1
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Baumann P, Jin Y. Far-reaching effects of tyrosine64 phosphorylation on Ras revealed with BeF 3- complexes. Commun Chem 2024; 7:19. [PMID: 38297137 PMCID: PMC10830474 DOI: 10.1038/s42004-024-01105-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 01/11/2024] [Indexed: 02/02/2024] Open
Abstract
Tyrosine phosphorylation on Ras by Src kinase is known to uncouple Ras from upstream regulation and downstream communication. However, the mechanisms by which phosphorylation modulates these interactions have not been detailed. Here, the major mono-phosphorylation level on tyrosine64 is quantified by 31P NMR and mutagenesis. Crystal structures of unphosphorylated and tyrosine64-phosphorylated Ras in complex with a BeF3- ground state analogue reveal "closed" Ras conformations very different from those of the "open" conformations previously observed for non-hydrolysable GTP analogue structures of Ras. They deliver new mechanistic and conformational insights into intrinsic GTP hydrolysis. Phosphorylation of tyrosine64 delivers conformational changes distant from the active site, showing why phosphorylated Ras has reduced affinity to its downstream effector Raf. 19F NMR provides evidence for changes in the intrinsic GTPase and nucleotide exchange rate and identifies the concurrent presence of a major "closed" conformation alongside a minor yet functionally important "open" conformation at the ground state of Ras. This study expands the application of metal fluoride complexes in revealing major and minor conformational changes of dynamic and modified Ras proteins.
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Affiliation(s)
- Patrick Baumann
- School of Chemistry, Cardiff University, Park Place, Cardiff, CF10 3AT, UK
- Department of Chemistry, School of Natural Sciences, Faculty of Science and Engineering, University of Manchester, M13 9PL, Manchester, UK
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - Yi Jin
- School of Chemistry, Cardiff University, Park Place, Cardiff, CF10 3AT, UK.
- Department of Chemistry, School of Natural Sciences, Faculty of Science and Engineering, University of Manchester, M13 9PL, Manchester, UK.
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
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2
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Li M, Wang Y, Fan J, Zhuang H, Liu Y, Ji D, Lu S. Mechanistic Insights into the Long-range Allosteric Regulation of KRAS Via Neurofibromatosis Type 1 (NF1) Scaffold Upon SPRED1 Loading. J Mol Biol 2022; 434:167730. [PMID: 35872068 DOI: 10.1016/j.jmb.2022.167730] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 06/22/2022] [Accepted: 07/08/2022] [Indexed: 01/17/2023]
Abstract
Allosteric regulation is the most direct and efficient way of regulating protein function, wherein proteins transmit the perturbations at one site to another distinct functional site. Deciphering the mechanism of allosteric regulation is of vital importance for the comprehension of both physiological and pathological events in vivo as well as the rational allosteric drug design. However, it remains challenging to elucidate dominant allosteric signal transduction pathways, especially for large and multi-component protein machineries where long-range allosteric regulation exits. One of the quintessential examples having long-range allosteric regulation is the ternary complex, SPRED1-RAS-neurofibromin type 1 (NF1, a RAS GTPase-activating protein), in which SPRED1 facilitates RAS-GTP hydrolysis by interacting with NF1 at a distal, allosteric site from the RAS binding site. To address the underlying mechanism, we performed extensive Gaussian accelerated molecular dynamics simulations and Markov state model analysis of KRAS-NF1 complex in the presence and absence of SPRED1. Our findings suggested that SPRED1 loading allosterically enhanced KRAS-NF1 binding, but hindered conformational transformation of the NF1 catalytic center for RAS hydrolysis. Moreover, we unveiled the possible allosteric pathways upon SPRED1 binding through difference contact network analysis. This study not only provided an in-depth mechanistic insight into the allosteric regulation of KRAS by SPRED1, but also shed light on the investigation of long-range allosteric regulation among complex macromolecular systems.
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Affiliation(s)
- Minyu Li
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China
| | - Yuanhao Wang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China
| | - Jigang Fan
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China
| | - Haiming Zhuang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China
| | - Yaqin Liu
- Medicinal Chemistry and Bioinformatics Center, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China
| | - Dong Ji
- Department of Anesthesiology, Changhai Hospital, Navy Medical University, Shanghai 200433, China.
| | - Shaoyong Lu
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China; Medicinal Chemistry and Bioinformatics Center, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China.
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3
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Laganowsky A, Clemmer DE, Russell DH. Variable-Temperature Native Mass Spectrometry for Studies of Protein Folding, Stabilities, Assembly, and Molecular Interactions. Annu Rev Biophys 2021; 51:63-77. [PMID: 34932911 PMCID: PMC9086101 DOI: 10.1146/annurev-biophys-102221-101121] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The structures and conformational dynamics of proteins, protein complexes, and their noncovalent interactions with other molecules are controlled specifically by the Gibbs free energy (entropy and enthalpy) of the system. For some organisms, temperature is highly regulated, but the majority of biophysical studies are carried out at room, nonphysiological temperature. In this review, we describe variable-temperature electrospray ionization (vT-ESI) mass spectrometry (MS)-based studies with unparalleled sensitivity, dynamic range, and selectivity for studies of both cold- and heat-induced chemical processes. Such studies provide direct determinations of stabilities, reactivities, and thermodynamic measurements for native and non-native structures of proteins and protein complexes and for protein-ligand interactions. Highlighted in this review are vT-ESI-MS studies that reveal 40 different conformers of chymotrypsin inhibitor 2, a classic two-state (native → unfolded) unfolder, and thermochemistry for a model membrane protein system binding lipid and its regulatory protein. Expected final online publication date for the Annual Review of Biophysics, Volume 51 is May 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Arthur Laganowsky
- Department of Chemistry, Texas A&M University, College Station, Texas, USA; ,
| | - David E Clemmer
- Department of Chemistry, Indiana University, Bloomington, Indiana, USA;
| | - David H Russell
- Department of Chemistry, Texas A&M University, College Station, Texas, USA; ,
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4
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Khrenova MG, Grigorenko BL, Nemukhin AV. Molecular Modeling Reveals the Mechanism of Ran-RanGAP-Catalyzed Guanosine Triphosphate Hydrolysis without an Arginine Finger. ACS Catal 2021. [DOI: 10.1021/acscatal.1c00582] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Maria G. Khrenova
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1/3, Moscow 119991, Russia
- Bach Institute of Biochemistry, Federal Research Centre “Fundamentals of Biotechnology”, Russian Academy of Sciences, Moscow 119071, Russia
| | - Bella L. Grigorenko
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1/3, Moscow 119991, Russia
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow 19334, Russia
| | - Alexander V. Nemukhin
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1/3, Moscow 119991, Russia
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow 19334, Russia
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5
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Grigorenko BL, Kots ED, Nemukhin AV. Diversity of mechanisms in Ras-GAP catalysis of guanosine triphosphate hydrolysis revealed by molecular modeling. Org Biomol Chem 2020; 17:4879-4891. [PMID: 31041977 DOI: 10.1039/c9ob00463g] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The mechanism of the deceptively simple reaction of guanosine triphosphate (GTP) hydrolysis catalyzed by the cellular protein Ras in complex with the activating protein GAP is an important issue because of the significance of this reaction in cancer research. We show that molecular modeling of GTP hydrolysis in the Ras-GAP active site reveals a diversity of mechanisms of the intrinsic chemical reaction depending on molecular groups at position 61 in Ras occupied by glutamine in the wild-type enzyme. First, a comparison of reaction energy profiles computed at the quantum mechanics/molecular mechanics (QM/MM) level shows that an assignment of the Gln61 side chain in the wild-type Ras either to QM or to MM parts leads to different scenarios corresponding to the glutamine-assisted or the substrate-assisted mechanisms. Second, replacement of Gln61 by the nitro-analog of glutamine (NGln) or by Glu, applied in experimental studies, results in two more scenarios featuring the so-called two-water and the concerted-type mechanisms. The glutamine-assisted mechanism in the wild-type Ras-GAP, in which the conserved Gln61 plays a decisive role, switching between the amide and imide tautomer forms, is consistent with the known experimental results of structural, kinetic and spectroscopy studies. The results emphasize the role of the Ras residue Gln61 in Ras-GAP catalysis and explain the retained catalytic activity of the Ras-GAP complex towards GTP hydrolysis in the Gln61NGln and Gln61Glu mutants of Ras.
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Affiliation(s)
- Bella L Grigorenko
- Department of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russia.
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6
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Moghadamchargari Z, Huddleston J, Shirzadeh M, Zheng X, Clemmer DE, M Raushel F, Russell DH, Laganowsky A. Intrinsic GTPase Activity of K-RAS Monitored by Native Mass Spectrometry. Biochemistry 2019; 58:3396-3405. [PMID: 31306575 DOI: 10.1021/acs.biochem.9b00532] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Mutations in RAS are associated with many different cancers and have been a therapeutic target for more than three decades. RAS cycles from an active to inactive state by both intrinsic and GTPase-activating protein (GAP)-stimulated hydrolysis. The activated enzyme interacts with downstream effectors, leading to tumor proliferation. Mutations in RAS associated with cancer are insensitive to GAP, and the rate of inactivation is limited to their intrinsic hydrolysis rate. Here, we use high-resolution native mass spectrometry (MS) to determine the kinetics and transition state thermodynamics of intrinsic hydrolysis for K-RAS and its oncogenic mutants. MS data reveal heterogeneity where both 2'-deoxy and 2'-hydroxy forms of GDP (guanosine diphosphate) and GTP (guanosine triphosphate) are bound to the recombinant enzyme. Intrinsic GTPase activity is directly monitored by the loss in mass of K-RAS bound to GTP, which corresponds to the release of phosphate. The rates determined from MS are in direct agreement with those measured using an established solution-based assay. Our results show that the transition state thermodynamics for the intrinsic GTPase activity of K-RAS is both enthalpically and entropically unfavorable. The oncogenic mutants G12C, Q61H, and G13D unexpectedly exhibit a 2'-deoxy GTP intrinsic hydrolysis rate higher than that for GTP.
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Affiliation(s)
- Zahra Moghadamchargari
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
| | - Jamison Huddleston
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
| | - Mehdi Shirzadeh
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
| | - Xueyun Zheng
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
| | - David E Clemmer
- Department of Chemistry , Indiana University , Bloomington , Indiana , 47405 , United States
| | - Frank M Raushel
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
| | - David H Russell
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
| | - Arthur Laganowsky
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
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7
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Lu S, Ni D, Wang C, He X, Lin H, Wang Z, Zhang J. Deactivation Pathway of Ras GTPase Underlies Conformational Substates as Targets for Drug Design. ACS Catal 2019. [DOI: 10.1021/acscatal.9b02556] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Shaoyong Lu
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Clinical and Fundamental Research Center, Department of Pharmacy, Renji Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai 200127, China
| | - Duan Ni
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Clinical and Fundamental Research Center, Department of Pharmacy, Renji Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai 200127, China
| | - Chengxiang Wang
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Clinical and Fundamental Research Center, Department of Pharmacy, Renji Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai 200127, China
| | - Xinheng He
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Clinical and Fundamental Research Center, Department of Pharmacy, Renji Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai 200127, China
| | - Houwen Lin
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Renji Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai 200127, China
| | - Zheng Wang
- Department of Gastrointestinal Surgery, Renji Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai 200127, China
| | - Jian Zhang
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Clinical and Fundamental Research Center, Department of Pharmacy, Renji Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai 200127, China
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8
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Calixto AR, Moreira C, Pabis A, Kötting C, Gerwert K, Rudack T, Kamerlin SCL. GTP Hydrolysis Without an Active Site Base: A Unifying Mechanism for Ras and Related GTPases. J Am Chem Soc 2019; 141:10684-10701. [PMID: 31199130 DOI: 10.1021/jacs.9b03193] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
GTP hydrolysis is a biologically crucial reaction, being involved in regulating almost all cellular processes. As a result, the enzymes that catalyze this reaction are among the most important drug targets. Despite their vital importance and decades of substantial research effort, the fundamental mechanism of enzyme-catalyzed GTP hydrolysis by GTPases remains highly controversial. Specifically, how do these regulatory proteins hydrolyze GTP without an obvious general base in the active site to activate the water molecule for nucleophilic attack? To answer this question, we perform empirical valence bond simulations of GTPase-catalyzed GTP hydrolysis, comparing solvent- and substrate-assisted pathways in three distinct GTPases, Ras, Rab, and the Gαi subunit of a heterotrimeric G-protein, both in the presence and in the absence of the corresponding GTPase activating proteins. Our results demonstrate that a general base is not needed in the active site, as the preferred mechanism for GTP hydrolysis is a conserved solvent-assisted pathway. This pathway involves the rate-limiting nucleophilic attack of a water molecule, leading to a short-lived intermediate that tautomerizes to form H2PO4- and GDP as the final products. Our fundamental biochemical insight into the enzymatic regulation of GTP hydrolysis not only resolves a decades-old mechanistic controversy but also has high relevance for drug discovery efforts. That is, revisiting the role of oncogenic mutants with respect to our mechanistic findings would pave the way for a new starting point to discover drugs for (so far) "undruggable" GTPases like Ras.
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Affiliation(s)
- Ana R Calixto
- Department of Chemistry-BMC , Uppsala University , Box 576, S-751 23 Uppsala , Sweden
| | - Cátia Moreira
- Department of Chemistry-BMC , Uppsala University , Box 576, S-751 23 Uppsala , Sweden
| | - Anna Pabis
- Department of Cell and Molecular Biology , Uppsala University , BMC Box 596, S-751 24 , Uppsala , Sweden
| | - Carsten Kötting
- Department of Biophysics , Ruhr University Bochum , 44801 Bochum , Germany
| | - Klaus Gerwert
- Department of Biophysics , Ruhr University Bochum , 44801 Bochum , Germany
| | - Till Rudack
- Department of Biophysics , Ruhr University Bochum , 44801 Bochum , Germany
| | - Shina C L Kamerlin
- Department of Chemistry-BMC , Uppsala University , Box 576, S-751 23 Uppsala , Sweden
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9
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Kulkarni Y, Kamerlin SCL. Computational physical organic chemistry using the empirical valence bond approach. ADVANCES IN PHYSICAL ORGANIC CHEMISTRY 2019. [DOI: 10.1016/bs.apoc.2019.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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10
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Roston D, Lu X, Fang D, Demapan D, Cui Q. Analysis of Phosphoryl-Transfer Enzymes with QM/MM Free Energy Simulations. Methods Enzymol 2018; 607:53-90. [PMID: 30149869 DOI: 10.1016/bs.mie.2018.05.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We discuss the application of quantum mechanics/molecular mechanics (QM/MM) free energy simulations to the analysis of phosphoryl transfers catalyzed by two enzymes: alkaline phosphatase and myosin. We focus on the nature of the transition state and the issue of mechanochemical coupling, respectively, in the two enzymes. The results illustrate unique insights that emerged from the QM/MM simulations, especially concerning the interpretation of experimental data regarding the nature of enzymatic transition states and coupling between global structural transition and catalysis in the active site. We also highlight a number of technical issues worthy of attention when applying QM/MM free energy simulations, and comment on a number of technical and mechanistic issues that require further studies.
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Affiliation(s)
- Daniel Roston
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin, Madison, Madison, WI, United States
| | - Xiya Lu
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin, Madison, Madison, WI, United States
| | - Dong Fang
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin, Madison, Madison, WI, United States
| | - Darren Demapan
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin, Madison, Madison, WI, United States
| | - Qiang Cui
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin, Madison, Madison, WI, United States.
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11
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Šponer J, Bussi G, Krepl M, Banáš P, Bottaro S, Cunha RA, Gil-Ley A, Pinamonti G, Poblete S, Jurečka P, Walter NG, Otyepka M. RNA Structural Dynamics As Captured by Molecular Simulations: A Comprehensive Overview. Chem Rev 2018; 118:4177-4338. [PMID: 29297679 PMCID: PMC5920944 DOI: 10.1021/acs.chemrev.7b00427] [Citation(s) in RCA: 357] [Impact Index Per Article: 59.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Indexed: 12/14/2022]
Abstract
With both catalytic and genetic functions, ribonucleic acid (RNA) is perhaps the most pluripotent chemical species in molecular biology, and its functions are intimately linked to its structure and dynamics. Computer simulations, and in particular atomistic molecular dynamics (MD), allow structural dynamics of biomolecular systems to be investigated with unprecedented temporal and spatial resolution. We here provide a comprehensive overview of the fast-developing field of MD simulations of RNA molecules. We begin with an in-depth, evaluatory coverage of the most fundamental methodological challenges that set the basis for the future development of the field, in particular, the current developments and inherent physical limitations of the atomistic force fields and the recent advances in a broad spectrum of enhanced sampling methods. We also survey the closely related field of coarse-grained modeling of RNA systems. After dealing with the methodological aspects, we provide an exhaustive overview of the available RNA simulation literature, ranging from studies of the smallest RNA oligonucleotides to investigations of the entire ribosome. Our review encompasses tetranucleotides, tetraloops, a number of small RNA motifs, A-helix RNA, kissing-loop complexes, the TAR RNA element, the decoding center and other important regions of the ribosome, as well as assorted others systems. Extended sections are devoted to RNA-ion interactions, ribozymes, riboswitches, and protein/RNA complexes. Our overview is written for as broad of an audience as possible, aiming to provide a much-needed interdisciplinary bridge between computation and experiment, together with a perspective on the future of the field.
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Affiliation(s)
- Jiří Šponer
- Institute of Biophysics of the Czech Academy of Sciences , Kralovopolska 135 , Brno 612 65 , Czech Republic
| | - Giovanni Bussi
- Scuola Internazionale Superiore di Studi Avanzati , Via Bonomea 265 , Trieste 34136 , Italy
| | - Miroslav Krepl
- Institute of Biophysics of the Czech Academy of Sciences , Kralovopolska 135 , Brno 612 65 , Czech Republic
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science , Palacky University Olomouc , 17. listopadu 12 , Olomouc 771 46 , Czech Republic
| | - Pavel Banáš
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science , Palacky University Olomouc , 17. listopadu 12 , Olomouc 771 46 , Czech Republic
| | - Sandro Bottaro
- Structural Biology and NMR Laboratory, Department of Biology , University of Copenhagen , Copenhagen 2200 , Denmark
| | - Richard A Cunha
- Scuola Internazionale Superiore di Studi Avanzati , Via Bonomea 265 , Trieste 34136 , Italy
| | - Alejandro Gil-Ley
- Scuola Internazionale Superiore di Studi Avanzati , Via Bonomea 265 , Trieste 34136 , Italy
| | - Giovanni Pinamonti
- Scuola Internazionale Superiore di Studi Avanzati , Via Bonomea 265 , Trieste 34136 , Italy
| | - Simón Poblete
- Scuola Internazionale Superiore di Studi Avanzati , Via Bonomea 265 , Trieste 34136 , Italy
| | - Petr Jurečka
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science , Palacky University Olomouc , 17. listopadu 12 , Olomouc 771 46 , Czech Republic
| | - Nils G Walter
- Single Molecule Analysis Group and Center for RNA Biomedicine, Department of Chemistry , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Michal Otyepka
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science , Palacky University Olomouc , 17. listopadu 12 , Olomouc 771 46 , Czech Republic
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12
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Li Y, Zhang Y, Großerüschkamp F, Stephan S, Cui Q, Kötting C, Xia F, Gerwert K. Specific Substates of Ras To Interact with GAPs and Effectors: Revealed by Theoretical Simulations and FTIR Experiments. J Phys Chem Lett 2018; 9:1312-1317. [PMID: 29488771 PMCID: PMC6692134 DOI: 10.1021/acs.jpclett.8b00342] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The oncogenic Ras protein adopts various specific conformational states to execute its function in signal transduction. The large number of Ras structures obtained from X-ray and NMR experiments illustrates the diverse conformations that Ras adopts. It is difficult, however, to connect specific structural features with Ras functions. We report the free-energy landscape of Ras·GTP based on extensive explicit solvent simulations. The free-energy map clearly shows that the functional state 2 of Ras·GTP in fact has two distinct substates, denoted here as "Tyr32in" and "Tyr32out". Unbiased MD simulations show that the two substrates interconvert on the submicrosecond scale in solution, pointing to a novel mechanism for Ras·GTP to selectively interact with GAPs and effectors. This proposal is further supported by time-resolved FTIR experiments, which demonstrate that Tyr32 destabilizes the Ras·GAP complex and facilitates an efficient termination of Ras signaling.
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Affiliation(s)
- Yang Li
- School of Chemistry and Molecular Engineering , East China Normal University , Shanghai 200062 , China
- School of Information Science and Engineering , Shandong Agricultural University , Taian 271018 , China
| | - Yuwei Zhang
- School of Chemistry and Molecular Engineering , East China Normal University , Shanghai 200062 , China
| | | | - Sara Stephan
- Department of Biophysics , Ruhr-University Bochum , ND 04 North , 44780 Bochum , Germany
| | - Qiang Cui
- Department of Chemistry and Theoretical Chemistry Institute , University of Wisconsin , 1101 University Avenue , Madison , Wisconsin 53706 , United States
| | - Carsten Kötting
- Department of Biophysics , Ruhr-University Bochum , ND 04 North , 44780 Bochum , Germany
| | - Fei Xia
- School of Chemistry and Molecular Engineering , East China Normal University , Shanghai 200062 , China
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai , Shanghai 200062 , China
| | - Klaus Gerwert
- Department of Biophysics , Ruhr-University Bochum , ND 04 North , 44780 Bochum , Germany
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13
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Abstract
Many cellular processes are controlled by GTPases, and gaining quantitative understanding of the activation of such processes has been a major challenge. In particular, it is crucial to obtain reliable free-energy surfaces for the relevant reaction paths both in solution and in GTPases active sites. Here, we revisit the energetics of the activation of EF-G and EF-Tu by the ribosome and explore the nature of the catalysis of the GTPase reaction. The comparison of EF-Tu to EF-G allows us to explore the impact of possible problems with the available structure of EF-Tu. Additionally, mutational effects are used for a careful validation of the emerging conclusions. It is found that the reaction may proceed by both a two-water mechanism and a one-water (GTP as a base) mechanism. However, in both cases, the activation involves a structural allosteric effect, which is likely to be a general-activation mechanism for all GTPases.
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14
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Purg M, Elias M, Kamerlin SCL. Similar Active Sites and Mechanisms Do Not Lead to Cross-Promiscuity in Organophosphate Hydrolysis: Implications for Biotherapeutic Engineering. J Am Chem Soc 2017; 139:17533-17546. [PMID: 29113434 PMCID: PMC5724027 DOI: 10.1021/jacs.7b09384] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Indexed: 01/27/2023]
Abstract
Organophosphate hydrolases are proficient catalysts of the breakdown of neurotoxic organophosphates and have great potential as both biotherapeutics for treating acute organophosphate toxicity and as bioremediation agents. However, proficient organophosphatases such as serum paraoxonase 1 (PON1) and the organophosphate-hydrolyzing lactonase SsoPox are unable to hydrolyze bulkyorganophosphates with challenging leaving groups such as diisopropyl fluorophosphate (DFP) or venomous agent X, creating a major challenge for enzyme design. Curiously, despite their mutually exclusive substrate specificities, PON1 and diisopropyl fluorophosphatase (DFPase) have essentially identical active sites and tertiary structures. In the present work, we use empirical valence bond simulations to probe the catalytic mechanism of DFPase as well as temperature, pH, and mutational effects, demonstrating that DFPase and PON1 also likely utilize identical catalytic mechanisms to hydrolyze their respective substrates. However, detailed examination of both static structures and dynamical simulations demonstrates subtle but significant differences in the electrostatic properties and solvent penetration of the two active sites and, most critically, the role of residues that make no direct contact with either substrate in acting as "specificity switches" between the two enzymes. Specifically, we demonstrate that key residues that are structurally and functionally critical for the paraoxonase activity of PON1 prevent it from being able to hydrolyze DFP with its fluoride leaving group. These insights expand our understanding of the drivers of the evolution of divergent substrate specificity in enzymes with identical active sites and guide the future design of organophosphate hydrolases that hydrolyze compounds with challenging leaving groups.
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Affiliation(s)
- Miha Purg
- Science for Life
Laboratory, Department of Cell and Molecular Biology, Uppsala University, BMC Box 596, S-751 24 Uppsala, Sweden
| | - Mikael Elias
- Department of Biochemistry, Molecular Biology and Biophysics &
Biotechnology Institute, University of Minnesota, 1479 Gortner Avenue, St. Paul, Minnesota 55108, United States
| | - Shina Caroline Lynn Kamerlin
- Science for Life
Laboratory, Department of Cell and Molecular Biology, Uppsala University, BMC Box 596, S-751 24 Uppsala, Sweden
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15
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Das S. Importance of an Orchestrate Participation of each Individual Residue Present at a Catalytic Site. Mol Inform 2017; 37:e1700105. [PMID: 29024508 DOI: 10.1002/minf.201700105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 09/27/2017] [Indexed: 12/23/2022]
Abstract
GTP hydrolysis is indispensable to keep a living cell healthy. Nature has evolved so many enzymes to enhance the slow GTP hydrolysis. Rab GTPases are evolved to regulate vesicle trafficking. GTPase activating proteins (GAPs) accelerates their intrinsic slow GTP hydrolysis in order to maintain the sustainability between cellular events. Any malfunction/interference in this hydrolysis disrupts normal cellular events and causes severe diseases. In this study, GTP hydrolysis mechanism of Rab33B catalyzed by TBC-domain GAP protein Gyp1p has been decoded using extensive ab initio QM/MM metadynamics simulations. An organized coupled movement of individual residues present at the catalytic site is found to be the key factor for this reaction. An unorganized coupled movement leads the hydrolysis through very high energy pathways. This also reveals that the chemical transformations occurring at a catalytic site are residue specific.
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Affiliation(s)
- Santanu Das
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal By-pass Road, Bhauri, Bhopal, 462066, MP, India
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16
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Bordes I, Castillo R, Moliner V. Theoretical Study of the Phosphoryl Transfer Reaction from ATP to Dha Catalyzed by DhaK from Escherichia coli. J Phys Chem B 2017; 121:8878-8892. [PMID: 28850238 DOI: 10.1021/acs.jpcb.7b04862] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Protein kinases, representing one of the largest protein families involved in almost all aspects of cell life, have become one of the most important targets for the development of new drugs to be used in, for instance, cancer treatments. In this article an exhaustive theoretical study of the phosphoryl transfer reaction from adenosine triphosphate (ATP) to dihydroxyacetone (Dha) catalyzed by DhaK from Escherichia coli (E. coli) is reported. Two different mechanisms, previously proposed for the phosphoryl transfer from ATP to the hydroxyl side chain of specific serine, threonine, or tyrosine residues, have been explored based on the generation of free energy surfaces (FES) computed with hybrid QM/MM potentials. The results suggest that the substrate-assisted phosphoryl and proton-transfer mechanism is kinetically more favorable than the mechanism where an aspartate would be activating the Dha. Although the details of the mechanisms appear to be dramatically dependent on the level of theory employed in the calculations (PM3/MM, B3LYP:PM3/MM, or B3LYP/MM), the transition states (TSs) for the phosphoryl transfer step appear to be described as a concerted step with different degrees of synchronicity in the breaking and forming bonds process in both explored mechanisms. Residues of the active site belonging to different subunits of the protein, such as Gly78B, Thr79A, Ser80A, Arg178B, and one Mg2+ cation, would be stabilizing the transferred phosphate in the TS. Asp109A would have a structural role by posing the Dha and other residues of the active site in the proper orientation. The information derived from our calculations not only reveals the role of the enzyme and the particular residues of its active site, but it can assist in the rational design of new more specific inhibitors.
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Affiliation(s)
- I Bordes
- Departament de Química Física i Analítica, Universitat Jaume I , 12071 Castellón, Spain
| | - R Castillo
- Departament de Química Física i Analítica, Universitat Jaume I , 12071 Castellón, Spain
| | - V Moliner
- Departament de Química Física i Analítica, Universitat Jaume I , 12071 Castellón, Spain.,Department of Chemistry, University of Bath , Bath BA2 7AY, United Kingdom
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17
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Abstract
The main problem for enzymes from psychrophilic species, which need to work near the freezing point of liquid water, is the exponential decay of reaction rates as the temperature is decreased. Cold-adapted enzymes have solved this problem by shifting the activation enthalpy-entropy balance for the catalyzed reaction compared to those of their mesophilic orthologs. To understand the structural basis of this universal feature, it is necessary to examine pairs of such orthologous enzymes, with known three-dimensional structures, at the microscopic level. Here, we use molecular dynamics free energy calculations in combination with the empirical valence bond method to evaluate the temperature dependence of the activation free energy for differently adapted triosephosphate isomerases. The results show that the enzyme from the psychrophilic bacterium Vibrio marinus indeed displays the characteristic shift in enthalpy-entropy balance, compared to that of the yeast ortholog. The origin of this effect is found to be located in a few surface-exposed protein loops that show differential mobilities in the two enzymes. Key mutations render these loops more mobile in the cold-adapted triosephosphate isomerase, which explains both the reduced activation enthalpy contribution from the protein surface and the lower thermostability.
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Affiliation(s)
- Johan Åqvist
- Department of Cell and Molecular Biology, Biomedical Center, Uppsala University , Box 596, SE-751 24 Uppsala, Sweden
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18
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19
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Cui Q. Perspective: Quantum mechanical methods in biochemistry and biophysics. J Chem Phys 2017; 145:140901. [PMID: 27782516 DOI: 10.1063/1.4964410] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
In this perspective article, I discuss several research topics relevant to quantum mechanical (QM) methods in biophysical and biochemical applications. Due to the immense complexity of biological problems, the key is to develop methods that are able to strike the proper balance of computational efficiency and accuracy for the problem of interest. Therefore, in addition to the development of novel ab initio and density functional theory based QM methods for the study of reactive events that involve complex motifs such as transition metal clusters in metalloenzymes, it is equally important to develop inexpensive QM methods and advanced classical or quantal force fields to describe different physicochemical properties of biomolecules and their behaviors in complex environments. Maintaining a solid connection of these more approximate methods with rigorous QM methods is essential to their transferability and robustness. Comparison to diverse experimental observables helps validate computational models and mechanistic hypotheses as well as driving further development of computational methodologies.
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Affiliation(s)
- Qiang Cui
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA
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20
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Lu X, Ovchinnikov V, Demapan D, Roston D, Cui Q. Regulation and Plasticity of Catalysis in Enzymes: Insights from Analysis of Mechanochemical Coupling in Myosin. Biochemistry 2017; 56:1482-1497. [PMID: 28225609 DOI: 10.1021/acs.biochem.7b00016] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The mechanism of ATP hydrolysis in the myosin motor domain is analyzed using a combination of DFTB3/CHARMM simulations and enhanced sampling techniques. The motor domain is modeled in the pre-powerstroke state, in the post-rigor state, and as a hybrid based on the post-rigor state with a closed nucleotide-binding pocket. The ATP hydrolysis activity is found to depend on the positioning of nearby water molecules, and a network of polar residues facilitates proton transfer and charge redistribution during hydrolysis. Comparison of the observed hydrolysis pathways and the corresponding free energy profiles leads to detailed models for the mechanism of ATP hydrolysis in the pre-powerstroke state and proposes factors that regulate the hydrolysis activity in different conformational states. In the pre-powerstroke state, the scissile Pγ-O3β bond breaks early in the reaction. Proton transfer from the lytic water to the γ-phosphate through active site residues is an important part of the kinetic bottleneck; several hydrolysis pathways that feature distinct proton transfer routes are found to have similar free energy barriers, suggesting a significant degree of plasticity in the hydrolysis mechanism. Comparison of hydrolysis in the pre-powerstroke state and the closed post-rigor model suggests that optimization of residues beyond the active site for electrostatic stabilization and preorganization is likely important to enzyme design.
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Affiliation(s)
- Xiya Lu
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Victor Ovchinnikov
- Department of Chemistry and Chemical Biology, Harvard University , 12 Oxford Street, Boston, Massachusetts 02138, United States
| | - Darren Demapan
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Daniel Roston
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Qiang Cui
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States
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21
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Abstract
The role played by entropy for the enormous rate enhancement achieved by enzymes has been debated for many decades. There are, for example, several confirmed cases where the activation free energy is reduced by around 10 kcal/mol due to entropic effects, corresponding to a rate enhancement of ∼107 compared to the uncatalyzed reaction. However, despite substantial efforts from both the experimental and theoretical side, no real consensus has been reached regarding the origin of such large entropic contributions to enzyme catalysis. Another remarkable instance of entropic effects is found in enzymes that are adapted by evolution to work at low temperatures, near the freezing point of water. These cold-adapted enzymes invariably show a more negative entropy and a lower enthalpy of activation than their mesophilic orthologs, which counteracts the exponential damping of reaction rates at lower temperature. The structural origin of this universal phenomenon has, however, remained elusive. The basic problem with connecting macroscopic thermodynamic quantities, such as activation entropy and enthalpy derived from Arrhenius plots, to the 3D protein structure is that the underlying detailed (microscopic) energetics is essentially inaccessible to experiment. Moreover, attempts to calculate entropy contributions by computer simulations have mostly focused only on substrate entropies, which do not provide the full picture. We have recently devised a new approach for accessing thermodynamic activation parameters of both enzyme and solution reactions from computer simulations, which turns out to be very successful. This method is analogous to the experimental Arrhenius plots and directly evaluates the temperature dependence of calculated reaction free energy profiles. Hence, by extensive molecular dynamics simulations and calculations of up to thousands of independent free energy profiles, we are able to extract activation parameters with sufficient precision for making direct comparisons to experiment. We show here that the agreement with the measured quantities, for both enzyme catalyzed and spontaneous solution reactions, is quite remarkable. Importantly, we can now address some of the most spectacular entropy effects in enzymes and clarify their detailed microscopic origin. Herein, we discuss as examples the conversion of cytidine to uridine catalyzed by cytidine deaminase and reactions taking place on the ribosome, namely, peptide bond formation and GTP hydrolysis by elongation factor Tu. It turns out that the large entropy contributions to catalysis in these cases can now be rationalized by our computational approach. Finally, we address the problem of cold adaptation of enzyme reaction rates and prove by computational experiments that the universal activation enthalpy-entropy phenomenon originates from mechanical properties of the outer protein surface.
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Affiliation(s)
- Johan Åqvist
- Department
of Cell and Molecular Biology, Uppsala University, Biomedical Center, Box 596, SE-751 24 Uppsala, Sweden
| | - Masoud Kazemi
- Department
of Cell and Molecular Biology, Uppsala University, Biomedical Center, Box 596, SE-751 24 Uppsala, Sweden
| | - Geir Villy Isaksen
- Department
of Cell and Molecular Biology, Uppsala University, Biomedical Center, Box 596, SE-751 24 Uppsala, Sweden
- The
Centre for Theoretical Computational Chemistry, Department of Chemistry, University of Tromsø, N9037 Tromsø, Norway
| | - Bjørn Olav Brandsdal
- The
Centre for Theoretical Computational Chemistry, Department of Chemistry, University of Tromsø, N9037 Tromsø, Norway
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22
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Romero-Rivera A, Garcia-Borràs M, Osuna S. Computational tools for the evaluation of laboratory-engineered biocatalysts. Chem Commun (Camb) 2016; 53:284-297. [PMID: 27812570 PMCID: PMC5310519 DOI: 10.1039/c6cc06055b] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 09/06/2016] [Indexed: 12/18/2022]
Abstract
Biocatalysis is based on the application of natural catalysts for new purposes, for which enzymes were not designed. Although the first examples of biocatalysis were reported more than a century ago, biocatalysis was revolutionized after the discovery of an in vitro version of Darwinian evolution called Directed Evolution (DE). Despite the recent advances in the field, major challenges remain to be addressed. Currently, the best experimental approach consists of creating multiple mutations simultaneously while limiting the choices using statistical methods. Still, tens of thousands of variants need to be tested experimentally, and little information is available on how these mutations lead to enhanced enzyme proficiency. This review aims to provide a brief description of the available computational techniques to unveil the molecular basis of improved catalysis achieved by DE. An overview of the strengths and weaknesses of current computational strategies is explored with some recent representative examples. The understanding of how this powerful technique is able to obtain highly active variants is important for the future development of more robust computational methods to predict amino-acid changes needed for activity.
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Affiliation(s)
- Adrian Romero-Rivera
- Institut de Química Computacional i Catàlisi and Departament de Química Universitat de Girona, Campus Montilivi, 17071 Girona, Catalonia, Spain.
| | - Marc Garcia-Borràs
- Department of Chemistry and Biochemistry, University of California, 607 Charles E. Young Drive, Los Angeles, California 90095, USA
| | - Sílvia Osuna
- Institut de Química Computacional i Catàlisi and Departament de Química Universitat de Girona, Campus Montilivi, 17071 Girona, Catalonia, Spain.
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