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Joiret M, Kerff F, Rapino F, Close P, Geris L. Reversing the relative time courses of the peptide bond reaction with oligopeptides of different lengths and charged amino acid distributions in the ribosome exit tunnel. Comput Struct Biotechnol J 2024; 23:2453-2464. [PMID: 38882677 PMCID: PMC11179572 DOI: 10.1016/j.csbj.2024.05.045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 05/10/2024] [Accepted: 05/27/2024] [Indexed: 06/18/2024] Open
Abstract
The kinetics of the protein elongation cycle by the ribosome depends on intertwined factors. One of these factors is the electrostatic interaction of the nascent protein with the ribosome exit tunnel. In this computational biology theoretical study, we focus on the rate of the peptide bond formation and its dependence on the ribosome exit tunnel electrostatic potential profile. We quantitatively predict how oligopeptides of variable lengths can affect the peptide bond formation rate. We applied the Michaelis-Menten model as previously extended to incorporate the mechano-biochemical effects of forces on the rate of reaction at the catalytic site of the ribosome. For a given pair of carboxy-terminal amino acid substrate at the P- and an aminoacyl-tRNA at the A-sites, the relative time courses of the peptide bond formation reaction can be reversed depending on the oligopeptide sequence embedded in the tunnel and their variable lengths from the P-site. The reversal is predicted to occur from a shift in positions of charged amino acids upstream in the oligopeptidyl-tRNA at the P-site. The position shift must be adjusted by clever design of the oligopeptide probes using the electrostatic potential profile along the exit tunnel axial path. These predicted quantitative results bring strong evidence of the importance and relative contribution of the electrostatic interaction of the ribosome exit tunnel with the nascent peptide chain during elongation.
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Affiliation(s)
- Marc Joiret
- Biomechanics Research Unit, GIGA In Silico Medicine, Liège University, CHU-B34(+5) 1 Avenue de l'Hôpital, 4000 Liège, Belgium
| | - Frederic Kerff
- UR InBios Centre d'Ingénierie des Protéines, Liège University, Bât B6a, Allèe du 6 Août, 19, B-4000 Liège, Belgium
| | - Francesca Rapino
- Cancer Signaling, GIGA Stem Cells, Liège University, CHU-B34(+2) 1 Avenue de l'Hôpital, B-4000 Liège, Belgium
| | - Pierre Close
- Cancer Signaling, GIGA Stem Cells, Liège University, CHU-B34(+2) 1 Avenue de l'Hôpital, B-4000 Liège, Belgium
| | - Liesbet Geris
- Biomechanics Research Unit, GIGA In Silico Medicine, Liège University, CHU-B34(+5) 1 Avenue de l'Hôpital, 4000 Liège, Belgium
- Skeletal Biology & Engineering Research Center, KU Leuven, ON I Herestraat 49 - Box 813, 3000 Leuven, Belgium
- Biomechanics Section, KU Leuven, Celestijnenlaan 300C - Box 2419, B-3001 Heverlee, Belgium
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2
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Byju S, Hassan A, Whitford PC. The energy landscape of the ribosome. Biopolymers 2024; 115:e23570. [PMID: 38051695 DOI: 10.1002/bip.23570] [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: 08/27/2023] [Revised: 10/17/2023] [Accepted: 11/08/2023] [Indexed: 12/07/2023]
Abstract
The ribosome is a prototypical assembly that can be used to establish general principles and techniques for the study of biological molecular machines. Motivated by the fact that the dynamics of every biomolecule is governed by an underlying energy landscape, there has been great interest to understand and quantify ribosome energetics. In the present review, we will focus on theoretical and computational strategies for probing the interactions that shape the energy landscape of the ribosome, with an emphasis on more recent studies of the elongation cycle. These efforts include the application of quantum mechanical methods for describing chemical kinetics, as well as classical descriptions to characterize slower (microsecond to millisecond) large-scale (10-100 Å) rearrangements, where motion is described in terms of diffusion across an energy landscape. Together, these studies provide broad insights into the factors that control a diverse range of dynamical processes in this assembly.
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Affiliation(s)
- Sandra Byju
- Center for Theoretical Biological Physics, Northeastern University, Boston, Massachusetts, USA
- Department of Physics, Northeastern University, Boston, Massachusetts, USA
| | - Asem Hassan
- Department of Chemistry, The University of Texas at Austin, Austin, Texas, United States
| | - Paul C Whitford
- Center for Theoretical Biological Physics, Northeastern University, Boston, Massachusetts, USA
- Department of Physics, Northeastern University, Boston, Massachusetts, USA
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3
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Ormazábal A, Palma J, Pierdominici-Sottile G. Dynamics and Function of sRNA/mRNAs Under the Scrutiny of Computational Simulation Methods. Methods Mol Biol 2024; 2741:207-238. [PMID: 38217656 DOI: 10.1007/978-1-0716-3565-0_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2024]
Abstract
Molecular dynamics simulations have proved extremely useful in investigating the functioning of proteins with atomic-scale resolution. Many applications to the study of RNA also exist, and their number increases by the day. However, implementing MD simulations for RNA molecules in solution faces challenges that the MD practitioner must be aware of for the appropriate use of this tool. In this chapter, we present the fundamentals of MD simulations, in general, and the peculiarities of RNA simulations, in particular. We discuss the strengths and limitations of the technique and provide examples of its application to elucidate small RNA's performance.
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Affiliation(s)
- Agustín Ormazábal
- Departmento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas, CONICET, Godoy Cruz, CABA, Argentina
| | - Juliana Palma
- Departmento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas, CONICET, Godoy Cruz, CABA, Argentina
| | - Gustavo Pierdominici-Sottile
- Departmento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Buenos Aires, Argentina.
- Consejo Nacional de Investigaciones Científicas y Técnicas, CONICET, Godoy Cruz, CABA, Argentina.
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4
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Steffen J. Caracal: A Versatile Ring Polymer Molecular Dynamics Simulation Package. J Chem Theory Comput 2023; 19:5334-5355. [PMID: 37555628 DOI: 10.1021/acs.jctc.3c00568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2023]
Abstract
A new open-source program package named Caracal covering simulations of molecular systems with ring polymer molecular dynamics (RPMD) is presented. It combines a powerful RPMD implementation including chemical reaction rate calculations and biased periodic and nonperiodic samplings with a collection of easy to set up potential energy surface (PES) methodologies, thus delivering an all-inclusive approach. Most implemented PESs are based on the QMDFF and EVB-QMDFF methods. Where the quantum mechanically derived force field (QMDFF) can be set up for an arbitrary molecular system in a black-box fashion, the empirical valence bond (EVB)-QMDFF connects two QMDFFs and is able to represent the PES of a chemical reaction. With our previously published flavors of this composite method, PESs for almost arbitrary gas phase thermal ground state reactions can be set up. Given an optimized reaction path, the mechanism of the reaction can be classified and RPMD rate constants can be obtained via umbrella sampling and recrossing calculations on an EVB-QMDFF PES. Further, QMDFFs can be polymerized for the description of liquid systems. In this paper, the internal structure as well as the handling philosophy of Caracal are outlined. Further, examples of the different possible kinds of calculations are given.
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Affiliation(s)
- Julien Steffen
- Chair of Theoretical Chemistry, Friedrich-Alexander University Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Bavaria, Germany
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5
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Tirumalai MR, Rivas M, Tran Q, Fox GE. The Peptidyl Transferase Center: a Window to the Past. Microbiol Mol Biol Rev 2021; 85:e0010421. [PMID: 34756086 PMCID: PMC8579967 DOI: 10.1128/mmbr.00104-21] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
In his 2001 article, "Translation: in retrospect and prospect," the late Carl Woese made a prescient observation that there was a need for the then-current view of translation to be "reformulated to become an all-embracing perspective about which 21st century Biology can develop" (RNA 7:1055-1067, 2001, https://doi.org/10.1017/s1355838201010615). The quest to decipher the origins of life and the road to the genetic code are both inextricably linked with the history of the ribosome. After over 60 years of research, significant progress in our understanding of how ribosomes work has been made. Particularly attractive is a model in which the ribosome may facilitate an ∼180° rotation of the CCA end of the tRNA from the A-site to the P-site while the acceptor stem of the tRNA would then undergo a translation from the A-site to the P-site. However, the central question of how the ribosome originated remains unresolved. Along the path from a primitive RNA world or an RNA-peptide world to a proto-ribosome world, the advent of the peptidyl transferase activity would have been a seminal event. This functionality is now housed within a local region of the large-subunit (LSU) rRNA, namely, the peptidyl transferase center (PTC). The PTC is responsible for peptide bond formation during protein synthesis and is usually considered to be the oldest part of the modern ribosome. What is frequently overlooked is that by examining the origins of the PTC itself, one is likely going back even further in time. In this regard, it has been proposed that the modern PTC originated from the association of two smaller RNAs that were once independent and now comprise a pseudosymmetric region in the modern PTC. Could such an association have survived? Recent studies have shown that the extant PTC is largely depleted of ribosomal protein interactions. It is other elements like metallic ion coordination and nonstandard base/base interactions that would have had to stabilize the association of RNAs. Here, we present a detailed review of the literature focused on the nature of the extant PTC and its proposed ancestor, the proto-ribosome.
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Affiliation(s)
- Madhan R. Tirumalai
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, USA
| | - Mario Rivas
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, USA
| | - Quyen Tran
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, USA
| | - George E. Fox
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, USA
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6
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Zhang L, Wang Y, Dai H, Zhou J. Structural and functional studies revealed key mechanisms underlying elongation step of protein translation. Acta Biochim Biophys Sin (Shanghai) 2020; 52:749-756. [PMID: 32400848 DOI: 10.1093/abbs/gmaa046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Indexed: 11/12/2022] Open
Abstract
The ribosome is an ancient and universally conserved macromolecular machine that synthesizes proteins in all organisms. Since the discovery of the ribosome by electron microscopy in the mid-1950s, rapid progress has been made in research on it, regarding its architecture and functions. As a machine that synthesizes polypeptides, the sequential addition of amino acids to a growing polypeptide chain occurs during a phase called the elongation cycle. This is the core step of protein translation and is highly conserved between bacteria and eukarya. The elongation cycle involves codon recognition by aminoacyl tRNAs, catalysis of peptide bond formation, and the most complex operation of translation-translocation. In this review, we discuss the fundamental results from structural and functional studies over the past decades that have led to understanding of the three key questions underlying translation.
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Affiliation(s)
- Ling Zhang
- Life Sciences Institute, Zhejiang University, Hangzhou 310058, China
| | - Yinghui Wang
- Life Sciences Institute, Zhejiang University, Hangzhou 310058, China
| | - Hong Dai
- Life Sciences Institute, Zhejiang University, Hangzhou 310058, China
| | - Jie Zhou
- Life Sciences Institute, Zhejiang University, Hangzhou 310058, China
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7
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Kazemi M, Socan J, Himo F, Åqvist J. Mechanistic alternatives for peptide bond formation on the ribosome. Nucleic Acids Res 2019; 46:5345-5354. [PMID: 29746669 PMCID: PMC6009655 DOI: 10.1093/nar/gky367] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 04/26/2018] [Indexed: 02/04/2023] Open
Abstract
The peptidyl transfer reaction on the large ribosomal subunit depends on the protonation state of the amine nucleophile and exhibits a large kinetic solvent isotope effect (KSIE ∼8). In contrast, the related peptidyl-tRNA hydrolysis reaction involved in termination shows a KSIE of ∼4 and a pH-rate profile indicative of base catalysis. It is, however, unclear why these reactions should proceed with different mechanisms, as the experimental data suggests. One explanation is that two competing mechanisms may be operational in the peptidyl transferase center (PTC). Herein, we explored this possibility by re-examining the previously proposed proton shuttle mechanism and testing the feasibility of general base catalysis also for peptide bond formation. We employed a large cluster model of the active site and different reaction mechanisms were evaluated by density functional theory calculations. In these calculations, the proton shuttle and general base mechanisms both yield activation energies comparable to the experimental values. However, only the proton shuttle mechanism is found to be consistent with the experimentally observed pH-rate profile and the KSIE. This suggests that the PTC promotes the proton shuttle mechanism for peptide bond formation, while prohibiting general base catalysis, although the detailed mechanism by which general base catalysis is excluded remains unclear.
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Affiliation(s)
- Masoud Kazemi
- Department of Cell and Molecular Biology, Box 596, Uppsala University, BMC, SE-751 24 Uppsala, Sweden.,Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Jaka Socan
- Department of Cell and Molecular Biology, Box 596, Uppsala University, BMC, SE-751 24 Uppsala, Sweden
| | - Fahmi Himo
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Johan Åqvist
- Department of Cell and Molecular Biology, Box 596, Uppsala University, BMC, SE-751 24 Uppsala, Sweden
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8
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Pavlov MY, Ehrenberg M. Substrate-Induced Formation of Ribosomal Decoding Center for Accurate and Rapid Genetic Code Translation. Annu Rev Biophys 2019; 47:525-548. [PMID: 29792818 DOI: 10.1146/annurev-biophys-060414-034148] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Accurate translation of genetic information is crucial for synthesis of functional proteins in all organisms. We use recent experimental data to discuss how induced fit affects accuracy of initial codon selection on the ribosome by aminoacyl transfer RNA in ternary complex ( T3) with elongation factor Tu (EF-Tu) and guanosine-5'-triphosphate (GTP). We define actual accuracy ([Formula: see text]) of a particular protein synthesis system as its current accuracy and the effective selectivity ([Formula: see text]) as [Formula: see text] in the limit of zero ribosomal binding affinity for T3. Intrinsic selectivity ([Formula: see text]), defined as the upper thermodynamic limit of [Formula: see text], is determined by the free energy difference between near-cognate and cognate T3 in the pre-GTP hydrolysis state on the ribosome. [Formula: see text] is much larger than [Formula: see text], suggesting the possibility of a considerable increase in [Formula: see text] and [Formula: see text] at negligible kinetic cost. Induced fit increases [Formula: see text] and [Formula: see text] without affecting [Formula: see text], and aminoglycoside antibiotics reduce [Formula: see text] and [Formula: see text] at unaltered [Formula: see text].
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Affiliation(s)
- Michael Y Pavlov
- Department of Cell and Molecular Biology, Uppsala University, Uppsala 75124, Sweden;
| | - Måns Ehrenberg
- Department of Cell and Molecular Biology, Uppsala University, Uppsala 75124, Sweden;
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9
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Melnikov SV, Khabibullina NF, Mairhofer E, Vargas-Rodriguez O, Reynolds NM, Micura R, Söll D, Polikanov YS. Mechanistic insights into the slow peptide bond formation with D-amino acids in the ribosomal active site. Nucleic Acids Res 2019; 47:2089-2100. [PMID: 30520988 PMCID: PMC6393236 DOI: 10.1093/nar/gky1211] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 11/14/2018] [Accepted: 11/20/2018] [Indexed: 12/24/2022] Open
Abstract
During protein synthesis, ribosomes discriminate chirality of amino acids and prevent incorporation of D-amino acids into nascent proteins by slowing down the rate of peptide bond formation. Despite this phenomenon being known for nearly forty years, no structures have ever been reported that would explain the poor reactivity of D-amino acids. Here we report a 3.7Å-resolution crystal structure of a bacterial ribosome in complex with a D-aminoacyl-tRNA analog bound to the A site. Although at this resolution we could not observe individual chemical groups, we could unambiguously define the positions of the D-amino acid side chain and the amino group based on chemical restraints. The structure reveals that similarly to L-amino acids, the D-amino acid binds the ribosome by inserting its side chain into the ribosomal A-site cleft. This binding mode does not allow optimal nucleophilic attack of the peptidyl-tRNA by the reactive α-amino group of a D-amino acid. Also, our structure suggests that the D-amino acid cannot participate in hydrogen-bonding with the P-site tRNA that is required for the efficient proton transfer during peptide bond formation. Overall, our work provides the first mechanistic insight into the ancient mechanism that helps living cells ensure the stereochemistry of protein synthesis.
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Affiliation(s)
- Sergey V Melnikov
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
| | - Nelli F Khabibullina
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Elisabeth Mairhofer
- Institute of Organic Chemistry at Leopold Franzens University, A-6020 Innsbruck, Austria
| | - Oscar Vargas-Rodriguez
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
| | - Noah M Reynolds
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
| | - Ronald Micura
- Institute of Organic Chemistry at Leopold Franzens University, A-6020 Innsbruck, Austria
| | - Dieter Söll
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
- Department of Chemistry, Yale University, New Haven, CT 06520, USA
| | - Yury S Polikanov
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, IL 60607, USA
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10
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Šponer J, Bussi G, Krepl M, Banáš P, Bottaro S, Cunha RA, Gil-Ley A, Pinamonti G, Poblete S, Jurečka P, Walter NG, Otyepka M. RNA Structural Dynamics As Captured by Molecular Simulations: A Comprehensive Overview. Chem Rev 2018; 118:4177-4338. [PMID: 29297679 PMCID: PMC5920944 DOI: 10.1021/acs.chemrev.7b00427] [Citation(s) in RCA: 336] [Impact Index Per Article: 56.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Indexed: 12/14/2022]
Abstract
With both catalytic and genetic functions, ribonucleic acid (RNA) is perhaps the most pluripotent chemical species in molecular biology, and its functions are intimately linked to its structure and dynamics. Computer simulations, and in particular atomistic molecular dynamics (MD), allow structural dynamics of biomolecular systems to be investigated with unprecedented temporal and spatial resolution. We here provide a comprehensive overview of the fast-developing field of MD simulations of RNA molecules. We begin with an in-depth, evaluatory coverage of the most fundamental methodological challenges that set the basis for the future development of the field, in particular, the current developments and inherent physical limitations of the atomistic force fields and the recent advances in a broad spectrum of enhanced sampling methods. We also survey the closely related field of coarse-grained modeling of RNA systems. After dealing with the methodological aspects, we provide an exhaustive overview of the available RNA simulation literature, ranging from studies of the smallest RNA oligonucleotides to investigations of the entire ribosome. Our review encompasses tetranucleotides, tetraloops, a number of small RNA motifs, A-helix RNA, kissing-loop complexes, the TAR RNA element, the decoding center and other important regions of the ribosome, as well as assorted others systems. Extended sections are devoted to RNA-ion interactions, ribozymes, riboswitches, and protein/RNA complexes. Our overview is written for as broad of an audience as possible, aiming to provide a much-needed interdisciplinary bridge between computation and experiment, together with a perspective on the future of the field.
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Affiliation(s)
- Jiří Šponer
- Institute of Biophysics of the Czech Academy of Sciences , Kralovopolska 135 , Brno 612 65 , Czech Republic
| | - Giovanni Bussi
- Scuola Internazionale Superiore di Studi Avanzati , Via Bonomea 265 , Trieste 34136 , Italy
| | - Miroslav Krepl
- Institute of Biophysics of the Czech Academy of Sciences , Kralovopolska 135 , Brno 612 65 , Czech Republic
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science , Palacky University Olomouc , 17. listopadu 12 , Olomouc 771 46 , Czech Republic
| | - Pavel Banáš
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science , Palacky University Olomouc , 17. listopadu 12 , Olomouc 771 46 , Czech Republic
| | - Sandro Bottaro
- Structural Biology and NMR Laboratory, Department of Biology , University of Copenhagen , Copenhagen 2200 , Denmark
| | - Richard A Cunha
- Scuola Internazionale Superiore di Studi Avanzati , Via Bonomea 265 , Trieste 34136 , Italy
| | - Alejandro Gil-Ley
- Scuola Internazionale Superiore di Studi Avanzati , Via Bonomea 265 , Trieste 34136 , Italy
| | - Giovanni Pinamonti
- Scuola Internazionale Superiore di Studi Avanzati , Via Bonomea 265 , Trieste 34136 , Italy
| | - Simón Poblete
- Scuola Internazionale Superiore di Studi Avanzati , Via Bonomea 265 , Trieste 34136 , Italy
| | - Petr Jurečka
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science , Palacky University Olomouc , 17. listopadu 12 , Olomouc 771 46 , Czech Republic
| | - Nils G Walter
- Single Molecule Analysis Group and Center for RNA Biomedicine, Department of Chemistry , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Michal Otyepka
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science , Palacky University Olomouc , 17. listopadu 12 , Olomouc 771 46 , Czech Republic
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11
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Bock LV, Kolář MH, Grubmüller H. Molecular simulations of the ribosome and associated translation factors. Curr Opin Struct Biol 2017; 49:27-35. [PMID: 29202442 DOI: 10.1016/j.sbi.2017.11.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/15/2017] [Accepted: 11/16/2017] [Indexed: 01/15/2023]
Abstract
The ribosome is a macromolecular complex which is responsible for protein synthesis in all living cells according to their transcribed genetic information. Using X-ray crystallography and, more recently, cryo-electron microscopy (cryo-EM), the structure of the ribosome was resolved at atomic resolution in many functional and conformational states. Molecular dynamics simulations have added information on dynamics and energetics to the available structural information, thereby have bridged the gap to the kinetics obtained from single-molecule and bulk experiments. Here, we review recent computational studies that brought notable insights into ribosomal structure and function.
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Affiliation(s)
- Lars V Bock
- Department of Theoretical and Computational Biophysics, Am Faßberg 11, Göttingen, Germany
| | - Michal H Kolář
- Department of Theoretical and Computational Biophysics, Am Faßberg 11, Göttingen, Germany
| | - Helmut Grubmüller
- Department of Theoretical and Computational Biophysics, Am Faßberg 11, Göttingen, Germany.
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12
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Mechanistic Insights Into Catalytic RNA-Protein Complexes Involved in Translation of the Genetic Code. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2017. [PMID: 28683922 DOI: 10.1016/bs.apcsb.2017.04.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
The contemporary world is an "RNA-protein world" rather than a "protein world" and tracing its evolutionary origins is of great interest and importance. The different RNAs that function in close collaboration with proteins are involved in several key physiological processes, including catalysis. Ribosome-the complex megadalton cellular machinery that translates genetic information encoded in nucleotide sequence to amino acid sequence-epitomizes such an association between RNA and protein. RNAs that can catalyze biochemical reactions are known as ribozymes. They usually employ general acid-base catalytic mechanism, often involving the 2'-OH of RNA that activates and/or stabilizes a nucleophile during the reaction pathway. The protein component of such RNA-protein complexes (RNPCs) mostly serves as a scaffold which provides an environment conducive for the RNA to function, or as a mediator for other interacting partners. In this review, we describe those RNPCs that are involved at different stages of protein biosynthesis and in which RNA performs the catalytic function; the focus of the account is on highlighting mechanistic aspects of these complexes. We also provide a perspective on such associations in the context of proofreading during translation of the genetic code. The latter aspect is not much appreciated and recent works suggest that this is an avenue worth exploring, since an understanding of the subject can provide useful insights into how RNAs collaborate with proteins to ensure fidelity during these essential cellular processes. It may also aid in comprehending evolutionary aspects of such associations.
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13
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Lehmann J. Induced fit of the peptidyl-transferase center of the ribosome and conformational freedom of the esterified amino acids. RNA (NEW YORK, N.Y.) 2017; 23:229-239. [PMID: 27879432 PMCID: PMC5238797 DOI: 10.1261/rna.057273.116] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 11/18/2016] [Indexed: 06/06/2023]
Abstract
The catalytic site of most enzymes can efficiently handle only one substrate. In contrast, the ribosome is capable of polymerizing at a similar rate at least 20 different kinds of amino acids from aminoacyl-tRNA carriers while using just one catalytic site, the peptidyl-transferase center (PTC). An induced-fit mechanism has been uncovered in the PTC, but a possible connection between this mechanism and the uniform handling of the substrates has not been investigated. We present an analysis of published ribosome structures supporting the hypothesis that the induced fit eliminates unreactive rotamers predominantly populated for some A-site aminoacyl esters before induction. We show that this hypothesis is fully consistent with the wealth of kinetic data obtained with these substrates. Our analysis reveals that induction constrains the amino acids into a reactive conformation in a side-chain independent manner. It allows us to highlight the rationale of the PTC structural organization, which confers to the ribosome the very unusual ability to handle large as well as small substrates.
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Affiliation(s)
- Jean Lehmann
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Campus Paris-Saclay, 91198 Gif-sur-Yvette, France
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14
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Amrein BA, Steffen-Munsberg F, Szeler I, Purg M, Kulkarni Y, Kamerlin SCL. CADEE: Computer-Aided Directed Evolution of Enzymes. IUCRJ 2017; 4:50-64. [PMID: 28250941 PMCID: PMC5331465 DOI: 10.1107/s2052252516018017] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 11/09/2016] [Indexed: 05/10/2023]
Abstract
The tremendous interest in enzymes as biocatalysts has led to extensive work in enzyme engineering, as well as associated methodology development. Here, a new framework for computer-aided directed evolution of enzymes (CADEE) is presented which allows a drastic reduction in the time necessary to prepare and analyze in silico semi-automated directed evolution of enzymes. A pedagogical example of the application of CADEE to a real biological system is also presented in order to illustrate the CADEE workflow.
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Affiliation(s)
- Beat Anton Amrein
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, BMC Box 596, S-751 24 Uppsala, Sweden
| | - Fabian Steffen-Munsberg
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, BMC Box 596, S-751 24 Uppsala, Sweden
| | - Ireneusz Szeler
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, BMC Box 596, S-751 24 Uppsala, Sweden
| | - Miha Purg
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, BMC Box 596, S-751 24 Uppsala, Sweden
| | - Yashraj Kulkarni
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, BMC Box 596, S-751 24 Uppsala, Sweden
| | - Shina Caroline Lynn Kamerlin
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, BMC Box 596, S-751 24 Uppsala, Sweden
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15
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Kazemi M, Himo F, Åqvist J. Peptide Release on the Ribosome Involves Substrate-Assisted Base Catalysis. ACS Catal 2016. [DOI: 10.1021/acscatal.6b02842] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Masoud Kazemi
- Department
of Cell and Molecular Biology, Uppsala University, Box 596, BMC, SE-751 24 Uppsala, Sweden
| | - Fahmi Himo
- Department
of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106
91 Stockholm, Sweden
| | - Johan Åqvist
- Department
of Cell and Molecular Biology, Uppsala University, Box 596, BMC, SE-751 24 Uppsala, Sweden
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16
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Sharma B, Paul S. Action of Caffeine as an Amyloid Inhibitor in the Aggregation of Aβ16–22 Peptides. J Phys Chem B 2016; 120:9019-33. [DOI: 10.1021/acs.jpcb.6b03892] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Bhanita Sharma
- Department of Chemistry, Indian Institute of Technology, Guwahati 781039, Assam, India
| | - Sandip Paul
- Department of Chemistry, Indian Institute of Technology, Guwahati 781039, Assam, India
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17
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Sharma B, Kalita S, Paul A, Mandal B, Paul S. The role of caffeine as an inhibitor in the aggregation of amyloid forming peptides: a unified molecular dynamics simulation and experimental study. RSC Adv 2016. [DOI: 10.1039/c6ra17602j] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
10 : 1 or more caffeine to SwP ratio can prevent the formation of β-sheet conformation.
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Affiliation(s)
- Bhanita Sharma
- Department of Chemistry
- Indian Institute of Technology
- Guwahati
- India
| | - Sourav Kalita
- Department of Chemistry
- Indian Institute of Technology
- Guwahati
- India
| | - Ashim Paul
- Department of Chemistry
- Indian Institute of Technology
- Guwahati
- India
| | | | - Sandip Paul
- Department of Chemistry
- Indian Institute of Technology
- Guwahati
- India
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18
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Åqvist J, Kamerlin SCL. Exceptionally large entropy contributions enable the high rates of GTP hydrolysis on the ribosome. Sci Rep 2015; 5:15817. [PMID: 26497916 PMCID: PMC4620562 DOI: 10.1038/srep15817] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 10/06/2015] [Indexed: 11/09/2022] Open
Abstract
Protein synthesis on the ribosome involves hydrolysis of GTP in several key steps of the mRNA translation cycle. These steps are catalyzed by the translational GTPases of which elongation factor Tu (EF-Tu) is the fastest GTPase known. Here, we use extensive computer simulations to explore the origin of its remarkably high catalytic rate on the ribosome and show that it is made possible by a very large positive activation entropy. This entropy term (TΔS(‡)) amounts to more than 7 kcal/mol at 25 °C. It is further found to be characteristic of the reaction mechanism utilized by the translational, but not other, GTPases and it enables these enzymes to attain hydrolysis rates exceeding 500 s(-1). This entropy driven mechanism likely reflects the very high selection pressure on the speed of protein synthesis, which drives the rate of each individual GTPase towards maximal turnover rate of the whole translation cycle.
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Affiliation(s)
- Johan Åqvist
- Dept. of Cell &Molecular Biology, Uppsala University, Biomedical Center, Box 596, SE-751 24 Uppsala, Sweden
| | - Shina C L Kamerlin
- Dept. of Cell &Molecular Biology, Uppsala University, Biomedical Center, Box 596, SE-751 24 Uppsala, Sweden
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19
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A theoretical model investigation of peptide bond formation involving two water molecules in ribosome supports the two-step and eight membered ring mechanism. Chem Phys 2015. [DOI: 10.1016/j.chemphys.2015.01.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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20
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Monajemi H, Mohd Zain S, Wan Abdullah WAT. The P-site A76 2′-OH acts as a peptidyl shuttle in a stepwise peptidyl transfer mechanism. RSC Adv 2015. [DOI: 10.1039/c5ra02767e] [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] Open
Abstract
The P-site-A76-2′OH transfers the polypeptide chain to the A-site α-amine and A2451 facilitates this transfer by acting as proton shuttle.
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Affiliation(s)
- Hadieh Monajemi
- Department of Physics
- Faculty of Science
- Universiti Malaya
- 50603 Kuala Lumpur
- Malaysia
| | - Sharifuddin Mohd Zain
- Department of Chemistry
- Faculty of Science
- Universiti Malaya
- 50603 Kuala Lumpur
- Malaysia
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21
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Acosta-Silva C, Bertran J, Branchadell V, Oliva A. Theoretical Study on Two-Step Mechanisms of Peptide Release in the Ribosome. J Phys Chem B 2014; 118:5717-29. [DOI: 10.1021/jp501246a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Carles Acosta-Silva
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Joan Bertran
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Vicenç Branchadell
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Antoni Oliva
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
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22
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Heavy water reduces GFP expression in prokaryotic cell-free assays at the translation level while stimulating its transcription. BIOMED RESEARCH INTERNATIONAL 2013; 2013:592745. [PMID: 24455706 PMCID: PMC3886400 DOI: 10.1155/2013/592745] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 12/06/2013] [Accepted: 12/06/2013] [Indexed: 11/17/2022]
Abstract
The in vitro proliferation of prokaryotic and eukaryotic cells is remarkably hampered in the presence of heavy water (D2O). Impairment of gene expression at the transcription or translation level can be the base for this effect. However, insights into the underlying mechanisms are lacking. Here, we employ a cell-free expression system for the quantitative analysis of the effect of increasing percentages of D2O on the kinetics of in-vitro GFP expression. Experiments are designed to discriminate the rates of transcription, translation, and protein folding using pDNA and mRNA vectors, respectively. We find that D2O significantly stimulates GFP expression at the transcription level but acts as a suppressor at translation and maturation (folding) in a linear dose-dependent manner. At a D2O concentration of 60%, the GFP expression rate was reduced to 40% of an undisturbed sample. We observed a similar inhibition of GFP expression by D2O in a recombinant Escherichia coli strain, although the inhibitory effect is less pronounced. These results demonstrate the suitability of cell-free systems for quantifying the impact of heavy water on gene expression and establish a platform to further assess the potential therapeutic use of heavy water as antiproliferative agent.
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23
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Affiliation(s)
| | - V. Ramakrishnan
- MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom; ,
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24
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Rodnina MV. The ribosome as a versatile catalyst: reactions at the peptidyl transferase center. Curr Opin Struct Biol 2013; 23:595-602. [PMID: 23711800 DOI: 10.1016/j.sbi.2013.04.012] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 04/10/2013] [Indexed: 11/29/2022]
Abstract
In all contemporary organisms, the active site of the ribosome--the peptidyl transferase center--catalyzes two distinct reactions, peptide bond formation between peptidyl-tRNA and aminoacyl-tRNA as well as the hydrolysis of peptidyl-tRNA with the help of a release factor. However, when provided with appropriate substrates, ribosomes can also catalyze a broad range of other chemical reaction, which provides the basis for orthogonal translation and synthesis of alloproteins from unnatural building blocks. Advances in understanding the mechanisms of the two ubiquitous reactions, the peptide bond formation and peptide release, provide insights into the versatility of the active site of the ribosome. Release factors 1 and 2 and elongation factor P are auxiliary factors that augment the intrinsic catalytic activity of the ribosome in special cases.
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Affiliation(s)
- Marina V Rodnina
- Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, 37077 Goettingen, Germany.
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25
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Acosta-Silva C, Bertran J, Branchadell V, Oliva A. Quantum Mechanical Study on the Mechanism of Peptide Release in the Ribosome. J Phys Chem B 2013; 117:3503-15. [DOI: 10.1021/jp3110248] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Carles Acosta-Silva
- Departament de Química, Universitat Autònoma
de Barcelona, 08193 Bellaterra, Spain
| | - Joan Bertran
- Departament de Química, Universitat Autònoma
de Barcelona, 08193 Bellaterra, Spain
| | - Vicenç Branchadell
- Departament de Química, Universitat Autònoma
de Barcelona, 08193 Bellaterra, Spain
| | - Antoni Oliva
- Departament de Química, Universitat Autònoma
de Barcelona, 08193 Bellaterra, Spain
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26
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Byun BJ, Kang YK. A mechanistic study supports a two-step mechanism for peptide bond formation on the ribosome. Phys Chem Chem Phys 2013; 15:14931-5. [DOI: 10.1039/c3cp51082d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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27
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Fukushima K, Iwahashi H, Nishikimi M. ONIOM Study of a Proton Shuttle-Catalyzed Stepwise Mechanism for Peptide Bond Formation in the Ribosome. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2012. [DOI: 10.1246/bcsj.20120144] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
| | | | - Morimitsu Nishikimi
- Department of Food Science and Nutrition, Faculty of Human Life and Environmental Sciences, Nagoya Women’s University
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28
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Monajemi H, Daud MN, Mohd Zain S, Wan Abdullah WAT. ONIOM and ab-initio calculations on the mechanism of uncatalyzed peptide bond formation. Biochem Cell Biol 2012; 90:691-700. [PMID: 23016605 DOI: 10.1139/o2012-027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Finding a proper transition structure for the peptide bond formation process can lead one to a better understanding of the role of ribosome in catalyzing this reaction. Using computer simulations, we performed the potential energy surface scan on the ester bond dissociation of P-site aminoacyl-tRNA and the peptide bond formation of P-site and A-site amino acids. The full fragments of initiator tRNA(i)(met) and elongator tRNA(phe) are attached to both cognate and non-cognate amino acids as the P-site substrate. The A-site amino acid for all four calculations is methionine. We used ONIOM calculations to reduce the computational cost. Our study illustrates the reduced rate of peptide bond formation for misacylated tRNA(i)(met) in the absence of ribosomal bases. The misacylated elongator tRNA(phe), however, did not show any difference in its PES compared with that for the phe-tRNA(phe). This demonstrates the structural specification of initiator tRNA(i)(met) for the amino acids side chain.
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Affiliation(s)
- Hadieh Monajemi
- Department of Physics, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Malaysia.
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29
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Xu J, Zhang JZH, Xiang Y. Ab Initio QM/MM Free Energy Simulations of Peptide Bond Formation in the Ribosome Support an Eight-Membered Ring Reaction Mechanism. J Am Chem Soc 2012; 134:16424-9. [DOI: 10.1021/ja3076605] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jun Xu
- State Key Laboratory of Precision
Spectroscopy, Institute of Theoretical and Computational Science,
Department of Physics, East China Normal University, Shanghai 200062, China
| | - John Z. H. Zhang
- State Key Laboratory of Precision
Spectroscopy, Institute of Theoretical and Computational Science,
Department of Physics, East China Normal University, Shanghai 200062, China
- Department of Chemistry, New York University, New York, New York 10003, United
States
| | - Yun Xiang
- State Key Laboratory of Precision
Spectroscopy, Institute of Theoretical and Computational Science,
Department of Physics, East China Normal University, Shanghai 200062, China
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30
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Aqvist J, Lind C, Sund J, Wallin G. Bridging the gap between ribosome structure and biochemistry by mechanistic computations. Curr Opin Struct Biol 2012; 22:815-23. [PMID: 22884263 DOI: 10.1016/j.sbi.2012.07.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Revised: 06/14/2012] [Accepted: 07/09/2012] [Indexed: 11/18/2022]
Abstract
The wealth of structural and biochemical data now available for protein synthesis on the ribosome presents major new challenges for computational biochemistry. Apart from technical difficulties in modeling ribosome systems, the complexity of the overall translation cycle with a multitude of different kinetic steps presents a formidable problem for computational efforts where we have only seen the beginning. However, a range of methodologies including molecular dynamics simulations, free energy calculations, molecular docking and quantum chemical approaches have already been put to work with promising results. In particular, the combined efforts of structural biology, biochemistry, kinetics and computational modeling can lead towards a quantitative structure-based description of translation.
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Affiliation(s)
- Johan Aqvist
- Department of Cell and Molecular Biology, Uppsala University, Biomedical Center, Box 596, SE-751 24 Uppsala, Sweden.
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31
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Kingery DA, Strobel SA. Analysis of enzymatic transacylase Brønsted studies with application to the ribosome. Acc Chem Res 2012; 45:495-503. [PMID: 22122380 DOI: 10.1021/ar100162b] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Preferential binding of an enzyme to the transition state relative to the ground state is a key strategy for enzyme catalysis. When there is a difference between the ground and transition state charge distributions, enzymes maximize electrostatic interactions to achieve this enhanced transition state binding. Although the transition state is difficult to observe directly by structural methods, the chemical details of this transient species can be characterized by studies of substituent effects (Brønsted, Hammett, Swain-Scott, etc.) and isotope effects. Brønsted analysis can provide an estimate of transition state charges for the nucleophile and leaving group of a reaction. This Account will discuss the theoretical basis of Brønsted analysis and describe its practical application to the study of transacylase enzyme systems including the peptidyl transferase reaction of the ribosome. The Brønsted coefficient is derived from the linear free energy relationship (LFER) that correlates the acidity (pK(a)) of a reactive atom to the log of its rate constant. The Brønsted coefficient establishes the change in atomic charge as the reaction proceeds from the ground state to the transition state. Bonding events alter the electrostatics of atoms and the extent of bonding can be extrapolated from transition state charges. Therefore, well-defined nucleophile and leaving group transition state charges limit the number of mechanisms that are consistent with a particular transition state. Brønsted results are most informative when interpreted in the context of other mechanistic data, especially for enzymatic studies where an active site may promote a transition state that differs significantly from a prediction based on uncatalyzed solution reactions. Here we review Brønsted analyses performed on transacylases to illustrate how these data enhanced the enzymatic mechanistic studies. Through a systematic comparison of five enzymes, we reveal a wide spectrum of Brønsted values that are possible for what otherwise appear to be similar chemical reactions. The variations in the Brønsted coefficients predict different transition states for the various enzymes. This Account explores an overriding theme in the enzymatic mechanisms that catalysis enhances commensurate bond formation and proton abstraction events. The extent of the two bonding events in relationship to each other can be inferred from the Brønsted coefficient. When viewed in the context of recent ribosomal studies, this interpretation provides mechanistic insights into peptide bond formation.
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Affiliation(s)
- David A. Kingery
- Department of Molecular Biophysics and Biochemistry, Yale University, 260 Whitney Avenue, New Haven, Connecticut 06520, United States
| | - Scott A. Strobel
- Department of Molecular Biophysics and Biochemistry, Yale University, 260 Whitney Avenue, New Haven, Connecticut 06520, United States
- Department of Chemistry, Yale University, 260 Whitney Avenue, New Haven, Connecticut 06520, United States
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32
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Acosta-Silva C, Bertran J, Branchadell V, Oliva A. Quantum-Mechanical Study on the Mechanism of Peptide Bond Formation in the Ribosome. J Am Chem Soc 2012; 134:5817-31. [DOI: 10.1021/ja209558d] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Carles Acosta-Silva
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Joan Bertran
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Vicenç Branchadell
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Antoni Oliva
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
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33
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Carrasco N, Hiller DA, Strobel SA. Minimal Transition State Charge Stabilization of the Oxyanion during Peptide Bond Formation by the Ribosome. Biochemistry 2011; 50:10491-8. [DOI: 10.1021/bi201290s] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Nicolas Carrasco
- Departments of Molecular Biophysics & Biochemistry and Chemistry, Yale University, 260 Whitney Ave., New Haven, Connecticut 06520-81114, United States
| | - David A. Hiller
- Departments of Molecular Biophysics & Biochemistry and Chemistry, Yale University, 260 Whitney Ave., New Haven, Connecticut 06520-81114, United States
| | - Scott A. Strobel
- Departments of Molecular Biophysics & Biochemistry and Chemistry, Yale University, 260 Whitney Ave., New Haven, Connecticut 06520-81114, United States
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34
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Kuhlenkoetter S, Wintermeyer W, Rodnina MV. Different substrate-dependent transition states in the active site of the ribosome. Nature 2011; 476:351-4. [PMID: 21804565 DOI: 10.1038/nature10247] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Accepted: 06/03/2011] [Indexed: 11/09/2022]
Abstract
The active site of the ribosome, the peptidyl transferase centre, catalyses two reactions, namely, peptide bond formation between peptidyl-tRNA and aminoacyl-tRNA as well as the release-factor-dependent hydrolysis of peptidyl-tRNA. Unlike peptide bond formation, peptide release is strongly impaired by mutations of nucleotides within the active site, in particular by base exchanges at position A2602 (refs 1, 2). The 2'-OH group of A76 of the peptidyl-tRNA substrate seems to have a key role in peptide release. According to computational analysis, the 2'-OH may take part in a concerted 'proton shuttle' by which the leaving group is protonated, in analogy to similar current models of peptide bond formation. Here we report kinetic solvent isotope effects and proton inventories (reaction rates measured in buffers with increasing content of deuterated water, D(2)O) of the two reactions catalysed by the active site of the Escherichia coli ribosome. The transition state of the release factor 2 (RF2)-dependent hydrolysis reaction is characterized by the rate-limiting formation of a single strong hydrogen bond. This finding argues against a concerted proton shuttle in the transition state of the hydrolysis reaction. In comparison, the proton inventory for peptide bond formation indicates the rate-limiting formation of three hydrogen bonds with about equal contributions, consistent with a concerted eight-membered proton shuttle in the transition state. Thus, the ribosome supports different rate-limiting transition states for the two reactions that take place in the peptidyl transferase centre.
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Affiliation(s)
- Stephan Kuhlenkoetter
- Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
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35
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Leung EKY, Suslov N, Tuttle N, Sengupta R, Piccirilli JA. The Mechanism of Peptidyl Transfer Catalysis by the Ribosome. Annu Rev Biochem 2011; 80:527-55. [DOI: 10.1146/annurev-biochem-082108-165150] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Nikolai Suslov
- Department of Biochemistry and Molecular Biology, Chicago, Illinois 60637
| | - Nicole Tuttle
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637;
| | - Raghuvir Sengupta
- Department of Biochemistry, Stanford University, Stanford, California 94305
| | - Joseph Anthony Piccirilli
- Department of Biochemistry and Molecular Biology, Chicago, Illinois 60637
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637;
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36
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Liljas A. The ribosome story: An overview of structural studies of protein synthesis on the ribosome. CRYSTALLOGR REV 2011. [DOI: 10.1080/0889311x.2011.587812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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37
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Krishnakumar KS, Michel BY, Nguyen-Trung NQ, Fenet B, Strazewski P. Intrinsic pKa values of 3′-N-α-l-aminoacyl-3′-aminodeoxyadenosines determined by pH dependent 1H NMR in H2O. Chem Commun (Camb) 2011; 47:3290-2. [DOI: 10.1039/c0cc05136e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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38
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pH-sensitivity of the ribosomal peptidyl transfer reaction dependent on the identity of the A-site aminoacyl-tRNA. Proc Natl Acad Sci U S A 2010; 108:79-84. [PMID: 21169502 DOI: 10.1073/pnas.1012612107] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We studied the pH-dependence of ribosome catalyzed peptidyl transfer from fMet-tRNA(fMet) to the aa-tRNAs Phe-tRNA(Phe), Ala-tRNA(Ala), Gly-tRNA(Gly), Pro-tRNA(Pro), Asn-tRNA(Asn), and Ile-tRNA(Ile), selected to cover a large range of intrinsic pK(a)-values for the α-amino group of their amino acids. The peptidyl transfer rates were different at pH 7.5 and displayed different pH-dependence, quantified as the pH-value, pK(a)(obs), at which the rate was half maximal. The pK(a)(obs)-values were downshifted relative to the intrinsic pK(a)-value of aa-tRNAs in bulk solution. Gly-tRNA(Gly) had the smallest downshift, while Ile-tRNA(Ile) and Ala-tRNA(Ala) had the largest downshifts. These downshifts correlate strongly with molecular dynamics (MD) estimates of the downshifts in pK(a)-values of these aa-tRNAs upon A-site binding. Our data show the chemistry of peptide bond formation to be rate limiting for peptidyl transfer at pH 7.5 in the Gly and Pro cases and indicate rate limiting chemistry for all six aa-tRNAs.
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39
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Validating a new proton shuttle reaction pathway for formation of the peptide bond in ribosomes: A theoretical investigation. Chem Phys Lett 2010. [DOI: 10.1016/j.cplett.2010.10.048] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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40
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Rangelov MA, Petrova GP, Yomtova VM, Vayssilov GN. Catalytic Role of Vicinal OH in Ester Aminolysis: Proton Shuttle versus Hydrogen Bond Stabilization. J Org Chem 2010; 75:6782-92. [DOI: 10.1021/jo100886p] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Miroslav A. Rangelov
- Laboratory of BioCatalysis, Institute of Organic Chemistry, Bulgarian Academy of Sciences, Str. Acad. G. Bontchev, Bl. 9, 1113 Sofia, Bulgaria
| | - Galina P. Petrova
- Faculty of Chemistry, University of Sofia, Boulevard James Bouchier 1, 1164 Sofia, Bulgaria
| | - Vihra M. Yomtova
- Laboratory of BioCatalysis, Institute of Organic Chemistry, Bulgarian Academy of Sciences, Str. Acad. G. Bontchev, Bl. 9, 1113 Sofia, Bulgaria
| | - Georgi N. Vayssilov
- Faculty of Chemistry, University of Sofia, Boulevard James Bouchier 1, 1164 Sofia, Bulgaria
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41
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Yonath A. Winterschlafende Bären, Antibiotika und die Evolution des Ribosoms (Nobel-Aufsatz). Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201001297] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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42
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Yonath A. Hibernating Bears, Antibiotics, and the Evolving Ribosome (Nobel Lecture). Angew Chem Int Ed Engl 2010; 49:4341-54. [DOI: 10.1002/anie.201001297] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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43
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Hagiwara Y, Field MJ, Nureki O, Tateno M. Editing mechanism of aminoacyl-tRNA synthetases operates by a hybrid ribozyme/protein catalyst. J Am Chem Soc 2010; 132:2751-8. [PMID: 20136139 DOI: 10.1021/ja9095208] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Aminoacyl-tRNA synthetases (aaRSs) are critical for the translational process, catalyzing the attachment of specific amino acids to their cognate tRNAs. To ensure formation of the correct aminoacyl-tRNA, and thereby enhance the reliability of translation, several aaRSs have an editing capability that hinders formation of misaminoacylated tRNAs. We investigated theoretically the mechanism of the editing reaction for a class I enzyme, leucyl-tRNA synthetase (LeuRS), complexed with a misaminoacylated tRNA(Leu), employing ab initio hybrid quantum mechanical/molecular mechanical potentials in conjunction with molecular dynamics simulations. It is shown that the water molecule that acts as the nucleophile in the editing reaction is activated by a 3'-hydroxyl group at the 3'-end of tRNA(Leu) and that the O2' atom of the leaving group of the substrate is capped by one of the water's hydrogen atoms. Thus, it is shown that editing is a self-cleavage reaction of the tRNA and so it is the tRNA, and not the protein, that drives the reaction. The protein does, however, have an important stabilizing effect on some high-energy intermediates along the reaction path, which is more efficient than the ribozyme would be alone. This indicates that editing is achieved by a novel "hybrid ribozyme/protein catalyst". Analysis of existing experimental data and additional modeling shows that this ribozymal mechanism appears to be widespread, occurring in the ribosome as well as in other aaRSs. It also suggests transitional forms that could have played an important role in the RNA world hypothesis for the origin of life.
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Affiliation(s)
- Yohsuke Hagiwara
- Center for Computational Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba Science City, Ibaraki 305-8577, Japan
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44
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Hiller DA, Zhong M, Singh V, Strobel SA. Transition states of uncatalyzed hydrolysis and aminolysis reactions of a ribosomal P-site substrate determined by kinetic isotope effects. Biochemistry 2010; 49:3868-78. [PMID: 20359191 PMCID: PMC2864349 DOI: 10.1021/bi901458x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The ester bond of peptidyl-tRNA undergoes nucleophilic attack in solution and when catalyzed by the ribosome. To characterize the uncatalyzed hydrolysis reaction, a model of peptide release, the transition state structure for hydrolysis of a peptidyl-tRNA mimic was determined. Kinetic isotope effects were measured at several atoms that potentially undergo a change in bonding in the transition state. Large kinetic isotope effects of carbonyl (18)O and alpha-deuterium substitutions on uncatalyzed hydrolysis indicate the transition state is nearly tetrahedral. Kinetic isotope effects were also measured for aminolysis by hydroxylamine to study a reaction similar to the formation of a peptide bond. In contrast to hydrolysis, the large leaving group (18)O isotope effect indicates the C-O3' bond has undergone significant scission in the transition state. The smaller carbonyl (18)O and alpha-deuterium effects are consistent with a later transition state. The assay developed here can also be used to measure isotope effects for the ribosome-catalyzed reactions. These uncatalyzed reactions serve as a basis for determining what aspects of the transition states are stabilized by the ribosome to achieve a rate enhancement.
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Affiliation(s)
- David A Hiller
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven CT 06511 USA
| | | | - Vipender Singh
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven CT 06511 USA
| | - Scott A Strobel
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven CT 06511 USA
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45
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Kästner J, Sherwood P. The ribosome catalyzes peptide bond formation by providing high ionic strength. Mol Phys 2010. [DOI: 10.1080/00268970903446764] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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46
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The transition state for peptide bond formation reveals the ribosome as a water trap. Proc Natl Acad Sci U S A 2010; 107:1888-93. [PMID: 20080677 DOI: 10.1073/pnas.0914192107] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recent progress in elucidating the peptide bond formation process on the ribosome has led to notion of a proton shuttle mechanism where the 2'-hydroxyl group of the P-site tRNA plays a key role in mediating proton transfer between the nucleophile and leaving group, whereas ribosomal groups do not actively participate in the reaction. Despite these advances, the detailed nature of the transition state for peptidyl transfer and the role of several trapped water molecules in the peptidyl transferase center remain major open questions. Here, we employ high-level quantum chemical ab initio calculations to locate and characterize global transition states for the reaction, described by a molecular model encompassing all the key elements of the reaction center. The calculated activation enthalpy as well as structures are in excellent agreement with experimental data and point to feasibility of an eight-membered "double proton shuttle" mechanism in which an auxiliary water molecule, observed both in computer simulations and crystal structures, actively participates. A second conserved water molecule is found to be of key importance for stabilizing developing negative charge on the substrate oxyanion and its presence is catalytically favorable both in terms of activation enthalpy and entropy. Transition states calculated both for six- and eight-membered mechanisms are invariably late and do not involve significant charge development on the attacking amino group. Predicted kinetic isotope effects consistent with this picture are similar to those observed for uncatalyzed ester aminolysis reactions in solution.
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47
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Francklyn CS, Minajigi A. tRNA as an active chemical scaffold for diverse chemical transformations. FEBS Lett 2009; 584:366-75. [PMID: 19925795 DOI: 10.1016/j.febslet.2009.11.045] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Revised: 11/11/2009] [Accepted: 11/11/2009] [Indexed: 10/20/2022]
Abstract
During protein synthesis, tRNA serves as the intermediary between cognate amino acids and their corresponding RNA trinucleotide codons. Aminoacyl-tRNA is also a biosynthetic precursor and amino acid donor for other macromolecules. AA-tRNAs allow transformations of acidic amino acids into their amide-containing counterparts, and seryl-tRNA(Ser) donates serine for antibiotic synthesis. Aminoacyl-tRNA is also used to cross-link peptidoglycan, to lysinylate the lipid bilayer, and to allow proteolytic turnover via the N-end rule. These alternative functions may signal the use of RNA in early evolution as both a biological scaffold and a catalyst to achieve a wide variety of chemical transformations.
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Affiliation(s)
- Christopher S Francklyn
- Cell and Molecular Biology Program, University of Vermont, Burlington, VT 05405, United States.
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48
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Trobro S, Åqvist J. Mechanism of the Translation Termination Reaction on the Ribosome. Biochemistry 2009; 48:11296-303. [DOI: 10.1021/bi9017297] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Stefan Trobro
- Department of Cell and Molecular Biology, Uppsala University, Biomedical Center, Box 596, SE-751 24 Uppsala, Sweden
| | - Johan Åqvist
- Department of Cell and Molecular Biology, Uppsala University, Biomedical Center, Box 596, SE-751 24 Uppsala, Sweden
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49
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Banáš P, Jurečka P, Walter NG, Šponer J, Otyepka M. Theoretical studies of RNA catalysis: hybrid QM/MM methods and their comparison with MD and QM. Methods 2009; 49:202-16. [PMID: 19398008 PMCID: PMC2753711 DOI: 10.1016/j.ymeth.2009.04.007] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2009] [Revised: 04/07/2009] [Accepted: 04/07/2009] [Indexed: 11/28/2022] Open
Abstract
Hybrid QM/MM methods combine the rigor of quantum mechanical (QM) calculations with the low computational cost of empirical molecular mechanical (MM) treatment allowing to capture dynamic properties to probe critical atomistic details of enzyme reactions. Catalysis by RNA enzymes (ribozymes) has only recently begun to be addressed with QM/MM approaches and is thus still a field under development. This review surveys methodology as well as recent advances in QM/MM applications to RNA mechanisms, including those of the HDV, hairpin, and hammerhead ribozymes, as well as the ribosome. We compare and correlate QM/MM results with those from QM and/or molecular dynamics (MD) simulations, and discuss scope and limitations with a critical eye on current shortcomings in available methodologies and computer resources. We thus hope to foster mutual appreciation and facilitate collaboration between experimentalists and theorists to jointly advance our understanding of RNA catalysis at an atomistic level.
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Affiliation(s)
- Pavel Banáš
- Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, tr. Svobody 26, 771 46 Olomouc, Czech Republic
| | - Petr Jurečka
- Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, tr. Svobody 26, 771 46 Olomouc, Czech Republic
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno, Czech Republic
| | - Nils G. Walter
- Department of Chemistry, Single Molecule Analysis Group, University of Michigan, 930 N. University Ave., Ann Arbor, MI 48109-1055, USA
| | - Jiří Šponer
- Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, tr. Svobody 26, 771 46 Olomouc, Czech Republic
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno, Czech Republic
| | - Michal Otyepka
- Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, tr. Svobody 26, 771 46 Olomouc, Czech Republic
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno, Czech Republic
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50
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Michel BY, Strazewski P. Total syntheses of a conformationally locked North-type methanocarba puromycin analogue and a dinucleotide derivative. Chemistry 2009; 15:6244-57. [PMID: 19441002 DOI: 10.1002/chem.200802629] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
An original synthetic approach for the first synthesis of an enantiopure methanocarba puromycin (3'-alpha-aminoacylamino-3'-deoxyadenosine) analogue and its cytidine dinucleotide derivative is described. Each compound is conformationally locked in a North-type pucker and exhibits both a pseudoaxial hydroxy group and a pseudoequatorial aminoacyl group. The syntheses were accomplished from D-ribose in 18 and 19 steps, respectively, with key steps being a ring-closing metathesis, a Luche reduction, a Simmons-Smith cyclopropanation, a Mitsunobu coupling, a Mattocks bromoacetylation, a regioselective and a stereoselective nucleophilic substitution, a chemoselective phosphoramidite coupling and a Staudinger-Vilarrasa coupling. Both molecules are being tested for peptidyl transfer efficiency in ribosomes for comparison with the peptidyl transfer kinetics of natural puromycin and other natural and synthetic ribosomal A site substrates.
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Affiliation(s)
- Benoît Y Michel
- UMR 5246, CNRS, Laboratoire de Synthèse de Biomolécules, Université Claude Bernard Lyon 1, Villeurbanne, Université de Lyon, 69622 Lyon, France
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