LBNL), 1 Cyclotron Road, Mail Stop 64R0121, Berkeley, CA 94720, USA
| | - Katherine Kantardjieff
- College of Science and Mathematics, California State University, San Marcos, CA 92078, USA
| | - Bernhard Rupp
- Department of Forensic Crystallography, k.-k. Hofkristallamt, 991 Audrey Place, Vista, CA 92084, USA
- Department of Genetic Epidemiology, Medical University of Innsbruck, Schöpfstrasse 41, A-6020 Innsbruck, Austria
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36
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Takagi E, Hatada Y, Akita M, Ohta Y, Yokoi G, Miyazaki T, Nishikawa A, Tonozuka T. Crystal structure of the catalytic domain of a GH16 β-agarase from a deep-sea bacterium, Microbulbifer thermotolerans JAMB-A94. Biosci Biotechnol Biochem 2015; 79:625-32. [DOI: 10.1080/09168451.2014.988680] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Abstract
A deep-sea bacterium, Microbulbifer thermotolerans JAMB-A94, has a β-agarase (MtAgaA) belonging to the glycoside hydrolase family (GH) 16. The optimal temperature of this bacterium for growth is 43–49 °C, and MtAgaA is stable at 60 °C, which is one of the most thermostable enzymes among GH16 β-agarases. Here, we determined the catalytic domain structure of MtAgaA. MtAgaA consists of a β-jelly roll fold, as observed in other GH16 enzymes. The structure of MtAgaA was most similar to two β-agarases from Zobellia galactanivorans, ZgAgaA, and ZgAgaB. Although the catalytic cleft structure of MtAgaA was similar to ZgAgaA and ZgAgaB, residues at subsite −4 of MtAgaA were not conserved between them. Also, an α-helix, designated as α4′, was uniquely located near the catalytic cleft of MtAgaA. A comparison of the structures of the three enzymes suggested that multiple factors, including increased numbers of arginine and proline residues, could contribute to the thermostability of MtAgaA.
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Affiliation(s)
- Emiko Takagi
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan
- Graduate School of Nanobioscience, Yokohama City University, Yokohama, Japan
| | - Yuji Hatada
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan
- Graduate School of Nanobioscience, Yokohama City University, Yokohama, Japan
| | - Masatake Akita
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan
| | - Yukari Ohta
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan
| | - Gaku Yokoi
- Department of Applied Biological Science, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Takatsugu Miyazaki
- Department of Applied Biological Science, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Atsushi Nishikawa
- Department of Applied Biological Science, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Takashi Tonozuka
- Department of Applied Biological Science, Tokyo University of Agriculture and Technology, Tokyo, Japan
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37
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Zheng H, Shabalin IG, Handing KB, Bujnicki JM, Minor W. Magnesium-binding architectures in RNA crystal structures: validation, binding preferences, classification and motif detection. Nucleic Acids Res 2015; 43:3789-801. [PMID: 25800744 PMCID: PMC4402538 DOI: 10.1093/nar/gkv225] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 03/04/2015] [Indexed: 12/25/2022] Open
Abstract
The ubiquitous presence of magnesium ions in RNA has long been recognized as a key factor governing RNA folding, and is crucial for many diverse functions of RNA molecules. In this work, Mg(2+)-binding architectures in RNA were systematically studied using a database of RNA crystal structures from the Protein Data Bank (PDB). Due to the abundance of poorly modeled or incorrectly identified Mg(2+) ions, the set of all sites was comprehensively validated and filtered to identify a benchmark dataset of 15 334 'reliable' RNA-bound Mg(2+) sites. The normalized frequencies by which specific RNA atoms coordinate Mg(2+) were derived for both the inner and outer coordination spheres. A hierarchical classification system of Mg(2+) sites in RNA structures was designed and applied to the benchmark dataset, yielding a set of 41 types of inner-sphere and 95 types of outer-sphere coordinating patterns. This classification system has also been applied to describe six previously reported Mg(2+)-binding motifs and detect them in new RNA structures. Investigation of the most populous site types resulted in the identification of seven novel Mg(2+)-binding motifs, and all RNA structures in the PDB were screened for the presence of these motifs.
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Affiliation(s)
- Heping Zheng
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908-0736, USA Center for Structural Genomics of Infectious Diseases (CSGID) Consortium, USA Midwest Center for Structural Genomics (MCSG) Consortium, USA New York Structural Genomics Research Consortium (NYSGRC), USA
| | - Ivan G Shabalin
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908-0736, USA Center for Structural Genomics of Infectious Diseases (CSGID) Consortium, USA Midwest Center for Structural Genomics (MCSG) Consortium, USA New York Structural Genomics Research Consortium (NYSGRC), USA Enzyme Function Initiative (EFI), USA
| | - Katarzyna B Handing
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908-0736, USA Midwest Center for Structural Genomics (MCSG) Consortium, USA New York Structural Genomics Research Consortium (NYSGRC), USA Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw 02-109, Poland
| | - Janusz M Bujnicki
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw 02-109, Poland Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznan, Poland
| | - Wladek Minor
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908-0736, USA Center for Structural Genomics of Infectious Diseases (CSGID) Consortium, USA Midwest Center for Structural Genomics (MCSG) Consortium, USA New York Structural Genomics Research Consortium (NYSGRC), USA Enzyme Function Initiative (EFI), USA
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38
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Kawamura T, Kobayashi T, Watanabe N. Analysis of the HindIII-catalyzed reaction by time-resolved crystallography. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2015; 71:256-65. [PMID: 25664735 PMCID: PMC4321485 DOI: 10.1107/s1399004714025188] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 11/17/2014] [Indexed: 11/30/2022]
Abstract
In order to investigate the mechanism of the reaction catalyzed by HindIII, structures of HindIII-DNA complexes with varying durations of soaking time in cryoprotectant buffer containing manganese ions were determined by the freeze-trap method. In the crystal structures of the complexes obtained after soaking for a longer duration, two manganese ions, indicated by relatively higher electron density, are clearly observed at the two metal ion-binding sites in the active site of HindIII. The increase in the electron density of the two metal-ion peaks followed distinct pathways with increasing soaking times, suggesting variation in the binding rate constant for the two metal sites. DNA cleavage is observed when the second manganese ion appears, suggesting that HindIII uses the two-metal-ion mechanism, or alternatively that its reactivity is enhanced by the binding of the second metal ion. In addition, conformational change in a loop near the active site accompanies the catalytic reaction.
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Affiliation(s)
- Takashi Kawamura
- Synchrotron Radiation Research Center, Nagoya University, Chikusa-ku, Nagoya 464-8603, Japan
| | - Tomoki Kobayashi
- Graduate School of Engineering, Nagoya University, Chikusa-ku, Nagoya 464-8603, Japan
| | - Nobuhisa Watanabe
- Synchrotron Radiation Research Center, Nagoya University, Chikusa-ku, Nagoya 464-8603, Japan
- Graduate School of Engineering, Nagoya University, Chikusa-ku, Nagoya 464-8603, Japan
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Kaminsky W, Stenkamp RE, Skubatz H. Crystal and molecular structure of the analgesic tetrapeptide, L-Phe-L-Leu-L-Pro-L-Ser. Biopolymers 2015; 104:84-90. [PMID: 25581776 DOI: 10.1002/bip.22606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 12/09/2014] [Accepted: 12/21/2014] [Indexed: 11/06/2022]
Abstract
The tetrapeptide, L-Phe-L-Leu-L-Pro-L-Ser (FLPS), alleviates pain in a rat model of post-surgery pain. The crystal structure of the tetrapeptide is solved at high resolution (0.54 Å). The asymmetric unit contains two FLPS molecules, one Zn ion, and four molecules of water with a formula of [Zn(C23H33N4O6)2(H2O)4]. Each Zn ion is octahedrally coordinated with Phe and Ser residues from four peptide molecules [2N+4O]. The linking of Phe and Ser residues of one FLPS molecule to three other FLPS molecules by Zn ion forms a complex consisting of chains of metal ions and FLPS molecules oriented along the b axis. Analysis of molecular packing reveals the coexistence of two FLPS conformers in the same crystal. The crystallographic parameters for [Zn(C23H33N4O6)2(H2O)4] are as follows: space group P21 21 21 , a = 9.8698(2) Å, α = 90°, b = 20.1844(4) Å, β = 90°, c = 25.9302(6) Å, γ = 90°. Volume = 5165.71(19) Å(3), Z = 4, density (calc) = 1.364 Mg/cm(3), and agreement factor R1 = 4.13%.
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Affiliation(s)
- Werner Kaminsky
- Department of Chemistry, University of Washington, Seattle, WA, 98195
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40
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Abstract
From the catalytic reactions that sustain the global oxygen, nitrogen, and carbon cycles to the stabilization of DNA processing proteins, transition metal ions and metallocofactors play key roles in biology. Although the exquisite interplay between metal ions and protein scaffolds has been studied extensively, the fact that the biological roles of the metals often stem from their placement in the interfaces between proteins and protein subunits is not always recognized. Interfacial metal ions stabilize permanent or transient protein-protein interactions, enable protein complexes involved in cellular signaling to adopt distinct conformations in response to environmental stimuli, and catalyze challenging chemical reactions that are uniquely performed by multisubunit protein complexes. This review provides a structural survey of transition metal ions and metallocofactors found in protein-protein interfaces, along with a series of selected examples that illustrate their diverse biological utility and significance.
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Affiliation(s)
- Woon Ju Song
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093; emails: , ,
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41
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Structural and mechanistic studies of polymerase η bypass of phenanthriplatin DNA damage. Proc Natl Acad Sci U S A 2014; 111:9133-8. [PMID: 24927576 DOI: 10.1073/pnas.1405739111] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Platinum drugs are a mainstay of anticancer chemotherapy. Nevertheless, tumors often display inherent or acquired resistance to platinum-based treatments, prompting the search for new compounds that do not exhibit cross-resistance with current therapies. Phenanthriplatin, cis-diamminephenanthridinechloroplatinum(II), is a potent monofunctional platinum complex that displays a spectrum of activity distinct from those of the clinically approved platinum drugs. Inhibition of RNA polymerases by phenanthriplatin lesions has been implicated in its mechanism of action. The present study evaluates the ability of phenanthriplatin lesions to inhibit DNA replication, a function disrupted by traditional platinum drugs. Phenanthriplatin lesions effectively inhibit DNA polymerases ν, ζ, and κ and the Klenow fragment. In contrast to results obtained with DNA damaged by cisplatin, all of these polymerases were capable of inserting a base opposite a phenanthriplatin lesion, but only Pol η, an enzyme efficient in translesion synthesis, was able to fully bypass the adduct, albeit with low efficiency. X-ray structural characterization of Pol η complexed with site-specifically platinated DNA at both the insertion and +1 extension steps reveals that phenanthriplatin on DNA interacts with and inhibits Pol η in a manner distinct from that of cisplatin-DNA adducts. Unlike cisplatin and oxaliplatin, the efficacies of which are influenced by Pol η expression, phenanthriplatin is highly toxic to both Pol η+ and Pol η- cells. Given that increased expression of Pol η is a known mechanism by which cells resist cisplatin treatment, phenanthriplatin may be valuable in the treatment of cancers that are, or can easily become, resistant to cisplatin.
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42
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Analyses of cobalt-ligand and potassium-ligand bond lengths in metalloproteins: trends and patterns. J Mol Model 2014; 20:2271. [PMID: 24850495 DOI: 10.1007/s00894-014-2271-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 04/23/2014] [Indexed: 10/25/2022]
Abstract
Cobalt and potassium are biologically important metal elements that are present in a large array of proteins. Cobalt is mostly found in vivo associated with a corrin ring, which represents the core of the vitamin B12 molecule. Potassium is the most abundant metal in the cytosol, and it plays a crucial role in maintaining membrane potential as well as correct protein function. Here, we report a thorough analysis of the geometric properties of cobalt and potassium coordination spheres that was performed with high resolution on a representative set of structures from the Protein Data Bank and complemented by quantum mechanical calculations realized at the DFT level of theory (B3LYP/ SDD) on mononuclear model systems. The results allowed us to draw interesting conclusions on the structural characteristics of both Co and K centers, and to evaluate the importance of effects such as their association energies and intrinsic thermodynamic stabilities. Overall, the results obtained provide useful data for enhancing the atomic models normally applied in theoretical and computational studies of Co or K proteins performed at the quantum mechanical level, and for developing molecular mechanical parameters for treating Co or K coordination spheres in molecular mechanics or molecular dynamics studies.
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43
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Valasatava Y, Rosato A, Cavallaro G, Andreini C. MetalS(3), a database-mining tool for the identification of structurally similar metal sites. J Biol Inorg Chem 2014; 19:937-45. [PMID: 24699831 DOI: 10.1007/s00775-014-1128-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 03/19/2014] [Indexed: 12/14/2022]
Abstract
We have developed a database search tool to identify metal sites having structural similarity to a query metal site structure within the MetalPDB database of minimal functional sites (MFSs) contained in metal-binding biological macromolecules. MFSs describe the local environment around the metal(s) independently of the larger context of the macromolecular structure. Such a local environment has a determinant role in tuning the chemical reactivity of the metal, ultimately contributing to the functional properties of the whole system. The database search tool, which we called MetalS(3) (Metal Sites Similarity Search), can be accessed through a Web interface at http://metalweb.cerm.unifi.it/tools/metals3/ . MetalS(3) uses a suitably adapted version of an algorithm that we previously developed to systematically compare the structure of the query metal site with each MFS in MetalPDB. For each MFS, the best superposition is kept. All these superpositions are then ranked according to the MetalS(3) scoring function and are presented to the user in tabular form. The user can interact with the output Web page to visualize the structural alignment or the sequence alignment derived from it. Options to filter the results are available. Test calculations show that the MetalS(3) output correlates well with expectations from protein homology considerations. Furthermore, we describe some usage scenarios that highlight the usefulness of MetalS(3) to obtain mechanistic and functional hints regardless of homology.
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Affiliation(s)
- Yana Valasatava
- Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Italy
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Joldybayeva B, Prorok P, Grin IR, Zharkov DO, Ishenko AA, Tudek B, Bissenbaev AK, Saparbaev M. Cloning and characterization of a wheat homologue of apurinic/apyrimidinic endonuclease Ape1L. PLoS One 2014; 9:e92963. [PMID: 24667595 PMCID: PMC3965494 DOI: 10.1371/journal.pone.0092963] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 02/27/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Apurinic/apyrimidinic (AP) endonucleases are key DNA repair enzymes involved in the base excision repair (BER) pathway. In BER, an AP endonuclease cleaves DNA at AP sites and 3'-blocking moieties generated by DNA glycosylases and/or oxidative damage. A Triticum aestivum cDNA encoding for a putative homologue of ExoIII family AP endonucleases which includes E. coli Xth, human APE1 and Arabidopsis thaliana AtApe1L has been isolated and its protein product purified and characterized. METHODOLOGY/PRINCIPAL FINDINGS We report that the putative wheat AP endonuclease, referred here as TaApe1L, contains AP endonuclease, 3'-repair phosphodiesterase, 3'-phosphatase and 3' → 5' exonuclease activities. Surprisingly, in contrast to bacterial and human AP endonucleases, addition of Mg(2+) and Ca(2+) (5-10 mM) to the reaction mixture inhibited TaApe1L whereas the presence of Mn(2+), Co(2+) and Fe(2+) cations (0.1-1.0 mM) strongly stimulated all its DNA repair activities. Optimization of the reaction conditions revealed that the wheat enzyme requires low divalent cation concentration (0.1 mM), mildly acidic pH (6-7), low ionic strength (20 mM KCl) and has a temperature optimum at around 20 °C. The steady-state kinetic parameters of enzymatic reactions indicate that TaApe1L removes 3'-blocking sugar-phosphate and 3'-phosphate groups with good efficiency (kcat/KM = 630 and 485 μM(-1) · min(-1), respectively) but possesses a very weak AP endonuclease activity as compared to the human homologue, APE1. CONCLUSIONS/SIGNIFICANCE Taken together, these data establish the DNA substrate specificity of the wheat AP endonuclease and suggest its possible role in the repair of DNA damage generated by endogenous and environmental factors.
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Affiliation(s)
- Botagoz Joldybayeva
- Department of Molecular Biology and Genetics, Faculty of Biology, al-Farabi Kazakh National University, Almaty, Kazakhstan
| | - Paulina Prorok
- Groupe «Réparation de l'ADN», CNRS UMR8200, Université Paris-Sud, Institut Gustave Roussy, Villejuif, France
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Inga R. Grin
- Groupe «Réparation de l'ADN», CNRS UMR8200, Université Paris-Sud, Institut Gustave Roussy, Villejuif, France
- SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
- Novosibirsk State University, Novosibirsk, Russia
| | - Dmitry O. Zharkov
- SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
- Novosibirsk State University, Novosibirsk, Russia
| | - Alexander A. Ishenko
- Groupe «Réparation de l'ADN», CNRS UMR8200, Université Paris-Sud, Institut Gustave Roussy, Villejuif, France
| | - Barbara Tudek
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
- Institute of Genetics and Biotechnology, University of Warsaw, Warsaw, Poland
| | - Amangeldy K. Bissenbaev
- Department of Molecular Biology and Genetics, Faculty of Biology, al-Farabi Kazakh National University, Almaty, Kazakhstan
- * E-mail: (MS); (AKB)
| | - Murat Saparbaev
- Groupe «Réparation de l'ADN», CNRS UMR8200, Université Paris-Sud, Institut Gustave Roussy, Villejuif, France
- * E-mail: (MS); (AKB)
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Baez M, Cabrera R, Pereira HM, Blanco A, Villalobos P, Ramírez-Sarmiento CA, Caniuguir A, Guixé V, Garratt RC, Babul J. A ribokinase family conserved monovalent cation binding site enhances the MgATP-induced inhibition in E. coli phosphofructokinase-2. Biophys J 2014; 105:185-93. [PMID: 23823238 DOI: 10.1016/j.bpj.2013.05.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 04/30/2013] [Accepted: 05/07/2013] [Indexed: 11/19/2022] Open
Abstract
The presence of a regulatory site for monovalent cations that affects the conformation of the MgATP-binding pocket leading to enzyme activation has been demonstrated for ribokinases. This site is selective toward the ionic radius of the monovalent cation, accepting those larger than Na(+). Phosphofructokinase-2 (Pfk-2) from Escherichia coli is homologous to ribokinase, but unlike other ribokinase family members, presents an additional site for the nucleotide that negatively regulates its enzymatic activity. In this work, we show the effect of monovalent cations on the kinetic parameters of Pfk-2 together with its three-dimensional structure determined by x-ray diffraction in the presence of K(+) or Cs(+). Kinetic characterization of the enzyme shows that K(+) and Na(+) alter neither the kcat nor the KM values for fructose-6-P or MgATP. However, the presence of K(+) (but not Na(+)) enhances the allosteric inhibition induced by MgATP. Moreover, binding experiments show that K(+) (but not Na(+)) increases the affinity of MgATP in a saturable fashion. In agreement with the biochemical data, the crystal structure of Pfk-2 obtained in the presence of MgATP shows a cation-binding site at the conserved position predicted for the ribokinase family of proteins. This site is adjacent to the MgATP allosteric binding site and is only observed in the presence of Cs(+) or K(+). These results indicate that binding of the monovalent metal ions indirectly influences the allosteric site of Pfk-2 by increasing its affinity for MgATP with no alteration in the conformation of residues present at the catalytic site.
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Affiliation(s)
- Mauricio Baez
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
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Abstract
Modeling and analogy are commonly used to identify the part that a metal may play in the structure or function of a new protein which has been recognized by structural genomics. Mespeus ( http://mespeus.bch.ed.ac.uk/MESPEUS_10/) lists metal protein interactions whose geometry has been experimentally determined and allows them to be visualized. This can contribute to the modeling process. The use of Mespeus is described with a series of examples.
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Validation of metal-binding sites in macromolecular structures with the CheckMyMetal web server. Nat Protoc 2013; 9:156-70. [PMID: 24356774 DOI: 10.1038/nprot.2013.172] [Citation(s) in RCA: 227] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Metals have vital roles in both the mechanism and architecture of biological macromolecules. Yet structures of metal-containing macromolecules in which metals are misidentified and/or suboptimally modeled are abundant in the Protein Data Bank (PDB). This shows the need for a diagnostic tool to identify and correct such modeling problems with metal-binding environments. The CheckMyMetal (CMM) web server (http://csgid.org/csgid/metal_sites/) is a sophisticated, user-friendly web-based method to evaluate metal-binding sites in macromolecular structures using parameters derived from 7,350 metal-binding sites observed in a benchmark data set of 2,304 high-resolution crystal structures. The protocol outlines how the CMM server can be used to detect geometric and other irregularities in the structures of metal-binding sites, as well as how it can alert researchers to potential errors in metal assignment. The protocol also gives practical guidelines for correcting problematic sites by modifying the metal-binding environment and/or redefining metal identity in the PDB file. Several examples where this has led to meaningful results are described in the ANTICIPATED RESULTS section. CMM was designed for a broad audience--biomedical researchers studying metal-containing proteins and nucleic acids--but it is equally well suited for structural biologists validating new structures during modeling or refinement. The CMM server takes the coordinates of a metal-containing macromolecule structure in the PDB format as input and responds within a few seconds for a typical protein structure with 2-5 metal sites and a few hundred amino acids.
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Schormann N, Banerjee S, Ricciardi R, Chattopadhyay D. Structure of the uracil complex of Vaccinia virus uracil DNA glycosylase. Acta Crystallogr Sect F Struct Biol Cryst Commun 2013; 69:1328-34. [PMID: 24316823 PMCID: PMC3855713 DOI: 10.1107/s1744309113030613] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 11/07/2013] [Indexed: 11/23/2022]
Abstract
Poxvirus uracil DNA glycosylases are the most diverse members of the family I uracil DNA glycosylases (UNGs). The crystal structure of the uracil complex of Vaccinia virus uracil DNA glycosylase (D4) was determined at 2.03 Å resolution. One uracil molecule was located in the active-site pocket in each of the 12 noncrystallographic symmetry-related D4 subunits. Although the UNGs of the poxviruses (including D4) feature significant differences in the characteristic motifs designated for uracil recognition and in the base-excision mechanism, the architecture of the active-site pocket in D4 is very similar to that in UNGs of other organisms. Overall, the interactions of the bound uracil with the active-site residues are also similar to the interactions previously observed in the structures of human and Escherichia coli UNG.
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Affiliation(s)
- N. Schormann
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - S. Banerjee
- Northeastern Collaborative Access Team and Department of Chemistry and Chemical Biology, Cornell University, Argonne, IL 60439, USA
| | - R. Ricciardi
- Department of Microbiology, School of Dental Medicine, Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - D. Chattopadhyay
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Andreini C, Cavallaro G, Rosato A, Valasatava Y. MetalS2: a tool for the structural alignment of minimal functional sites in metal-binding proteins and nucleic acids. J Chem Inf Model 2013; 53:3064-75. [PMID: 24117467 DOI: 10.1021/ci400459w] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We developed a new software tool, MetalS(2), for the structural alignment of Minimal Functional Sites (MFSs) in metal-binding biological macromolecules. MFSs are 3D templates that describe the local environment around the metal(s) independently of the larger context of the macromolecular structure. Such local environment has a determinant role in tuning the chemical reactivity of the metal, ultimately contributing to the functional properties of the whole system. On our example data sets, MetalS(2) unveiled structural similarities that other programs for protein structure comparison do not consistently point out and overall identified a larger number of structurally similar MFSs. MetalS(2) supports the comparison of MFSs harboring different metals and/or with different nuclearity and is available both as a stand-alone program and a Web tool ( http://metalweb.cerm.unifi.it/tools/metals2/).
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Affiliation(s)
- Claudia Andreini
- Magnetic Resonance Center (CERM) - University of Florence , Via L. Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy
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Laitaoja M, Valjakka J, Jänis J. Zinc coordination spheres in protein structures. Inorg Chem 2013; 52:10983-91. [PMID: 24059258 DOI: 10.1021/ic401072d] [Citation(s) in RCA: 166] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Zinc metalloproteins are one of the most abundant and structurally diverse proteins in nature. In these proteins, the Zn(II) ion possesses a multifunctional role as it stabilizes the fold of small zinc fingers, catalyzes essential reactions in enzymes of all six classes, or assists in the formation of biological oligomers. Previously, a number of database surveys have been conducted on zinc proteins to gain broader insights into their rich coordination chemistry. However, many of these surveys suffer from severe flaws and misinterpretations or are otherwise limited. To provide a more comprehensive, up-to-date picture on zinc coordination environments in proteins, zinc containing protein structures deposited in the Protein Data Bank (PDB) were analyzed in detail. A statistical analysis in terms of zinc coordinating amino acids, metal-to-ligand bond lengths, coordination number, and structural classification was performed, revealing coordination spheres from classical tetrahedral cysteine/histidine binding sites to more complex binuclear sites with carboxylated lysine residues. According to the results, coordination spheres of hundreds of crystal structures in the PDB could be misinterpreted due to symmetry-related molecules or missing electron densities for ligands. The analysis also revealed increasing average metal-to-ligand bond length as a function of crystallographic resolution, which should be taken into account when interrogating metal ion binding sites. Moreover, one-third of the zinc ions present in crystal structures are artifacts, merely aiding crystal formation and packing with no biological significance. Our analysis provides solid evidence that a minimal stable zinc coordination sphere is made up by four ligands and adopts a tetrahedral coordination geometry.
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Affiliation(s)
- Mikko Laitaoja
- University of Eastern Finland , Department of Chemistry, P.O. Box 111, FI-80101 Joensuu, Finland
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