1
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Benayad Z, David R, Stirnemann G. Prebiotic chemical reactivity in solution with quantum accuracy and microsecond sampling using neural network potentials. Proc Natl Acad Sci U S A 2024; 121:e2322040121. [PMID: 38809704 PMCID: PMC11161780 DOI: 10.1073/pnas.2322040121] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 04/26/2024] [Indexed: 05/31/2024] Open
Abstract
While RNA appears as a good candidate for the first autocatalytic systems preceding the emergence of modern life, the synthesis of RNA oligonucleotides without enzymes remains challenging. Because the uncatalyzed reaction is extremely slow, experimental studies bring limited and indirect information on the reaction mechanism, the nature of which remains debated. Here, we develop neural network potentials (NNPs) to study the phosphoester bond formation in water. While NNPs are becoming routinely applied to nonreactive systems or simple reactions, we demonstrate how they can systematically be trained to explore the reaction phase space for complex reactions involving several proton transfers and exchanges of heavy atoms. We then propagate at moderate computational cost hundreds of nanoseconds of a variety of enhanced sampling simulations with quantum accuracy in explicit solvent conditions. The thermodynamically preferred reaction pathway is a concerted, dissociative mechanism, with the transient formation of a metaphosphate transition state and direct participation of water solvent molecules that facilitate the exchange of protons through the nonbridging phosphate oxygens. Associative-dissociative pathways, characterized by a much tighter pentacoordinated phosphate, are higher in free energy. Our simulations also suggest that diprotonated phosphate, whose reactivity is never directly assessed in the experiments, is significantly less reactive than the monoprotonated species, suggesting that it is probably never the reactive species in normal pH conditions. These observations rationalize unexplained experimental results and the temperature dependence of the reaction rate, and they pave the way for the design of more efficient abiotic catalysts and activating groups.
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Affiliation(s)
- Zakarya Benayad
- CNRS Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, Paris Sciences et Lettres University, Université Paris-Cité, 75005Paris, France
- PASTEUR, Département de Chimie, École Normale Supérieure, Paris Sciences et Lettres University, Sorbonne University, CNRS, 75005Paris, France
| | - Rolf David
- CNRS Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, Paris Sciences et Lettres University, Université Paris-Cité, 75005Paris, France
- PASTEUR, Département de Chimie, École Normale Supérieure, Paris Sciences et Lettres University, Sorbonne University, CNRS, 75005Paris, France
| | - Guillaume Stirnemann
- CNRS Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, Paris Sciences et Lettres University, Université Paris-Cité, 75005Paris, France
- PASTEUR, Département de Chimie, École Normale Supérieure, Paris Sciences et Lettres University, Sorbonne University, CNRS, 75005Paris, France
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2
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Benayad Z, Bova Saint-André M, Stirnemann G. Molecular Mechanisms of Phosphoester Bond Formation in Water Using Tight-Binding Ab Initio Molecular Dynamics. J Phys Chem B 2022; 126:8251-8265. [PMID: 36201374 DOI: 10.1021/acs.jpcb.2c04259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Phosphate groups are ubiquitous in biomolecules and are usually incorporated through phosphoester bonds between alcohol groups and orthophosphate. The formation of this bond is exceptionally difficult, with associated barriers of 30-45 kcal/mol in the absence of catalysts. In abiotic conditions, polymerizing nucleic acids without enzymes remains very challenging and is still a partly unsolved problem that severely questions the RNA World hypothesis for the origins of life. Offering a solution to this problem would involve a detailed knowledge of the reaction energetics and mechanisms, yet these remain not fully understood at a molecular level, especially because of the very slow reaction rates that represent a significant challenge for the experiments. The number of involved reaction coordinates and the possible role of the solvent in assisting the reaction are challenging for computational studies. Here, we use extensive ab initio molecular dynamics simulations using semiempirical tight-binding methods and enhanced sampling to address these issues. We first show that the choice of the tight-binding method is greatly limited by the instability of the water liquid phase for most DFTB generations and parameter sets that are widely available. We then focus on a model reaction involving methanol and orthophosphate, for which the two protonation states (mono- and dianionic) that are dominant around neutral pH are considered. We compare different proton coordinates that enable (or not) the participation of solvent water molecules. Our simulations suggest that in all cases, a dissociative associative mechanism, with an intermediate metaphosphate, is favored. The main difference between the two phosphate species is that reaction with the monoanion is assisted by the substrate, while that with the dianion involves solvent water molecules. Our results are in agreement with early experimental measurements, but the reaction barriers are underestimated in our framework. We believe that our approach provides an interesting perspective on how to sample the reaction phase space efficiently, but it calls for future studies using more accurate descriptions of chemical reactivity.
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Affiliation(s)
- Zakarya Benayad
- CNRS Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, PSL University, Université de Paris, 13 rue Pierre et Marie Curie, 75005Paris, France
| | - Matthias Bova Saint-André
- CNRS Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, PSL University, Université de Paris, 13 rue Pierre et Marie Curie, 75005Paris, France
| | - Guillaume Stirnemann
- CNRS Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, PSL University, Université de Paris, 13 rue Pierre et Marie Curie, 75005Paris, France
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3
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Dasgupta S, Aullón G, Zangrando E, Das D. Mapping the working route of phosphate monoester hydrolysis catalyzed by copper based models with special emphasis on the role of oxoanions by experimental and theoretical studies. NEW J CHEM 2019. [DOI: 10.1039/c8nj04018d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The mechanistic pathway of phosphate-ester bond hydrolysis with special emphasis on the role of oxoanions was explored by experimental and theoretical study.
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Affiliation(s)
| | - Gabriel Aullón
- Departament de Química Inorgànica i Orgànica (Secció de Química Inorgànica) and Institut de QuímicaTeorica i Computacional
- Universitat de Barcelona
- 08028 Barcelona
- Spain
| | - Ennio Zangrando
- Department of Chemical and Pharmaceutical Sciences
- University of Trieste
- 34127 Trieste
- Italy
| | - Debasis Das
- Department of Chemistry
- University of Calcutta
- Kolkata 700009
- India
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4
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Yu X, Jiang J. Mineralization and cementing properties of bio-carbonate cement, bio-phosphate cement, and bio-carbonate/phosphate cement: a review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:21483-21497. [PMID: 29948713 DOI: 10.1007/s11356-018-2143-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 04/25/2018] [Indexed: 06/08/2023]
Abstract
Due to high pollution associated with traditional Portland cement and bio-carbonate cement, a new generation of cementitious material needs to be developed. Bio-barium phosphate, magnesium phosphate, and ferric phosphate are synthesized by bio-mineralization. Firstly, the substrate is hydrolyzed by alkaline phosphatase secreted via phosphate-mineralization microbes, obtaining phosphate ions. Micro- and nano-scale phosphate minerals are prepared by phosphate ions reacting with different types of metal cation. The setting time of bio-BaHPO4 has a greater effect on the strength of sand columns when a mixing precipitation process is innovatively adopted. The strength of the sand columns increases as bio-BaHPO4 content (10~50%) increases. The optimum content of bio-BaHPO4 is 60%. Porosity and permeability of the sand columns decrease as bio-BaHPO4 content (10~60%) increases. Ammonium and ammonia can effectively be synthesized to magnesium ammonium phosphate by adding K2HPO4·3H2O to Sporosarcina pasteurii liquid. Permeability, porosity, and compressive strength of the sand columns are close to CJ1, CJ1.5, and CJ2 cementation. However, the fixation ammonia ratio of CJ2 is bigger than CJ1 and CJ1.5 (The mixture solutions of Sporosarcina pasteurii and K2HPO4·3H2O (1, 1.5, and 2 mol/L) are named as CJ1, CJ1.5, and CJ2) cementation. The results show that the Sporosarcina pasteurii liquid containing K2HPO4·3H2O (2 mol/L) and the mixture solution of MgCl2 and urea (3 mol/L) cemented loose sand particles best. Two types of bio-cement are environmentally friendly and can partially or completely replace bio-carbonate cement.
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Affiliation(s)
- Xiaoniu Yu
- School of Environment, Tsinghua University, Beijing, 100084, China
- College of Architecture and Civil Engineering, Wenzhou University, Wenzhou, 325035, China
| | - Jianguo Jiang
- School of Environment, Tsinghua University, Beijing, 100084, China.
- Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China, Beijing, 100084, China.
- Collaborative Innovation Center for Regional Environmental Quality, Tsinghua University, Beijing, 100084, China.
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5
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Petrović D, Szeler K, Kamerlin SCL. Challenges and advances in the computational modeling of biological phosphate hydrolysis. Chem Commun (Camb) 2018; 54:3077-3089. [PMID: 29412205 DOI: 10.1039/c7cc09504j] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Phosphate ester hydrolysis is fundamental to many life processes, and has been the topic of substantial experimental and computational research effort. However, even the simplest of phosphate esters can be hydrolyzed through multiple possible pathways that can be difficult to distinguish between, either experimentally, or computationally. Therefore, the mechanisms of both the enzymatic and non-enzymatic reactions have been historically controversial. In the present contribution, we highlight a number of technical issues involved in reliably modeling these computationally challenging reactions, as well as proposing potential solutions. We also showcase examples of our own work in this area, discussing both the non-enzymatic reaction in aqueous solution, as well as insights obtained from the computational modeling of organophosphate hydrolysis and catalytic promiscuity amongst enzymes that catalyze phosphoryl transfer.
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Affiliation(s)
- Dušan Petrović
- Department of Cell and Molecular Biology, Uppsala University, BMC Box 596, S-751 24 Uppsala, Sweden.
| | - Klaudia Szeler
- Department of Cell and Molecular Biology, Uppsala University, BMC Box 596, S-751 24 Uppsala, Sweden.
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6
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Acosta-Silva C, Bertran J, Branchadell V, Oliva A. Phosphoryl Transfer Reaction in RNA: Is the Substrate-Assisted Catalysis a Possible Mechanism in Certain Solvents? J Phys Chem A 2017; 121:8525-8534. [PMID: 29039953 DOI: 10.1021/acs.jpca.7b09156] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A proton shuttle mechanism for the phosphoryl transfer reaction in RNA, in which a proton is transferred from the nucleophile to the leaving group through a nonbridged oxygen atom of the phosphate, was explored using the MO6-2X density functional method and the solvent continuum model. This reaction is the initial step of the RNA hydrolysis. We used different solvents characterized by their dielectric constant, and, for each of them, we studied the nuclear and electronic relaxation, produced by the solvent reaction field, for the stationary points. Given that RNA has a poor leaving group, the bond breaking corresponds to the rate-determining step. If the O atom is substituted by a S atom, the leaving group is now good, and the rate-determining step is now the nucleophilic attack concerted with the proton transfer. The most relevant result we found is that none of the solvents we studied has a free energy of activation that is smaller than the one in water. This suggests that the enzyme catalysis following this mechanism must be due to the permanent electric field that is created by a preorganized charge distribution but not to the solvent reaction field.
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Affiliation(s)
- Carles Acosta-Silva
- Department of Chemistry, Universitat Autònoma de Barcelona , 08193 Bellaterra, Spain
| | - Joan Bertran
- Department of Chemistry, Universitat Autònoma de Barcelona , 08193 Bellaterra, Spain
| | - Vicenç Branchadell
- Department of Chemistry, Universitat Autònoma de Barcelona , 08193 Bellaterra, Spain
| | - Antoni Oliva
- Department of Chemistry, Universitat Autònoma de Barcelona , 08193 Bellaterra, Spain
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7
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Duarte F, Barrozo A, Åqvist J, Williams NH, Kamerlin SCL. The Competing Mechanisms of Phosphate Monoester Dianion Hydrolysis. J Am Chem Soc 2016; 138:10664-73. [PMID: 27471914 PMCID: PMC4999962 DOI: 10.1021/jacs.6b06277] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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Despite the numerous
experimental and theoretical studies on phosphate
monoester hydrolysis, significant questions remain concerning the
mechanistic details of these biologically critical reactions. In the
present work we construct a linear free energy relationship for phosphate
monoester hydrolysis to explore the effect of modulating leaving group
pKa on the competition between solvent-
and substrate-assisted pathways for the hydrolysis of these compounds.
Through detailed comparative electronic-structure studies of methyl
phosphate and a series of substituted aryl phosphate monoesters, we
demonstrate that the preferred mechanism is dependent on the nature
of the leaving group. For good leaving groups, a strong preference
is observed for a more dissociative solvent-assisted pathway. However,
the energy difference between the two pathways gradually reduces as
the leaving group pKa increases and creates
mechanistic ambiguity for reactions involving relatively poor alkoxy
leaving groups. Our calculations show that the transition-state structures
vary smoothly across the range of pKas
studied and that the pathways remain discrete mechanistic alternatives.
Therefore, while not impossible, a biological catalyst would have
to surmount a significantly higher activation barrier to facilitate
a substrate-assisted pathway than for the solvent-assisted pathway
when phosphate is bonded to good leaving groups. For poor leaving
groups, this intrinsic preference disappears.
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Affiliation(s)
- Fernanda Duarte
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University , BMC Box 596, SE-751 24 Uppsala, Sweden
| | - Alexandre Barrozo
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University , BMC Box 596, SE-751 24 Uppsala, Sweden
| | - Johan Åqvist
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University , BMC Box 596, SE-751 24 Uppsala, Sweden
| | - Nicholas H Williams
- Department of Chemistry, Sheffield University , Sheffield S3 7HF, United Kingdom
| | - Shina C L Kamerlin
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University , BMC Box 596, SE-751 24 Uppsala, Sweden
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8
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Acosta-Silva C, Bertran J, Branchadell V, Oliva A. Theoretical Insights on the Mechanism of the GTP Hydrolysis Catalyzed by the Elongation Factor Tu (EF-Tu). J Phys Chem B 2015; 120:89-101. [PMID: 26653849 DOI: 10.1021/acs.jpcb.5b10145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The purpose of this work is to have a better understanding of the mechanism of GTP hydrolysis catalyzed by the elongation factor Tu. Two main aspects are being discussed in the literature: the associative or dissociative character of the process and the nature of nucleophile activation. The calculations of the QM subsystem have been done by means of the M06-2X density functional and the split valence triple-ζ 6-311+G(d,p) basis set. The environmental effect has been introduced through the continuum SMD method. We have studied three models of increasing complexity in order to analyze the different factors that intervene in the catalytic action. The results obtained in this paper confirm that the protonated His84 plays a fundamental role in the catalytic mechanism, but we have also found that the crystallographic sodium ion has a notable effect in the catalysis. So, our work has permitted a new insight, complementary to those obtained with QM/MM calculations, into this very complex process.
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Affiliation(s)
- Carles Acosta-Silva
- Departament de Química, Universitat Autònoma de Barcelona , 08193 Bellaterra, Spain
| | - Joan Bertran
- Departament de Química, Universitat Autònoma de Barcelona , 08193 Bellaterra, Spain
| | - Vicenç Branchadell
- Departament de Química, Universitat Autònoma de Barcelona , 08193 Bellaterra, Spain
| | - Antoni Oliva
- Departament de Química, Universitat Autònoma de Barcelona , 08193 Bellaterra, Spain
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9
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Marcos E, Crehuet R, Anglada JM. Inductive and External Electric Field Effects in Pentacoordinated Phosphorus Compounds. J Chem Theory Comput 2015; 4:49-63. [PMID: 26619979 DOI: 10.1021/ct700220z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Pentacoordination at phosphorus is associated with a nucleophilic displacement reaction at tetracoordinated phosphorus compounds and shows a great variability in what respects their geometrical and energetic features. By means of a systematic theoretical study on a series of elementary model compounds, we have analyzed the bonding features. The pentacoordinated phosphorus compounds are held together by dative bonds, and the geometry and stability depends on the inductive effects originated by different substitutes at phosphorus. We show also that an external electric field can modify the geometrical features and the reactivity of the nucleophilic substitution reactions. This issue may have great interest in biological reactions involving pentacoordinated phosphorus where the electric field originated by the folded protein could influence the catalytic process. We report also additional calculations on the geometry and NMR spectra on three triphenyl phosphonium ylide derivatives, and our results compare well with the experimental data.
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Affiliation(s)
- Enrique Marcos
- Grup de Química Teòrica i Computacional, Departament de Química Orgànica Biològica, Institut d'Investigacions Químiques i Ambientals de Barcelona, IIQAB - CSIC, c/ Jordi Girona 18, E-08034 Barcelona, Spain
| | - Ramon Crehuet
- Grup de Química Teòrica i Computacional, Departament de Química Orgànica Biològica, Institut d'Investigacions Químiques i Ambientals de Barcelona, IIQAB - CSIC, c/ Jordi Girona 18, E-08034 Barcelona, Spain
| | - Josep M Anglada
- Grup de Química Teòrica i Computacional, Departament de Química Orgànica Biològica, Institut d'Investigacions Químiques i Ambientals de Barcelona, IIQAB - CSIC, c/ Jordi Girona 18, E-08034 Barcelona, Spain
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10
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Duarte F, Åqvist J, Williams NH, Kamerlin SCL. Resolving apparent conflicts between theoretical and experimental models of phosphate monoester hydrolysis. J Am Chem Soc 2014; 137:1081-93. [PMID: 25423607 PMCID: PMC4311964 DOI: 10.1021/ja5082712] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
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Understanding
phosphoryl and sulfuryl transfer is central to many
biochemical processes. However, despite decades of experimental and
computational studies, a consensus concerning the precise mechanistic
details of these reactions has yet to be reached. In this work we
perform a detailed comparative theoretical study of the hydrolysis
of p-nitrophenyl phosphate, methyl phosphate and p-nitrophenyl sulfate, all of which have served as key model
systems for understanding phosphoryl and sulfuryl transfer reactions,
respectively. We demonstrate the existence of energetically similar
but mechanistically distinct possibilities for phosphate monoester
hydrolysis. The calculated kinetic isotope effects for p-nitrophenyl phosphate provide a means to discriminate between substrate-
and solvent-assisted pathways of phosphate monoester hydrolysis, and
show that the solvent-assisted pathway dominates in solution. This
preferred mechanism for p-nitrophenyl phosphate hydrolysis
is difficult to find computationally due to the limitations of compressing
multiple bonding changes onto a 2-dimensional energy surface. This
problem is compounded by the need to include implicit solvation to
at least microsolvate the system and stabilize the highly charged
species. In contrast, methyl phosphate hydrolysis shows a preference
for a substrate-assisted mechanism. For p-nitrophenyl
sulfate hydrolysis there is only one viable reaction pathway, which
is similar to the solvent-assisted pathway for phosphate hydrolysis,
and the substrate-assisted pathway is not accessible. Overall, our
results provide a unifying mechanistic framework that is consistent
with the experimentally measured kinetic isotope effects and reconciles
the discrepancies between theoretical and experimental models for
these biochemically ubiquitous classes of reaction.
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Affiliation(s)
- Fernanda Duarte
- Department of Cell and Molecular Biology (ICM), Uppsala University , SE-751 24 Uppsala, Sweden
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Xia F, Zhang Q, Tian K, Zhu H. Theoretical studies on the effect of sulfur substitution for the methanolysis of cyclic and acyclic phosphate esters. COMPUT THEOR CHEM 2014. [DOI: 10.1016/j.comptc.2014.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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12
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Ferreira DE, Boldt IS, De Almeida WB, Rocha WR, Nome F. Quantum mechanical/effective fragment potential (QM/EFP) study of phosphate diester cleavage in aqueous solution. COMPUT THEOR CHEM 2014. [DOI: 10.1016/j.comptc.2014.05.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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13
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Density functional calculations on alcoholysis and thiolysis of phosphate triesters: Stepwise or concerted? COMPUT THEOR CHEM 2013. [DOI: 10.1016/j.comptc.2013.05.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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14
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Hong HJ, Lee J, Bae AR, Um IH. Kinetics and Reaction Mechanism for Alkaline Hydrolysis of Y-Substituted-Phenyl Diphenylphosphinates. B KOREAN CHEM SOC 2013. [DOI: 10.5012/bkcs.2013.34.7.2001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Abstract
Phosphoryl transfer plays key roles in signaling, energy transduction, protein synthesis, and maintaining the integrity of the genetic material. On the surface, it would appear to be a simple nucleophile displacement reaction. However, this simplicity is deceptive, as, even in aqueous solution, the low-lying d-orbitals on the phosphorus atom allow for eight distinct mechanistic possibilities, before even introducing the complexities of the enzyme catalyzed reactions. To further complicate matters, while powerful, traditional experimental techniques such as the use of linear free-energy relationships (LFER) or measuring isotope effects cannot make unique distinctions between different potential mechanisms. A quarter of a century has passed since Westheimer wrote his seminal review, 'Why Nature Chose Phosphate' (Science 235 (1987), 1173), and a lot has changed in the field since then. The present review revisits this biologically crucial issue, exploring both relevant enzymatic systems as well as the corresponding chemistry in aqueous solution, and demonstrating that the only way key questions in this field are likely to be resolved is through careful theoretical studies (which of course should be able to reproduce all relevant experimental data). Finally, we demonstrate that the reason that nature really chose phosphate is due to interplay between two counteracting effects: on the one hand, phosphates are negatively charged and the resulting charge-charge repulsion with the attacking nucleophile contributes to the very high barrier for hydrolysis, making phosphate esters among the most inert compounds known. However, biology is not only about reducing the barrier to unfavorable chemical reactions. That is, the same charge-charge repulsion that makes phosphate ester hydrolysis so unfavorable also makes it possible to regulate, by exploiting the electrostatics. This means that phosphate ester hydrolysis can not only be turned on, but also be turned off, by fine tuning the electrostatic environment and the present review demonstrates numerous examples where this is the case. Without this capacity for regulation, it would be impossible to have for instance a signaling or metabolic cascade, where the action of each participant is determined by the fine-tuned activity of the previous piece in the production line. This makes phosphate esters the ideal compounds to facilitate life as we know it.
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16
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Maxwell CI, Liu CT, Neverov AA, Mosey NJ, Brown RS. Transition from concerted to stepwise processes as a function of leaving group ability: density functional theory and experimental study of lyoxide-promoted cleavages of phosphorothioate and phosphate triesters in water and methanol. J PHYS ORG CHEM 2011. [DOI: 10.1002/poc.1938] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - C. Tony Liu
- Department of Chemistry; Queen's University; Kingston Ontario Canada K7L 3N6
| | - Alexei A. Neverov
- Department of Chemistry; Queen's University; Kingston Ontario Canada K7L 3N6
| | - Nicholas J. Mosey
- Department of Chemistry; Queen's University; Kingston Ontario Canada K7L 3N6
| | - Robert Stan Brown
- Department of Chemistry; Queen's University; Kingston Ontario Canada K7L 3N6
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17
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Kamerlin SCL. Theoretical Comparison of p-Nitrophenyl Phosphate and Sulfate Hydrolysis in Aqueous Solution: Implications for Enzyme-Catalyzed Sulfuryl Transfer. J Org Chem 2011; 76:9228-38. [DOI: 10.1021/jo201104v] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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18
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Murgia S, Lampis S, Zucca P, Sanjust E, Monduzzi M. Nucleotide recognition and phosphate linkage hydrolysis at a lipid cubic interface. J Am Chem Soc 2010; 132:16176-84. [PMID: 20977215 DOI: 10.1021/ja1069745] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Mononucleotides, when entrapped within a mono-olein-based cubic Ia3d liquid crystalline phase, have been found to undergo hydrolysis at the sugar-phosphate ester bond in spite of their natural inertness toward hydrolysis. Here, kinetics of the hydrolysis reaction and interactions between the lipid matrix and the mononucleotide adenosine 5'-monophosphate disodium salt (AMP) and its 2'-deoxy derivative (dAMP) are thoroughly investigated in order to shed some light on the mechanism of the nucleotide recognition and phosphate ester hydrolysis. Experiments evidenced that molecular recognition occurs essentially through the sn-2 and the sn-3 alcoholic OH groups of mono-olein. As deduced from the apparent activation energies, the mechanism underlying the hydrolysis reaction is the same for AMP and dAMP. Nevertheless, the reaction proceeds slower for the latter, highlighting a substantial difference in the chemical behavior of the two nucleotides. A model that explains the hydrolysis reaction is presented. Remarkably, the hydrolysis mechanism appears to be highly specific for the Ia3d phase.
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Affiliation(s)
- Sergio Murgia
- Department of Chemical Science, Cagliari University, CNBS and CSGI, ss 554, bivio Sestu, 09042 Monserrato (CA), Italy.
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19
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Tarrat N. Alkaline hydrolysis of phosphate triesters in solution: Stepwise or concerted? A theoretical study. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.theochem.2009.11.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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20
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Greig IR. The analysis of enzymic free energy relationships using kinetic and computational models. Chem Soc Rev 2010; 39:2272-301. [DOI: 10.1039/b902741f] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Kamerlin SCL, Haranczyk M, Warshel A. Are mixed explicit/implicit solvation models reliable for studying phosphate hydrolysis? A comparative study of continuum, explicit and mixed solvation models. Chemphyschem 2009; 10:1125-34. [PMID: 19301306 DOI: 10.1002/cphc.200800753] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Phosphate hydrolysis is ubiquitous in biology. However, despite intensive research on this class of reactions, the precise nature of the reaction mechanism remains controversial. Herein, we have examined the hydrolysis of three homologous phosphate diesters. The solvation free energy was simulated by means of either an implicit solvation model (COSMO), hybrid quantum mechanical/molecular mechanical free energy perturbation (QM/MM-FEP) or a mixed solvation model in which N water molecules were explicitly included in the ab initio description of the reacting system (where N=1-3), with the remainder of the solvent being implicitly modelled as a continuum. Here, both COSMO and QM/MM-FEP reproduce DeltaG(obs) within an error of about 1 kcal mol(-1). However, we demonstrate that in order to obtain any kind of reliable results from a mixed model, it is essential to carefully select the explicit water molecules from short QM/MM runs that act as a model for the true infinite system. Additionally, the mixed models tend to be increasingly unstable and miss larger entropic contributions as more explicit water molecules are placed into the system. Thus, our analysis indicates that this approach provides an unreliable way for modelling phosphate hydrolysis in solution.
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Affiliation(s)
- Shina C L Kamerlin
- Department of Chemistry, University of Southern California, 3620 McClintock Ave., Los Angeles, CA 90089, USA.
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Souza BS, Brandão TAS, Orth ES, Roma AC, Longo RL, Bunton CA, Nome F. Hydrolysis of 8-Quinolyl Phosphate Monoester: Kinetic and Theoretical Studies of the Effect of Lanthanide Ions. J Org Chem 2008; 74:1042-53. [DOI: 10.1021/jo801870v] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Bruno S. Souza
- Departamento de Química, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, 88040-900, Brazil, Departamento de Química Fundamental, Universidade Federal de Recife, Pernambuco, 50740-540, Brazil, and Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, 93106-9510
| | - Tiago A. S. Brandão
- Departamento de Química, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, 88040-900, Brazil, Departamento de Química Fundamental, Universidade Federal de Recife, Pernambuco, 50740-540, Brazil, and Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, 93106-9510
| | - Elisa S. Orth
- Departamento de Química, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, 88040-900, Brazil, Departamento de Química Fundamental, Universidade Federal de Recife, Pernambuco, 50740-540, Brazil, and Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, 93106-9510
| | - Ana C. Roma
- Departamento de Química, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, 88040-900, Brazil, Departamento de Química Fundamental, Universidade Federal de Recife, Pernambuco, 50740-540, Brazil, and Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, 93106-9510
| | - Ricardo L. Longo
- Departamento de Química, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, 88040-900, Brazil, Departamento de Química Fundamental, Universidade Federal de Recife, Pernambuco, 50740-540, Brazil, and Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, 93106-9510
| | - Clifford A. Bunton
- Departamento de Química, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, 88040-900, Brazil, Departamento de Química Fundamental, Universidade Federal de Recife, Pernambuco, 50740-540, Brazil, and Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, 93106-9510
| | - Faruk Nome
- Departamento de Química, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, 88040-900, Brazil, Departamento de Química Fundamental, Universidade Federal de Recife, Pernambuco, 50740-540, Brazil, and Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, 93106-9510
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van Bochove MA, Swart M, Bickelhaupt FM. Stepwise walden inversion in nucleophilic substitution at phosphorus. Phys Chem Chem Phys 2008; 11:259-67. [PMID: 19088981 DOI: 10.1039/b813152j] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have studied the mechanism of S(N)2@P reactions in the model systems X(-) + PMe(2)Y and X(-) + POR(2)Y (with R=Me, OH, OMe; and X, Y=Cl, OH, MeO) using density functional theory at OLYP/TZ2P. Our main purpose is to analyze the nature of the Walden inversion in our model nucleophilic substitution reactions. Walden inversion is well-known to proceed, in general, as a concerted umbrella motion of the substituents at the central atom. Interestingly, we find here that, in certain model reactions, Walden inversion can also proceed in a stepwise fashion in which the individual substituents of the umbrella flip, consecutively, from the educt to the product conformation via separate barriers on the reaction profile. We also examine how variation in nucleophile and leaving group may tune the pentavalent transition structure between labile transition state (TS) and stable transition complex (TC). Furthermore, we explore the various competing multistep pathways in the symmetric (X=Y) and asymmetric (X not equal Y) substitution reactions in our model reaction systems.
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Affiliation(s)
- Marc A van Bochove
- Department of Theoretical Chemistry and Amsterdam Center for Multiscale Modeling, Scheikundig Laboratorium der Vrije Universiteit, De Boelelaan 1083, NL-1081 HV Amsterdam, Netherlands
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Um IH, Han JY, Hwang SJ. Analysis of Linear Free-Energy Relationships Combined with Activation Parameters Assigns a Concerted Mechanism to Alkaline Hydrolysis of X-Substituted Phenyl Diphenylphosphinates. Chemistry 2008; 14:7324-30. [DOI: 10.1002/chem.200800553] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Rosta E, Kamerlin SCL, Warshel A. On the interpretation of the observed linear free energy relationship in phosphate hydrolysis: a thorough computational study of phosphate diester hydrolysis in solution. Biochemistry 2008; 47:3725-35. [PMID: 18307312 DOI: 10.1021/bi702106m] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The hydrolysis of phosphate esters is crucially important to biological systems, being involved in, among other things, signaling, energy transduction, biosynthesis, and the regulation of protein function. Despite this, there are many questions that remain unanswered in this important field, particularly with regard to the preferred mechanism of hydrolysis of phosphate esters, which can proceed through any of multiple pathways that are either associative or dissociative in nature. Previous comparisons of calculated and observed linear free energy relationships (LFERs) for phosphate monoester dianions with different leaving groups showed that the TS character gradually changes from associative to dissociative with the increasing acidity of the leaving group, while reproducing the experimental LFER. Here, we have generated ab initio potential energy surfaces for the hydrolysis of phosphate diesters in solution, with a variety of leaving groups. Once again, the reaction changes from a compact concerted pathway to one that is more expansive in character when the acidity of the leaving group increases. When such systems are examined in solution, it is essential to take into consideration the contribution of solute to the overall activation entropy, which remains a major computational challenge. The popular method of calculating the entropy using a quasi-harmonic approximation appears to markedly overestimate the configurational entropy for systems with multiple occupied energy wells. We introduce an improved restraint release approach for evaluating configurational entropies and apply this approach to our systems. We demonstrate that when this factor is taken into account, it is possible to reproduce the experimental LFER for this system with reasonable accuracy.
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Affiliation(s)
- Edina Rosta
- Department of Chemistry, University of Southern California, 3620 McClintock Avenue, Los Angeles, California 90089-1062, USA
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Iché-Tarrat N, Barthelat JC, Vigroux A. Theoretical study of specific hydrogen-bonding effects on the bridging P-OR bond strength of phosphate monoester dianions. J Phys Chem B 2008; 112:3217-21. [PMID: 18275186 DOI: 10.1021/jp710945w] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
It has been proposed that the driving force for the initial phosphoryl transfer step of protein tyrosine phosphatases (PTPases) could be activation of the substrate ROPO32- by means of an enforced hydrogen-bonding interaction between an aspartic general acid and the bridging oxygen atom O (Zhang et al. Biochemistry 1995, 34, 16088-16096). The potential catalytic effect of this type of interaction, with regard to P-OR bond cleavage, was investigated computationally through simple model systems in which an efficient intramolecular hydrogen bond can take place between a H-bond donor group and the bridging oxygen atom of the dianionic phosphate. The dielectric effect of the environment (epsilon = 1, 4, and 78) was also explored. The results indicate that this interaction causes significant lengthenings of the scissile P-OR bond in all media but with more extreme effects observed in the low dielectric fields epsilon = 1 and epsilon = 4. It is interesting that, in all cases examined, this interaction actually contributes to stabilize the reactant state while causing its P-OR bond to lengthen. Overall, our results support the idea that this specific hydrogen-bonding situation might well be used by PTPases as an important driving force for promoting phosphoryl transfer reactions through highly dissociative transition states.
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Affiliation(s)
- Nathalie Iché-Tarrat
- Laboratoire de Synthèse et Physico-Chimie de Molécules d'Intérêt Biologique, UMR 5068 CNRS, Université Paul Sabatier, Toulouse Cedex 9, France
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van Bochove MA, Bickelhaupt FM. Nucleophilic Substitution at C, Si and P: How Solvation Affects the Shape of Reaction Profiles. European J Org Chem 2008. [DOI: 10.1002/ejoc.200700953] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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van Bochove MA, Swart M, Bickelhaupt FM. Nucleophilic substitution at phosphorus centers (SN2@p). Chemphyschem 2008; 8:2452-63. [PMID: 17990249 DOI: 10.1002/cphc.200700488] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We have studied the characteristics of archetypal model systems for bimolecular nucleophilic substitution at phosphorus (SN2@P) and, for comparison, at carbon (SN2@C) and silicon (SN2@Si) centers. In our studies, we applied the generalized gradient approximation (GGA) of density functional theory (DFT) at the OLYP/TZ2P level. Our model systems cover nucleophilic substitution at carbon in X(-)+CH3Y (SN2@C), at silicon in X(-)+SiH3Y (SN2@Si), at tricoordinate phosphorus in X(-)+PH2Y (SN2@P3), and at tetracoordinate phosphorus in X(-)+POH2Y (SN2@P4). The main feature of going from SN2@C to SN2@P is the loss of the characteristic double-well potential energy surface (PES) involving a transition state [X--CH3--Y]- and the occurrence of a single-well PES with a stable transition complex, namely, [X--PH2--Y]- or [X--POH2--Y](-). The differences between SN2@P3 and SN2@P4 are relatively small. We explored both the symmetric and asymmetric (i.e. X, Y=Cl, OH) SN2 reactions in our model systems, the competition between backside and frontside pathways, and the dependence of the reactions on the conformation of the reactants. Furthermore, we studied the effect, on the symmetric and asymmetric SN2@P3 and S(N)2@P4 reactions, of replacing hydrogen substituents at the phosphorus centers by chlorine and fluorine in the model systems X(-)+PR2Y and X(-)+POR2Y, with R=Cl, F. An interesting phenomenon is the occurrence of a triple-well PES not only in the symmetric, but also in the asymmetric SN2@P4 reactions of X(-)+POCl2--Y.
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Affiliation(s)
- Marc A van Bochove
- Theoretische Chemie, Scheikundig Laboratorium der Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
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