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Bittner JP, Smirnova I, Jakobtorweihen S. Investigating Biomolecules in Deep Eutectic Solvents with Molecular Dynamics Simulations: Current State, Challenges and Future Perspectives. Molecules 2024; 29:703. [PMID: 38338447 PMCID: PMC10856712 DOI: 10.3390/molecules29030703] [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: 12/06/2023] [Revised: 01/23/2024] [Accepted: 01/24/2024] [Indexed: 02/12/2024] Open
Abstract
Deep eutectic solvents (DESs) have recently gained increased attention for their potential in biotechnological applications. DESs are binary mixtures often consisting of a hydrogen bond acceptor and a hydrogen bond donor, which allows for tailoring their properties for particular applications. If produced from sustainable resources, they can provide a greener alternative to many traditional organic solvents for usage in various applications (e.g., as reaction environment, crystallization agent, or storage medium). To navigate this large design space, it is crucial to comprehend the behavior of biomolecules (e.g., enzymes, proteins, cofactors, and DNA) in DESs and the impact of their individual components. Molecular dynamics (MD) simulations offer a powerful tool for understanding thermodynamic and transport processes at the atomic level and offer insights into their fundamental phenomena, which may not be accessible through experiments. While the experimental investigation of DESs for various biotechnological applications is well progressed, a thorough investigation of biomolecules in DESs via MD simulations has only gained popularity in recent years. Within this work, we aim to provide an overview of the current state of modeling biomolecules with MD simulations in DESs and discuss future directions with a focus for optimizing the molecular simulations and increasing our fundamental knowledge.
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Affiliation(s)
- Jan Philipp Bittner
- Institute of Thermal Separation Processes, Hamburg University of Technology, Eißendorfer Straße 38, 21073 Hamburg, Germany
| | - Irina Smirnova
- Institute of Thermal Separation Processes, Hamburg University of Technology, Eißendorfer Straße 38, 21073 Hamburg, Germany
| | - Sven Jakobtorweihen
- Institute of Thermal Separation Processes, Hamburg University of Technology, Eißendorfer Straße 38, 21073 Hamburg, Germany
- Institute of Chemical Reaction Engineering, Hamburg University of Technology, Eißendorfer Straße 38, 21073 Hamburg, Germany
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2
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Kehrein J, Sotriffer C. Molecular Dynamics Simulations for Rationalizing Polymer Bioconjugation Strategies: Challenges, Recent Developments, and Future Opportunities. ACS Biomater Sci Eng 2024; 10:51-74. [PMID: 37466304 DOI: 10.1021/acsbiomaterials.3c00636] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
The covalent modification of proteins with polymers is a well-established method for improving the pharmacokinetic properties of therapeutically valuable biologics. The conjugated polymer chains of the resulting hybrid represent highly flexible macromolecular structures. As the dynamics of such systems remain rather elusive for established experimental techniques from the field of protein structure elucidation, molecular dynamics simulations have proven as a valuable tool for studying such conjugates at an atomistic level, thereby complementing experimental studies. With a focus on new developments, this review aims to provide researchers from the polymer bioconjugation field with a concise and up to date overview of such approaches. After introducing basic principles of molecular dynamics simulations, as well as methods for and potential pitfalls in modeling bioconjugates, the review illustrates how these computational techniques have contributed to the understanding of bioconjugates and bioconjugation strategies in the recent past and how they may lead to a more rational design of novel bioconjugates in the future.
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Affiliation(s)
- Josef Kehrein
- Institute of Pharmacy and Food Chemistry, University of Würzburg, Würzburg 97074, Germany
| | - Christoph Sotriffer
- Institute of Pharmacy and Food Chemistry, University of Würzburg, Würzburg 97074, Germany
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3
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Leite JP, Lourenço F, Oliveira R, Sousa SF, Mendes MV, Gales L. Crystal structures of Streptomyces tsukubaensis sigma factor SigG1 and anti-sigma RsfG. J Struct Biol 2023; 215:108038. [PMID: 37858875 DOI: 10.1016/j.jsb.2023.108038] [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: 08/03/2023] [Revised: 09/25/2023] [Accepted: 10/16/2023] [Indexed: 10/21/2023]
Abstract
Transcription of specific genes in bacteria under environmental stress is frequently initiated by extracytoplasmic function (ECF) σ factors. ECFs σ factors harbour two conserved domains, σ2 and σ4, for transcription initiation by recognition of the promoter region and recruitment of RNA polymerase (RNAP). The crystal structure of Streptomyces tsukubaensis SigG1, an ECF56-family σ factor, was determined revealing σ2, σ4 and the additional carboxi-terminal domain SnoaL_2 tightly packed in a compact conformation. The structure of anti-sigma RsfG was also determined by X-ray crystallography and shows a rare β-barrel fold. Analysis of the metal binding motifs inside the protein barrel are consistent with Fe(III) binding, which is in agreement with previous findings that the Streptomyces tsukubaensis ECF56 SigG1-RsfG system is involved in metal-ion homeostasis.
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Affiliation(s)
- José P Leite
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, Porto, Porto 4200-135, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, Porto, Porto 4200-135, Portugal; ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira 228, Porto, Porto 4050-313, Portugal
| | - Frederico Lourenço
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, Porto, Porto 4200-135, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, Porto, Porto 4200-135, Portugal
| | - Rute Oliveira
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, Porto, Porto 4200-135, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, Porto, Porto 4200-135, Portugal; ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira 228, Porto, Porto 4050-313, Portugal
| | - Sérgio F Sousa
- UCIBIO/REQUIMTE, BioSIM, Department of Biomedicine, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, Porto 4200-319, Portugal
| | - Marta V Mendes
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, Porto, Porto 4200-135, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, Porto, Porto 4200-135, Portugal
| | - Luís Gales
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, Porto, Porto 4200-135, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, Porto, Porto 4200-135, Portugal; ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira 228, Porto, Porto 4050-313, Portugal.
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4
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Kümmerer F, Orioli S, Lindorff-Larsen K. Fitting Force Field Parameters to NMR Relaxation Data. J Chem Theory Comput 2023. [PMID: 37276045 DOI: 10.1021/acs.jctc.3c00174] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We present an approach to optimize force field parameters using time-dependent data from NMR relaxation experiments. To do so, we scan parameters in the dihedral angle potential energy terms describing the rotation of the methyl groups in proteins and compare NMR relaxation rates calculated from molecular dynamics simulations with the modified force fields to deuterium relaxation measurements of T4 lysozyme. We find that a small modification of Cγ methyl groups improves the agreement with experiments both for the protein used to optimize the force field and when validating using simulations of CI2 and ubiquitin. We also show that these improvements enable a more effective a posteriori reweighting of the MD trajectories. The resulting force field thus enables more direct comparison between simulations and side-chain NMR relaxation data and makes it possible to construct ensembles that better represent the dynamics of proteins in solution.
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Affiliation(s)
- Felix Kümmerer
- Structural Biology and NMR Laboratory, Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen N, Denmark
| | - Simone Orioli
- Structural Biology and NMR Laboratory, Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen N, Denmark
- Structural Biophysics, Niels Bohr Institute, Faculty of Science, University of Copenhagen, DK-2100 Copenhagen Ø, Denmark
| | - Kresten Lindorff-Larsen
- Structural Biology and NMR Laboratory, Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen N, Denmark
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5
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Mortensen JC, Damjanovic J, Miao J, Hui T, Lin Y. A backbone-dependent rotamer library with high (ϕ, ψ) coverage using metadynamics simulations. Protein Sci 2022; 31:e4491. [PMID: 36327064 PMCID: PMC9679973 DOI: 10.1002/pro.4491] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 10/26/2022] [Accepted: 10/28/2022] [Indexed: 12/06/2023]
Abstract
Backbone-dependent rotamer libraries are commonly used to assign the side chain dihedral angles of amino acids when modeling protein structures. Most rotamer libraries are created by curating protein crystal structure data and using various methods to extrapolate the existing data to cover all possible backbone conformations. However, these rotamer libraries may not be suitable for modeling the structures of cyclic peptides and other constrained peptides because these molecules frequently sample backbone conformations rarely seen in the crystal structures of linear proteins. To provide backbone-dependent side chain information beyond the α-helix, β-sheet, and PPII regions, we used explicit-solvent metadynamics simulations of model dipeptides to create a new rotamer library that has high coverage in the (ϕ, ψ) space. Furthermore, this approach can be applied to build high-coverage rotamer libraries for noncanonical amino acids. The resulting Metadynamics of Dipeptides for Rotamer Distribution (MEDFORD) rotamer library predicts the side chain conformations of high-resolution protein crystal structures with similar accuracy (~80%) to a state-of-the-art rotamer library. Our ability to test the accuracy of MEDFORD at predicting the side chain dihedral angles of amino acids in noncanonical backbone conformation is restricted by the limited structural data available for cyclic peptides. For the cyclic peptide data that are currently available, MEDFORD and the state-of-the-art rotamer library perform comparably. However, the two rotamer libraries indeed make different rotamer predictions in noncanonical (ϕ, ψ) regions. For noncanonical amino acids, the MEDFORD rotamer library predicts the χ1 values with approximately 75% accuracy.
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Affiliation(s)
| | | | - Jiayuan Miao
- Department of ChemistryTufts UniversityMedfordMassachusettsUSA
| | - Tiffani Hui
- Department of ChemistryTufts UniversityMedfordMassachusettsUSA
| | - Yu‐Shan Lin
- Department of ChemistryTufts UniversityMedfordMassachusettsUSA
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6
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Novack D, Qian L, Acker G, Voelz VA, Baxter RHG. Oncogenic Mutations in the DNA-Binding Domain of FOXO1 that Disrupt Folding: Quantitative Insights from Experiments and Molecular Simulations. Biochemistry 2022; 61:1669-1682. [PMID: 35895105 DOI: 10.1021/acs.biochem.2c00224] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
FOXO1, a member of the family of winged-helix motif Forkhead box (FOX) transcription factors, is the most abundantly expressed FOXO member in mature B cells. Sequencing of diffuse large B-cell lymphoma (DLBCL) tumors and cell lines identified specific mutations in the forkhead domain linked to loss of function. Differential scanning calorimetry and thermal shift assays were used to characterize how eight of these mutations affect the stability of the FOX domain. Mutations L183P and L183R were found to be particularly destabilizing. Electrophoresis mobility shift assays show these same mutations also disrupt FOXO1 binding to their canonical DNA sequences, suggesting that the loss of function is due to destabilization of the folded structure. Computational modeling of the effect of mutations on FOXO1 folding was performed using alchemical free energy perturbation (FEP), and a Markov model of the entire folding reaction was constructed from massively parallel molecular simulations, which predicts folding pathways involving the late folding of helix α3. Although FEP can qualitatively predict the destabilization from L183 mutations, we find that a simple hydrophobic transfer model, combined with estimates of unfolded-state solvent-accessible surface areas from molecular simulations, is able to more accurately predict changes in folding free energies due to mutations. These results suggest that the atomic detail provided by simulations is important for the accurate prediction of mutational effects on folding stability. Corresponding disease-associated mutations in other FOX family members support further experimental and computational studies of the folding mechanism of FOX domains.
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Affiliation(s)
- Dylan Novack
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Lei Qian
- Department of Medical Genetics & Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, 3440 North Broad Street, Philadelphia, Pennsylvania 19140, United States
| | - Gwyneth Acker
- Department of Medical Genetics & Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, 3440 North Broad Street, Philadelphia, Pennsylvania 19140, United States
| | - Vincent A Voelz
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Richard H G Baxter
- Department of Medical Genetics & Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, 3440 North Broad Street, Philadelphia, Pennsylvania 19140, United States
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7
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Silva BM, Santos LH, de Almeida JPP, de Magalhães MTQ. Rad5 HIRAN domain: Structural insights into its interaction with ssDNA through molecular modeling approaches. J Biomol Struct Dyn 2022; 41:3062-3075. [PMID: 35249470 DOI: 10.1080/07391102.2022.2045222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The Rad5 protein is an SWI/SNF family ubiquitin ligase that contains an N-terminal HIRAN domain and a RING C3HC4 motif. The HIRAN domain is critical for recognition of the stalled replication fork during the replication process and acts as a sensor to initiate the damaged DNA checkpoint. It is a conserved domain widely distributed in eukaryotic organisms and is present in several DNA-binding proteins from all kingdoms. Here we showed that distant species have important differences in key residues that affect affinity for ssDNA. Based on these findings, we hypothesized that different HIRAN domains might affect fork reversal and translesion synthesis through different metabolic processes. To address this question, we predicted the tertiary structure of both yeast and human HIRAN domains using molecular modeling. Structural dynamics experiments showed that the yeast HIRAN domain exhibited higher structural denaturation than its human homolog, although both domains became stable in the presence of ssDNA. Analysis of atomic contacts revealed that a greater number of interactions between the ssDNA nucleotides and the Rad5 domain are electrostatic. Taken together, these results provide new insights into the molecular mechanism of the HIRAN domain of Rad5 and may guide us to further elucidate differences in the ancient eukaryotes HIRAN sequences and their DNA affinity. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Bruno M Silva
- Inter-unit postgraduate studies program in Bioinformatics, Federal University of Minas Gerais, Instituto de Ciências Biológicas, Belo Horizonte, Brazil.,Macromolecular Biophysics Laboratory (LBM), Biological Sciences Institute (ICB), Federal University of Minas Gerais, Instituto de Ciências Biológicas, Belo Horizonte, Brazil
| | - Lucianna H Santos
- Inter-unit postgraduate studies program in Bioinformatics, Federal University of Minas Gerais, Instituto de Ciências Biológicas, Belo Horizonte, Brazil.,Molecular Modeling and Drug Planning Laboratory, Department of Biochemistry and Immunology, Biological Sciences Institute (ICB), Federal University of Minas Gerais, Instituto de Ciências Biológicas, Belo Horizonte, Brazil
| | - João Paulo P de Almeida
- Inter-unit postgraduate studies program in Bioinformatics, Federal University of Minas Gerais, Instituto de Ciências Biológicas, Belo Horizonte, Brazil
| | - Mariana T Q de Magalhães
- Inter-unit postgraduate studies program in Bioinformatics, Federal University of Minas Gerais, Instituto de Ciências Biológicas, Belo Horizonte, Brazil.,Macromolecular Biophysics Laboratory (LBM), Biological Sciences Institute (ICB), Federal University of Minas Gerais, Instituto de Ciências Biológicas, Belo Horizonte, Brazil
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8
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Bittner JP, Huang L, Zhang N, Kara S, Jakobtorweihen S. Comparison and Validation of Force Fields for Deep Eutectic Solvents in Combination with Water and Alcohol Dehydrogenase. J Chem Theory Comput 2021; 17:5322-5341. [PMID: 34232662 DOI: 10.1021/acs.jctc.1c00274] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Deep eutectic solvents (DESs) have become popular as environmental-friendly solvents for biocatalysis. Molecular dynamics (MD) simulations offer an in-depth analysis of enzymes in DESs, but their performance depends on the force field chosen. Here, we present a comprehensive validation of three biomolecular force fields (CHARMM, Amber, and OPLS) for simulations of alcohol dehydrogenase (ADH) in DESs composed of choline chloride and glycerol/ethylene glycol with varying water contents. Different properties (e.g., protein structure and flexibility, solvation layer, and H-bonds) were used for validation. For two properties (viscosity and water activity) also experiments were performed. The viscosity was calculated with the periodic perturbation method, whereby its parameter dependency is disclosed. A modification of Amber was identified as the best-performing model for low water contents, whereas CHARMM outperforms the other models at larger water concentrations. An analysis of ADH's structure and interactions with the DESs revealed similar predictions for Amber and CHARMM.
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Affiliation(s)
- Jan Philipp Bittner
- Institute of Thermal Separation Processes, Hamburg University of Technology, Eißendorfer Straße 38, 21073 Hamburg, Germany
| | - Lei Huang
- Department of Biological and Chemical Engineering, Biocatalysis and Bioprocessing Group, Aarhus University, Gustav Wieds Vej 10, 8000 Aarhus, Denmark
| | - Ningning Zhang
- Department of Biological and Chemical Engineering, Biocatalysis and Bioprocessing Group, Aarhus University, Gustav Wieds Vej 10, 8000 Aarhus, Denmark
| | - Selin Kara
- Department of Biological and Chemical Engineering, Biocatalysis and Bioprocessing Group, Aarhus University, Gustav Wieds Vej 10, 8000 Aarhus, Denmark
| | - Sven Jakobtorweihen
- Institute of Thermal Separation Processes, Hamburg University of Technology, Eißendorfer Straße 38, 21073 Hamburg, Germany.,Department for Chemical Reaction Engineering, Hamburg University of Technology, Eißendorfer Straße 38, 21073 Hamburg, Germany
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9
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La Sala G, Gunnarsson A, Edman K, Tyrchan C, Hogner A, Frolov AI. Unraveling the Allosteric Cross-Talk between the Coactivator Peptide and the Ligand-Binding Site in the Glucocorticoid Receptor. J Chem Inf Model 2021; 61:3667-3680. [PMID: 34156843 DOI: 10.1021/acs.jcim.1c00323] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The glucocorticoid receptor (GR) is a nuclear receptor that controls critical biological processes by regulating the transcription of specific genes. There is a known allosteric cross-talk between the ligand and coregulator binding sites within the GR ligand-binding domain that is crucial for the control of the functional response. However, the molecular mechanisms underlying such an allosteric control remain elusive. Here, molecular dynamics (MD) simulations, bioinformatic analysis, and biophysical measurements are integrated to capture the structural and dynamic features of the allosteric cross-talk within the GR. We identified a network of evolutionarily conserved residues that enables the allosteric signal transduction, in agreement with experimental data. MD simulations clarify how such a network is dynamically interconnected and offer a mechanistic explanation of how different peptides affect the intensity of the allosteric signal. This study provides useful insights to elucidate the GR allosteric regulation, ultimately providing a foundation for designing novel drugs.
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Affiliation(s)
- Giuseppina La Sala
- Medicinal Chemistry, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Anders Gunnarsson
- Discovery Science, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Karl Edman
- Discovery Science, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Christian Tyrchan
- Medicinal Chemistry, Research and Early Development, Respiratory & Immunology, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Anders Hogner
- Medicinal Chemistry, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Andrey I Frolov
- Medicinal Chemistry, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
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10
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Cupellini L, Calvani D, Jacquemin D, Mennucci B. Charge transfer from the carotenoid can quench chlorophyll excitation in antenna complexes of plants. Nat Commun 2020; 11:662. [PMID: 32005811 PMCID: PMC6994720 DOI: 10.1038/s41467-020-14488-6] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 01/09/2020] [Indexed: 12/31/2022] Open
Abstract
The photosynthetic apparatus of higher plants can dissipate excess excitation energy during high light exposure, by deactivating excited chlorophylls through a mechanism called nonphotochemical quenching (NPQ). However, the precise molecular details of quenching and the mechanism regulating the quenching level are still not completely understood. Focusing on the major light-harvesting complex LHCII of Photosystem II, we show that a charge transfer state involving Lutein can efficiently quench chlorophyll excitation, and reduce the excitation lifetime of LHCII to the levels measured in the deeply quenched LHCII aggregates. Through a combination of molecular dynamics simulations, multiscale quantum chemical calculations, and kinetic modeling, we demonstrate that the quenching level can be finely tuned by the protein, by regulating the energy of the charge transfer state. Our results suggest that a limited conformational rearrangement of the protein scaffold could act as a molecular switch to activate or deactivate the quenching mechanism.
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Affiliation(s)
- Lorenzo Cupellini
- Università di Pisa, Dipartimento di Chimica e Chimica Industriale, Via G. Moruzzi 13, 56124, Pisa, (PI), Italy.
| | - Dario Calvani
- Università di Pisa, Dipartimento di Chimica e Chimica Industriale, Via G. Moruzzi 13, 56124, Pisa, (PI), Italy
| | - Denis Jacquemin
- Laboratoire CEISAM-UMR CNRS 6230, Université de Nantes, 2 Rue de la Houssiniere, BP-92208, F-44322 Cedex 3, Nantes, France
| | - Benedetta Mennucci
- Università di Pisa, Dipartimento di Chimica e Chimica Industriale, Via G. Moruzzi 13, 56124, Pisa, (PI), Italy.
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11
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Lemkul JA. Pairwise-additive and polarizable atomistic force fields for molecular dynamics simulations of proteins. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2020; 170:1-71. [PMID: 32145943 DOI: 10.1016/bs.pmbts.2019.12.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Protein force fields have been undergoing continual development since the first complete parameter sets were introduced nearly four decades ago. The functional forms that underlie these models have many common elements for the treatment of bonded and nonbonded forces, which are reviewed here. The most widely used force fields to date use a fixed-charge convention in which electronic polarization effects are treated via a mean-field approximation during partial charge assignment. Despite success in modeling folded proteins over many years, the fixed-charge assumption has limitations that cannot necessarily be overcome within their potential energy equations. To overcome these limitations, several force fields have recently been derived that explicitly treat electronic polarization effects with straightforward extensions of the potential energy functions used by nonpolarizable force fields. Here, we review the history of the most popular nonpolarizable force fields (AMBER, CHARMM, OPLS, and GROMOS) as well as studies that have validated them and applied them to studies of protein folding and misfolding. Building upon these force fields are more recent polarizable interaction potentials, including fluctuating charge models, POSSIM, AMOEBA, and the classical Drude oscillator. These force fields differ in their implementations but all attempt to model electronic polarization in a computationally tractable manner. Despite their recent emergence in the field of protein folding, several studies have already applied these polarizable models to challenging problems in this domain, including the role of polarization in folding free energies and sequence-specific effects on the stability of α-helical structures.
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Affiliation(s)
- Justin A Lemkul
- Department of Biochemistry, Virginia Tech, Blacksburg, VA, United States.
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12
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Pereira GRC, Tellini GHAS, De Mesquita JF. In silico analysis of PFN1 related to amyotrophic lateral sclerosis. PLoS One 2019; 14:e0215723. [PMID: 31216283 PMCID: PMC6583998 DOI: 10.1371/journal.pone.0215723] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 04/09/2019] [Indexed: 12/11/2022] Open
Abstract
Profilin 1 (PFN1) protein plays key roles in neuronal growth and differentiation, membrane trafficking, and regulation of the actin cytoskeleton. Four natural variants of PFN1 were described as related to ALS, the most common adult-onset motor neuron disorder. However, the pathological mechanism of PFN1 in ALS is not yet completely understood. The goal of this work is to thoroughly analyze the effects of the ALS-related mutations on PFN1 structure and function using computational simulations. Here, PhD-SNP, PMUT, PolyPhen-2, SIFT, SNAP, SNPS&GO, SAAP, nsSNPAnalyzer, SNPeffect4.0 and I-Mutant2.0 were used to predict the functional and stability effects of PFN1 mutations. ConSurf was used for the evolutionary conservation analysis, and GROMACS was used to perform the MD simulations. The mutations C71G, M114T, and G118V, but not E117G, were predicted as deleterious by most of the functional prediction algorithms that were used. The stability prediction indicated that the ALS-related mutations could destabilize PFN1. The ConSurf analysis indicated that the mutation C71G, M114T, E117G, and G118V occur in highly conserved positions. The MD results indicated that the studied mutations could affect the PFN1 flexibility at the actin and PLP-binding domains, and consequently, their intermolecular interactions. It may be therefore related to the functional impairment of PFN1 upon C71G, M114T, E117G and G118V mutations, and their involvement in ALS development. We also developed a database, SNPMOL (http://www.snpmol.org/), containing the results presented on this paper for biologists and clinicians to exploit PFN1 and its natural variants.
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Affiliation(s)
- Gabriel Rodrigues Coutinho Pereira
- Department of Genetics and Molecular Biology, Bioinformatics and Computational Biology Laboratory, Federal University of the State of Rio de Janeiro (UNIRIO), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Giovanni Henrique Almeida Silva Tellini
- Department of Genetics and Molecular Biology, Bioinformatics and Computational Biology Laboratory, Federal University of the State of Rio de Janeiro (UNIRIO), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Joelma Freire De Mesquita
- Department of Genetics and Molecular Biology, Bioinformatics and Computational Biology Laboratory, Federal University of the State of Rio de Janeiro (UNIRIO), Rio de Janeiro, Rio de Janeiro, Brazil
- * E-mail:
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