1
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Li T, Motta S, He Y. Deciphering the Mystery in p300 Taz2-p53 TAD2 Recognition. J Chem Theory Comput 2024. [PMID: 39141804 DOI: 10.1021/acs.jctc.4c00541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/16/2024]
Abstract
Intrinsically disordered proteins (IDPs) engage in various fundamental biological activities, and their behavior is of particular importance for a better understanding of the verbose but well-organized signal transduction in cells. IDPs exhibit uniquely paradoxical features with low affinity but simultaneously high specificity in recognizing their binding targets. The transcription factor p53 plays a crucial role in cancer suppression, carrying out some of its biological functions using its disordered regions, such as N-terminal transactivation domain 2 (TAD2). Exploration of the binding and unbinding processes between proteins is challenging, and the inherently disordered properties of these regions further complicate the issue. Computer simulations are a powerful tool to complement the experiments to fill gaps to explore the binding/unbinding processes between proteins. Here, we investigated the binding mechanism between p300 Taz2 and p53 TAD2 through extensive molecular dynamics (MD) simulations using the physics-based UNited RESidue (UNRES) force field with additional Go̅-like potentials. Distance restraints extracted from the NMR-resolved structures were imposed on intermolecular residue pairs to accelerate binding simulations, in which Taz2 was immobilized in a native-like conformation and disordered TAD2 was fully free. Starting from six structures with TAD2 placed at different positions around Taz2, we observed a metastable intermediate state in which the middle helical segment of TAD2 is anchored in the binding pocket, highlighting the significance of the TAD2 helix in directing protein recognition. Physics-based binding simulations show that successful binding is achieved after a series of stages, including (1) protein collisions to initiate the formation of encounter complexes, (2) partial attachment of TAD2, and finally (3) full attachment of TAD2 to the correct binding pocket of Taz2. Furthermore, machine-learning-based PathDetect-SOM was used to identify two binding pathways, the encounter complexes, and the intermediate states.
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Affiliation(s)
- Tongtong Li
- Department of Chemistry & Chemical Biology, The University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Stefano Motta
- Department of Earth and Environmental Sciences, University of Milano-Bicocca, Milan 20126, Italy
| | - Yi He
- Department of Chemistry & Chemical Biology, The University of New Mexico, Albuquerque, New Mexico 87131, United States
- Translational Informatics Division, Department of Internal Medicine, The University of New Mexico, Albuquerque, New Mexico 87131, United States
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2
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Schnettler JD, Wang MS, Gantz M, Bunzel HA, Karas C, Hollfelder F, Hecht MH. Selection of a promiscuous minimalist cAMP phosphodiesterase from a library of de novo designed proteins. Nat Chem 2024; 16:1200-1208. [PMID: 38702405 PMCID: PMC11230910 DOI: 10.1038/s41557-024-01490-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 02/27/2024] [Indexed: 05/06/2024]
Abstract
The ability of unevolved amino acid sequences to become biological catalysts was key to the emergence of life on Earth. However, billions of years of evolution separate complex modern enzymes from their simpler early ancestors. To probe how unevolved sequences can develop new functions, we use ultrahigh-throughput droplet microfluidics to screen for phosphoesterase activity amidst a library of more than one million sequences based on a de novo designed 4-helix bundle. Characterization of hits revealed that acquisition of function involved a large jump in sequence space enriching for truncations that removed >40% of the protein chain. Biophysical characterization of a catalytically active truncated protein revealed that it dimerizes into an α-helical structure, with the gain of function accompanied by increased structural dynamics. The identified phosphodiesterase is a manganese-dependent metalloenzyme that hydrolyses a range of phosphodiesters. It is most active towards cyclic AMP, with a rate acceleration of ~109 and a catalytic proficiency of >1014 M-1, comparable to larger enzymes shaped by billions of years of evolution.
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Affiliation(s)
| | - Michael S Wang
- Department of Chemistry, Princeton University, Princeton, USA
| | - Maximilian Gantz
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - H Adrian Bunzel
- Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
| | - Christina Karas
- Department of Molecular Biology, Princeton University, Princeton, USA
| | | | - Michael H Hecht
- Department of Chemistry, Princeton University, Princeton, USA.
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3
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Chang CWM, Wang SC, Wang CH, Pang AH, Yang CH, Chang YK, Wu WJ, Tsai MD. A unified view on enzyme catalysis by cryo-EM study of a DNA topoisomerase. Commun Chem 2024; 7:45. [PMID: 38418525 PMCID: PMC10901890 DOI: 10.1038/s42004-024-01129-y] [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: 12/18/2023] [Accepted: 02/14/2024] [Indexed: 03/01/2024] Open
Abstract
The theories for substrate recognition in enzyme catalysis have evolved from lock-key to induced fit, then conformational selection, and conformational selection followed by induced fit. However, the prevalence and consensus of these theories require further examination. Here we use cryogenic electron microscopy and African swine fever virus type 2 topoisomerase (AsfvTop2) to demonstrate substrate binding theories in a joint and ordered manner: catalytic selection by the enzyme, conformational selection by the substrates, then induced fit. The apo-AsfvTop2 pre-exists in six conformers that comply with the two-gate mechanism directing DNA passage and release in the Top2 catalytic cycle. The structures of AsfvTop2-DNA-inhibitor complexes show that substantial induced-fit changes occur locally from the closed apo-conformer that however is too far-fetched for the open apo-conformer. Furthermore, the ATPase domain of AsfvTop2 in the MgAMP-PNP-bound crystal structures coexist in reduced and oxidized forms involving a disulfide bond, which can regulate the AsfvTop2 function.
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Affiliation(s)
- Chiung-Wen Mary Chang
- Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan
- Institute of Biochemistry and Molecular Biology, China Medical University, Taichung, Taiwan
| | - Shun-Chang Wang
- Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan
| | - Chun-Hsiung Wang
- Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan
| | - Allan H Pang
- Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Cheng-Han Yang
- Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan
| | - Yao-Kai Chang
- Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan
| | - Wen-Jin Wu
- Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan
| | - Ming-Daw Tsai
- Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan.
- Institute of Biochemical Sciences, National Taiwan University, Taipei, 106, Taiwan.
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4
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Nam K, Shao Y, Major DT, Wolf-Watz M. Perspectives on Computational Enzyme Modeling: From Mechanisms to Design and Drug Development. ACS OMEGA 2024; 9:7393-7412. [PMID: 38405524 PMCID: PMC10883025 DOI: 10.1021/acsomega.3c09084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 01/15/2024] [Accepted: 01/19/2024] [Indexed: 02/27/2024]
Abstract
Understanding enzyme mechanisms is essential for unraveling the complex molecular machinery of life. In this review, we survey the field of computational enzymology, highlighting key principles governing enzyme mechanisms and discussing ongoing challenges and promising advances. Over the years, computer simulations have become indispensable in the study of enzyme mechanisms, with the integration of experimental and computational exploration now established as a holistic approach to gain deep insights into enzymatic catalysis. Numerous studies have demonstrated the power of computer simulations in characterizing reaction pathways, transition states, substrate selectivity, product distribution, and dynamic conformational changes for various enzymes. Nevertheless, significant challenges remain in investigating the mechanisms of complex multistep reactions, large-scale conformational changes, and allosteric regulation. Beyond mechanistic studies, computational enzyme modeling has emerged as an essential tool for computer-aided enzyme design and the rational discovery of covalent drugs for targeted therapies. Overall, enzyme design/engineering and covalent drug development can greatly benefit from our understanding of the detailed mechanisms of enzymes, such as protein dynamics, entropy contributions, and allostery, as revealed by computational studies. Such a convergence of different research approaches is expected to continue, creating synergies in enzyme research. This review, by outlining the ever-expanding field of enzyme research, aims to provide guidance for future research directions and facilitate new developments in this important and evolving field.
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Affiliation(s)
- Kwangho Nam
- Department
of Chemistry and Biochemistry, University
of Texas at Arlington, Arlington, Texas 76019, United States
| | - Yihan Shao
- Department
of Chemistry and Biochemistry, University
of Oklahoma, Norman, Oklahoma 73019-5251, United States
| | - Dan T. Major
- Department
of Chemistry and Institute for Nanotechnology & Advanced Materials, Bar-Ilan University, Ramat-Gan 52900, Israel
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5
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Borsley S, Gallagher JM, Leigh DA, Roberts BMW. Ratcheting synthesis. Nat Rev Chem 2024; 8:8-29. [PMID: 38102412 DOI: 10.1038/s41570-023-00558-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2023] [Indexed: 12/17/2023]
Abstract
Synthetic chemistry has traditionally relied on reactions between reactants of high chemical potential and transformations that proceed energetically downhill to either a global or local minimum (thermodynamic or kinetic control). Catalysts can be used to manipulate kinetic control, lowering activation energies to influence reaction outcomes. However, such chemistry is still constrained by the shape of one-dimensional reaction coordinates. Coupling synthesis to an orthogonal energy input can allow ratcheting of chemical reaction outcomes, reminiscent of the ways that molecular machines ratchet random thermal motion to bias conformational dynamics. This fundamentally distinct approach to synthesis allows multi-dimensional potential energy surfaces to be navigated, enabling reaction outcomes that cannot be achieved under conventional kinetic or thermodynamic control. In this Review, we discuss how ratcheted synthesis is ubiquitous throughout biology and consider how chemists might harness ratchet mechanisms to accelerate catalysis, drive chemical reactions uphill and programme complex reaction sequences.
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Affiliation(s)
- Stefan Borsley
- Department of Chemistry, University of Manchester, Manchester, UK
| | | | - David A Leigh
- Department of Chemistry, University of Manchester, Manchester, UK.
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6
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Li W, Kohne M, Warncke K. Reactivity Tracking of an Enzyme Progress Coordinate. J Phys Chem Lett 2023; 14:7157-7164. [PMID: 37540029 PMCID: PMC10440813 DOI: 10.1021/acs.jpclett.3c01464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Accepted: 07/26/2023] [Indexed: 08/05/2023]
Abstract
The reactivity of individual solvent-coupled protein configurations is used to track and resolve the progress coordinate for the core reaction sequence of substrate radical rearrangement and hydrogen atom transfer in the ethanolamine ammonia-lyase (EAL) enzyme from Salmonella enterica. The first-order decay of the substrate radical intermediate is the monitored reaction. Heterogeneous confinement from sucrose hydrates in the mesophase solvent surrounding the cryotrapped protein introduces distributed kinetics in the non-native decay of the substrate radical pair capture substate, which arise from an ensemble of configurational microstates. Reaction rates increase by >103-fold across the distribution to approach that for the native enabled substate for radical rearrangement, which reacts with monotonic kinetics. The native progress coordinate thus involves a collapse of the configuration space to generate optimized reactivity. Reactivity tracking reveals fundamental features of solvent-protein-reaction configurational coupling and leads to a model that refines the ensemble paradigm of enzyme catalysis for strongly adiabatic chemical steps.
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Affiliation(s)
- Wei Li
- Department
of Physics, Emory University, Atlanta, Georgia 30322, United States
| | - Meghan Kohne
- Department
of Physics, Emory University, Atlanta, Georgia 30322, United States
| | - Kurt Warncke
- Department
of Physics, Emory University, Atlanta, Georgia 30322, United States
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7
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Escobedo N, Monzon AM, Fornasari MS, Palopoli N, Parisi G. Combining Protein Conformational Diversity and Phylogenetic Information Using CoDNaS and CoDNaS-Q. Curr Protoc 2023; 3:e764. [PMID: 37184204 DOI: 10.1002/cpz1.764] [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] [Indexed: 05/16/2023]
Abstract
CoDNaS (http://ufq.unq.edu.ar/codnas/) and CoDNaS-Q (http://ufq.unq.edu.ar/codnasq) are repositories of proteins with different degrees of conformational diversity. Following the ensemble nature of the native state, conformational diversity represents the structural differences between the conformers in the ensemble. Each entry in CoDNaS and CoDNaS-Q contains a redundant collection of experimentally determined conformers obtained under different conditions. These conformers represent snapshots of the protein dynamism. While CoDNaS contains examples of conformational diversity at the tertiary level, a recent development, CoDNaS-Q, contains examples at the quaternary level. In the emerging age of accurate protein structure prediction by machine learning approaches, many questions remain open regarding the characterization of protein dynamism. In this context, most bioinformatics resources take advantage of distinct features derived from protein alignments, however, the complexity and heterogeneity of information makes it difficult to recover reliable biological signatures. Here we present five protocols to explore tertiary and quaternary conformational diversity at the individual protein level as well as for the characterization of the distribution of conformational diversity at the protein family level in a phylogenetic context. These protocols can provide curated protein families with experimentally known conformational diversity, facilitating the exploration of sequence determinants of protein dynamism. © 2023 Wiley Periodicals LLC. Basic Protocol 1: Assessing conformational diversity with CoDNaS Alternate Protocol 1: Assessing conformational diversity at the quaternary level with CoDNaS-Q Basic Protocol 2: Exploring conformational diversity in a protein family Alternate Protocol 2: Exploring quaternary conformational diversity in a protein family Basic Protocol 3: Representing conformational diversity in a phylogenetic context.
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Affiliation(s)
- Nahuel Escobedo
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | | | - María Silvina Fornasari
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Nicolas Palopoli
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Gustavo Parisi
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
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8
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Klinman JP. Dynamical activation of function in metalloenzymes. FEBS Lett 2023; 597:79-91. [PMID: 36239559 PMCID: PMC9839491 DOI: 10.1002/1873-3468.14515] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/27/2022] [Accepted: 09/29/2022] [Indexed: 01/17/2023]
Abstract
Formulations of hydrogen tunneling in enzyme-catalysed C-H activation reactions indicate enthalpic barriers to reaction that are independent of chemical steps and dependent on the protein scaffold. A tool to identify catalytically relevant site-specific protein thermal networks has emerged from temperature-dependent hydrogen deuterium exchange (TDHDX). Focusing on mutant enzyme forms with altered activation energies for catalysis, TDHDX provides a comparative analysis of the impact of mutation on Ea for local protein unfolding. Identified thermal networks appear unrelated to protein scaffold conservation and track to the dictates of the catalysed reaction, including sites for metal binding. The positions of thermal networks provide a framework for further understanding of time-dependent, functionally relevant protein motions. Measurement of nanosecond Stokes shifts at the surface of the thermal network in soybean lipoxygenase yields activation energies that are identical to Ea values measured for kcat . This finding identifies a rapid (> nanosecond), long-range and cooperative structural reorganization as the thermal barrier to catalysis. A model for protein dynamics is put forward that integrates broadly distributed protein conformational sampling with protein embedded thermal networks.
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Affiliation(s)
- Judith P. Klinman
- Department of Chemistry, University of California, Berkeley, Berkeley, California, 94720, United States
- California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, California, 94720, United States
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California, 94720, United States
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9
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Structure-Based Function and Regulation of NCX Variants: Updates and Challenges. Int J Mol Sci 2022; 24:ijms24010061. [PMID: 36613523 PMCID: PMC9820601 DOI: 10.3390/ijms24010061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 12/14/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022] Open
Abstract
The plasma-membrane homeostasis Na+/Ca2+ exchangers (NCXs) mediate Ca2+ extrusion/entry to dynamically shape Ca2+ signaling/in biological systems ranging from bacteria to humans. The NCX gene orthologs, isoforms, and their splice variants are expressed in a tissue-specific manner and exhibit nearly 104-fold differences in the transport rates and regulatory specificities to match the cell-specific requirements. Selective pharmacological targeting of NCX variants could benefit many clinical applications, although this intervention remains challenging, mainly because a full-size structure of eukaryotic NCX is unavailable. The crystal structure of the archaeal NCX_Mj, in conjunction with biophysical, computational, and functional analyses, provided a breakthrough in resolving the ion transport mechanisms. However, NCX_Mj (whose size is nearly three times smaller than that of mammalian NCXs) cannot serve as a structure-dynamic model for imitating high transport rates and regulatory modules possessed by eukaryotic NCXs. The crystal structures of isolated regulatory domains (obtained from eukaryotic NCXs) and their biophysical analyses by SAXS, NMR, FRET, and HDX-MS approaches revealed structure-based variances of regulatory modules. Despite these achievements, it remains unclear how multi-domain interactions can decode and integrate diverse allosteric signals, thereby yielding distinct regulatory outcomes in a given ortholog/isoform/splice variant. This article summarizes the relevant issues from the perspective of future developments.
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10
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Gao S, Zhang W, Barrow SL, Iavarone AT, Klinman JP. Temperature-dependent hydrogen deuterium exchange shows impact of analog binding on adenosine deaminase flexibility but not embedded thermal networks. J Biol Chem 2022; 298:102350. [PMID: 35933011 PMCID: PMC9483566 DOI: 10.1016/j.jbc.2022.102350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 07/28/2022] [Accepted: 07/29/2022] [Indexed: 11/29/2022] Open
Abstract
The analysis of hydrogen deuterium exchange by mass spectrometry as a function of temperature and mutation has emerged as a generic and efficient tool for the spatial resolution of protein networks that are proposed to function in the thermal activation of catalysis. In this work, we extend temperature-dependent hydrogen deuterium exchange from apo-enzyme structures to protein-ligand complexes. Using adenosine deaminase as a prototype, we compared the impacts of a substrate analog (1-deaza-adenosine) and a very tight-binding inhibitor/transition state analog (pentostatin) at single and multiple temperatures. At a single temperature, we observed different hydrogen deuterium exchange-mass spectrometry properties for the two ligands, as expected from their 106-fold differences in strength of binding. By contrast, analogous patterns for temperature-dependent hydrogen deuterium exchange mass spectrometry emerge in the presence of both 1-deaza-adenosine and pentostatin, indicating similar impacts of either ligand on the enthalpic barriers for local protein unfolding. We extended temperature-dependent hydrogen deuterium exchange to a function-altering mutant of adenosine deaminase in the presence of pentostatin and revealed a protein thermal network that is highly similar to that previously reported for the apo-enzyme (Gao et al., 2020, JACS 142, 19936-19949). Finally, we discuss the differential impacts of pentostatin binding on overall protein flexibility versus site-specific thermal transfer pathways in the context of models for substrate-induced changes to a distributed protein conformational landscape that act in synergy with embedded protein thermal networks to achieve efficient catalysis.
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Affiliation(s)
- Shuaihua Gao
- Department of Chemistry, University of California, Berkeley, Berkeley, California, USA; California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, California, USA
| | - Wenju Zhang
- David R. Cheriton School of Computer Science, University of Waterloo, Waterloo, Ontario, Canada
| | - Samuel L Barrow
- Department of Chemistry, University of California, Berkeley, Berkeley, California, USA
| | - Anthony T Iavarone
- Department of Chemistry, University of California, Berkeley, Berkeley, California, USA; California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, California, USA
| | - Judith P Klinman
- Department of Chemistry, University of California, Berkeley, Berkeley, California, USA; California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, California, USA; Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California, USA.
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11
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Neitz H, Paul NB, Häge FR, Lindner C, Graebner R, Kovermann M, Thomas F. Identification of novel functional mini-receptors by combinatorial screening of split-WW domains. Chem Sci 2022; 13:9079-9090. [PMID: 36091217 PMCID: PMC9365081 DOI: 10.1039/d2sc01078j] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 07/14/2022] [Indexed: 11/21/2022] Open
Abstract
β-Sheet motifs such as the WW domain are increasingly being explored as building blocks for synthetic biological applications. Since the sequence-structure relationships of β-sheet motifs are generally complex compared to the well-studied α-helical coiled coil (CC), other approaches such as combinatorial screening should be included to vary the function of the peptide. In this study, we present a combinatorial approach to identify novel functional mini-proteins based on the WW-domain scaffold, which takes advantage of the successful reconstitution of the fragmented WW domain of hPin1 (hPin1WW) by CC association. Fragmentation of hPin1WW was performed in both loop 1 (CC-hPin1WW-L1) and loop 2 (CC-hPin1WW-L2), and the respective fragments were linked to the strands of an antiparallel heterodimeric CC. Structural analysis by CD and NMR spectroscopy revealed structural reconstitution of the WW-domain scaffold only in CC-hPin1WW-L1, but not in CC-hPin1WW-L2. Furthermore, by using 1H-15N HSQC NMR, fluorescence and CD spectroscopy, we demonstrated that binding properties of fragmented hPin1WW in CC-hPin1WW-L1 were fully restored by CC association. To demonstrate the power of this approach as a combinatorial screening platform, we synthesized a four-by-six library of N- and C-terminal hPin1WW-CC peptide fragments that was screened for a WW domain that preferentially binds to ATP over cAMP, phophocholine, or IP6. Using this screening platform, we identified one WW domain, which specifically binds ATP, and a phosphorylcholine-specific WW-based mini-receptor, both having binding dissociation constants in the lower micromolar range.
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Affiliation(s)
- Hermann Neitz
- Institute of Organic Chemistry, University of Würzburg Am Hubland Würzburg 97074 Germany
| | - Niels Benjamin Paul
- Institute of Organic and Biomolecular Chemistry, University of Göttingen Tammannstr. 2 Göttingen 37077 Germany
| | - Florian R Häge
- Institute of Organic Chemistry, Heidelberg University Im Neuenheimer Feld 270 Heidelberg 69120 Germany
- Centre for Advanced Materials, Heidelberg University Im Neuenheimer Feld 225 Heidelberg 69120 Germany
| | - Christina Lindner
- Institute of Organic Chemistry, Heidelberg University Im Neuenheimer Feld 270 Heidelberg 69120 Germany
- Centre for Advanced Materials, Heidelberg University Im Neuenheimer Feld 225 Heidelberg 69120 Germany
| | - Roman Graebner
- Institute of Organic Chemistry, Heidelberg University Im Neuenheimer Feld 270 Heidelberg 69120 Germany
- Centre for Advanced Materials, Heidelberg University Im Neuenheimer Feld 225 Heidelberg 69120 Germany
| | - Michael Kovermann
- Department of Chemistry, University of Konstanz Universitätsstraße 10 Konstanz 78457 Germany
| | - Franziska Thomas
- Institute of Organic Chemistry, Heidelberg University Im Neuenheimer Feld 270 Heidelberg 69120 Germany
- Centre for Advanced Materials, Heidelberg University Im Neuenheimer Feld 225 Heidelberg 69120 Germany
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12
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Gao S, Klinman JP. Functional roles of enzyme dynamics in accelerating active site chemistry: Emerging techniques and changing concepts. Curr Opin Struct Biol 2022; 75:102434. [PMID: 35872562 PMCID: PMC9901422 DOI: 10.1016/j.sbi.2022.102434] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/15/2022] [Accepted: 06/21/2022] [Indexed: 02/08/2023]
Abstract
With the growing acceptance of the contribution of protein conformational ensembles to enzyme catalysis and regulation, research in the field of protein dynamics has shifted toward an understanding of the atomistic properties of protein dynamical networks and the mechanisms and time scales that control such behavior. A full description of an enzymatic reaction coordinate is expected to extend beyond the active site and include site-specific networks that communicate with the protein/water interface. Advances in experimental tools for the spatial resolution of thermal activation pathways are being complemented by biophysical methods for visualizing dynamics in real time. An emerging multidimensional model integrates the impacts of bound substrate/effector on the distribution of protein substates that are in rapid equilibration near room temperature with reaction-specific protein embedded heat transfer conduits.
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Affiliation(s)
- Shuaihua Gao
- Department of Chemistry, University of California, Berkeley, CA, 94720, United States; California Institute for Quantitative Biosciences, University of California, Berkeley, CA, 94720, United States. https://twitter.com/S_H_Gao
| | - Judith P Klinman
- Department of Chemistry, University of California, Berkeley, CA, 94720, United States; California Institute for Quantitative Biosciences, University of California, Berkeley, CA, 94720, United States; Department of Molecular and Cell Biology, University of California, Berkeley, CA, 94720, United States.
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13
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Borsley S, Leigh DA, Roberts BMW. Chemical fuels for molecular machinery. Nat Chem 2022; 14:728-738. [PMID: 35778564 DOI: 10.1038/s41557-022-00970-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 05/10/2022] [Indexed: 12/11/2022]
Abstract
Chemical reaction networks that transform out-of-equilibrium 'fuel' to 'waste' are the engines that power the biomolecular machinery of the cell. Inspired by such systems, autonomous artificial molecular machinery is being developed that functions by catalysing the decomposition of chemical fuels, exploiting kinetic asymmetry to harness energy released from the fuel-to-waste reaction to drive non-equilibrium structures and dynamics. Different aspects of chemical fuels profoundly influence their ability to power molecular machines. Here we consider the structure and properties of the fuels that biology has evolved and compare their features with those of the rudimentary synthetic chemical fuels that have so far been used to drive autonomous non-equilibrium molecular-level dynamics. We identify desirable, but context-specific, traits for chemical fuels together with challenges and opportunities for the design and invention of new chemical fuels to power synthetic molecular machinery and other dissipative nanoscale processes.
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Affiliation(s)
- Stefan Borsley
- Department of Chemistry, University of Manchester, Manchester, UK
| | - David A Leigh
- Department of Chemistry, University of Manchester, Manchester, UK.
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14
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Karamitros CS, Murray K, Winemiller B, Lamb C, Stone EM, D'Arcy S, Johnson KA, Georgiou G. Leveraging intrinsic flexibility to engineer enhanced enzyme catalytic activity. Proc Natl Acad Sci U S A 2022; 119:e2118979119. [PMID: 35658075 PMCID: PMC9191678 DOI: 10.1073/pnas.2118979119] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 03/01/2022] [Indexed: 11/18/2022] Open
Abstract
Dynamic motions of enzymes occurring on a broad range of timescales play a pivotal role in all steps of the reaction pathway, including substrate binding, catalysis, and product release. However, it is unknown whether structural information related to conformational flexibility can be exploited for the directed evolution of enzymes with higher catalytic activity. Here, we show that mutagenesis of residues exclusively located at flexible regions distal to the active site of Homo sapiens kynureninase (HsKYNase) resulted in the isolation of a variant (BF-HsKYNase) in which the rate of the chemical step toward kynurenine was increased by 45-fold. Mechanistic pre–steady-state kinetic analysis of the wild type and the evolved enzyme shed light on the underlying effects of distal mutations (>10 Å from the active site) on the rate-limiting step of the catalytic cycle. Hydrogen-deuterium exchange coupled to mass spectrometry and molecular dynamics simulations revealed that the amino acid substitutions in BF-HsKYNase allosterically affect the flexibility of the pyridoxal-5′-phosphate (PLP) binding pocket, thereby impacting the rate of chemistry, presumably by altering the conformational ensemble and sampling states more favorable to the catalyzed reaction.
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Affiliation(s)
| | - Kyle Murray
- Department of Chemistry and Biochemistry, University of Texas at Dallas, Richardson, TX 75080
| | - Brent Winemiller
- Department of Chemical Engineering, University of Texas at Austin, Austin, TX 78712
| | - Candice Lamb
- Department of Chemical Engineering, University of Texas at Austin, Austin, TX 78712
| | - Everett M. Stone
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712
- Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712
- Department of Oncology, Dell Medical School, University of Texas at Austin, Austin, TX 78712
- LiveSTRONG Cancer Institutes, Dell Medical School, University of Texas at Austin, Austin, TX 78712
| | - Sheena D'Arcy
- Department of Chemistry and Biochemistry, University of Texas at Dallas, Richardson, TX 75080
| | - Kenneth A. Johnson
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712
| | - George Georgiou
- Department of Chemical Engineering, University of Texas at Austin, Austin, TX 78712
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712
- Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712
- Department of Oncology, Dell Medical School, University of Texas at Austin, Austin, TX 78712
- LiveSTRONG Cancer Institutes, Dell Medical School, University of Texas at Austin, Austin, TX 78712
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX 78712
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15
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Borsley S, Kreidt E, Leigh DA, Roberts BMW. Autonomous fuelled directional rotation about a covalent single bond. Nature 2022; 604:80-85. [PMID: 35388198 DOI: 10.1038/s41586-022-04450-5] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/20/2022] [Indexed: 11/09/2022]
Abstract
Biology operates through autonomous chemically fuelled molecular machinery1, including rotary motors such as adenosine triphosphate synthase2 and the bacterial flagellar motor3. Chemists have long sought to create analogous molecular structures with chemically powered, directionally rotating, components4-17. However, synthetic motor molecules capable of autonomous 360° directional rotation about a single bond have proved elusive, with previous designs lacking either autonomous fuelling7,10,12 or directionality6. Here we show that 1-phenylpyrrole 2,2'-dicarboxylic acid18,19 (1a) is a catalysis-driven20,21 motor that can continuously transduce energy from a chemical fuel9,20-27 to induce repetitive 360° directional rotation of the two aromatic rings around the covalent N-C bond that connects them. On treatment of 1a with a carbodiimide21,25-27, intramolecular anhydride formation between the rings and the anhydride's hydrolysis both occur incessantly. Both reactions are kinetically gated28-30 causing directional bias. Accordingly, catalysis of carbodiimide hydration by the motor molecule continuously drives net directional rotation around the N-C bond. The directionality is determined by the handedness of both an additive that accelerates anhydride hydrolysis and that of the fuel, and is easily reversed additive31. More than 97% of fuel molecules are consumed through the chemical engine cycle24 with a directional bias of up to 71:29 with a chirality-matched fuel and additive. In other words, the motor makes a 'mistake' in direction every three to four turns. The 26-atom motor molecule's simplicity augurs well for its structural optimization and the development of derivatives that can be interfaced with other components for the performance of work and tasks32-36.
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Affiliation(s)
- Stefan Borsley
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Elisabeth Kreidt
- Department of Chemistry, University of Manchester, Manchester, UK
| | - David A Leigh
- Department of Chemistry, University of Manchester, Manchester, UK. .,School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China.
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16
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Dong F, Zhang M, Ma R, Lu C, Xu F. Insights of conformational dynamics on catalytic activity in the computational stability design of Bacillus subtilis LipA. Arch Biochem Biophys 2022; 722:109196. [PMID: 35339426 DOI: 10.1016/j.abb.2022.109196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 03/19/2022] [Accepted: 03/21/2022] [Indexed: 11/18/2022]
Abstract
In protein engineering, the contributions of individual mutations to designed combinatorial mutants are unpredictable. Screening designed mutations that affect enzyme catalytic activity enables evolutions towards efficient activities. Here, Bacillus subtilis LipA (BSLA) was selected as a model protein for thermostabilization designs, and the circular dichroism measurements showed six combinatorial designs with improved stability (from 5.81 °C to 13.61 °C). Based on molecular dynamic simulations, the conformational dynamics of the mutants revealed that mutations alter the populations of conformational states and the increased ensembles of inactive conformations might lead to a reduction in activity. We further demonstrated that the mutations responsible for the reduced enzyme catalytic activity involved a short dynamic correlation path to disturbing the equilibrium conformation of active sites. By removing N82V, which had a close dynamic correlation to the active sites in mutant D3, the redesigned mutant RD3 had an increased activity of 57.6%. By combining computational simulation with experimental verification, this work established that essential sites to counteract the activity-stability trade-off in multipoint combinatorial mutants could be computationally predicted and thus provide a possible strategy by which to indirectly or directly guide protein design.
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Affiliation(s)
- Fangying Dong
- Ministry of Education Key Laboratory of Carbohydrate Chemistry and Biotechnology, School of Biotechnology, Jiangnan University, 214122, Wuxi, China
| | - Meng Zhang
- Ministry of Education Key Laboratory of Carbohydrate Chemistry and Biotechnology, School of Biotechnology, Jiangnan University, 214122, Wuxi, China
| | - Rui Ma
- Ministry of Education Key Laboratory of Carbohydrate Chemistry and Biotechnology, School of Biotechnology, Jiangnan University, 214122, Wuxi, China
| | - Cheng Lu
- Ministry of Education Key Laboratory of Carbohydrate Chemistry and Biotechnology, School of Biotechnology, Jiangnan University, 214122, Wuxi, China.
| | - Fei Xu
- Ministry of Education Key Laboratory of Carbohydrate Chemistry and Biotechnology, School of Biotechnology, Jiangnan University, 214122, Wuxi, China.
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17
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Kohne M, Li W, Ionescu A, Zhu C, Warncke K. Resolution and characterization of contributions of select protein and coupled solvent configurational fluctuations to radical rearrangement catalysis in coenzyme B 12-dependent ethanolamine ammonia-lyase. Methods Enzymol 2022; 669:229-259. [PMID: 35644173 PMCID: PMC9270175 DOI: 10.1016/bs.mie.2021.12.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Coenzyme B12 (adenosylcobalamin) -dependent ethanolamine ammonia-lyase (EAL) is the signature enzyme in ethanolamine utilization metabolism associated with microbiome homeostasis and disease conditions in the human gut. The enzyme conducts a complex choreography of bond-making/bond-breaking steps that rearrange substrate to products through a radical mechanism, with themes common to other coenzyme B12-dependent and radical enzymes. The methods presented are targeted to test the hypothesis that particular, select protein and coupled solvent configurational fluctuations contribute to enzyme function. The general approach is to correlate enzyme function with an introduced perturbation that alters the properties (for example, degree of concertedness, or collectiveness) of protein and coupled solvent dynamics. Methods for sample preparation and low-temperature kinetic measurements by using temperature-step reaction initiation and time-resolved, full-spectrum electron paramagnetic resonance spectroscopy are detailed. A framework for interpretation of results obtained in ensemble systems under conditions of statistical equilibrium within the reacting, globally unstable state is presented. The temperature-dependence of the first-order rate constants for decay of the cryotrapped paramagnetic substrate radical state in EAL, through the chemical step of radical rearrangement, displays a piecewise-continuous Arrhenius dependence from 203 to 295K, punctuated by a kinetic bifurcation over 219-220K. The results reveal the obligatory contribution of a class of select collective protein and coupled solvent fluctuations to the interconversion of two resolved, sequential configurational substates, on the decay time scale. The select class of collective fluctuations also contributes to the chemical step. The methods and analysis are generally applicable to other coenzyme B12-dependent and related radical enzymes.
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Affiliation(s)
- Meghan Kohne
- Department of Physics, Emory University, Atlanta, GA, United States
| | - Wei Li
- Department of Physics, Emory University, Atlanta, GA, United States
| | - Alina Ionescu
- Department of Physics, Emory University, Atlanta, GA, United States
| | - Chen Zhu
- Department of Physics, Emory University, Atlanta, GA, United States
| | - Kurt Warncke
- Department of Physics, Emory University, Atlanta, GA, United States.
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18
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Dang M, Lim L, Roy A, Song J. Myricetin Allosterically Inhibits the Dengue NS2B-NS3 Protease by Disrupting the Active and Locking the Inactive Conformations. ACS OMEGA 2022; 7:2798-2808. [PMID: 35097276 PMCID: PMC8793048 DOI: 10.1021/acsomega.1c05569] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 12/31/2021] [Indexed: 05/22/2023]
Abstract
The dengue NS2B-NS3 protease existing in equilibrium between the active and inactive forms is essential for virus replication, thus representing a key drug target. Here, myricetin, a plant flavonoid, was characterized to noncompetitively inhibit the dengue protease. Further NMR study identified the protease residues perturbed by binding to myricetin, which were utilized to construct the myricetin-protease complexes. Strikingly, in the active form, myricetin binds to a new allosteric site (AS2) far away from the active site pocket and the allosteric site (AS1) for binding curcumin, while in the inactive form, it binds to both AS1 and AS2. To decipher the mechanism for the allosteric inhibition by myricetin, we conducted molecular dynamics simulations on different forms of dengue NS2B-NS3 proteases. Unexpectedly, the binding of myricetin to AS2 is sufficient to disrupt the active conformation by displacing the characteristic NS2B C-terminal β-hairpin from the active site pocket. By contrast, the binding of myricetin to AS1 and AS2 results in locking the inactive conformation. Therefore, myricetin represents the first small molecule, which allosterically inhibits the dengue protease by both disrupting the active conformation and locking the inactive conformation. The results enforce the notion that a global allosteric network exists in the dengue NS2B-NS3 protease, which is susceptible to allosteric inhibition by small molecules such as myricetin and curcumin. As myricetin has been extensively used as a food additive, it might be directly utilized to fight the dengue infections and as a promising starting material for further design of potent allosteric inhibitors.
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19
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Marton Menendez A, Nesbitt DJ. Lysine-Dependent Entropy Effects in the B. subtilis Lysine Riboswitch: Insights from Single-Molecule Thermodynamic Studies. J Phys Chem B 2021; 126:69-79. [PMID: 34958583 DOI: 10.1021/acs.jpcb.1c07833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Riboswitches play an important role in RNA-based sensing/gene regulation control for many bacteria. In particular, the accessibility of multiple conformational states at physiological temperatures allows riboswitches to selectively bind a cognate ligand in the aptamer domain, which triggers secondary structural changes in the expression platform, and thereby "switching" between on or off transcriptional or translational states for the downstream RNA. The present work exploits temperature-controlled, single-molecule total internal reflection fluorescence (TIRF) microscopy to study the thermodynamic landscape of such ligand binding/folding processes, specifically for the Bacillus subtilis lysine riboswitch. The results confirm that the riboswitch folds via an induced-fit (IF) mechanism, in which cognate lysine ligand first binds to the riboswitch before structural rearrangement takes place. The transition state to folding is found to be enthalpically favored (ΔHfold‡ < 0), yet with a free-energy barrier that is predominantly entropic (-TΔSfold‡ > 0), which results in folding (unfolding) rate constants strongly dependent (independent) of lysine concentration. Analysis of the single-molecule kinetic "trajectories" reveals this rate constant dependence of kfold on lysine to be predominantly entropic in nature, with the additional lysine conferring preferential advantage to the folding process by the presence of ligands correctly oriented with respect to the riboswitch platform. By way of contrast, van't Hoff analysis reveals enthalpic contributions to the overall folding thermodynamics (ΔH0) to be surprisingly constant and robustly independent of lysine concentration. The results demonstrate the crucial role of hydrogen bonding between the ligand and riboswitch platform but with only a relatively modest fraction (45%) of the overall enthalpy change needed to access the transition state and initiate transcriptional switching.
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Affiliation(s)
- Andrea Marton Menendez
- JILA, University of Colorado Boulder and National Institute of Standards and Technology, Boulder, Colorado 80309, United States.,Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - David J Nesbitt
- JILA, University of Colorado Boulder and National Institute of Standards and Technology, Boulder, Colorado 80309, United States.,Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States.,Department of Physics, University of Colorado Boulder, Boulder, Colorado 80309, United States
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20
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Khairallah A, Ross CJ, Tastan Bishop Ö. GTP Cyclohydrolase I as a Potential Drug Target: New Insights into Its Allosteric Modulation via Normal Mode Analysis. J Chem Inf Model 2021; 61:4701-4719. [PMID: 34450011 DOI: 10.1021/acs.jcim.1c00898] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Guanosine triphosphate (GTP) cyclohydrolase I (GCH1) catalyzes the conversion of GTP into dihydroneopterin triphosphate (DHNP). DHNP is the first intermediate of the folate de novo biosynthesis pathway in prokaryotic and lower eukaryotic microorganisms and the tetrahydrobiopterin (BH4) biosynthesis pathway in higher eukaryotes. The de novo folate biosynthesis provides essential cofactors for DNA replication, cell division, and synthesis of key amino acids in rapidly replicating pathogen cells, such as Plasmodium falciparum (P. falciparum), a causative agent of malaria. In eukaryotes, the product of the BH4 biosynthesis pathway is essential for the production of nitric oxide and several neurotransmitter precursors. An increased copy number of the malaria parasite P. falciparum GCH1 gene has been reported to influence antimalarial antifolate drug resistance evolution, whereas mutations in the human GCH1 are associated with neuropathic and inflammatory pain disorders. Thus, GCH1 stands as an important and attractive drug target for developing therapeutics. The GCH1 intrinsic dynamics that modulate its activity remains unclear, and key sites that exert allosteric effects across the structure are yet to be elucidated. This study employed the anisotropic network model to analyze the intrinsic motions of the GCH1 structure alone and in complex with its regulatory partner protein. We showed that the GCH1 tunnel-gating mechanism is regulated by a global shear motion and an outward expansion of the central five-helix bundle. We further identified hotspot residues within sites of structural significance for the GCH1 intrinsic allosteric modulation. The obtained results can provide a solid starting point to design novel antineuropathic treatments for humans and novel antimalarial drugs against the malaria parasite P. falciparum GCH1 enzyme.
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Affiliation(s)
- Afrah Khairallah
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown 6140, South Africa
| | - Caroline J Ross
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown 6140, South Africa
| | - Özlem Tastan Bishop
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown 6140, South Africa
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21
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Goldstein M, Goodey NM. Distal Regions Regulate Dihydrofolate Reductase-Ligand Interactions. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2021; 2253:185-219. [PMID: 33315225 DOI: 10.1007/978-1-0716-1154-8_12] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Protein motions play a fundamental role in enzyme catalysis and ligand binding. The relationship between protein motion and function has been extensively investigated in the model enzyme dihydrofolate reductase (DHFR). DHFR is an essential enzyme that catalyzes the reduction of dihydrofolate to tetrahydrofolate. Numerous experimental and computational methods have been used to probe the motions of DHFR through the catalytic cycle and to investigate the effect of distal mutations on DHFR motions and ligand binding. These experimental investigations have pushed forward the study of protein motions and their role in protein-ligand interactions. The introduction of mutations distal to the active site has been shown to have profound effects on ligand binding, hydride transfer rates and catalytic efficacy and these changes are captured by enzyme kinetics measurements. Distal mutations have been shown to exert their effects through a network of correlated amino acids and these effects have been investigated by NMR, protein dynamics, and analysis of coupled amino acids. The experimental methods and the findings that are reviewed here have broad implications for our understanding of enzyme mechanisms, ligand binding and for the future design and discovery of enzyme inhibitors.
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Affiliation(s)
- Melanie Goldstein
- Department of Chemistry and Biochemistry, Montclair State University, Montclair, NJ, USA
| | - Nina M Goodey
- Department of Chemistry and Biochemistry, Montclair State University, Montclair, NJ, USA.
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22
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Xu H, Qing X, Wang Q, Li C, Lai L. Dimerization of PHGDH via the catalytic unit is essential for its enzymatic function. J Biol Chem 2021; 296:100572. [PMID: 33753166 PMCID: PMC8081924 DOI: 10.1016/j.jbc.2021.100572] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 03/12/2021] [Accepted: 03/18/2021] [Indexed: 11/25/2022] Open
Abstract
Human D-3-phosphoglycerate dehydrogenase (PHGDH), a key enzyme in de novo serine biosynthesis, is amplified in various cancers and serves as a potential target for anticancer drug development. To facilitate this process, more information is needed on the basic biochemistry of this enzyme. For example, PHGDH was found to form tetramers in solution and the structure of its catalytic unit (sPHGDH) was solved as a dimer. However, how the oligomeric states affect PHGDH enzyme activity remains elusive. We studied the dependence of PHGDH enzymatic activity on its oligomeric states. We found that sPHGDH forms a mixture of monomers and dimers in solution with a dimer dissociation constant of ∼0.58 μM, with the enzyme activity depending on the dimer content. We computationally identified hotspot residues at the sPHGDH dimer interface. Single-point mutants at these sites disrupt dimer formation and abolish enzyme activity. Molecular dynamics simulations showed that dimer formation facilitates substrate binding and maintains the correct conformation required for enzyme catalysis. We further showed that the full-length PHGDH exists as a dynamic mixture of monomers, dimers, and tetramers in solution with enzyme concentration-dependent activity. Mutations that can completely disrupt the sPHGDH dimer show different abilities to interrupt the full-length PHGDH tetramer. Among them, E108A and I121A can also disrupt the oligomeric structures of the full-length PHGDH and abolish its enzyme activity. Our study indicates that disrupting the oligomeric structure of PHGDH serves as a novel strategy for PHGDH drug design and the hotspot residues identified can guide the design process.
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Affiliation(s)
- Hanyu Xu
- BNLMS, Peking-Tsinghua Center for Life Sciences at College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Xiaoyu Qing
- BNLMS, Peking-Tsinghua Center for Life Sciences at College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Qian Wang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, China
| | - Chunmei Li
- Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Luhua Lai
- BNLMS, Peking-Tsinghua Center for Life Sciences at College of Chemistry and Molecular Engineering, Peking University, Beijing, China; Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China.
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23
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Ma B, Bai G, Nussinov R, Ding J, Wang YX. Conformational Ensemble of TteAdoCbl Riboswitch Provides Stable Structural Elements for Conformation Selection and Population Shift in Cobalamin Recognition. J Phys Chem B 2021; 125:2589-2596. [PMID: 33683130 PMCID: PMC9272747 DOI: 10.1021/acs.jpcb.1c00038] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cobalamin riboswitch is a cis-regulatory element widely found in the 5'-UTRs of the vitamin B12-associated genes in bacteria, resulting in modulation and production of a particular protein. Thermoanaerobacter tengcongensis (Tte) AdoCbl riboswitches are the largest of the known riboswitches with 210 nucleotides, partially due to its long peripheral P6-extension, which enable high affinity of AdoCbl. Two structural elements, T-loop/T-looplike motif and kissing loop are key to the global folding of the RNA. While the structure of the TteAdoCbl riboswitch complex is known, we still do not understand the structure and conformation before AdoCbl ligand recognition. In order to delineate the conformational changes and the stabilities of long-range interactions, we have performed extensive all-atom replica-exchange molecular dynamics simulations of the TteAdoCbl riboswitch with a total simulation time of 2296 ns. We found that both the T-loop/T-looplike motif and kissing loop are very stable with ligand binding. The gating conformation changes of P6-extension allow the ligand to bind to the preorganized kissing loop binding pocket. The T-loop/T-looplike motif has much more hydrogen bonds than observed in TteAdoCbl riboswitch complex crystal structure, indicating an allosteric response of the T-loop/T-looplike motif. Our study demonstrated that the conformational ensemble of TteAdoCbl riboswitch provides stable structural elements for conformation selection and population shift in cobalamin recognition.
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Affiliation(s)
- Buyong Ma
- Engineering Research Center of Cell and Therapeutic Antibody, MOE, School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China
- Basic Science Program, Leidos Biomedical Research, Inc. Laboratory of Cancer ImmunoMetabolism, National Cancer Institute, Frederick, Maryland 21702, United States
| | - Ganggang Bai
- Engineering Research Center of Cell and Therapeutic Antibody, MOE, School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ruth Nussinov
- Basic Science Program, Leidos Biomedical Research, Inc. Laboratory of Cancer ImmunoMetabolism, National Cancer Institute, Frederick, Maryland 21702, United States
- Sackler Institute of Molecular Medicine, Department of Human Genetics and Molecular Medicine, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Jienyu Ding
- Protein-Nucleic Acid Interaction Section, Structural Biophysics Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland 21702, United States
| | - Yun-Xing Wang
- Protein-Nucleic Acid Interaction Section, Structural Biophysics Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland 21702, United States
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24
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Rufer AC. Drug discovery for enzymes. Drug Discov Today 2021; 26:875-886. [PMID: 33454380 DOI: 10.1016/j.drudis.2021.01.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 12/21/2020] [Accepted: 01/07/2021] [Indexed: 02/06/2023]
Abstract
Enzymes are essential, physiological catalysts involved in all processes of life, including metabolism, cellular signaling and motility, as well as cell growth and division. They are attractive drug targets because of the presence of defined substrate-binding pockets, which can be exploited as binding sites for pharmaceutical enzyme inhibitors. Understanding the reaction mechanisms of enzymes and the molecular mode of action of enzyme inhibitors is indispensable for the discovery and development of potent, efficacious, and safe novel drugs. The combination of classical concepts of enzymology with new experimental and data analysis methods opens new routes for drug discovery.
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Affiliation(s)
- Arne Christian Rufer
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 065/208A, 4070 Basel, Switzerland.
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25
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Kabra A, Li Y. Conformational Dynamics of Deubiquitinase A and Functional Implications. Biochemistry 2021; 60:201-209. [PMID: 33417762 DOI: 10.1021/acs.biochem.0c00834] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Deubiquitinase A (DUBA) belongs to the ovarian tumor family of deubiquitinating enzymes and was initially identified as a negative regulator of type I interferons, whose overproduction has been linked to autoimmune diseases. The deubiquitinating activity of DUBA is positively regulated by phosphorylation at a single serine residue, S177, which results in minimal structural changes. We have previously shown that phosphorylation induces a two-state conformational equilibrium observed only in the active form of DUBA, highlighting the functional importance of DUBA dynamics. Here, we report the conformational dynamics of DUBA on the microsecond-to-millisecond time scales characterized by nuclear magnetic resonance relaxation dispersion experiments. We found that motions on these time scales are highly synchronized in the phosphorylated and nonphosphorylated DUBA. Despite the overall similarity of these two forms, different dynamic properties were observed in helix α1 and the neighboring regions, including residue S177, which likely contribute to the activation of DUBA by phosphorylation. Moreover, our data suggest that transient unfolding of helix α6 drives the global conformational process and that mutations can be introduced to modulate this process, which provides a basis for future studies to define the exact functional roles of motions in DUBA activation and substrate specificity.
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Affiliation(s)
- Ashish Kabra
- Department of Chemistry, University of Louisville, 2320 South Brook Street, Louisville, Kentucky 40208, United States
| | - Ying Li
- Department of Chemistry, University of Louisville, 2320 South Brook Street, Louisville, Kentucky 40208, United States
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26
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Lim L, Dang M, Roy A, Kang J, Song J. Curcumin Allosterically Inhibits the Dengue NS2B-NS3 Protease by Disrupting Its Active Conformation. ACS OMEGA 2020; 5:25677-25686. [PMID: 33073093 PMCID: PMC7557217 DOI: 10.1021/acsomega.0c00039] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 09/17/2020] [Indexed: 05/19/2023]
Abstract
Flaviviruses including dengue virus and Zika virus encode a unique two-component NS2B-NS3 protease essential for maturation/infectivity, thus representing a key target for designing antiflavivirus drugs. Here, for the first time, by NMR and molecular docking, we reveal that curcumin allosterically inhibits the dengue protease by binding to a cavity with no overlap with the active site. Further molecular dynamics simulations decode that the binding of curcumin leads to unfolding/displacing the characteristic β-hairpin of the C-terminal NS2B and consequently disrupting the closed (active) conformation of the protease. Our study identified a cavity most likely conserved in all flaviviral NS2B-NS3 proteases, which could thus serve as a therapeutic target for the discovery/design of small-molecule allosteric inhibitors. Moreover, as curcumin has been used as a food additive for thousands of years in many counties, it can be directly utilized to fight the flaviviral infections and as a promising starting for further design of potent allosteric inhibitors.
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27
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Ezebuo FC, Uzochukwu IC. Schistosomal Sulfotransferase Interaction with Oxamniquine Involves Hybrid Mechanism of Induced-fit and Conformational Selection. Curr Comput Aided Drug Des 2020; 16:451-459. [DOI: 10.2174/1573409915666190708103132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 03/25/2019] [Accepted: 05/06/2019] [Indexed: 11/22/2022]
Abstract
Background:
Sulfotransferase family comprises key enzymes involved in drug metabolism. Oxamniquine
is a pro-drug converted into its active form by schistosomal sulfotransferase. The conformational
dynamics of side-chain amino acid residues at the binding site of schistosomal sulfotransferase towards
activation of oxamniquine has not received attention.
Objective:
The study investigated the conformational dynamics of binding site residues in free and oxamniquine
bound schistosomal sulfotransferase systems and their contribution to the mechanism of oxamniquine
activation by schistosomal sulfotransferase using molecular dynamics simulations and binding
energy calculations.
Methods:
Schistosomal sulfotransferase was obtained from Protein Data Bank and both the free and oxamniquine
bound forms were subjected to molecular dynamics simulations using GROMACS-4.5.5 after
modeling it’s missing amino acid residues with SWISS-MODEL. Amino acid residues at its binding site
for oxamniquine was determined and used for Principal Component Analysis and calculations of side-chain
dihedrals. In addition, binding energy of the oxamniquine bound system was calculated using g_MMPBSA.
Results:
The results showed that binding site amino acid residues in free and oxamniquine bound sulfotransferase
sampled different conformational space involving several rotameric states. Importantly,
Phe45, Ile145 and Leu241 generated newly induced conformations, whereas Phe41 exhibited shift in equilibrium
of its conformational distribution. In addition, the result showed binding energy of -130.091 ±
8.800 KJ/mol and Phe45 contributed -9.8576 KJ/mol.
Conclusion:
The results showed that schistosomal sulfotransferase binds oxamniquine by relying on hybrid
mechanism of induced fit and conformational selection models. The findings offer new insight into sulfotransferase
engineering and design of new drugs that target sulfotransferase.
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Affiliation(s)
- Fortunatus C. Ezebuo
- Drug Design and Informatics Group, Faculty of Pharmaceutical Sciences, Nnamdi Azikiwe University, PMB 5025 Awka 420281, Anambra State, Nigeria
| | - Ikemefuna C. Uzochukwu
- Drug Design and Informatics Group, Faculty of Pharmaceutical Sciences, Nnamdi Azikiwe University, PMB 5025 Awka 420281, Anambra State, Nigeria
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28
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Hitzenberger M, Götz A, Menig S, Brunschweiger B, Zacharias M, Scharnagl C. The dynamics of γ-secretase and its substrates. Semin Cell Dev Biol 2020; 105:86-101. [DOI: 10.1016/j.semcdb.2020.04.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 04/09/2020] [Accepted: 04/15/2020] [Indexed: 12/18/2022]
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29
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Yang G, Miton CM, Tokuriki N. A mechanistic view of enzyme evolution. Protein Sci 2020; 29:1724-1747. [PMID: 32557882 PMCID: PMC7380680 DOI: 10.1002/pro.3901] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/14/2020] [Accepted: 06/16/2020] [Indexed: 12/15/2022]
Abstract
New enzyme functions often evolve through the recruitment and optimization of latent promiscuous activities. How do mutations alter the molecular architecture of enzymes to enhance their activities? Can we infer general mechanisms that are common to most enzymes, or does each enzyme require a unique optimization process? The ability to predict the location and type of mutations necessary to enhance an enzyme's activity is critical to protein engineering and rational design. In this review, via the detailed examination of recent studies that have shed new light on the molecular changes underlying the optimization of enzyme function, we provide a mechanistic perspective of enzyme evolution. We first present a global survey of the prevalence of activity-enhancing mutations and their distribution within protein structures. We then delve into the molecular solutions that mediate functional optimization, specifically highlighting several common mechanisms that have been observed across multiple examples. As distinct protein sequences encounter different evolutionary bottlenecks, different mechanisms are likely to emerge along evolutionary trajectories toward improved function. Identifying the specific mechanism(s) that need to be improved upon, and tailoring our engineering efforts to each sequence, may considerably improve our chances to succeed in generating highly efficient catalysts in the future.
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Affiliation(s)
- Gloria Yang
- Michael Smith LaboratoriesUniversity of British ColumbiaVancouverBritish ColumbiaCanada
| | - Charlotte M. Miton
- Michael Smith LaboratoriesUniversity of British ColumbiaVancouverBritish ColumbiaCanada
| | - Nobuhiko Tokuriki
- Michael Smith LaboratoriesUniversity of British ColumbiaVancouverBritish ColumbiaCanada
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30
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Kahler U, Kamenik AS, Waibl F, Kraml J, Liedl KR. Protein-Protein Binding as a Two-Step Mechanism: Preselection of Encounter Poses during the Binding of BPTI and Trypsin. Biophys J 2020; 119:652-666. [PMID: 32697976 PMCID: PMC7399559 DOI: 10.1016/j.bpj.2020.06.032] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 06/16/2020] [Accepted: 06/29/2020] [Indexed: 11/04/2022] Open
Abstract
Biomolecular recognition between proteins follows complex mechanisms, the understanding of which can substantially advance drug discovery efforts. Here, we track each step of the binding process in atomistic detail with molecular dynamics simulations using trypsin and its inhibitor bovine pancreatic trypsin inhibitor (BPTI) as a model system. We use umbrella sampling to cover a range of unbinding pathways. Starting from these simulations, we subsequently seed classical simulations at different stages of the process and combine them to a Markov state model. We clearly identify three kinetically separated states (an unbound state, an encounter state, and the final complex) and describe the mechanisms that dominate the binding process. From our model, we propose the following sequence of events. The initial formation of the encounter complex is driven by long-range interactions because opposite charges in trypsin and BPTI draw them together. The encounter complex features the prealigned binding partners with binding sites still partially surrounded by solvation shells. Further approaching leads to desolvation and increases the importance of van der Waals interactions. The native binding pose is adopted by maximizing short-range interactions. Thereby side-chain rearrangements ensure optimal shape complementarity. In particular, BPTI’s P1 residue adapts to the S1 pocket and prime site residues reorient to optimize interactions. After the paradigm of conformation selection, binding-competent conformations of BPTI and trypsin are already present in the apo ensembles and their probabilities increase during this proposed two-step association process. This detailed characterization of the molecular forces driving the binding process includes numerous aspects that have been discussed as central to the binding of trypsin and BPTI and protein complex formation in general. In this study, we combine all these aspects into one comprehensive model of protein recognition. We thereby contribute to enhance our general understanding of this fundamental mechanism, which is particularly critical as the development of biopharmaceuticals continuously gains significance.
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Affiliation(s)
- Ursula Kahler
- Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innsbruck, Austria
| | - Anna S Kamenik
- Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innsbruck, Austria
| | - Franz Waibl
- Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innsbruck, Austria
| | - Johannes Kraml
- Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innsbruck, Austria
| | - Klaus R Liedl
- Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innsbruck, Austria.
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31
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Rosenberg MM, Yao T, Patton GC, Redfield AG, Roberts MF, Hedstrom L. Enzyme-Substrate-Cofactor Dynamical Networks Revealed by High-Resolution Field Cycling Relaxometry. Biochemistry 2020; 59:2359-2370. [PMID: 32479091 PMCID: PMC8364753 DOI: 10.1021/acs.biochem.0c00212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The remarkable power and specificity of enzyme catalysis rely on the dynamic alignment of the enzyme, substrates, and cofactors, yet the role of dynamics has usually been approached from the perspective of the protein. We have been using an underappreciated NMR technique, subtesla high-resolution field cycling 31P NMR relaxometry, to investigate the dynamics of the enzyme-bound substrates and cofactor on guanosine-5'-monophosphate reductase (GMPR). GMPR forms two dead end, yet catalytically competent, complexes that mimic distinct steps in the catalytic cycle: E·IMP·NADP+ undergoes a partial hydride transfer reaction, while E·GMP·NADP+ undergoes a partial deamination reaction. A different cofactor conformation is required for each partial reaction. Here we report the effects of mutations designed to perturb cofactor conformation and ammonia binding with the goal of identifying the structural features that contribute to the distinct dynamic signatures of the hydride transfer and deamination complexes. These experiments suggest that Asp129 is a central cog in a dynamic network required for both hydride transfer and deamination. In contrast, Lys77 modulates the conformation and mobility of substrates and cofactors in a reaction-specific manner. Thr105 and Tyr318 are part of a deamination-specific dynamic network that includes the 2'-OH of GMP. These residues have comparatively little effect on the dynamic properties of the hydride transfer complex. These results further illustrate the potential of high-resolution field cycling NMR relaxometry for the investigation of ligand dynamics. In addition, exchange experiments indicate that NH3/NH4+ has a high affinity for the deamination complex but a low affinity for the hydride transfer complex, suggesting that the movement of ammonia may gate the cofactor conformational change. Collectively, these experiments reinforce the view that the enzyme, substrates, and cofactor are linked in intricate, reaction-specific, dynamic networks and demonstrate that distal portions of the substrates and cofactors are critical features in these networks.
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Affiliation(s)
- Masha M. Rosenberg
- Department of Biology, Brandeis University, MS009, 415 South St., Waltham MA 02453-9110 USA
| | - Tianjiong Yao
- Department of Biology, Brandeis University, MS009, 415 South St., Waltham MA 02453-9110 USA
| | - Gregory C. Patton
- Department of Biology, Brandeis University, MS009, 415 South St., Waltham MA 02453-9110 USA
| | - Alfred G. Redfield
- Department of Biochemistry, Brandeis University, MS009, 415 South Street, Waltham, MA 02453-9110 USA
| | - Mary F. Roberts
- Department of Chemistry, Boston College, 140 Commonwealth Avenue, Chestnut Hill, MA 02467-9110 USA
| | - Lizbeth Hedstrom
- Department of Biology, Brandeis University, MS009, 415 South St., Waltham MA 02453-9110 USA
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453-3808 USA
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32
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Abstract
The disaccharide trehalose is accumulated in the cytoplasm of some organisms in response to harsh environmental conditions. Trehalose biosynthesis and accumulation are important for the survival of such organisms by protecting the structure and function of proteins and membranes. Trehalose affects the dynamics of proteins and water molecules in the bulk and the protein hydration shell. Enzyme catalysis and other processes dependent on protein dynamics are affected by the viscosity generated by trehalose, as described by the Kramers’ theory of rate reactions. Enzyme/protein stabilization by trehalose against thermal inactivation/unfolding is also explained by the viscosity mediated hindering of the thermally generated structural dynamics, as described by Kramers’ theory. The analysis of the relationship of viscosity–protein dynamics, and its effects on enzyme/protein function and other processes (thermal inactivation and unfolding/folding), is the focus of the present work regarding the disaccharide trehalose as the viscosity generating solute. Finally, trehalose is widely used (alone or in combination with other compounds) in the stabilization of enzymes in the laboratory and in biotechnological applications; hence, considering the effect of viscosity on catalysis and stability of enzymes may help to improve the results of trehalose in its diverse uses/applications.
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33
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Kadirvel P, Subramanian A, Sridharan N, Subramanian S, Vimaladhasan S, Anishetty S. Molecular dynamics simulation study of Plasmodium falciparum and Escherichia coli SufA: Exploration of conformational changes possibly involved in iron-sulfur cluster transfer. J Biomol Struct Dyn 2020; 39:3300-3311. [PMID: 32364014 DOI: 10.1080/07391102.2020.1764389] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Iron-sulfur (Fe-S) clusters are one of the earliest known metal complexes in biological molecules. Suf system is one of the Fe-S biogenesis pathways. SufA belongs to the Suf pathway. It is an A-type carrier protein that transfers Fe-S clusters from the scaffold to target proteins. Structural studies were performed for the Suf pathway protein, SufA, in order to explore the conformational changes that probably aid in the transfer of Fe-S clusters to target proteins. Three-dimensional (3D) structure of Plasmodium falciparum (Pf) SufA homodimer was obtained by homology modeling using 3D structure of Escherichia coli (Ec) SufA as template. Molecular dynamics (MD) simulation of Pf SufA and Ec SufA homodimers followed by trajectory and pocket analyses were carried out. A co-ordinated displacement of the homodimeric chains in the interfacial region, resembling a swinging trapeze-like movement was observed. Potential involvement of this swinging trapeze-like movement of the residues belonging to the interfacial region has been proposed as a probable mechanism that assists in the transfer of Fe-S cluster from SufA to apo proteins. This was substantiated by protein-protein interaction studies in Pf SufA by performing molecular docking of 3D conformations of Pf SufA obtained from MD trajectory at every 1 ns interval with Pf ferredoxin.Communicated by Ramaswamy H. Sarma.
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34
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Shinobu A, Kobayashi C, Matsunaga Y, Sugita Y. Building a macro-mixing dual-basin Gō model using the Multistate Bennett Acceptance Ratio. Biophys Physicobiol 2019; 16:310-321. [PMID: 31984186 PMCID: PMC6975896 DOI: 10.2142/biophysico.16.0_310] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 08/02/2019] [Indexed: 12/01/2022] Open
Abstract
The dual-basin Gō-model is a structural-based coarsegrained model for simulating a conformational transition between two known structures of a protein. Two parameters are required to produce a dual-basin potential mixed using two single-basin potentials, although the determination of mixing parameters is usually not straightforward. Here, we have developed an efficient scheme to determine the mixing parameters using the Multistate Bennett Acceptance Ratio (MBAR) method after short simulations with a set of parameters. In the scheme, MBAR allows us to predict observables at various unsimulated conditions, which are useful to improve the mixing parameters in the next round of iterative simulations. The number of iterations that are necessary for obtaining the converged mixing parameters are significantly reduced in the scheme. We applied the scheme to two proteins, the glutamine binding protein and the ribose binding protein, for showing the effectiveness in the parameter determination. After obtaining the converged parameters, both proteins show frequent conformational transitions between open and closed states, providing the theoretical basis to investigate structure-dynamics-function relationships of the proteins.
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Affiliation(s)
- Ai Shinobu
- Computational Biophysics Research Team, RIKEN Center for Computational Science, Kobe, Hyogo 650-0047, Japan
| | - Chigusa Kobayashi
- Computational Biophysics Research Team, RIKEN Center for Computational Science, Kobe, Hyogo 650-0047, Japan
| | - Yasuhiro Matsunaga
- Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan
| | - Yuji Sugita
- Computational Biophysics Research Team, RIKEN Center for Computational Science, Kobe, Hyogo 650-0047, Japan
- Theoretical Molecular Science Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
- Laboratory for Biomolecular Function Simulation, RIKEN Center for Biosystems Dynamics Research, Kobe, Hyogo 650-0047, Japan
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35
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Mobaraki N, Hemmateenejad B, Weikl TR, Sakhteman A. On the relationship between docking scores and protein conformational changes in HIV-1 protease. J Mol Graph Model 2019; 91:186-193. [DOI: 10.1016/j.jmgm.2019.06.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 06/10/2019] [Accepted: 06/14/2019] [Indexed: 11/25/2022]
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36
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Bennet IA, Finger LD, Baxter NJ, Ambrose B, Hounslow AM, Thompson MJ, Exell JC, Shahari NNBM, Craggs TD, Waltho JP, Grasby JA. Regional conformational flexibility couples substrate specificity and scissile phosphate diester selectivity in human flap endonuclease 1. Nucleic Acids Res 2019; 46:5618-5633. [PMID: 29718417 PMCID: PMC6009646 DOI: 10.1093/nar/gky293] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 04/09/2018] [Indexed: 02/07/2023] Open
Abstract
Human flap endonuclease-1 (hFEN1) catalyzes the divalent metal ion-dependent removal of single-stranded DNA protrusions known as flaps during DNA replication and repair. Substrate selectivity involves passage of the 5'-terminus/flap through the arch and recognition of a single nucleotide 3'-flap by the α2-α3 loop. Using NMR spectroscopy, we show that the solution conformation of free and DNA-bound hFEN1 are consistent with crystal structures; however, parts of the arch region and α2-α3 loop are disordered without substrate. Disorder within the arch explains how 5'-flaps can pass under it. NMR and single-molecule FRET data show a shift in the conformational ensemble in the arch and loop region upon addition of DNA. Furthermore, the addition of divalent metal ions to the active site of the hFEN1-DNA substrate complex demonstrates that active site changes are propagated via DNA-mediated allostery to regions key to substrate differentiation. The hFEN1-DNA complex also shows evidence of millisecond timescale motions in the arch region that may be required for DNA to enter the active site. Thus, hFEN1 regional conformational flexibility spanning a range of dynamic timescales is crucial to reach the catalytically relevant ensemble.
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Affiliation(s)
- Ian A Bennet
- Centre for Chemical Biology, Department of Chemistry, Krebs Institute for Biomolecular Research, The University of Sheffield, Sheffield S3 7HF, UK
| | - L David Finger
- Centre for Chemical Biology, Department of Chemistry, Krebs Institute for Biomolecular Research, The University of Sheffield, Sheffield S3 7HF, UK
| | - Nicola J Baxter
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Sheffield S10 2TN, UK.,Manchester Institute of Biotechnology, School of Chemistry, The University of Manchester, Manchester M1 7DN, UK
| | - Benjamin Ambrose
- Centre for Chemical Biology, Department of Chemistry, Krebs Institute for Biomolecular Research, The University of Sheffield, Sheffield S3 7HF, UK
| | - Andrea M Hounslow
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Sheffield S10 2TN, UK
| | - Mark J Thompson
- Centre for Chemical Biology, Department of Chemistry, Krebs Institute for Biomolecular Research, The University of Sheffield, Sheffield S3 7HF, UK
| | - Jack C Exell
- Centre for Chemical Biology, Department of Chemistry, Krebs Institute for Biomolecular Research, The University of Sheffield, Sheffield S3 7HF, UK
| | - Nur Nazihah B Md Shahari
- Centre for Chemical Biology, Department of Chemistry, Krebs Institute for Biomolecular Research, The University of Sheffield, Sheffield S3 7HF, UK
| | - Timothy D Craggs
- Centre for Chemical Biology, Department of Chemistry, Krebs Institute for Biomolecular Research, The University of Sheffield, Sheffield S3 7HF, UK
| | - Jonathan P Waltho
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Sheffield S10 2TN, UK.,Manchester Institute of Biotechnology, School of Chemistry, The University of Manchester, Manchester M1 7DN, UK
| | - Jane A Grasby
- Centre for Chemical Biology, Department of Chemistry, Krebs Institute for Biomolecular Research, The University of Sheffield, Sheffield S3 7HF, UK
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37
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Menger FM, Nome F. Interaction vs Preorganization in Enzyme Catalysis. A Dispute That Calls for Resolution. ACS Chem Biol 2019; 14:1386-1392. [PMID: 31150194 DOI: 10.1021/acschembio.8b01029] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
This essay focuses on the debate between Warshel et al. (proponents of preorganization) and Menger and Nome (proponents of spatiotemporal effects) over the source of fast enzyme catalysis. The Warshel model proposes that the main function of enzymes is to push the solvent coordinate toward the transition state. Other physical-organic factors (e.g., desolvation, entropic effects, ground state destabilization, etc.) do not, ostensibly, contribute substantially to the rate. Indeed, physical organic chemistry in its entirety was claimed to be "irrelevant to an enzyme's active site". Preorganization had been applied by Warshel to his "flagship" enzyme, ketosteroid isomerase, but we discuss troubling issues with their ensuing analysis. For example, the concepts of "general acid" and "general base", known to play a role in this enzyme's mechanism, are ignored in the text. In contrast, the spatiotemporal theory postulates that enzyme-like rates (i.e., accelerations >108) occur when two functionalities are held rigidly at contact distances less than ca. 3 Å. Numerous diverse organic systems are shown to bear this out experimentally. Many of these are intramolecular systems where distances between functionalities are known. Among them are fast intramolecular systems where strain is actually generated during the reaction, thereby excluding steric compression as a source of the observed enzyme-like rates. Finally, the account ends with structural data from four active sites of enzymes, obtained by others, all showing contact distances between substrate analogues and enzyme. To our knowledge, contact distances less than the diameter of water are found universally among enzymes, and it is to this fact that we attribute their extremely fast rates given the assumption that enzymes, whatever their particular mechanism, obey elementary chemical principles.
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Affiliation(s)
- Fredric M. Menger
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | - Faruk Nome
- Departamento de Química, Universidade Federal de Santa Catarina, Florianópolis, SC 88040-900 Brazil
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38
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Gruber DR, Toner JJ, Miears HL, Shernyukov AV, Kiryutin AS, Lomzov AA, Endutkin AV, Grin IR, Petrova DV, Kupryushkin MS, Yurkovskaya AV, Johnson EC, Okon M, Bagryanskaya EG, Zharkov DO, Smirnov SL. Oxidative damage to epigenetically methylated sites affects DNA stability, dynamics and enzymatic demethylation. Nucleic Acids Res 2019; 46:10827-10839. [PMID: 30289469 PMCID: PMC6237784 DOI: 10.1093/nar/gky893] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 09/20/2018] [Indexed: 01/20/2023] Open
Abstract
DNA damage can affect various regulatory elements of the genome, with the consequences for DNA structure, dynamics, and interaction with proteins remaining largely unexplored. We used solution NMR spectroscopy, restrained and free molecular dynamics to obtain the structures and investigate dominant motions for a set of DNA duplexes containing CpG sites permuted with combinations of 5-methylcytosine (mC), the primary epigenetic base, and 8-oxoguanine (oxoG), an abundant DNA lesion. Guanine oxidation significantly changed the motion in both hemimethylated and fully methylated DNA, increased base pair breathing, induced BI→BII transition in the backbone 3′ to the oxoG and reduced the variability of shift and tilt helical parameters. UV melting experiments corroborated the NMR and molecular dynamics results, showing significant destabilization of all methylated contexts by oxoG. Notably, some dynamic and thermodynamic effects were not additive in the fully methylated oxidized CpG, indicating that the introduced modifications interact with each other. Finally, we show that the presence of oxoG biases the recognition of methylated CpG dinucleotides by ROS1, a plant enzyme involved in epigenetic DNA demethylation, in favor of the oxidized DNA strand. Thus, the conformational and dynamic effects of spurious DNA oxidation in the regulatory CpG dinucleotide can have far-reaching biological consequences.
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Affiliation(s)
- David R Gruber
- Chemistry Department, Western Washington University, 516 High St., Bellingham, WA 98225-9150, USA
| | - Joanna J Toner
- Chemistry Department, Western Washington University, 516 High St., Bellingham, WA 98225-9150, USA
| | - Heather L Miears
- Chemistry Department, Western Washington University, 516 High St., Bellingham, WA 98225-9150, USA
| | - Andrey V Shernyukov
- N. N. Vorozhtsov Novosibirsk Institute of Organic Chemistry SB RAS, 9 Lavrentieva Ave., Novosibirsk 630090, Russia.,Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia
| | - Alexey S Kiryutin
- Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia.,SB RAS International Tomography Center, 3a Institutskaya St., Novosibirsk 630090, Russia
| | - Alexander A Lomzov
- Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia.,SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., Novosibirsk 630090, Russia
| | - Anton V Endutkin
- Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia.,SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., Novosibirsk 630090, Russia
| | - Inga R Grin
- Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia.,SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., Novosibirsk 630090, Russia
| | - Darya V Petrova
- Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia.,SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., Novosibirsk 630090, Russia
| | - Maxim S Kupryushkin
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., Novosibirsk 630090, Russia
| | - Alexandra V Yurkovskaya
- Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia.,SB RAS International Tomography Center, 3a Institutskaya St., Novosibirsk 630090, Russia
| | | | - Mark Okon
- Department of Biochemistry and Molecular Biology, Department of Chemistry, and Michael Smith Laboratories, University of British Columbia, Vancouver BC, V6T 1Z3, Canada
| | - Elena G Bagryanskaya
- N. N. Vorozhtsov Novosibirsk Institute of Organic Chemistry SB RAS, 9 Lavrentieva Ave., Novosibirsk 630090, Russia.,Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia
| | - Dmitry O Zharkov
- Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia.,SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., Novosibirsk 630090, Russia
| | - Serge L Smirnov
- Chemistry Department, Western Washington University, 516 High St., Bellingham, WA 98225-9150, USA
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39
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Subramanian A, Kadirvel P, Anishetty S. Insights into the pH-dependent catalytic mechanism of Sulfolobus solfataricus β-glycosidase: A molecular dynamics study. Carbohydr Res 2019; 480:42-53. [DOI: 10.1016/j.carres.2019.05.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 05/23/2019] [Accepted: 05/25/2019] [Indexed: 11/27/2022]
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40
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Götz A, Mylonas N, Högel P, Silber M, Heinel H, Menig S, Vogel A, Feyrer H, Huster D, Luy B, Langosch D, Scharnagl C, Muhle-Goll C, Kamp F, Steiner H. Modulating Hinge Flexibility in the APP Transmembrane Domain Alters γ-Secretase Cleavage. Biophys J 2019; 116:2103-2120. [PMID: 31130234 PMCID: PMC6554489 DOI: 10.1016/j.bpj.2019.04.030] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 02/14/2019] [Accepted: 04/15/2019] [Indexed: 01/27/2023] Open
Abstract
Intramembrane cleavage of the β-amyloid precursor protein C99 substrate by γ-secretase is implicated in Alzheimer's disease pathogenesis. Biophysical data have suggested that the N-terminal part of the C99 transmembrane domain (TMD) is separated from the C-terminal cleavage domain by a di-glycine hinge. Because the flexibility of this hinge might be critical for γ-secretase cleavage, we mutated one of the glycine residues, G38, to a helix-stabilizing leucine and to a helix-distorting proline. Both mutants impaired γ-secretase cleavage and also altered its cleavage specificity. Circular dichroism, NMR, and backbone amide hydrogen/deuterium exchange measurements as well as molecular dynamics simulations showed that the mutations distinctly altered the intrinsic structural and dynamical properties of the substrate TMD. Although helix destabilization and/or unfolding was not observed at the initial ε-cleavage sites of C99, subtle changes in hinge flexibility were identified that substantially affected helix bending and twisting motions in the entire TMD. These resulted in altered orientation of the distal cleavage domain relative to the N-terminal TMD part. Our data suggest that both enhancing and reducing local helix flexibility of the di-glycine hinge may decrease the occurrence of enzyme-substrate complex conformations required for normal catalysis and that hinge mobility can thus be conducive for productive substrate-enzyme interactions.
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Affiliation(s)
- Alexander Götz
- Physics of Synthetic Biological Systems (E14), Technical University of Munich, Freising, Germany
| | - Nadine Mylonas
- Biomedical Center (BMC), Metabolic Biochemistry, Ludwig-Maximilians-University, Munich, Germany; German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
| | - Philipp Högel
- Center for Integrated Protein Science Munich at the Lehrstuhl Chemie der Biopolymere, Technical University Munich, Freising, Germany
| | - Mara Silber
- Institute of Organic Chemistry and Institute for Biological Interfaces 4, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Hannes Heinel
- Institute for Medical Physics and Biophysics, Leipzig University, Leipzig, Germany
| | - Simon Menig
- Physics of Synthetic Biological Systems (E14), Technical University of Munich, Freising, Germany
| | - Alexander Vogel
- Institute for Medical Physics and Biophysics, Leipzig University, Leipzig, Germany
| | - Hannes Feyrer
- Institute of Organic Chemistry and Institute for Biological Interfaces 4, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Daniel Huster
- Institute for Medical Physics and Biophysics, Leipzig University, Leipzig, Germany
| | - Burkhard Luy
- Institute of Organic Chemistry and Institute for Biological Interfaces 4, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Dieter Langosch
- Center for Integrated Protein Science Munich at the Lehrstuhl Chemie der Biopolymere, Technical University Munich, Freising, Germany
| | - Christina Scharnagl
- Physics of Synthetic Biological Systems (E14), Technical University of Munich, Freising, Germany.
| | - Claudia Muhle-Goll
- Institute of Organic Chemistry and Institute for Biological Interfaces 4, Karlsruhe Institute of Technology, Karlsruhe, Germany.
| | - Frits Kamp
- Biomedical Center (BMC), Metabolic Biochemistry, Ludwig-Maximilians-University, Munich, Germany
| | - Harald Steiner
- Biomedical Center (BMC), Metabolic Biochemistry, Ludwig-Maximilians-University, Munich, Germany; German Center for Neurodegenerative Diseases (DZNE), Munich, Germany.
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Discovery of processive catalysis by an exo-hydrolase with a pocket-shaped active site. Nat Commun 2019; 10:2222. [PMID: 31110237 PMCID: PMC6527550 DOI: 10.1038/s41467-019-09691-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 03/22/2019] [Indexed: 11/08/2022] Open
Abstract
Substrates associate and products dissociate from enzyme catalytic sites rapidly, which hampers investigations of their trajectories. The high-resolution structure of the native Hordeum exo-hydrolase HvExoI isolated from seedlings reveals that non-covalently trapped glucose forms a stable enzyme-product complex. Here, we report that the alkyl β-d-glucoside and methyl 6-thio-β-gentiobioside substrate analogues perfused in crystalline HvExoI bind across the catalytic site after they displace glucose, while methyl 2-thio-β-sophoroside attaches nearby. Structural analyses and multi-scale molecular modelling of nanoscale reactant movements in HvExoI reveal that upon productive binding of incoming substrates, the glucose product modifies its binding patterns and evokes the formation of a transient lateral cavity, which serves as a conduit for glucose departure to allow for the next catalytic round. This path enables substrate-product assisted processive catalysis through multiple hydrolytic events without HvExoI losing contact with oligo- or polymeric substrates. We anticipate that such enzyme plasticity could be prevalent among exo-hydrolases. Enzyme substrates and products often diffuse too rapidly to assess the catalytic implications of these movements. Here, the authors characterise the structural basis of product and substrate diffusion for an exo-hydrolase and discover a substrate-product assisted processive catalytic mechanism.
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42
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Luo H, Hu L, Ma B, Zhao M, Luo M, Deng Q, Deng S, Ye H, Lin T, Chen J, Wang T, Zhu J, Lu H. Molecular dynamics based improvement of the solubilizing self-cleavable tag Z basic-ΔI-CM application in the preparation of recombinant proteins in Escherichia coli. Biochem Biophys Res Commun 2019; 513:412-418. [PMID: 30967267 DOI: 10.1016/j.bbrc.2019.03.205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 03/29/2019] [Indexed: 10/27/2022]
Abstract
Zbasic-ΔI-CM is a novel intein-based self-cleavable tag we developed to accelerate the soluble expression of recombinant proteins in Escherichia coli (E. coli). Previously we found that intein activity could be interfered by its flanking exteins, and thus reducing the production efficiency and final yield. In this work, we used CXC-chemokine 9 (CXCL9) as a model C-extein, which fusion with Zbasic-ΔI-CM showed high intein activity. When the fusion protein got soluble expression, CXCL9 was released immediately and purified directly from cell lysis supernatant. The results demonstrated that Zbasic-ΔI-CM tag had successfully mediated the efficient production of high-quality CXCL9 with reduced time and resources consumption in comparison with inclusion bodies expression. Molecular dynamics simulations suggested that the improved cleavage activity of Zbasic-ΔI-CM upon fusion with CXCL9 may be due to the higher dynamics of the first half loop and stabilization of the second half loop of intein. Our results proved that the self-cleavable Zbasic-ΔI-CM mediated soluble expression could be a feasible process for cytokines like CXCL9, thus of attractive potentials for production of therapeutic proteins using E. coli expression system.
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Affiliation(s)
- Han Luo
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Lifu Hu
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Buyong Ma
- Basic Science Program, Leidos Biomedical Research, Inc. Cancer and Inflammation Program, National Cancer Research Institute at Frederick, Frederick, MD, 21702, USA
| | - Meiqi Zhao
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Manyu Luo
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Qing Deng
- Regeneromics Laboratory, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Shaorong Deng
- Regeneromics Laboratory, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Hao Ye
- Regeneromics Laboratory, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Tong Lin
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Junsheng Chen
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Tao Wang
- Jecho Biopharmaceuticals Co. Ltd., 2633 Zhongbin Road, Sino-Singapore Tianjin Eco-City, Tianjin, 300467, China
| | - Jianwei Zhu
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China; Jecho Biopharmaceuticals Co. Ltd., 2633 Zhongbin Road, Sino-Singapore Tianjin Eco-City, Tianjin, 300467, China; Jecho Laboratories, Inc., 7320 Executive Way, Frederick, MD, 21704, USA.
| | - Huili Lu
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China.
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Götz A, Högel P, Silber M, Chaitoglou I, Luy B, Muhle-Goll C, Scharnagl C, Langosch D. Increased H-Bond Stability Relates to Altered ε-Cleavage Efficiency and Aβ Levels in the I45T Familial Alzheimer's Disease Mutant of APP. Sci Rep 2019; 9:5321. [PMID: 30926830 PMCID: PMC6440955 DOI: 10.1038/s41598-019-41766-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 02/27/2019] [Indexed: 12/15/2022] Open
Abstract
Cleavage of the amyloid precursor protein's (APP) transmembrane domain (TMD) by γ-secretase is a crucial step in the aetiology of Alzheimer's Disease (AD). Mutations in the APP TMD alter cleavage and lead to familial forms of AD (FAD). The majority of FAD mutations shift the preference of initial cleavage from ε49 to ε48, thus raising the AD-related Aβ42/Aβ40 ratio. The I45T mutation is among the few FAD mutations that do not alter ε-site preference, while it dramatically reduces the efficiency of ε-cleavage. Here, we investigate the impact of the I45T mutation on the backbone dynamics of the substrate TMD. Amide exchange experiments and molecular dynamics simulations in solvent and a lipid bilayer reveal an increased stability of amide hydrogen bonds at the ζ- and γ-cleavage sites. Stiffening of the H-bond network is caused by an additional H-bond between the T45 side chain and the TMD backbone, which alters dynamics within the cleavage domain. In particular, the increased H-bond stability inhibits an upward movement of the ε-sites in the I45T mutant. Thus, an altered presentation of ε-sites to the active site of γ-secretase as a consequence of restricted local flexibility provides a rationale for reduced ε-cleavage efficiency of the I45T mutant.
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Grants
- Deutsche Forschungsgemeinschaft (German Research Foundation)
- Helmholtz-Gemeinschaft (Helmholtz Association)
- Leibniz Supercomputing Centre: Leibniz-Rechenzentrum der Bayerischen Akademie der Wissenschaften, Boltzmannstra&#x00DF;e 1, 85748 Garching bei M&#x00FC;nchen, Germany, WEB: https://www.lrz.de Gauss Centre for Supercomputing: GCS-Gesch&#x00E4;ftsstelle Bonn, Ahrstrasse 45, 53175 Bonn, Germany, WEB: http://www.gauss-centre.eu
- Center for Integrated Protein Science: Munich Center For Integrated Protein Science (CIPSM), Butenandtstr. 5 - 13, 81377 Munich, Germany, WEB: http://www.cipsm.de/ Leibniz Supercomputing Centre: Leibniz-Rechenzentrum der Bayerischen Akademie der Wissenschaften, Boltzmannstra&#x00DF;e 1, 85748 Garching bei M&#x00FC;nchen, Germany, WEB: https://www.lrz.de
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Affiliation(s)
- Alexander Götz
- Lehrstuhl für Physik synthetischer Biosysteme (E14), Technische Universität München, Maximus-von-Imhof Forum 4, 85354, Freising, Germany
| | - Philipp Högel
- Center for Integrated Protein Science Munich (CIPSM) at the Lehrstuhl für Chemie der Biopolymere, Technische Universität München, Weihenstephaner Berg 3, 85354, Freising, Germany
| | - Mara Silber
- Institute of Organic Chemistry and Institute for Biological Interfaces 4, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Iro Chaitoglou
- Center for Integrated Protein Science Munich (CIPSM) at the Lehrstuhl für Chemie der Biopolymere, Technische Universität München, Weihenstephaner Berg 3, 85354, Freising, Germany
| | - Burkhard Luy
- Institute of Organic Chemistry and Institute for Biological Interfaces 4, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Claudia Muhle-Goll
- Institute of Organic Chemistry and Institute for Biological Interfaces 4, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Christina Scharnagl
- Lehrstuhl für Physik synthetischer Biosysteme (E14), Technische Universität München, Maximus-von-Imhof Forum 4, 85354, Freising, Germany.
| | - Dieter Langosch
- Center for Integrated Protein Science Munich (CIPSM) at the Lehrstuhl für Chemie der Biopolymere, Technische Universität München, Weihenstephaner Berg 3, 85354, Freising, Germany.
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44
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Murillo-López J, Zinovjev K, Pereira H, Caniuguir A, Garratt R, Babul J, Recabarren R, Alzate-Morales J, Caballero J, Tuñón I, Cabrera R. Studying the phosphoryl transfer mechanism of the E. coli phosphofructokinase-2: from X-ray structure to quantum mechanics/molecular mechanics simulations. Chem Sci 2019; 10:2882-2892. [PMID: 30996866 PMCID: PMC6429617 DOI: 10.1039/c9sc00094a] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 01/24/2019] [Indexed: 12/31/2022] Open
Abstract
Phosphofructokinases catalyze the ATP-dependent phosphorylation of fructose-6-phosphate and they are highly regulated.
Phosphofructokinases (Pfks) catalyze the ATP-dependent phosphorylation of fructose-6-phosphate (F6P) and they are regulated in a wide variety of organisms. Although numerous aspects of the kinetics and regulation have been characterized for Pfks, the knowledge about the mechanism of the phosphoryl transfer reaction and the transition state lags behind. In this work, we describe the X-ray crystal structure of the homodimeric Pfk-2 from E. coli, which contains products in one site and reactants in the other, as well as an additional ATP molecule in the inhibitory allosteric site adjacent to the reactants. This complex was previously predicted when studying the kinetic mechanism of ATP inhibition. After removing the allosteric ATP, molecular dynamic (MD) simulations revealed conformational changes related to domain packing, as well as stable interactions of Lys27 and Asp256 with donor (ATP) and acceptor (fructose-6-) groups, and of Asp166 with Mg2+. The phosphoryl transfer reaction mechanism catalyzed by Pfk-2 was investigated through Quantum Mechanics/Molecular Mechanics (QM/MM) simulations using a combination of the string method and a path-collective variable for the exploration of its free energy surface. The calculated activation free energies showed that a dissociative mechanism, occurring with a metaphosphate intermediate formation followed by a proton transfer to Asp256, is more favorable than an associative one. The structural analysis reveals the role of Asp256 acting as a catalytic base and Lys27 stabilizing the transition state of the dissociative mechanism.
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Affiliation(s)
- Juliana Murillo-López
- Centro de Bioinformática y Simulación Molecular (CBSM) , Facultad de Ingeniería , Universidad de Talca , 1 Poniente 1141 , Talca , Chile .
| | - Kirill Zinovjev
- Departament de Química Física , Universitat de València , 46100 Burjassot , Spain .
| | - Humberto Pereira
- Instituto de Física de São Carlos , Universidade de São Paulo , São Paulo , Brazil
| | - Andres Caniuguir
- Departamento de Biología , Facultad de Ciencias , Universidad de Chile , Santiago , Chile .
| | - Richard Garratt
- Instituto de Física de São Carlos , Universidade de São Paulo , São Paulo , Brazil
| | - Jorge Babul
- Departamento de Biología , Facultad de Ciencias , Universidad de Chile , Santiago , Chile .
| | - Rodrigo Recabarren
- Centro de Bioinformática y Simulación Molecular (CBSM) , Facultad de Ingeniería , Universidad de Talca , 1 Poniente 1141 , Talca , Chile .
| | - Jans Alzate-Morales
- Centro de Bioinformática y Simulación Molecular (CBSM) , Facultad de Ingeniería , Universidad de Talca , 1 Poniente 1141 , Talca , Chile .
| | - Julio Caballero
- Centro de Bioinformática y Simulación Molecular (CBSM) , Facultad de Ingeniería , Universidad de Talca , 1 Poniente 1141 , Talca , Chile .
| | - Iñaki Tuñón
- Departament de Química Física , Universitat de València , 46100 Burjassot , Spain .
| | - Ricardo Cabrera
- Departamento de Biología , Facultad de Ciencias , Universidad de Chile , Santiago , Chile .
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45
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Pandya MJ, Schiffers S, Hounslow AM, Baxter NJ, Williamson MP. Why the Energy Landscape of Barnase Is Hierarchical. Front Mol Biosci 2018; 5:115. [PMID: 30619881 PMCID: PMC6306431 DOI: 10.3389/fmolb.2018.00115] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 12/07/2018] [Indexed: 01/29/2023] Open
Abstract
We have used NMR and computational methods to characterize the dynamics of the ribonuclease barnase over a wide range of timescales in free and inhibitor-bound states. Using temperature- and denaturant-dependent measurements of chemical shift, we show that barnase undergoes frequent and highly populated hinge bending. Using relaxation dispersion, we characterize a slower and less populated motion with a rate of 750 ± 200 s−1, involving residues around the lip of the active site, which occurs in both free and bound states and therefore suggests conformational selection. Normal mode calculations characterize correlated hinge bending motions on a very rapid timescale. These three measurements are combined with previous measurements and molecular dynamics calculations on barnase to characterize its dynamic landscape on timescales from picoseconds to milliseconds and length scales from 0.1 to 2.5 nm. We show that barnase has two different large-scale fluctuations: one on a timescale of 10−9−10−6 s that has no free energy barrier and is a hinge bending that is determined by the architecture of the protein; and one on a timescale of milliseconds (i.e., 750 s−1) that has a significant free energy barrier and starts from a partially hinge-bent conformation. These two motions can be described as hierarchical, in that the more highly populated faster motion provides a platform for the slower (less probable) motion. The implications are discussed. The use of temperature and denaturant is suggested as a simple and general way to characterize motions on the intermediate ns-μs timescale.
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Affiliation(s)
- Maya J Pandya
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
| | - Stefanie Schiffers
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
| | - Andrea M Hounslow
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
| | - Nicola J Baxter
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
| | - Mike P Williamson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
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46
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Akula S, Vanamamalai VK, Nair Ru VP, Vudem DR, Kancha RK. Elucidation of conformational diversity of druggable enzymes and classification of chemical modulators based on inhibitor-bound structures. J Biomol Struct Dyn 2018; 37:4563-4568. [PMID: 30488775 DOI: 10.1080/07391102.2018.1553740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Sravani Akula
- Molecular Medicine and Therapeutics Laboratory, CPMB, Osmania University , Hyderabad , India
| | | | - Vishnu Prasad Nair Ru
- Molecular Medicine and Therapeutics Laboratory, CPMB, Osmania University , Hyderabad , India
| | | | - Rama Krishna Kancha
- Molecular Medicine and Therapeutics Laboratory, CPMB, Osmania University , Hyderabad , India
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47
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Structurally- and dynamically-driven allostery of the chymotrypsin-like proteases of SARS, Dengue and Zika viruses. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2018; 143:52-66. [PMID: 30217495 PMCID: PMC7111307 DOI: 10.1016/j.pbiomolbio.2018.08.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 08/09/2018] [Accepted: 08/24/2018] [Indexed: 01/19/2023]
Abstract
Coronavirus 3C-like and Flavivirus NS2B-NS3 proteases utilize the chymotrypsin fold to harbor their catalytic machineries but also contain additional domains/co-factors. Over the past decade, we aimed to decipher how the extra domains/co-factors mediate the catalytic machineries of SARS 3C-like, Dengue and Zika NS2B-NS3 proteases by characterizing their folding, structures, dynamics and inhibition with NMR, X-ray crystallography and MD simulations, and the results revealed: 1) the chymotrypsin fold of the SARS 3C-like protease can independently fold, while, by contrast, those of Dengue and Zika proteases lack the intrinsic capacity to fold without co-factors. 2) Mutations on the extra domain of SARS 3C-like protease can transform the active catalytic machinery into the inactive collapsed state by structurally-driven allostery. 3) Amazingly, even without detectable structural changes, mutations on the extra domain are sufficient to either inactivate or enhance the catalytic machinery of SARS 3C-like protease by dynamically-driven allostery. 4) Global networks of correlated motions have been identified: for SARS 3C-like protease, N214A inactivates the catalytic machinery by decoupling the network, while STI/A and STIF/A enhance by altering the patterns of the network. The global networks of Dengue and Zika proteases are coordinated by their NS2B-cofactors. 5) Natural products were identified to allosterically inhibit Zika and Dengue proteases through binding a pocket on the back of the active site. Therefore, by introducing extra domains/cofactors, nature develops diverse strategies to regulate the catalytic machinery embedded on the chymotrypsin fold through folding, structurally- and dynamically-driven allostery, all of which might be exploited to develop antiviral drugs.
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48
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Evolutionary repurposing of a sulfatase: A new Michaelis complex leads to efficient transition state charge offset. Proc Natl Acad Sci U S A 2018; 115:E7293-E7302. [PMID: 30012610 DOI: 10.1073/pnas.1607817115] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The recruitment and evolutionary optimization of promiscuous enzymes is key to the rapid adaptation of organisms to changing environments. Our understanding of the precise mechanisms underlying enzyme repurposing is, however, limited: What are the active-site features that enable the molecular recognition of multiple substrates with contrasting catalytic requirements? To gain insights into the molecular determinants of adaptation in promiscuous enzymes, we performed the laboratory evolution of an arylsulfatase to improve its initially weak phenylphosphonate hydrolase activity. The evolutionary trajectory led to a 100,000-fold enhancement of phenylphosphonate hydrolysis, while the native sulfate and promiscuous phosphate mono- and diester hydrolyses were only marginally affected (≤50-fold). Structural, kinetic, and in silico characterizations of the evolutionary intermediates revealed that two key mutations, T50A and M72V, locally reshaped the active site, improving access to the catalytic machinery for the phosphonate. Measured transition state (TS) charge changes along the trajectory suggest the creation of a new Michaelis complex (E•S, enzyme-substrate), with enhanced leaving group stabilization in the TS for the promiscuous phosphonate (βleavinggroup from -1.08 to -0.42). Rather than altering the catalytic machinery, evolutionary repurposing was achieved by fine-tuning the molecular recognition of the phosphonate in the Michaelis complex, and by extension, also in the TS. This molecular scenario constitutes a mechanistic alternative to adaptation solely based on enzyme flexibility and conformational selection. Instead, rapid functional transitions between distinct chemical reactions rely on the high reactivity of permissive active-site architectures that allow multiple substrate binding modes.
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49
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Maurer D, Enugala TR, Hamnevik E, Bauer P, Lüking M, Petrović D, Hillier H, Kamerlin SCL, Dobritzsch D, Widersten M. Stereo- and Regioselectivity in Catalyzed Transformation of a 1,2-Disubstituted Vicinal Diol and the Corresponding Diketone by Wild Type and Laboratory Evolved Alcohol Dehydrogenases. ACS Catal 2018. [DOI: 10.1021/acscatal.8b01762] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Dirk Maurer
- Department of Chemistry − BMC, Uppsala University, Box 576, SE-751 23 Uppsala, Sweden
| | - Thilak Reddy Enugala
- Department of Chemistry − BMC, Uppsala University, Box 576, SE-751 23 Uppsala, Sweden
| | - Emil Hamnevik
- Department of Chemistry − BMC, Uppsala University, Box 576, SE-751 23 Uppsala, Sweden
| | - Paul Bauer
- Department of Cell and Molecular Biology, Uppsala University, Box 596, SE-751 24 Uppsala, Sweden
- Biophysics, KTH Royal Institute of Technology, SE-100 44, Stockholm, Sweden
| | - Malin Lüking
- Department of Chemistry − BMC, Uppsala University, Box 576, SE-751 23 Uppsala, Sweden
- Department of Cell and Molecular Biology, Uppsala University, Box 596, SE-751 24 Uppsala, Sweden
| | - Dušan Petrović
- Department of Chemistry − BMC, Uppsala University, Box 576, SE-751 23 Uppsala, Sweden
- Department of Cell and Molecular Biology, Uppsala University, Box 596, SE-751 24 Uppsala, Sweden
| | - Heidi Hillier
- Department of Chemistry − BMC, Uppsala University, Box 576, SE-751 23 Uppsala, Sweden
| | - Shina C. L. Kamerlin
- Department of Chemistry − BMC, Uppsala University, Box 576, SE-751 23 Uppsala, Sweden
- Department of Cell and Molecular Biology, Uppsala University, Box 596, SE-751 24 Uppsala, Sweden
| | - Doreen Dobritzsch
- Department of Chemistry − BMC, Uppsala University, Box 576, SE-751 23 Uppsala, Sweden
| | - Mikael Widersten
- Department of Chemistry − BMC, Uppsala University, Box 576, SE-751 23 Uppsala, Sweden
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50
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Götz A, Scharnagl C. Dissecting conformational changes in APP's transmembrane domain linked to ε-efficiency in familial Alzheimer's disease. PLoS One 2018; 13:e0200077. [PMID: 29966005 PMCID: PMC6028146 DOI: 10.1371/journal.pone.0200077] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 06/19/2018] [Indexed: 02/02/2023] Open
Abstract
The mechanism by which familial Alzheimer's disease (FAD) mutations within the transmembrane domain (TMD) of the Amyloid Precursor Protein (APP) affect ε-endoproteolysis is only poorly understood. Thereby, mutations in the cleavage domain reduce ε-efficiency of γ-secretase cleavage and some even shift entry into production lines. Since cleavage occurs within the TMD, a relationship between processing and TMD structure and dynamics seems obvious. Using molecular dynamic simulations, we dissect the dynamic features of wild-type and seven FAD-mutants into local and global components. Mutations consistently enhance hydrogen-bond fluctuations upstream of the ε-cleavage sites but maintain strong helicity there. Dynamic perturbation-response scanning reveals that FAD-mutants target backbone motions utilized in the bound state. Those motions, obscured by large-scale motions in the pre-bound state, provide (i) a dynamic mechanism underlying the proposed coupling between binding and ε-cleavage, (ii) key sites consistent with experimentally determined docking sites, and (iii) the distinction between mutants and wild-type.
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Affiliation(s)
- Alexander Götz
- Technical University of Munich, Chair of Physics of Synthetic Biological Systems, Freising, Germany
| | - Christina Scharnagl
- Technical University of Munich, Chair of Physics of Synthetic Biological Systems, Freising, Germany
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