1
|
Xu P, Mou X, Guo Q, Fu T, Ren H, Wang G, Li Y, Li G. Coarse-grained molecular dynamics study based on TorchMD. CHINESE J CHEM PHYS 2021. [DOI: 10.1063/1674-0068/cjcp2110218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Peijun Xu
- Liaoning Normal University, Dalian 116029, China
| | - Xiaohong Mou
- Liaoning Normal University, Dalian 116029, China
| | - Qiuhan Guo
- Liaoning Normal University, Dalian 116029, China
| | - Ting Fu
- Pharmacy Department of Affiliated Zhongshan Hospital of Dalian University, Dalian 116001, China
| | - Hong Ren
- Department of Ophthalmology Aerospace Center Hospital, Beijing 100049, China
| | - Guiyan Wang
- Dalian Ocean University, Dalian 116029, China
| | - Yan Li
- Dalian Institute of Chemical Physics, State Key Laboratory of Molecular Reaction Dynamics, Dalian 116023, China
| | - Guohui Li
- Dalian Institute of Chemical Physics, State Key Laboratory of Molecular Reaction Dynamics, Dalian 116023, China
| |
Collapse
|
2
|
Veenis AJ, Li P, Soudackov AV, Hammes-Schiffer S, Bevilacqua PC. Investigation of the p Ka of the Nucleophilic O2' of the Hairpin Ribozyme. J Phys Chem B 2021; 125:11869-11883. [PMID: 34695361 DOI: 10.1021/acs.jpcb.1c06546] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Small ribozymes cleave their RNA phosphodiester backbone by catalyzing a transphosphorylation reaction wherein a specific O2' functions as the nucleophile. While deprotonation of this alcohol through its acidification would increase its nucleophilicity, little is known about the pKa of this O2' in small ribozymes, in part because high pKa's are not readily accessible experimentally. Herein, we turn to molecular dynamics to calculate the pKa of the nucleophilic O2' in the hairpin ribozyme and to study interactions within the active site that may impact its value. We estimate the pKa of the nucleophilic O2' in the wild-type hairpin ribozyme to be 18.5 ± 0.8, which is higher than the reference compound, and identify a correlation between proper positioning of the O2' for nucleophilic attack and elevation of its pKa. We find that monovalent ions may play a role in depression of the O2' pKa, while the exocyclic amine appears to be important for organizing the ribozyme active site. Overall, this study suggests that the pKa of the O2' is raised in the ground state and lowers during the course of the reaction owing to positioning and metal ion interactions.
Collapse
Affiliation(s)
| | - Pengfei Li
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States.,Department of Chemistry and Biochemistry, Loyola University Chicago, Chicago, Illinois 60660, United States
| | - Alexander V Soudackov
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | | | | |
Collapse
|
3
|
Manigrasso J, Marcia M, De Vivo M. Computer-aided design of RNA-targeted small molecules: A growing need in drug discovery. Chem 2021. [DOI: 10.1016/j.chempr.2021.05.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
4
|
Yoon S, Harris ME. Beyond the Plateau: pL Dependence of Proton Inventories as a Tool for Studying Ribozyme and Ribonuclease Catalysis. Biochemistry 2021; 60:2810-2823. [PMID: 34495648 DOI: 10.1021/acs.biochem.1c00489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Acid/base catalysis is an important catalytic strategy used by ribonucleases and ribozymes; however, understanding the number and identity of functional groups involved in proton transfer remains challenging. The proton inventory (PI) technique analyzes the dependence of the enzyme reaction rate on the ratio of D2O to H2O and can provide information about the number of exchangeable sites that produce isotope effects and their magnitude. The Gross-Butler (GB) equation is used to evaluate H/D fractionation factors from PI data typically collected under conditions (i.e., a "plateau" in the pH-rate profile) assuming minimal change in active site residue ionization. However, restricting PI analysis to these conditions is problematic for many ribonucleases, ribozymes, and their variants due to ambiguity in the roles of active site residues, the lack of a plateau within the accessible pL range, or cooperative interactions between active site functional groups undergoing ionization. Here, we extend the integration of species distributions for alternative enzyme states in noncooperative models of acid/base catalysis into the GB equation, first used by Bevilacqua and colleagues for the HDV ribozyme, to develop a general population-weighted GB equation that allows simulation and global fitting of the three-dimensional relationship of the D2O ratio (n) versus pL versus kn/k0. Simulations using the GPW-GB equation of PI results for RNase A, HDVrz, and VSrz illustrate that data obtained at multiple selected pL values across the pL-rate profile can assist in the planning and interpreting of solvent isotope effect experiments to distinguish alternative mechanistic models.
Collapse
Affiliation(s)
- Suhyun Yoon
- Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, United States
| | - Michael E Harris
- Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, United States
| |
Collapse
|
5
|
Yagi K, Ito S, Sugita Y. Exploring the Minimum-Energy Pathways and Free-Energy Profiles of Enzymatic Reactions with QM/MM Calculations. J Phys Chem B 2021; 125:4701-4713. [PMID: 33914537 PMCID: PMC10986901 DOI: 10.1021/acs.jpcb.1c01862] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Understanding molecular mechanisms of enzymatic reactions is of vital importance in biochemistry and biophysics. Here, we introduce new functions of hybrid quantum mechanical/molecular mechanical (QM/MM) calculations in the GENESIS program to compute the minimum-energy pathways (MEPs) and free-energy profiles of enzymatic reactions. For this purpose, an interface in GENESIS is developed to utilize a highly parallel electronic structure program, QSimulate-QM (https://qsimulate.com), calling it as a shared library from GENESIS. Second, algorithms to search the MEP are implemented, combining the string method (E et al. J. Chem. Phys. 2007, 126, 164103) with the energy minimization of the buffer MM region. The method implemented in GENESIS is applied to an enzyme, triosephosphate isomerase, which converts dihyroxyacetone phosphate to glyceraldehyde 3-phosphate in four proton-transfer processes. QM/MM-molecular dynamics simulations show performances of greater than 1 ns/day with the density functional tight binding (DFTB), and 10-30 ps/day with the hybrid density functional theory, B3LYP-D3. These performances allow us to compute not only MEP but also the potential of mean force (PMF) of the enzymatic reactions using the QM/MM calculations. The barrier height obtained as 13 kcal mol-1 with B3LYP-D3 in the QM/MM calculation is in agreement with the experimental results. The impact of conformational sampling in PMF calculations and the level of electronic structure calculations (DFTB vs B3LYP-D3) suggests reliable computational protocols for enzymatic reactions without high computational costs.
Collapse
Affiliation(s)
- Kiyoshi Yagi
- Theoretical
Molecular Science Laboratory, RIKEN Cluster
for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Shingo Ito
- Theoretical
Molecular Science Laboratory, RIKEN Cluster
for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Yuji Sugita
- Theoretical
Molecular Science Laboratory, RIKEN Cluster
for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Computational
Biophysics Research Team, RIKEN Center for
Computational Science, 7-1-26 minatojima-Minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
- Laboratory
for Biomolecular Function Simulation, RIKEN
Center for Biosystems Dynamics Research, 1-6-5 minatojima-Minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
| |
Collapse
|
6
|
Casalino L, Nierzwicki Ł, Jinek M, Palermo G. Catalytic Mechanism of Non-Target DNA Cleavage in CRISPR-Cas9 Revealed by Ab Initio Molecular Dynamics. ACS Catal 2020; 10:13596-13605. [PMID: 33520346 PMCID: PMC7842700 DOI: 10.1021/acscatal.0c03566] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
CRISPR-Cas9 is a cutting-edge genome editing technology, which uses the endonuclease Cas9 to introduce mutations at desired sites of the genome. This revolutionary tool is promising to treat a myriad of human genetic diseases. Nevertheless, the molecular basis of DNA cleavage, which is a fundamental step for genome editing, has not been established. Here, quantum-classical molecular dynamics (MD) and free energy methods are used to disclose the two-metal-dependent mechanism of phosphodiester bond cleavage in CRISPR-Cas9. Ab initio MD reveals a conformational rearrangement of the Mg2+-bound RuvC active site, which entails the relocation of H983 to act as a general base. Then, the DNA cleavage proceeds through a concerted associative pathway fundamentally assisted by the joint dynamics of the two Mg2+ ions. This clarifies previous controversial experimental evidence, which could not fully establish the catalytic role of the conserved H983 and the metal cluster conformation. The comparison with other two-metal-dependent enzymes supports the identified mechanism and suggests a common catalytic strategy for genome editing and recombination. Overall, the non-target DNA cleavage catalysis described here resolves a fundamental open question in the CRISPR-Cas9 biology and provides valuable insights for improving the catalytic efficiency and the metal-dependent function of the Cas9 enzyme, which are at the basis of the development of genome editing tools.
Collapse
Affiliation(s)
- Lorenzo Casalino
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, United States
| | - Łukasz Nierzwicki
- Department of Bioengineering, University of California Riverside, Riverside, California 92521, United States
| | - Martin Jinek
- Department of Biochemistry, University of Zürich, CH-8057 Zürich, Switzerland
| | - Giulia Palermo
- Department of Bioengineering and Department of Chemistry, University of California Riverside, Riverside, California 92521, United States
| |
Collapse
|
7
|
Borišek J, Magistrato A. All-Atom Simulations Decrypt the Molecular Terms of RNA Catalysis in the Exon-Ligation Step of the Spliceosome. ACS Catal 2020. [DOI: 10.1021/acscatal.0c00390] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jure Borišek
- National Institute of Chemistry, Hajdrihova 19, 1001 Ljubljana, Slovenia
| | - Alessandra Magistrato
- CNR-IOM-Democritos national Simulation Center c/o SISSA, Via Bonomea 265, 34136 Trieste, Italy
| |
Collapse
|
8
|
Kumar N, Marx D. Mechanistic role of nucleobases in self-cleavage catalysis of hairpin ribozyme at ambient versus high-pressure conditions. Phys Chem Chem Phys 2019; 20:20886-20898. [PMID: 30067263 DOI: 10.1039/c8cp03142h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Ribozymes catalyze the site-specific self-cleavage of intramolecular phosphodiester bonds. Initially thought to act as metalloenzymes, they are now known to be functional even in the absence of divalent metal ions and specific nucleobases directly participate in the self-cleavage reaction. Here, we use extensive replica exchange molecular dynamics simulations to probe the precise mechanistic role of nucleobases by simulating precatalytic reactant and active precursor states of a hairpin ribozyme along its reaction path at ambient as well as high-pressure conditions. The results provide novel key insights into the self-cleavage of ribozymes. We find that deprotonation of the hydroxyl group is crucial and might be the penultimate step to the self-cleavage. The G8 nucleobase is found to stabilize the activated precursor into inline arrangement for facile nucleophilic attack of the scissile phosphate only after deprotonation of the hydroxyl group. The protonated A38 nucleobase, in contrast, mainly acts a proton donor to the O5'-oxygen leaving group that eventually leads to the self-cleavage. Indeed, systematic high-pressure simulations of catalytically relevant states confirm these findings and, moreover, provide support to the role of ribozymes as piezophilic biocatalysts with regard to their relevance in early life under extreme conditions in the realm of RNA world hypothesis.
Collapse
Affiliation(s)
- Narendra Kumar
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany.
| | | |
Collapse
|
9
|
Dans PD, Gallego D, Balaceanu A, Darré L, Gómez H, Orozco M. Modeling, Simulations, and Bioinformatics at the Service of RNA Structure. Chem 2019. [DOI: 10.1016/j.chempr.2018.09.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
10
|
Tuñón I, Williams IH. The transition state and cognate concepts. ADVANCES IN PHYSICAL ORGANIC CHEMISTRY 2019. [DOI: 10.1016/bs.apoc.2019.09.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
11
|
Manna RN, Malakar T, Jana B, Paul A. Unraveling the Crucial Role of Single Active Water Molecule in the Oxidative Cleavage of Aliphatic C–C Bond of 2,4′-Dihydroxyacetophenone Catalyzed by 2,4′-Dihydroxyacetophenone Dioxygenase Enzyme: A Quantum Mechanics/Molecular Mechanics Investigation. ACS Catal 2018. [DOI: 10.1021/acscatal.8b03201] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Rabindra Nath Manna
- Department of Physical Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
| | - Tanmay Malakar
- Raman Center for Atomic, Molecular, and Optical Science, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Biman Jana
- Department of Physical Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
| | - Ankan Paul
- Raman Center for Atomic, Molecular, and Optical Science, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
| |
Collapse
|
12
|
Acosta-Silva C, Bertran J, Branchadell V, Oliva A. Phosphoryl-Transfer Reaction in RNA under Alkaline Conditions. Chemistry 2018; 24:13565-13572. [PMID: 29943454 DOI: 10.1002/chem.201802332] [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: 05/09/2018] [Revised: 06/20/2018] [Indexed: 11/09/2022]
Abstract
The phosphoryl-transfer reaction in RNA under alkaline conditions by exploring the influence of several solvents theoretically was studied. The calculations were carried out by using the M06-2X functional and the solvents were taken as a continuum by using the solvent model density (SMD) method. The main findings show that the O2'-P-O5' angle in the reactants, the free activation energies, and the reaction mechanism are clearly dependent on the dielectric constant of the environment, thus showing that the electrostatic term is the determining factor for this chemical system with two negative charges. Our study seems to indicate that water, the solvent with the greatest dielectric constant, would be the solvent that increases the reaction rate the most. As this outcome was not the case in enzymatic catalysis, one has to conclude that, in the case of proteins as well as for ribozymes, the enzymatic catalysis is not mainly due to the solvent reaction field, but to local electrical fields as a result of enzyme preorganization.
Collapse
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
| |
Collapse
|
13
|
Krepl M, Vögele J, Kruse H, Duchardt-Ferner E, Wöhnert J, Sponer J. An intricate balance of hydrogen bonding, ion atmosphere and dynamics facilitates a seamless uracil to cytosine substitution in the U-turn of the neomycin-sensing riboswitch. Nucleic Acids Res 2018; 46:6528-6543. [PMID: 29893898 PMCID: PMC6061696 DOI: 10.1093/nar/gky490] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 05/23/2018] [Indexed: 01/04/2023] Open
Abstract
The neomycin sensing riboswitch is the smallest biologically functional RNA riboswitch, forming a hairpin capped with a U-turn loop-a well-known RNA motif containing a conserved uracil. It was shown previously that a U→C substitution of the eponymous conserved uracil does not alter the riboswitch structure due to C protonation at N3. Furthermore, cytosine is evolutionary permitted to replace uracil in other U-turns. Here, we use molecular dynamics simulations to study the molecular basis of this substitution in the neomycin sensing riboswitch and show that a structure-stabilizing monovalent cation-binding site in the wild-type RNA is the main reason for its negligible structural effect. We then use NMR spectroscopy to confirm the existence of this cation-binding site and to demonstrate its effects on RNA stability. Lastly, using quantum chemical calculations, we show that the cation-binding site is altering the electronic environment of the wild-type U-turn so that it is more similar to the cytosine mutant. The study reveals an amazingly complex and delicate interplay between various energy contributions shaping up the 3D structure and evolution of nucleic acids.
Collapse
Affiliation(s)
- Miroslav Krepl
- Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, 612 65 Brno, Czech Republic
| | - Jennifer Vögele
- Institute of Molecular Biosciences and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Holger Kruse
- Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, 612 65 Brno, Czech Republic
| | - Elke Duchardt-Ferner
- Institute of Molecular Biosciences and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Jens Wöhnert
- Institute of Molecular Biosciences and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Jiri Sponer
- Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, 612 65 Brno, Czech Republic
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, 17. listopadu 12, 771 46 Olomouc, Czech Republic
| |
Collapse
|
14
|
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.
Collapse
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
| |
Collapse
|
15
|
Cepeda-Plaza M, McGhee CE, Lu Y. Evidence of a General Acid-Base Catalysis Mechanism in the 8-17 DNAzyme. Biochemistry 2018; 57:1517-1522. [PMID: 29389111 PMCID: PMC5879137 DOI: 10.1021/acs.biochem.7b01096] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
DNAzymes are catalytic DNA molecules that can perform a variety of reactions. Although advances have been made in obtaining DNAzymes via in vitro selection and many of them have been developed into sensors and imaging agents for metal ions, bacteria, and other molecules, the structural features responsible for these enzymatic reactions are still not well understood. Previous studies of the 8-17 DNAzyme have suggested conserved guanines close to the phosphodiester transfer site may play a role in the catalytic reaction. To identify the specific guanine and functional group of the guanine responsible for the reaction, we herein report the effects of replacing G1.1 and G14 (G; p Ka,N1 = 9.4) with analogues with a different p Ka at the N1 position, such as inosine (G14I; p Ka,N1 = 8.7), 2,6-diaminopurine (G14diAP; p Ka,N1 = 5.6), and 2-aminopurine (G14AP; p Ka,N1 = 3.8) on pH-dependent reaction rates. A comparison of the pH dependence of the reaction rates of these DNAzymes demonstrated that G14 in the bulge loop next to the cleavage site, is involved in proton transfer at the catalytic site. In contrast, we did not find any evidence of G1.1 being involved in acid-base catalysis. These results support general acid-base catalysis as a feasible strategy used in DNA catalysis, as in RNA and protein enzymes.
Collapse
Affiliation(s)
- Marjorie Cepeda-Plaza
- Department of Chemical Sciences, School of Exact Sciences, Universidad Andres Bello, República 275, Santiago, Chile
| | - Claire E. McGhee
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, Illinois 61801
| | - Yi Lu
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, Illinois 61801
| |
Collapse
|
16
|
Šponer JE, Szabla R, Góra RW, Saitta AM, Pietrucci F, Saija F, Di Mauro E, Saladino R, Ferus M, Civiš S, Šponer J. Prebiotic synthesis of nucleic acids and their building blocks at the atomic level - merging models and mechanisms from advanced computations and experiments. Phys Chem Chem Phys 2018; 18:20047-66. [PMID: 27136968 DOI: 10.1039/c6cp00670a] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The origin of life on Earth is one of the most fascinating questions of contemporary science. Extensive research in the past decades furnished diverse experimental proposals for the emergence of first informational polymers that could form the basis of the early terrestrial life. Side by side with the experiments, the fast development of modern computational chemistry methods during the last 20 years facilitated the use of in silico modelling tools to complement the experiments. Modern computations can provide unique atomic-level insights into the structural and electronic aspects as well as the energetics of key prebiotic chemical reactions. Many of these insights are not directly obtainable from the experimental techniques and the computations are thus becoming indispensable for proper interpretation of many experiments and for qualified predictions. This review illustrates the synergy between experiment and theory in the origin of life research focusing on the prebiotic synthesis of various nucleic acid building blocks and on the self-assembly of nucleotides leading to the first functional oligonucleotides.
Collapse
Affiliation(s)
- Judit E Šponer
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, CZ-612 65 Brno, Czech Republic. and CEITEC - Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, CZ-62500 Brno, Czech Republic
| | - Rafał Szabla
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, CZ-612 65 Brno, Czech Republic.
| | - Robert W Góra
- Theoretical Chemistry Group, Institute of Physical and Theoretical Chemistry, Wrocław University of Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
| | - A Marco Saitta
- Sorbonne Universités, Université Pierre et Marie Curie Paris 6, CNRS, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Muséum National d'Histoire Naturelle, Institut de Recherche pour le Développement, UMR 7590, F-75005 Paris, France
| | - Fabio Pietrucci
- Sorbonne Universités, Université Pierre et Marie Curie Paris 6, CNRS, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Muséum National d'Histoire Naturelle, Institut de Recherche pour le Développement, UMR 7590, F-75005 Paris, France
| | - Franz Saija
- CNR-IPCF, Viale Ferdinando Stagno d'Alcontres 37, 98158 Messina, Italy
| | - Ernesto Di Mauro
- Dipartimento di Biologia e Biotecnologie "Charles Darwin", "Sapienza" Università di Roma, Piazzale Aldo Moro 5, Rome 00185, Italy
| | - Raffaele Saladino
- Dipartimento di Scienze Ecologiche e Biologiche Università della Tuscia, Via San Camillo De Lellis, 01100 Viterbo, Italy
| | - Martin Ferus
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, CZ-182 23 Prague 8, Czech Republic
| | - Svatopluk Civiš
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, CZ-182 23 Prague 8, Czech Republic
| | - Jiří Šponer
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, CZ-612 65 Brno, Czech Republic. and CEITEC - Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, CZ-62500 Brno, Czech Republic
| |
Collapse
|
17
|
Mlýnský V, Bussi G. Exploring RNA structure and dynamics through enhanced sampling simulations. Curr Opin Struct Biol 2018; 49:63-71. [PMID: 29414513 DOI: 10.1016/j.sbi.2018.01.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 12/20/2017] [Accepted: 01/02/2018] [Indexed: 01/23/2023]
Abstract
RNA function is intimately related to its structural dynamics. Molecular dynamics simulations are useful for exploring biomolecular flexibility but are severely limited by the accessible timescale. Enhanced sampling methods allow this timescale to be effectively extended in order to probe biologically relevant conformational changes and chemical reactions. Here, we review the role of enhanced sampling techniques in the study of RNA systems. We discuss the challenges and promises associated with the application of these methods to force-field validation, exploration of conformational landscapes and ion/ligand-RNA interactions, as well as catalytic pathways. Important technical aspects of these methods, such as the choice of the biased collective variables and the analysis of multi-replica simulations, are examined in detail. Finally, a perspective on the role of these methods in the characterization of RNA dynamics is provided.
Collapse
Affiliation(s)
- Vojtěch Mlýnský
- Scuola Internazionale Superiore di Studi Avanzati, SISSA, via Bonomea 265, 34136 Trieste, Italy
| | - Giovanni Bussi
- Scuola Internazionale Superiore di Studi Avanzati, SISSA, via Bonomea 265, 34136 Trieste, Italy.
| |
Collapse
|
18
|
Seith DD, Bingaman JL, Veenis AJ, Button AC, Bevilacqua PC. Elucidation of Catalytic Strategies of Small Nucleolytic Ribozymes From Comparative Analysis of Active Sites. ACS Catal 2018; 8:314-327. [PMID: 32547833 PMCID: PMC7296830 DOI: 10.1021/acscatal.7b02976] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A number of small, self-cleaving ribozyme classes have been identified including the hammerhead, hairpin, hepatitis delta virus (HDV), Varkud satellite (VS), glmS, twister, hatchet, pistol, and twister sister ribozymes. Within the active sites of these ribozymes, myriad functional groups contribute to catalysis. There has been extensive structure-function analysis of individual ribozymes, but the extent to which catalytic devices are shared across different ribozyme classes is unclear. As such, emergent catalytic principles for ribozymes may await discovery. Identification of conserved catalytic devices can deepen our understanding of RNA catalysis specifically and of enzymic catalysis generally. To probe similarities and differences amongst ribozyme classes, active sites from more than 80 high-resolution crystal structures of self-cleaving ribozymes were compared computationally. We identify commonalities amongst ribozyme classes pertaining to four classic catalytic devices: deprotonation of the 2'OH nucleophile (γ), neutralization of the non-bridging oxygens of the scissile phosphate (β), neutralization of the O5' leaving group (δ), and in-line nucleophilic attack (α). In addition, we uncover conservation of two catalytic devices, each of which centers on the activation of the 2'OH nucleophile by a guanine: one to acidify the 2'OH by hydrogen bond donation to it (γ') and one to acidify the 2'OH by releasing it from non-productive interactions by competitive hydrogen bonding (γ''). Our findings reveal that the amidine functionalities of G, A, and C are especially important for these strategies, and help explain absence of U at ribozyme active sites. The identified γ' and γ'' catalytic strategies help unify the catalytic strategies shared amongst catalytic RNAs and may be important for large ribozymes, as well as protein enzymes that act on nucleic acids.
Collapse
Affiliation(s)
- Daniel D. Seith
- Department of Chemistry and Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802
- These two authors contributed equally to this work
| | - Jamie L. Bingaman
- Department of Chemistry and Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802
- These two authors contributed equally to this work
| | - Andrew J. Veenis
- Department of Chemistry and Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Aileen C. Button
- Department of Chemistry and Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802
- Department of Biochemistry, The University of Vermont, Burlington, Vermont 05405
| | - Philip C. Bevilacqua
- Department of Chemistry and Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802
| |
Collapse
|
19
|
Studying Parasite Gene Function and Interaction Through Ribozymes and Riboswitches Design Mechanism. Synth Biol (Oxf) 2018. [DOI: 10.1007/978-981-10-8693-9_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
|
20
|
Giese TJ, York DM. Quantum mechanical force fields for condensed phase molecular simulations. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:383002. [PMID: 28817382 PMCID: PMC5821073 DOI: 10.1088/1361-648x/aa7c5c] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Molecular simulations are powerful tools for providing atomic-level details into complex chemical and physical processes that occur in the condensed phase. For strongly interacting systems where quantum many-body effects are known to play an important role, density-functional methods are often used to provide the model with the potential energy used to drive dynamics. These methods, however, suffer from two major drawbacks. First, they are often too computationally intensive to practically apply to large systems over long time scales, limiting their scope of application. Second, there remain challenges for these models to obtain the necessary level of accuracy for weak non-bonded interactions to obtain quantitative accuracy for a wide range of condensed phase properties. Quantum mechanical force fields (QMFFs) provide a potential solution to both of these limitations. In this review, we address recent advances in the development of QMFFs for condensed phase simulations. In particular, we examine the development of QMFF models using both approximate and ab initio density-functional models, the treatment of short-ranged non-bonded and long-ranged electrostatic interactions, and stability issues in molecular dynamics calculations. Example calculations are provided for crystalline systems, liquid water, and ionic liquids. We conclude with a perspective for emerging challenges and future research directions.
Collapse
|
21
|
Abstract
Approaches to determine chlorine kinetic isotope effects (Cl-KIEs) on enzymatic dehalogenations are discussed and illustrated by representative examples. Three aspects are considered. First methodology for experimental measurement of Cl-KIEs, with stress being on FAB-IRMS technique developed in our laboratory, is described. Subsequently, we concentrate our discussion on the consequences of reaction complexity in the interpretation of experimental values, a problem especially important in cases of polychlorinated reactants. The most fruitful studies of enzymatic dehalogenations by Cl-KIEs require their theoretical evaluation, hence the computational focus of the second part of this chapter.
Collapse
|
22
|
Huang M, Dissanayake T, Kuechler E, Radak BK, Lee TS, Giese TJ, York DM. A Multidimensional B-Spline Correction for Accurate Modeling Sugar Puckering in QM/MM Simulations. J Chem Theory Comput 2017; 13:3975-3984. [PMID: 28768099 PMCID: PMC5839098 DOI: 10.1021/acs.jctc.7b00161] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The computational efficiency of approximate quantum mechanical methods allows their use for the construction of multidimensional reaction free energy profiles. It has recently been demonstrated that quantum models based on the neglect of diatomic differential overlap (NNDO) approximation have difficulty modeling deoxyribose and ribose sugar ring puckers and thus limit their predictive value in the study of RNA and DNA systems. A method has been introduced in our previous work to improve the description of the sugar puckering conformational landscape that uses a multidimensional B-spline correction map (BMAP correction) for systems involving intrinsically coupled torsion angles. This method greatly improved the adiabatic potential energy surface profiles of DNA and RNA sugar rings relative to high-level ab initio methods even for highly problematic NDDO-based models. In the present work, a BMAP correction is developed, implemented, and tested in molecular dynamics simulations using the AM1/d-PhoT semiempirical Hamiltonian for biological phosphoryl transfer reactions. Results are presented for gas-phase adiabatic potential energy surfaces of RNA transesterification model reactions and condensed-phase QM/MM free energy surfaces for nonenzymatic and RNase A-catalyzed transesterification reactions. The results show that the BMAP correction is stable, efficient, and leads to improvement in both the potential energy and free energy profiles for the reactions studied, as compared with ab initio and experimental reference data. Exploration of the effect of the size of the quantum mechanical region indicates the best agreement with experimental reaction barriers occurs when the full CpA dinucleotide substrate is treated quantum mechanically with the sugar pucker correction.
Collapse
Affiliation(s)
- Ming Huang
- Center for Integrative Proteomics Research, Laboratory for Biomolecular Simulation Research and Department of Chemistry and Chemical Biology, Rutgers University, 174 Frelinghuysen Road, Piscataway, New Jersey 08854, United States
| | - Thakshila Dissanayake
- Center for Integrative Proteomics Research, Laboratory for Biomolecular Simulation Research and Department of Chemistry and Chemical Biology, Rutgers University, 174 Frelinghuysen Road, Piscataway, New Jersey 08854, United States
| | - Erich Kuechler
- Center for Integrative Proteomics Research, Laboratory for Biomolecular Simulation Research and Department of Chemistry and Chemical Biology, Rutgers University, 174 Frelinghuysen Road, Piscataway, New Jersey 08854, United States
| | - Brian K. Radak
- Center for Integrative Proteomics Research, Laboratory for Biomolecular Simulation Research and Department of Chemistry and Chemical Biology, Rutgers University, 174 Frelinghuysen Road, Piscataway, New Jersey 08854, United States
| | - Tai-Sung Lee
- Center for Integrative Proteomics Research, Laboratory for Biomolecular Simulation Research and Department of Chemistry and Chemical Biology, Rutgers University, 174 Frelinghuysen Road, Piscataway, New Jersey 08854, United States
| | - Timothy J. Giese
- Center for Integrative Proteomics Research, Laboratory for Biomolecular Simulation Research and Department of Chemistry and Chemical Biology, Rutgers University, 174 Frelinghuysen Road, Piscataway, New Jersey 08854, United States
| | - Darrin M. York
- Center for Integrative Proteomics Research, Laboratory for Biomolecular Simulation Research and Department of Chemistry and Chemical Biology, Rutgers University, 174 Frelinghuysen Road, Piscataway, New Jersey 08854, United States
| |
Collapse
|
23
|
Zinovjev K, Tuñón I. Reaction coordinates and transition states in enzymatic catalysis. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2017. [DOI: 10.1002/wcms.1329] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Kirill Zinovjev
- Departament de Química FísicaUniversitat de València Valencia Spain
| | - Iñaki Tuñón
- Departament de Química FísicaUniversitat de València Valencia Spain
| |
Collapse
|
24
|
Panja S, Hua B, Zegarra D, Ha T, Woodson SA. Metals induce transient folding and activation of the twister ribozyme. Nat Chem Biol 2017; 13:1109-1114. [PMID: 28825710 PMCID: PMC5605428 DOI: 10.1038/nchembio.2459] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 07/18/2017] [Indexed: 11/15/2022]
Abstract
Twister is a small ribozyme present in almost all kingdoms of life that rapidly self-cleaves in variety of divalent metal ions. We used activity assays, bulk FRET and single-molecule FRET (smFRET) to understand how different metal ions promote folding and self-cleavage of the Oryza sativa Twister ribozyme. Although most ribozymes require additional Mg2+ for catalysis, Twister inverts this expectation, requiring 20–30 times less Mg2+ to self-cleave than to fold. Transition metals such as Co2+, Ni2+ and Zn2+ activate Twister more efficiently than Mg2+ ions. Although Twister is fully active in ≤ 0.5 mM MgCl2, smFRET experiments showed that the ribozyme visits the folded state infrequently under these conditions. Comparison of folding and self-cleavage rates indicates that most folding events lead to catalysis, which correlates with metal bond strength. Thus, the robust activity of Twister reports on transient metal ion binding under physiological conditions.
Collapse
Affiliation(s)
- Subrata Panja
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland, USA
| | - Boyang Hua
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Diego Zegarra
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland, USA
| | - Taekjip Ha
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland, USA.,Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, Maryland, USA.,Howard Hughes Medical Institute, Baltimore, Maryland, USA
| | - Sarah A Woodson
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland, USA
| |
Collapse
|
25
|
Bingaman JL, Gonzalez IY, Wang B, Bevilacqua PC. Activation of the glmS Ribozyme Nucleophile via Overdetermined Hydrogen Bonding. Biochemistry 2017; 56:4313-4317. [DOI: 10.1021/acs.biochem.7b00662] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jamie L. Bingaman
- Department
of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center
for RNA Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Inanllely Y. Gonzalez
- Department
of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Bo Wang
- Department
of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Philip C. Bevilacqua
- Department
of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center
for RNA Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Department
of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| |
Collapse
|
26
|
Ganguly A, Luong TQ, Brylski O, Dirkmann M, Möller D, Ebbinghaus S, Schulz F, Winter R, Sanchez-Garcia E, Thiel W. Elucidation of the Catalytic Mechanism of a Miniature Zinc Finger Hydrolase. J Phys Chem B 2017. [DOI: 10.1021/acs.jpcb.7b05027] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Abir Ganguly
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim an der Ruhr, Germany
| | - Trung Quan Luong
- Fakultät
für Chemie und Chemische Biologie, Physikalische Chemie I, Technische Universität Dortmund, 44227 Dortmund, Germany
| | - Oliver Brylski
- Fakultät
für Chemie und Biochemie, Physikalische Chemie II, Ruhr-Universität Bochum, 44780, Bochum, Germany
| | - Michael Dirkmann
- Fakultät
für Chemie und Biochemie, Organische Chemie I, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - David Möller
- Fakultät
für Chemie und Biochemie, Organische Chemie I, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Simon Ebbinghaus
- Fakultät
für Chemie und Biochemie, Physikalische Chemie II, Ruhr-Universität Bochum, 44780, Bochum, Germany
| | - Frank Schulz
- Fakultät
für Chemie und Biochemie, Organische Chemie I, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Roland Winter
- Fakultät
für Chemie und Chemische Biologie, Physikalische Chemie I, Technische Universität Dortmund, 44227 Dortmund, Germany
| | | | - Walter Thiel
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim an der Ruhr, Germany
| |
Collapse
|
27
|
Chen H, Giese TJ, Golden BL, York DM. Divalent Metal Ion Activation of a Guanine General Base in the Hammerhead Ribozyme: Insights from Molecular Simulations. Biochemistry 2017; 56:2985-2994. [PMID: 28530384 DOI: 10.1021/acs.biochem.6b01192] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The hammerhead ribozyme is a well-studied nucleolytic ribozyme that catalyzes the self-cleavage of the RNA phosphodiester backbone. Despite experimental and theoretical efforts, key questions remain about details of the mechanism with regard to the activation of the nucleophile by the putative general base guanine (G12). Straightforward interpretation of the measured activity-pH data implies the pKa value of the N1 position in the G12 nucleobase is significantly shifted by the ribozyme environment. Recent crystallographic and biochemical work has identified pH-dependent divalent metal ion binding at the N7/O6 position of G12, leading to the hypothesis that this binding mode could induce a pKa shift of G12 toward neutrality. We present computational results that support this hypothesis and provide a model that unifies the interpretation of available structural and biochemical data and paints a detailed mechanistic picture of the general base step of the reaction. Experimentally testable predictions are made for mutational and rescue effects on G12, which will give further insights into the catalytic mechanism. These results contribute to our growing knowledge of the potential roles of divalent metal ions in RNA catalysis.
Collapse
Affiliation(s)
- Haoyuan Chen
- Laboratory for Biomolecular Simulation Research, Center for Integrative Proteomics Research, and Department of Chemistry & Chemical Biology, Rutgers University , 174 Frelinghuysen Road, Piscataway, New Jersey 08854-8076, United States
| | - Timothy J Giese
- Laboratory for Biomolecular Simulation Research, Center for Integrative Proteomics Research, and Department of Chemistry & Chemical Biology, Rutgers University , 174 Frelinghuysen Road, Piscataway, New Jersey 08854-8076, United States
| | - Barbara L Golden
- Department of Biochemistry, Purdue University , West Lafayette, Indiana 47907, United States
| | - Darrin M York
- Laboratory for Biomolecular Simulation Research, Center for Integrative Proteomics Research, and Department of Chemistry & Chemical Biology, Rutgers University , 174 Frelinghuysen Road, Piscataway, New Jersey 08854-8076, United States
| |
Collapse
|
28
|
Frankel EA, Strulson CA, Keating CD, Bevilacqua PC. Cooperative Interactions in the Hammerhead Ribozyme Drive pK a Shifting of G12 and Its Stacked Base C17. Biochemistry 2017; 56:2537-2548. [PMID: 28485924 DOI: 10.1021/acs.biochem.7b00174] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
General acid-base catalysis is a key mechanistic strategy in protein and RNA enzymes. Ribozymes use hydrated metal ions, nucleobases, and organic cofactors to carry this out. In most small ribozymes, a guanosine is positioned to participate in proton transfer with the nucleophilic 2'-OH. The unshifted pKa values for nucleobases and solvated metal ions are far from neutrality, however, and thus nonideal for general acid-base catalysis. Herein, evidence is provided for cooperative interaction in the hammerhead ribozyme among the guanine that interacts with the nucleophilic 2'-OH, G12, the -1 nucleobase C17, and Mg2+ ions. We introduce global fitting for analyzing ribozyme rate-pH data parametric in Mg2+ concentration and benchmark this method on data from the hepatitis delta virus ribozyme. We then apply global fitting to new rate-pH data for the hammerhead ribozyme using a minimal three-dimensional, four-channel cooperative model. The value for the pKa of G12 that we obtain is channel-dependent and varies from 8.1 to 9.9, shifting closest toward neutrality in the presence of two cationic species: C17H+ and a Mg2+ ion. The value for the pKa of the -1 nucleotide, C17, is increased a remarkable 3.5-5 pKa units toward neutrality. Shifting of the pKa of C17 appears to be driven by an electrostatic sandwich of C17 between carbonyl groups of the 5'-neighboring U and of G12 and involves cation-π interactions. Rate-pH profiles reveal that the major reactive channel under biological Mg2+ and pH involves a cationic C17 rather than a second metal ion. Substitution of a cationic base for a metal underscores the versatility of RNA.
Collapse
Affiliation(s)
- Erica A Frankel
- Department of Chemistry, Pennsylvania State University , University Park, Pennsylvania 16802, United States.,Center for RNA Molecular Biology, Pennsylvania State University , University Park, Pennsylvania 16802, United States
| | - Christopher A Strulson
- Department of Chemistry, Pennsylvania State University , University Park, Pennsylvania 16802, United States.,Center for RNA Molecular Biology, Pennsylvania State University , University Park, Pennsylvania 16802, United States
| | - Christine D Keating
- Department of Chemistry, Pennsylvania State University , University Park, Pennsylvania 16802, United States
| | - Philip C Bevilacqua
- Department of Chemistry, Pennsylvania State University , University Park, Pennsylvania 16802, United States.,Center for RNA Molecular Biology, Pennsylvania State University , University Park, Pennsylvania 16802, United States.,Department of Biochemistry and Molecular Biology, Pennsylvania State University , University Park, Pennsylvania 16802, United States
| |
Collapse
|
29
|
Ganguly A, Boulanger E, Thiel W. Importance of MM Polarization in QM/MM Studies of Enzymatic Reactions: Assessment of the QM/MM Drude Oscillator Model. J Chem Theory Comput 2017; 13:2954-2961. [DOI: 10.1021/acs.jctc.7b00016] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Abir Ganguly
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Eliot Boulanger
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Walter Thiel
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| |
Collapse
|
30
|
Mlýnský V, Bussi G. Understanding in-line probing experiments by modeling cleavage of nonreactive RNA nucleotides. RNA (NEW YORK, N.Y.) 2017; 23:712-720. [PMID: 28202709 PMCID: PMC5393180 DOI: 10.1261/rna.060442.116] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 02/03/2017] [Indexed: 05/25/2023]
Abstract
Ribonucleic acid (RNA) is involved in many regulatory and catalytic processes in the cell. The function of any RNA molecule is intimately related with its structure. In-line probing experiments provide valuable structural data sets for a variety of RNAs and are used to characterize conformational changes in riboswitches. However, the structural determinants that lead to differential reactivities in unpaired nucleotides have not been investigated yet. In this work, we used a combination of theoretical approaches, i.e., classical molecular dynamics simulations, multiscale quantum mechanical/molecular mechanical calculations, and enhanced sampling techniques in order to compute and interpret the differential reactivity of individual residues in several RNA motifs, including members of the most important GNRA and UNCG tetraloop families. Simulations on the multinanosecond timescale are required to converge the related free-energy landscapes. The results for uGAAAg and cUUCGg tetraloops and double helices are compared with available data from in-line probing experiments and show that the introduced technique is able to distinguish between nucleotides of the uGAAAg tetraloop based on their structural predispositions toward phosphodiester backbone cleavage. For the cUUCGg tetraloop, more advanced ab initio calculations would be required. This study is the first attempt to computationally classify chemical probing experiments and paves the way for an identification of tertiary structures based on the measured reactivity of nonreactive nucleotides.
Collapse
Affiliation(s)
- Vojtěch Mlýnský
- Scuola Internazionale Superiore di Studi Avanzati (SISSA), 34136 Trieste, Italy
| | - Giovanni Bussi
- Scuola Internazionale Superiore di Studi Avanzati (SISSA), 34136 Trieste, Italy
| |
Collapse
|
31
|
Bingaman JL, Zhang S, Stevens DR, Yennawar NH, Hammes-Schiffer S, Bevilacqua PC. The GlcN6P cofactor plays multiple catalytic roles in the glmS ribozyme. Nat Chem Biol 2017; 13:439-445. [PMID: 28192411 PMCID: PMC5362308 DOI: 10.1038/nchembio.2300] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Accepted: 12/09/2016] [Indexed: 01/06/2023]
Abstract
RNA enzymes (ribozymes) have remarkably diverse biological roles despite having limited chemical diversity. Protein enzymes enhance their reactivity through recruitment of cofactors; likewise, the naturally occurring glmS ribozyme uses the glucosamine-6-phosphate (GlcN6P) organic cofactor for phosphodiester bond cleavage. Prior structural and biochemical studies have implicated GlcN6P as the general acid. Here we describe new catalytic roles of GlcN6P through experiments and calculations. Large stereospecific normal thio effects and a lack of metal-ion rescue in the holoribozyme indicate that nucleobases and the cofactor play direct chemical roles and align the active site for self-cleavage. Large stereospecific inverse thio effects in the aporibozyme suggest that the GlcN6P cofactor disrupts an inhibitory interaction of the nucleophile. Strong metal-ion rescue in the aporibozyme reveals that this cofactor also provides electrostatic stabilization. Ribozyme organic cofactors thus perform myriad catalytic roles, thereby allowing RNA to compensate for its limited functional diversity.
Collapse
Affiliation(s)
- Jamie L. Bingaman
- Department of Chemistry and Center for RNA Molecular
Biology, The Pennsylvania State University, University Park, Pennsylvania 16802,
United States
| | - Sixue Zhang
- Department of Chemistry, University of Illinois at
Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United
States
| | - David R. Stevens
- Department of Chemistry, University of Illinois at
Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United
States
| | - Neela H. Yennawar
- X-ray Crystallography Facility, Huck Institutes of the Life
Sciences, The Pennsylvania State University, 8 Althouse Laboratory, University Park,
Pennsylvania 16802, United States
| | - Sharon Hammes-Schiffer
- Department of Chemistry, University of Illinois at
Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United
States
| | - Philip C. Bevilacqua
- Department of Chemistry and Center for RNA Molecular
Biology, The Pennsylvania State University, University Park, Pennsylvania 16802,
United States
- Department of Biochemistry and Molecular Biology, The
Pennsylvania State University, University Park, Pennsylvania 16802, United
States
| |
Collapse
|
32
|
Schuabb C, Kumar N, Pataraia S, Marx D, Winter R. Pressure modulates the self-cleavage step of the hairpin ribozyme. Nat Commun 2017; 8:14661. [PMID: 28358002 PMCID: PMC5379106 DOI: 10.1038/ncomms14661] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 01/20/2017] [Indexed: 01/01/2023] Open
Abstract
The ability of certain RNAs, denoted as ribozymes, to not only store genetic information but also catalyse chemical reactions gave support to the RNA world hypothesis as a putative step in the development of early life on Earth. This, however, might have evolved under extreme environmental conditions, including the deep sea with pressures in the kbar regime. Here we study pressure-induced effects on the self-cleavage of hairpin ribozyme by following structural changes in real-time. Our results suggest that compression of the ribozyme leads to an accelerated transesterification reaction, being the self-cleavage step, although the overall process is retarded in the high-pressure regime. The results reveal that favourable interactions between the reaction site and neighbouring nucleobases are strengthened under pressure, resulting therefore in an accelerated self-cleavage step upon compression. These results suggest that properly engineered ribozymes may also act as piezophilic biocatalysts in addition to their hitherto known properties.
Collapse
Affiliation(s)
- Caroline Schuabb
- Physikalische Chemie I-Biophysikalische Chemie, Fakultät für Chemie und Chemische Biologie, TU Dortmund, Otto-Hahn-Strasse 4a, Dortmund 44227, Germany
| | - Narendra Kumar
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, Bochum 44780, Germany
| | - Salome Pataraia
- Physikalische Chemie I-Biophysikalische Chemie, Fakultät für Chemie und Chemische Biologie, TU Dortmund, Otto-Hahn-Strasse 4a, Dortmund 44227, Germany
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, Bochum 44780, Germany
| | - Roland Winter
- Physikalische Chemie I-Biophysikalische Chemie, Fakultät für Chemie und Chemische Biologie, TU Dortmund, Otto-Hahn-Strasse 4a, Dortmund 44227, Germany
| |
Collapse
|
33
|
Giard A, Filhol JS, Jolibois F, Cavelier F, Berthomieu D. Prediction of pKa Using DFT: the Nicotianamine Polyacid Example. J Chem Theory Comput 2016; 12:5493-5500. [DOI: 10.1021/acs.jctc.6b00404] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Aude Giard
- Institut Charles
Gerhardt, MACS, UMR 5253 CNRS-ENSCM-UM, 8, rue de l’Ecole Normale, 34296 Montpellier cedex 5, France
| | - Jean-Sébastien Filhol
- Institut Charles
Gerhardt, CTMM, UMR 5253 CNRS-ENSCM-UM, Place Eugène Bataillon, 34296 Montpellier cedex 5, France
| | - Franck Jolibois
- LPCNO, UMR 5215
CNRS-INSA-UPS, 135 avenue de Rangueil 31077 Toulouse Cedex 4, France
| | - Florine Cavelier
- Institut des Biomolécules
Max Mousseron UMR 5247, CNRS -ENSCM-UM Place Eugène Bataillon, 34095 Montpellier cedex 5, France
| | - Dorothée Berthomieu
- Institut Charles
Gerhardt, MACS, UMR 5253 CNRS-ENSCM-UM, 8, rue de l’Ecole Normale, 34296 Montpellier cedex 5, France
| |
Collapse
|
34
|
Sengupta A, Sung HL, Nesbitt DJ. Amino Acid Specific Effects on RNA Tertiary Interactions: Single-Molecule Kinetic and Thermodynamic Studies. J Phys Chem B 2016; 120:10615-10627. [PMID: 27718572 DOI: 10.1021/acs.jpcb.6b05840] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In light of the current models for an early RNA-based universe, the potential influence of simple amino acids on tertiary folding of ribozymal RNA into biochemically competent structures is speculated to be of significant evolutionary importance. In the present work, the folding-unfolding kinetics of a ubiquitous tertiary interaction motif, the GAAA tetraloop-tetraloop receptor (TL-TLR), is investigated by single-molecule fluorescence resonance energy transfer spectroscopy in the presence of natural amino acids both with (e.g., lysine, arginine) and without (e.g., glycine) protonated side chain residues. By way of control, we also investigate the effects of a special amino acid (e.g., proline) and amino acid mimetic (e.g., betaine) that contain secondary or quaternary amine groups rather than a primary amine group. This combination permits systematic study of amino acid induced (or amino acid like) RNA folding dynamics as a function of side chain complexity, pKa, charge state, and amine group content. Most importantly, each of the naturally occurring amino acids is found to destabilize the TL-TLR tertiary folding equilibrium, the kinetic origin of which is dominated by a decrease in the folding rate constant (kdock), also affected by a strongly amino acid selective increase in the unfolding rate constant (kundock). To further elucidate the underlying thermodynamics, single-molecule equilibrium constants (Keq) for TL-TLR folding have been probed as a function of temperature, which reveal an amino acid dependent decrease in both overall exothermicity (ΔΔH° > 0) and entropic cost (-TΔΔS° < 0) for the overall folding process. Temperature-dependent studies on the folding/unfolding kinetic rate constants reveal analogous amino acid specific changes in both enthalpy (ΔΔH⧧) and entropy (ΔΔS⧧) for accessing the transition state barrier. The maximum destabilization of the TL-TLR tertiary interaction is observed for arginine, which is consistent with early studies of arginine and guanidine ion-inhibited self-splicing kinetics for the full Tetrahymena ribozyme [ Yarus , M. ; Christian , E. L. Nature 1989 , 342 , 349 - 350 ; Yarus , M. Science 1988 , 240 , 1751 - 1758 ].
Collapse
Affiliation(s)
- Abhigyan Sengupta
- JILA, National Institute of Standards and Technology and Department of Chemistry and Biochemistry, University of Colorado , Boulder, Colorado 80309, United States
| | - Hsuan-Lei Sung
- JILA, National Institute of Standards and Technology and Department of Chemistry and Biochemistry, University of Colorado , Boulder, Colorado 80309, United States
| | - David J Nesbitt
- JILA, National Institute of Standards and Technology and Department of Chemistry and Biochemistry, University of Colorado , Boulder, Colorado 80309, United States
| |
Collapse
|
35
|
Zhang S, Stevens D, Goyal P, Bingaman JL, Bevilacqua PC, Hammes-Schiffer S. Assessing the Potential Effects of Active Site Mg 2+ Ions in the glmS Ribozyme-Cofactor Complex. J Phys Chem Lett 2016; 7:3984-3988. [PMID: 27677922 PMCID: PMC5117136 DOI: 10.1021/acs.jpclett.6b01854] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 09/14/2016] [Indexed: 06/06/2023]
Abstract
Ribozymes employ diverse catalytic strategies in their self-cleavage mechanisms, including the use of divalent metal ions. This work explores the effects of Mg2+ ions in the active site of the glmS ribozyme-GlcN6P cofactor complex using computational methods. Deleterious and potentially beneficial effects of an active site Mg2+ ion on the self-cleavage reaction were identified. The presence of a Mg2+ ion near the scissile phosphate oxygen atoms at the cleavage site was determined to be deleterious, and thereby anticatalytic, due to electrostatic repulsion of the cofactor, disruption of key hydrogen-bonding interactions, and obstruction of nucleophilic attack. On the other hand, the presence of a Mg2+ ion at another position in the active site, the Hoogsteen face of the putative base, was found to avoid these deleterious effects and to be potentially catalytically favorable owing to the stabilization of negative charge and pKa shifting of the guanine base.
Collapse
Affiliation(s)
- Sixue Zhang
- Department
of Chemistry, University of Illinois at
Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801-3364, United States
| | - David
R. Stevens
- Department
of Chemistry, University of Illinois at
Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801-3364, United States
| | - Puja Goyal
- Department
of Chemistry, University of Illinois at
Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801-3364, United States
| | - Jamie L. Bingaman
- Department of Chemistry and Center
for RNA Molecular Biology and Department of Biochemistry
and Molecular Biology, The Pennsylvania
State University, University Park, Pennsylvania 16802, United States
| | - Philip C. Bevilacqua
- Department of Chemistry and Center
for RNA Molecular Biology and Department of Biochemistry
and Molecular Biology, The Pennsylvania
State University, University Park, Pennsylvania 16802, United States
| | - Sharon Hammes-Schiffer
- Department
of Chemistry, University of Illinois at
Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801-3364, United States
| |
Collapse
|
36
|
Kobori S, Yokobayashi Y. High-Throughput Mutational Analysis of a Twister Ribozyme. Angew Chem Int Ed Engl 2016; 55:10354-7. [PMID: 27461281 PMCID: PMC5113685 DOI: 10.1002/anie.201605470] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Revised: 07/04/2016] [Indexed: 01/17/2023]
Abstract
Recent discoveries of new classes of self‐cleaving ribozymes in diverse organisms have triggered renewed interest in the chemistry and biology of ribozymes. Functional analysis and engineering of ribozymes often involve performing biochemical assays on multiple ribozyme mutants. However, because each ribozyme mutant must be individually prepared and assayed, the number and variety of mutants that can be studied are severely limited. All of the single and double mutants of a twister ribozyme (a total of 10 296 mutants) were generated and assayed for their self‐cleaving activity by exploiting deep sequencing to count the numbers of cleaved and uncleaved sequences for every mutant. Interestingly, we found that the ribozyme is highly robust against mutations such that 71 % and 30 % of all single and double mutants, respectively, retain detectable activity under the assay conditions. It was also observed that the structural elements that comprise the ribozyme exhibit distinct sensitivity to mutations.
Collapse
Affiliation(s)
- Shungo Kobori
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904 0495, Japan
| | - Yohei Yokobayashi
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904 0495, Japan.
| |
Collapse
|
37
|
Kobori S, Yokobayashi Y. High-Throughput Mutational Analysis of a Twister Ribozyme. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201605470] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Shungo Kobori
- Nucleic Acid Chemistry and Engineering Unit; Okinawa Institute of Science and Technology Graduate University; Onna Okinawa 904 0495 Japan
| | - Yohei Yokobayashi
- Nucleic Acid Chemistry and Engineering Unit; Okinawa Institute of Science and Technology Graduate University; Onna Okinawa 904 0495 Japan
| |
Collapse
|
38
|
Ucisik MN, Bevilacqua PC, Hammes-Schiffer S. Molecular Dynamics Study of Twister Ribozyme: Role of Mg(2+) Ions and the Hydrogen-Bonding Network in the Active Site. Biochemistry 2016; 55:3834-46. [PMID: 27295275 PMCID: PMC5127262 DOI: 10.1021/acs.biochem.6b00203] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The recently discovered twister ribozyme is thought to utilize general acid-base catalysis in its self-cleavage mechanism, but the roles of nucleobases and metal ions in the mechanism are unclear. Herein, molecular dynamics simulations of the env22 twister ribozyme are performed to elucidate the structural and equilibrium dynamical properties, as well as to examine the role of Mg(2+) ions and possible candidates for the general base and acid in the self-cleavage mechanism. The active site region and the ends of the pseudoknots were found to be less mobile than other regions of the ribozyme, most likely providing structural stability and possibly facilitating catalysis. A purported catalytic Mg(2+) ion and the closest neighboring Mg(2+) ion remained chelated and relatively immobile throughout the microsecond trajectories, although removal of these Mg(2+) ions did not lead to any significant changes in the structure or equilibrium motions of the ribozyme on the microsecond time scale. In addition, a third metal ion, a Na(+) ion remained close to A1(O5'), the leaving group atom, during the majority of the microsecond trajectories, suggesting that it might stabilize the negative charge on A1(O5') during self-cleavage. The locations of these cations and their interactions with key nucleotides in the active site suggest that they may be catalytically relevant. The P1 stem is partially melted at its top and bottom in the crystal structure and further unwinds in the trajectories. The simulations also revealed an interconnected network comprised of hydrogen-bonding and π-stacking interactions that create a relatively rigid network around the self-cleavage site. The nucleotides involved in this network are among the highly conserved nucleotides in twister ribozymes, suggesting that this interaction network may be important to structure and function.
Collapse
Affiliation(s)
- Melek N Ucisik
- Department of Chemistry, University of Illinois at Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801-3364, United States
| | - Philip C Bevilacqua
- Department of Chemistry, Department of Biochemistry & Molecular Biology, and Center for RNA Molecular Biology, The Pennsylvania State University , University Park, Pennsylvania 16802, United States
| | - Sharon Hammes-Schiffer
- Department of Chemistry, University of Illinois at Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801-3364, United States
| |
Collapse
|
39
|
Casalino L, Palermo G, Rothlisberger U, Magistrato A. Who Activates the Nucleophile in Ribozyme Catalysis? An Answer from the Splicing Mechanism of Group II Introns. J Am Chem Soc 2016; 138:10374-7. [DOI: 10.1021/jacs.6b01363] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Lorenzo Casalino
- International School for Advanced Studies (SISSA), via Bonomea 265, 34136 Trieste, Italy
| | - Giulia Palermo
- Laboratory
of Computational Chemistry and Biochemistry, Institute of Chemical
Sciences and Engineering, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Ursula Rothlisberger
- Laboratory
of Computational Chemistry and Biochemistry, Institute of Chemical
Sciences and Engineering, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Alessandra Magistrato
- CNR-IOM-Democritos
National Simulation Center c/o SISSA, via Bonomea 265, 34136 Trieste, Italy
| |
Collapse
|
40
|
Wu D, Fajer MI, Cao L, Cheng X, Yang W. Generalized Ensemble Sampling of Enzyme Reaction Free Energy Pathways. Methods Enzymol 2016; 577:57-74. [PMID: 27498634 PMCID: PMC4978182 DOI: 10.1016/bs.mie.2016.05.012] [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] [Indexed: 06/11/2024]
Abstract
Free energy path sampling plays an essential role in computational understanding of chemical reactions, particularly those occurring in enzymatic environments. Among a variety of molecular dynamics simulation approaches, the generalized ensemble sampling strategy is uniquely attractive for the fact that it not only can enhance the sampling of rare chemical events but also can naturally ensure consistent exploration of environmental degrees of freedom. In this review, we plan to provide a tutorial-like tour on an emerging topic: generalized ensemble sampling of enzyme reaction free energy path. The discussion is largely focused on our own studies, particularly ones based on the metadynamics free energy sampling method and the on-the-path random walk path sampling method. We hope that this minipresentation will provide interested practitioners some meaningful guidance for future algorithm formulation and application study.
Collapse
Affiliation(s)
- D Wu
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, United States
| | - M I Fajer
- UT-ORNL Center for Molecular Biophysics, Oak Ridge National Laboratory, Oak Ridge, TN, United States; Florida State University, Tallahassee, FL, United States
| | - L Cao
- Florida State University, Tallahassee, FL, United States
| | - X Cheng
- UT-ORNL Center for Molecular Biophysics, Oak Ridge National Laboratory, Oak Ridge, TN, United States; The University of Tennessee, Knoxville, TN, United States.
| | - W Yang
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, United States; Florida State University, Tallahassee, FL, United States.
| |
Collapse
|
41
|
Giese TJ, York DM. Ambient-Potential Composite Ewald Method for ab Initio Quantum Mechanical/Molecular Mechanical Molecular Dynamics Simulation. J Chem Theory Comput 2016; 12:2611-32. [PMID: 27171914 DOI: 10.1021/acs.jctc.6b00198] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A new approach for performing Particle Mesh Ewald in ab initio quantum mechanical/molecular mechanical (QM/MM) simulations with extended atomic orbital basis sets is presented. The new approach, the Ambient-Potential Composite Ewald (CEw) method, does not perform the QM/MM interaction with Mulliken charges nor electrostatically fit charges. Instead the nuclei and electron density interact directly with the MM environment, but in a manner that avoids the use of dense Fourier transform grids. By performing the electrostatics with the underlying QM density, the CEw method avoids self-consistent field instabilities that have been encountered with simple charge mapping procedures. Potential of mean force (PMF) profiles of the p-nitrophenyl phosphate dissociation reaction in explicit solvent are computed from PBE0/6-31G* QM/MM molecular dynamics simulations with various electrostatic protocols. The CEw profiles are shown to be stable with respect to real-space Ewald cutoff, whereas the PMFs computed from truncated and switched electrostatics produce artifacts. PBE0/6-311G**, AM1/d-PhoT, and DFTB2 QM/MM simulations are performed to generate two-dimensional PMF profiles of the phosphoryl transesterification reactions with ethoxide and phenoxide leaving groups. The semiempirical models incorrectly produce a concerted ethoxide mechanism, whereas PBE0 correctly produces a stepwise mechanism. The ab initio reaction barriers agree more closely to experiment than the semiempirical models. The failure of Mulliken-charge QM/MM-Ewald is analyzed.
Collapse
Affiliation(s)
- Timothy J Giese
- Center for Integrative Proteomics Research and Department of Chemistry and Chemical Biology, Rutgers University , Piscataway, New Jersey 08854-8087, United States
| | - Darrin M York
- Center for Integrative Proteomics Research and Department of Chemistry and Chemical Biology, Rutgers University , Piscataway, New Jersey 08854-8087, United States
| |
Collapse
|
42
|
Kuechler ER, Giese TJ, York DM. VR-SCOSMO: A smooth conductor-like screening model with charge-dependent radii for modeling chemical reactions. J Chem Phys 2016; 144:164115. [PMID: 27131539 PMCID: PMC4851621 DOI: 10.1063/1.4946779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 04/01/2016] [Indexed: 12/23/2022] Open
Abstract
To better represent the solvation effects observed along reaction pathways, and of ionic species in general, a charge-dependent variable-radii smooth conductor-like screening model (VR-SCOSMO) is developed. This model is implemented and parameterized with a third order density-functional tight binding quantum model, DFTB3/3OB-OPhyd, a quantum method which was developed for organic and biological compounds, utilizing a specific parameterization for phosphate hydrolysis reactions. Unlike most other applications with the DFTB3/3OB model, an auxiliary set of atomic multipoles is constructed from the underlying DFTB3 density matrix which is used to interact the solute with the solvent response surface. The resulting method is variational, produces smooth energies, and has analytic gradients. As a baseline, a conventional SCOSMO model with fixed radii is also parameterized. The SCOSMO and VR-SCOSMO models shown have comparable accuracy in reproducing neutral-molecule absolute solvation free energies; however, the VR-SCOSMO model is shown to reduce the mean unsigned errors (MUEs) of ionic compounds by half (about 2-3 kcal/mol). The VR-SCOSMO model presents similar accuracy as a charge-dependent Poisson-Boltzmann model introduced by Hou et al. [J. Chem. Theory Comput. 6, 2303 (2010)]. VR-SCOSMO is then used to examine the hydrolysis of trimethylphosphate and seven other phosphoryl transesterification reactions with different leaving groups. Two-dimensional energy landscapes are constructed for these reactions and calculated barriers are compared to those obtained from ab initio polarizable continuum calculations and experiment. Results of the VR-SCOSMO model are in good agreement in both cases, capturing the rate-limiting reaction barrier and the nature of the transition state.
Collapse
Affiliation(s)
- Erich R Kuechler
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854-8087, USA
| | - Timothy J Giese
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854-8087, USA
| | - Darrin M York
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854-8087, USA
| |
Collapse
|
43
|
Chen Y, Dong H, Zhang H. Experimental and Computational Evidence for the Reduction Mechanisms of Aromatic N-oxides by Aqueous Fe(II)-Tiron Complex. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:249-58. [PMID: 26636617 DOI: 10.1021/acs.est.5b04900] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A combined experimental-theoretical approach was taken to elucidate the reduction mechanisms of five representative aromatic N-oxides (ANOs) by Fe(II)-tiron complex and to identify the rate-limiting step. Based on the possible types of complexes formed with the reductant, three groups of ANOs were studied: type I refers to those forming 5-membered ring complexes through the N and O atoms on the side chain; type II refers to those forming 6-membered ring complexes through the N-oxide O atom and the O atom on the side chain; and type III refers to complexation through the N-oxide O atom only. Density functional theory calculations suggested that the elementary reactions, including protonation, N-O bond cleavage, and the second electron transfer processes, are barrierless, indicating that the first electron transfer is rate-limiting. Consistent with the theoretical results, the experimental solvent isotope effect, KIEH, for the reduction of quinoline N-oxide (a type III ANO) was obtained to be 1.072 ± 0.025, suggesting protonation was not involved in the rate-limiting step. The measured nitrogen kinetic isotope effect, KIEN, for the reduction of pyridine N-oxide (a type III ANO) (1.022 ± 0.006) is in good agreement with the calculated KIEN for its first electron transfer (1.011-1.028), confirming that the first electron transfer is rate-limiting. Electrochemical cell experiments demonstrated that the electron transfer process can be facilitated significantly by type I complexation with FeL2(6-) (1:2 Fe(II)-tiron complex), to some extent by type II complexation with free Fe(II), but not by weak type III complexation.
Collapse
Affiliation(s)
- Yiling Chen
- Department of Civil and Environmental Engineering, Temple University , Philadelphia, Pennsylvania 19122, United States
| | - Hao Dong
- Kuang Yaming Honors School, Nanjing University , Nanjing 210093, People's Republic of China
- Institute for Computational Molecular Science, Temple University , Philadelphia, Pennsylvania 19122, United States
| | - Huichun Zhang
- Department of Civil and Environmental Engineering, Temple University , Philadelphia, Pennsylvania 19122, United States
| |
Collapse
|
44
|
Dubecký M, Walter NG, Šponer J, Otyepka M, Banáš P. Chemical feasibility of the general acid/base mechanism of glmS ribozyme self-cleavage. Biopolymers 2015; 103:550-62. [PMID: 25858644 PMCID: PMC4553064 DOI: 10.1002/bip.22657] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Revised: 03/17/2015] [Accepted: 04/02/2015] [Indexed: 01/28/2023]
Abstract
In numerous Gram-positive bacteria, the glmS ribozyme or catalytic riboswitch regulates the expression of glucosamine-6-phosphate (GlcN6P) synthase via site-specific cleavage of its sugar-phosphate backbone in response to GlcN6P ligand binding. Biochemical data have suggested a crucial catalytic role for an active site guanine (G40 in Thermoanaerobacter tengcongensis, G33 in Bacillus anthracis). We used hybrid quantum chemical/molecular mechanical (QM/MM) calculations to probe the mechanism where G40 is deprotonated and acts as a general base. The calculations suggest that the deprotonated guanine G40(-) is sufficiently reactive to overcome the thermodynamic penalty arising from its rare protonation state, and thus is able to activate the A-1(2'-OH) group toward nucleophilic attack on the adjacent backbone. Furthermore, deprotonation of A-1(2'-OH) and nucleophilic attack are predicted to occur as separate steps, where activation of A-1(2'-OH) precedes nucleophilic attack. Conversely, the transition state associated with the rate-determining step corresponds to concurrent nucleophilic attack and protonation of the G1(O5') leaving group by the ammonium moiety of the GlcN6P cofactor. Overall, our calculations help to explain the crucial roles of G40 (as a general base) and GlcN6P (as a general acid) during glmS ribozyme self-cleavage. In addition, we show that the QM/MM description of the glmS ribozyme self-cleavage reaction is significantly more sensitive to the size of the QM region and the quality of the QM-MM coupling than that of other small ribozymes.
Collapse
Affiliation(s)
- Matúš Dubecký
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, tř. 17 listopadu 12, 771 46, Olomouc, Czech Republic
| | - Nils G. Walter
- Department of Chemistry, Single Molecule Analysis Group, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055
| | - Jiří Šponer
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, 612 65 Brno, Czech Republic
- CEITEC – Central European Institute of Technology, Campus Bohunice, Kamenice 5, 625 00
| | - Michal Otyepka
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, tř. 17 listopadu 12, 771 46, Olomouc, Czech Republic
| | - Pavel Banáš
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, tř. 17 listopadu 12, 771 46, Olomouc, Czech Republic
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, 612 65 Brno, Czech Republic
| |
Collapse
|
45
|
González-Olvera JC, Martínez-Reyes J, González-Jasso E, Pless RC. Determination of pKa values for deprotonable nucleobases in short model oligonucleotides. Biophys Chem 2015; 206:58-65. [PMID: 26188860 DOI: 10.1016/j.bpc.2015.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 07/01/2015] [Accepted: 07/06/2015] [Indexed: 10/23/2022]
Abstract
The deprotonation of ionizable nucleobases centrally placed in short model oligonucleotides was examined under different physical conditions, using UV absorption spectroscopy. The oligonucleotide sequences were designed so that only the central base would be ionized over the pH range examined. pKa values of 9.90±0.01 and 9.34±0.04 were determined for the guanine group in the oligomer d-ACAGCAC and 2'-deoxyguanosine, respectively, both at 25°C and 0.1M NaCl. Lengthening the oligonucleotide up to the tridecamer stage further increases the pKa of the central guanine moiety. Electrolyte concentration, temperature, and mixed water-ethanol solvents affect the acidity of the central base. Changes in the sequence surrounding the central guanine can also have a significant effect, especially in the case of strongly stacking sequences. The pKa values were also determined for the hepta(2'-O-methyl)ribonucleotide and the heptamer PNA of identical sequence, as well as for oligodeoxyribonucleotides with different deprotonable bases, viz. thymine, uracil, or hypoxanthine, in the central position. The results are interpreted in terms of the electric-field effect exerted on the departing proton by the negative electric charges located on the internucleotide phosphate groups, and calculations show this effect to approximately explain the magnitude of the pKa difference observed between the deoxyriboheptanucleotide and its electroneutral PNA analogue.
Collapse
Affiliation(s)
- Julio C González-Olvera
- Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Instituto Politécnico Nacional, Querétaro, Querétaro 76090, Mexico
| | - José Martínez-Reyes
- Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Instituto Politécnico Nacional, Querétaro, Querétaro 76090, Mexico
| | - Eva González-Jasso
- Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Instituto Politécnico Nacional, Querétaro, Querétaro 76090, Mexico
| | - Reynaldo C Pless
- Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Instituto Politécnico Nacional, Querétaro, Querétaro 76090, Mexico.
| |
Collapse
|
46
|
Dong X, Tian Z, Yang X, Xue Y. Theoretical study on the mechanism of self-cleavage reaction of the glmS ribozyme. Theor Chem Acc 2015. [DOI: 10.1007/s00214-015-1667-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
47
|
Thaplyal P, Ganguly A, Hammes-Schiffer S, Bevilacqua PC. Inverse thio effects in the hepatitis delta virus ribozyme reveal that the reaction pathway is controlled by metal ion charge density. Biochemistry 2015; 54:2160-75. [PMID: 25799319 PMCID: PMC4824481 DOI: 10.1021/acs.biochem.5b00190] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
![]()
The
hepatitis delta virus (HDV) ribozyme self-cleaves in the presence
of a wide range of monovalent and divalent ions. Prior theoretical
studies provided evidence that self-cleavage proceeds via a concerted
or stepwise pathway, with the outcome dictated by the valency of the
metal ion. In the present study, we measure stereospecific thio effects
at the nonbridging oxygens of the scissile phosphate under a wide
range of experimental conditions, including varying concentrations
of diverse monovalent and divalent ions, and combine these with quantum
mechanical/molecular mechanical (QM/MM) free energy simulations on
the stereospecific thio substrates. The RP substrate gives large normal thio effects in the presence of all
monovalent ions. The SP substrate also
gives normal or no thio effects, but only for smaller monovalent and
divalent cations, such as Li+, Mg2+, Ca2+, and Sr2+; in contrast, sizable inverse thio
effects are found for larger monovalent and divalent cations, including
Na+, K+, NH4+, and Ba2+. Proton inventories are found to be unity in the presence
of the larger monovalent and divalent ions, but two in the presence
of Mg2+. Additionally, rate–pH profiles are inverted
for the low charge density ions, and only imidazole plus ammonium
ions rescue an inactive C75Δ variant in the absence of Mg2+. Results from the thio effect experiments, rate–pH
profiles, proton inventories, and ammonium/imidazole rescue experiments,
combined with QM/MM free energy simulations, support a change in the
mechanism of HDV ribozyme self-cleavage from concerted and metal ion-stabilized
to stepwise and proton transfer-stabilized as the charge density of
the metal ion decreases.
Collapse
Affiliation(s)
- Pallavi Thaplyal
- †Department of Chemistry and Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Abir Ganguly
- ‡Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Sharon Hammes-Schiffer
- ‡Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Philip C Bevilacqua
- †Department of Chemistry and Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| |
Collapse
|