1
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Nagarajan SK, Babu S, Devaraju P, Sohn H, Madhavan T. Structure and dynamics of the somatostatin receptor 3-ligand binding in the presence of lipids examined using computational structural biology methods. Proteins 2022; 90:704-719. [PMID: 34661304 DOI: 10.1002/prot.26267] [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: 03/01/2021] [Revised: 09/29/2021] [Accepted: 10/12/2021] [Indexed: 11/08/2022]
Abstract
In the past two decades, the structural biology studies on G-protein coupled receptors (GPCRs) are on the rise. Understanding the relation between the structure and function of GPCRs is important as they play a huge role in various signaling mechanisms in a eukaryotic cell. Somatostatin receptor 3 (SSTR3), one of the GPCRs, is one such important receptor which oversees different cellular processes including cell-to-cell signaling. However, the information available regarding the structural features of SSTR3 responsible for their bioactivity is scarce. In this study, we report a structural understanding of SSTR3-ligand binding that could be helpful in demystifying the structural complexities related to functioning of the receptor. An integrated protocol consisting of different computational structural biology tools including protein structure prediction via comparative modeling, binding site characterization, three-dimensional quantitative structure-activity relationship based on comparative molecular field analysis and comparative molecular similarity indices analysis, density functional theory, and molecular dynamics simulations were performed. Different understandings from the simulation of SSTR3-ligand complexes, mainly the conditions that are favorable for the formation of lowest bioactive state of SSTR3 ligands are reported. In addition to that, we report the important physicochemical descriptors of SSTR3 ligands that could significantly influence their bioactivity. The results of the study could be helpful in developing novel SSTR3 ligands (both agonists and antagonists) with high potency and receptor selectivity.
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Affiliation(s)
- Santhosh Kumar Nagarajan
- Computational Biology Lab, Department of Genetic Engineering, School of Bioengineering, SRM Institute of Science and Technology, Chennai, India
| | - Sathya Babu
- Computational Biology Lab, Department of Genetic Engineering, School of Bioengineering, SRM Institute of Science and Technology, Chennai, India
| | - Panneer Devaraju
- Division of Microbiology and Molecular Biology, Vector Control Research Centre, Indian Council of Medical Research, Pondicherry, India
| | - Honglae Sohn
- Department of Chemistry, Chosun University, Gwangju, South Korea
- Department of Carbon Materials, Chosun University, Gwangju, South Korea
| | - Thirumurthy Madhavan
- Computational Biology Lab, Department of Genetic Engineering, School of Bioengineering, SRM Institute of Science and Technology, Chennai, India
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2
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Bitter taste in silico: A review on virtual ligand screening and characterization methods for TAS2R-bitterant interactions. Int J Pharm 2021; 600:120486. [PMID: 33744445 DOI: 10.1016/j.ijpharm.2021.120486] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/21/2021] [Accepted: 03/09/2021] [Indexed: 11/21/2022]
Abstract
The growing pharmaceutical interest in the human bitter taste receptors (hTAS2Rs) has two dimensions; i) evaluation of the bitterness of active pharmaceutical compounds, in order to develop strategies for improving patients' adherence to medication, and ii) application of ligands for extra-cellular hTAS2Rs for potential preventive therapeutic achievements. The result is an increasing demand on robust tools for bitterness assessment and screening the receptor-ligand affinity. In silico tools are useful for aiding experimental-screening, as well as to elucide ligand-receptor interactions. In this review, the ligand-based and structure-based approaches are described as the two main in silico tools for bitter taste analysis. The strengths and weaknesses of each approach are discussed. Both approaches provide key tools for understanding and exploiting bitter taste for human health applications.
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3
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Nagarajan S, Babu S, Sohn H, Madhavan T. Molecular-Level Understanding of the Somatostatin Receptor 1 (SSTR1)-Ligand Binding: A Structural Biology Study Based on Computational Methods. ACS OMEGA 2020; 5:21145-21161. [PMID: 32875251 PMCID: PMC7450625 DOI: 10.1021/acsomega.0c02847] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 07/31/2020] [Indexed: 06/11/2023]
Abstract
Somatostatin receptor 1 (SSTR1), a subtype of somatostatin receptors, is involved in various signaling mechanisms in different parts of the human body. Like most of the G-protein-coupled receptors (GPCRs), the available information on the structural features of SSTR1 responsible for the biological activity is scarce. In this study, we report a molecular-level understanding of SSTR1-ligand binding, which could be helpful in solving the structural complexities involved in SSTR1 functioning. Based on a three-dimensional quantitative structure-activity relationship (3D-QSAR) study using comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA), we have identified that an electronegative, less-bulkier, and hydrophobic atom substitution can substantially increase the biological activity of SSTR1 ligands. A density functional theory (DFT) study has been followed to study the electron-related properties of the SSTR1 ligands and to validate the results obtained via the 3D-QSAR study. 3D models of SSTR1-ligand systems have been embedded in lipid-lipid bilayer membranes to perform molecular dynamics (MD) simulations. Analysis of the MD trajectories reveals important information about the crucial residues involved in SSTR1-ligand binding and various conformational changes in the protein that occur after ligand binding. Additionally, we have identified the probable ligand-binding site of SSTR1 and validated it using MD. We have also studied the favorable conditions that are essential for forming the most stable and lowest-energy bioactive conformation of the ligands inside the binding site. The results of the study could be useful in constructing more potent and novel SSTR1 antagonists and agonists.
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Affiliation(s)
- Santhosh
Kumar Nagarajan
- Computational
Biology Lab, Department of Genetic Engineering, School of Bioengineering, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Chennai 603203, India
| | - Sathya Babu
- Computational
Biology Lab, Department of Genetic Engineering, School of Bioengineering, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Chennai 603203, India
| | - Honglae Sohn
- Department
of Chemistry and Department of Carbon Materials, Chosun University, Gwangju, South Korea
| | - Thirumurthy Madhavan
- Computational
Biology Lab, Department of Genetic Engineering, School of Bioengineering, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Chennai 603203, India
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4
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Development of the first in vivo GPR17 ligand through an iterative drug discovery pipeline: A novel disease-modifying strategy for multiple sclerosis. PLoS One 2020; 15:e0231483. [PMID: 32320409 PMCID: PMC7176092 DOI: 10.1371/journal.pone.0231483] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 03/24/2020] [Indexed: 01/09/2023] Open
Abstract
The GPR17 receptor, expressed on oligodendroglial precursors (OPCs, the myelin producing cells), has emerged as an attractive target for a pro-myelinating strategy in multiple sclerosis (MS). However, the proof-of-concept that selective GPR17 ligands actually exert protective activity in vivo is still missing. Here, we exploited an iterative drug discovery pipeline to prioritize novel and selective GPR17 pro-myelinating agents out of more than 1,000,000 compounds. We first performed an in silico high-throughput screening on GPR17 structural model to identify three chemically-diverse ligand families that were then combinatorially exploded and refined. Top-scoring compounds were sequentially tested on reference pharmacological in vitro assays with increasing complexity, ending with myelinating OPC-neuron co-cultures. Successful ligands were filtered through in silico simulations of metabolism and pharmacokinetics, to select the most promising hits, whose dose and ability to target the central nervous system were then determined in vivo. Finally, we show that, when administered according to a preventive protocol, one of them (named by us as galinex) is able to significantly delay the onset of experimental autoimmune encephalomyelitis (EAE), a mouse model of MS. This outcome validates the predictivity of our pipeline to identify novel MS-modifying agents.
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5
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Jakubik J, El-Fakahany EE. Current Advances in Allosteric Modulation of Muscarinic Receptors. Biomolecules 2020; 10:biom10020325. [PMID: 32085536 PMCID: PMC7072599 DOI: 10.3390/biom10020325] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 02/14/2020] [Accepted: 02/16/2020] [Indexed: 02/07/2023] Open
Abstract
Allosteric modulators are ligands that bind to a site on the receptor that is spatially separated from the orthosteric binding site for the endogenous neurotransmitter. Allosteric modulators modulate the binding affinity, potency, and efficacy of orthosteric ligands. Muscarinic acetylcholine receptors are prototypical allosterically-modulated G-protein-coupled receptors. They are a potential therapeutic target for the treatment of psychiatric, neurologic, and internal diseases like schizophrenia, Alzheimer’s disease, Huntington disease, type 2 diabetes, or chronic pulmonary obstruction. Here, we reviewed the progress made during the last decade in our understanding of their mechanisms of binding, allosteric modulation, and in vivo actions in order to understand the translational impact of studying this important class of pharmacological agents. We overviewed newly developed allosteric modulators of muscarinic receptors as well as new spin-off ideas like bitopic ligands combining allosteric and orthosteric moieties and photo-switchable ligands based on bitopic agents.
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Affiliation(s)
- Jan Jakubik
- Department of Neurochemistry, Institute of Physiology CAS, 142 20 Prague, Czech Republic
- Correspondence: (J.J.); (E.E.E.-F.)
| | - Esam E. El-Fakahany
- Department of Experimental and Clinical Pharmacology, University of Minnesota College of Pharmacy, Minneapolis, MN 55455, USA
- Correspondence: (J.J.); (E.E.E.-F.)
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6
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Bermudez M, Nguyen TN, Omieczynski C, Wolber G. Strategies for the discovery of biased GPCR ligands. Drug Discov Today 2019; 24:1031-1037. [PMID: 30831262 DOI: 10.1016/j.drudis.2019.02.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 02/13/2019] [Accepted: 02/25/2019] [Indexed: 02/07/2023]
Abstract
G-protein-coupled receptors (GPCRs) represent important drug targets with complex pharmacological characteristics. Biased signaling represents one important dimension, describing ligand-dependent shifts of naturally imprinted signaling profiles. Because biased GPCR modulators provide potential therapeutic benefits including higher efficiencies and reduced adverse effects, the identification of such ligands as drug candidates is highly desirable. This review aims to provide an overview of the challenges and strategies in the discovery of biased ligands. We show different approaches for biased ligand discovery in the example of G-protein-biased opioid analgesics and discuss possibilities to design biased ligands by targeting extracellular receptor regions.
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Affiliation(s)
- Marcel Bermudez
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Straße 2+4, 14195 Berlin, Germany.
| | - Trung Ngoc Nguyen
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Straße 2+4, 14195 Berlin, Germany
| | - Christian Omieczynski
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Straße 2+4, 14195 Berlin, Germany
| | - Gerhard Wolber
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Straße 2+4, 14195 Berlin, Germany
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7
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Holland CJ, MacLachlan BJ, Bianchi V, Hesketh SJ, Morgan R, Vickery O, Bulek AM, Fuller A, Godkin A, Sewell AK, Rizkallah PJ, Wells S, Cole DK. In Silico and Structural Analyses Demonstrate That Intrinsic Protein Motions Guide T Cell Receptor Complementarity Determining Region Loop Flexibility. Front Immunol 2018; 9:674. [PMID: 29696015 PMCID: PMC5904202 DOI: 10.3389/fimmu.2018.00674] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 03/19/2018] [Indexed: 11/13/2022] Open
Abstract
T-cell immunity is controlled by T cell receptor (TCR) binding to peptide major histocompatibility complexes (pMHCs). The nature of the interaction between these two proteins has been the subject of many investigations because of its central role in immunity against pathogens, cancer, in autoimmunity, and during organ transplant rejection. Crystal structures comparing unbound and pMHC-bound TCRs have revealed flexibility at the interaction interface, particularly from the perspective of the TCR. However, crystal structures represent only a snapshot of protein conformation that could be influenced through biologically irrelevant crystal lattice contacts and other factors. Here, we solved the structures of three unbound TCRs from multiple crystals. Superposition of identical TCR structures from different crystals revealed some conformation differences of up to 5 Å in individual complementarity determining region (CDR) loops that are similar to those that have previously been attributed to antigen engagement. We then used a combination of rigidity analysis and simulations of protein motion to reveal the theoretical potential of TCR CDR loop flexibility in unbound state. These simulations of protein motion support the notion that crystal structures may only offer an artifactual indication of TCR flexibility, influenced by crystallization conditions and crystal packing that is inconsistent with the theoretical potential of intrinsic TCR motions.
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Affiliation(s)
- Christopher J Holland
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom.,Immunocore, Abingdon, United Kingdom
| | - Bruce J MacLachlan
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Valentina Bianchi
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom.,Department of Oncology, University Hospital of Lausanne, Lausanne, Switzerland
| | - Sophie J Hesketh
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom.,Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Richard Morgan
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Owen Vickery
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Anna M Bulek
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Anna Fuller
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Andrew Godkin
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Andrew K Sewell
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Pierre J Rizkallah
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Stephen Wells
- Department of Chemistry, University of Bath, Bath, United Kingdom
| | - David K Cole
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom.,Immunocore, Abingdon, United Kingdom
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8
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Abstract
Despite tremendous efforts, approximately 120 GPCRs remain orphan. Their physiological functions and their potential roles in diseases are poorly understood. Orphan GPCRs are extremely important because they may provide novel therapeutic targets for unmet medical needs. As a complement to experimental approaches, molecular modeling and virtual screening are efficient techniques to discover synthetic surrogate ligands which can help to elucidate the role of oGPCRs. Constitutively activated mutants and recently published active structures of GPCRs provide stimulating opportunities for building active molecular models for oGPCRs and identifying activators using virtual screening of compound libraries. We describe the molecular modeling and virtual screening process we have applied in the discovery of surrogate ligands, and provide examples for CCKA, a simulated oGPCR, and for two oGPCRs, GPR52 and GPR34.
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Affiliation(s)
- Constantino Diaz
- Research Informatics, Evotec (France) SAS, 195 Route d'Espagne, 31036, Toulouse, France.
| | | | - Emilie Pihan
- Research Informatics, Evotec (France) SAS, 195 Route d'Espagne, 31036, Toulouse, France
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9
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Ligand binding modes from low resolution GPCR models and mutagenesis: chicken bitter taste receptor as a test-case. Sci Rep 2017; 7:8223. [PMID: 28811548 PMCID: PMC5557796 DOI: 10.1038/s41598-017-08344-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 07/10/2017] [Indexed: 11/08/2022] Open
Abstract
Bitter taste is one of the basic taste modalities, warning against consuming potential poisons. Bitter compounds activate members of the bitter taste receptor (Tas2r) subfamily of G protein-coupled receptors (GPCRs). The number of functional Tas2rs is species-dependent. Chickens represent an intriguing minimalistic model, because they detect the bitter taste of structurally different molecules with merely three bitter taste receptor subtypes. We investigated the binding modes of several known agonists of a representative chicken bitter taste receptor, ggTas2r1. Because of low sequence similarity between ggTas2r1 and crystallized GPCRs (~10% identity, ~30% similarity at most), the combination of computational approaches with site-directed mutagenesis was used to characterize the agonist-bound conformation of ggTas2r1 binding site between TMs 3, 5, 6 and 7. We found that the ligand interactions with N93 in TM3 and/or N247 in TM5, combined with hydrophobic contacts, are typically involved in agonist recognition. Next, the ggTas2r1 structural model was successfully used to identify three quinine analogues (epiquinidine, ethylhydrocupreine, quinidine) as new ggTas2r1 agonists. The integrated approach validated here may be applicable to additional cases where the sequence identity of the GPCR of interest and the existing experimental structures is low.
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10
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Bermudez M, Bock A, Krebs F, Holzgrabe U, Mohr K, Lohse MJ, Wolber G. Ligand-Specific Restriction of Extracellular Conformational Dynamics Constrains Signaling of the M 2 Muscarinic Receptor. ACS Chem Biol 2017; 12:1743-1748. [PMID: 28585805 DOI: 10.1021/acschembio.7b00275] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
G protein-coupled receptors transmit extracellular signals across cell membranes via different G protein classes and β-arrestins. Some pathways may be therapeutically beneficial, whereas others may be detrimental under certain pathophysiological conditions. For many GPCRs, biased agonists are available, which preferentially signal through one pathway or a subset of pathways, and harnessing biased agonism could be a potential novel therapeutic strategy. However, the incomplete mechanistic understanding of biased agonism hampers rational design of biased ligands. Using the muscarinic M2 receptor as a model system, we have analyzed the relationship between ligand-dependent conformational changes as revealed in all-atom MD simulations and the activation of specific G proteins. We find that the extent of closure of the extracellular, allosteric binding site interferes with the activation of certain G proteins. Our data allow the rational design of Gi-biased agonists at the M2 receptor and delineate a simple principle which may be translated to other GPRCs.
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Affiliation(s)
- Marcel Bermudez
- Institute
of Pharmacy, Freie Universität Berlin, Königin-Luise-Straße
2 und 4, 14195 Berlin, Germany
| | - Andreas Bock
- Institute
of Pharmacology and Toxicology, University of Würzburg, Versbacher
Strasse 9, 97078 Würzburg, Germany
- Max Delbrück Center for Molecular Medicine, Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Fabian Krebs
- Pharmacology
and Toxicology Section, Institute of Pharmacy, University of Bonn, Gerhard-Domagk-Straße 3, 53121 Bonn, Germany
| | - Ulrike Holzgrabe
- Institute
of Pharmacy, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Klaus Mohr
- Pharmacology
and Toxicology Section, Institute of Pharmacy, University of Bonn, Gerhard-Domagk-Straße 3, 53121 Bonn, Germany
| | - Martin J. Lohse
- Institute
of Pharmacology and Toxicology, University of Würzburg, Versbacher
Strasse 9, 97078 Würzburg, Germany
- Max Delbrück Center for Molecular Medicine, Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Gerhard Wolber
- Institute
of Pharmacy, Freie Universität Berlin, Königin-Luise-Straße
2 und 4, 14195 Berlin, Germany
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11
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Ahrendt SR, Medina EM, Chang CEA, Stajich JE. Exploring the binding properties and structural stability of an opsin in the chytrid Spizellomyces punctatus using comparative and molecular modeling. PeerJ 2017; 5:e3206. [PMID: 28462022 PMCID: PMC5410147 DOI: 10.7717/peerj.3206] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 03/20/2017] [Indexed: 01/16/2023] Open
Abstract
Background Opsin proteins are seven transmembrane receptor proteins which detect light. Opsins can be classified into two types and share little sequence identity: type 1, typically found in bacteria, and type 2, primarily characterized in metazoa. The type 2 opsins (Rhodopsins) are a subfamily of G-protein coupled receptors (GPCRs), a large and diverse class of seven transmembrane proteins and are generally restricted to metazoan lineages. Fungi use light receptors including opsins to sense the environment and transduce signals for developmental or metabolic changes. Opsins characterized in the Dikarya (Ascomycetes and Basidiomycetes) are of the type 1 bacteriorhodopsin family but the early diverging fungal lineages have not been as well surveyed. We identified by sequence similarity a rhodopsin-like GPCR in genomes of early diverging chytrids and examined the structural characteristics of this protein to assess its likelihood to be homologous to animal rhodopsins and bind similar chromophores. Methods We used template-based structure modeling, automated ligand docking, and molecular modeling to assess the structural and binding properties of an identified opsin-like protein found in Spizellomyces punctatus, a unicellular, flagellated species belonging to Chytridiomycota, one of the earliest diverging fungal lineages. We tested if the sequence and inferred structure were consistent with a solved crystal structure of a type 2 rhodopsin from the squid Todarodes pacificus. Results Our results indicate that the Spizellomyces opsin has structural characteristics consistent with functional animal type 2 rhodopsins and is capable of maintaining a stable structure when associated with the retinaldehyde chromophore, specifically the 9-cis-retinal isomer. Together, these results support further the homology of Spizellomyces opsins to animal type 2 rhodopsins. Discussion This represents the first test of structure/function relationship of a type 2 rhodopsin identified in early branching fungal lineages, and provides a foundation for future work exploring pathways and components of photoreception in early fungi.
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Affiliation(s)
- Steven R Ahrendt
- Department of Plant Pathology & Microbiology, University of California, Riverside, CA, USA.,Institute for Integrative Genome Biology, University of California, Riverside, CA, USA.,Genetics, Genomics, and Bioinformatics Program, University of California, Riverside, CA, USA
| | - Edgar Mauricio Medina
- Department of Biology, Duke University, Durham, NC, USA.,Center for Genomic and Computational Biology, Duke University, Durham, NC, USA
| | - Chia-En A Chang
- Institute for Integrative Genome Biology, University of California, Riverside, CA, USA.,Department of Chemistry, University of California, Riverside, CA, USA
| | - Jason E Stajich
- Department of Plant Pathology & Microbiology, University of California, Riverside, CA, USA.,Institute for Integrative Genome Biology, University of California, Riverside, CA, USA
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12
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Heifetz A, James T, Morao I, Bodkin MJ, Biggin PC. Guiding lead optimization with GPCR structure modeling and molecular dynamics. Curr Opin Pharmacol 2016; 30:14-21. [DOI: 10.1016/j.coph.2016.06.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 06/16/2016] [Accepted: 06/17/2016] [Indexed: 01/04/2023]
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13
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Blinded predictions of binding modes and energies of HSP90-α ligands for the 2015 D3R grand challenge. Bioorg Med Chem 2016; 24:4890-4899. [DOI: 10.1016/j.bmc.2016.07.044] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 07/19/2016] [Accepted: 07/20/2016] [Indexed: 01/14/2023]
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14
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Guerrieri E, Bermudez M, Wolber G, Berzetei-Gurske IP, Schmidhammer H, Spetea M. Structural determinants of diphenethylamines for interaction with the κ opioid receptor: Synthesis, pharmacology and molecular modeling studies. Bioorg Med Chem Lett 2016; 26:4769-4774. [PMID: 27567368 DOI: 10.1016/j.bmcl.2016.08.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 08/10/2016] [Accepted: 08/11/2016] [Indexed: 10/21/2022]
Abstract
The κ opioid (KOP) receptor crystal structure in an inactive state offers nowadays a valuable platform for inquiry into receptor function. We describe the synthesis, pharmacological evaluation and docking calculations of KOP receptor ligands from the class of diphenethylamines using an active-like structure of the KOP receptor attained by molecular dynamics simulations. The structure-activity relationships derived from computational studies was in accordance with pharmacological activities of targeted diphenethylamines at the KOP receptor established by competition binding and G protein activation in vitro assays. Our analysis identified that agonist binding results in breaking of the Arg156-Thr273 hydrogen bond, which stabilizes the inactive receptor conformation, and a crucial hydrogen bond with His291 is formed. Compounds with a phenolic 4-hydroxy group do not form the hydrogen bond with His291, an important residue for KOP affinity and agonist activity. The size of the N-substituent hosted by the hydrophobic pocket formed by Val108, Ile316 and Tyr320 considerably influences binding and selectivity, with the n-alkyl size limit being five carbon atoms, while bulky substituents turn KOP agonists in antagonists. Thus, combination of experimental and molecular modeling strategies provides an initial framework for understanding the structural features of diphenethylamines that are essential to promote binding affinity and selectivity for the KOP receptor, and may be involved in transduction of the ligand binding event into molecular changes, ultimately leading to receptor activation.
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Affiliation(s)
- Elena Guerrieri
- Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Marcel Bermudez
- Institute of Pharmacy, Freie Universität Berlin, D-14195 Berlin, Germany
| | - Gerhard Wolber
- Institute of Pharmacy, Freie Universität Berlin, D-14195 Berlin, Germany
| | - Ilona P Berzetei-Gurske
- Biosciences Division, SRI International, 333 Ravenswood Avenue, Menlo Park, CA 94025, United States
| | - Helmut Schmidhammer
- Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Mariana Spetea
- Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria.
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15
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Bock A, Bermudez M, Krebs F, Matera C, Chirinda B, Sydow D, Dallanoce C, Holzgrabe U, De Amici M, Lohse MJ, Wolber G, Mohr K. Ligand Binding Ensembles Determine Graded Agonist Efficacies at a G Protein-coupled Receptor. J Biol Chem 2016; 291:16375-89. [PMID: 27298318 PMCID: PMC4965584 DOI: 10.1074/jbc.m116.735431] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 06/07/2016] [Indexed: 11/06/2022] Open
Abstract
G protein-coupled receptors constitute the largest family of membrane receptors and modulate almost every physiological process in humans. Binding of agonists to G protein-coupled receptors induces a shift from inactive to active receptor conformations. Biophysical studies of the dynamic equilibrium of receptors suggest that a portion of receptors can remain in inactive states even in the presence of saturating concentrations of agonist and G protein mimetic. However, the molecular details of agonist-bound inactive receptors are poorly understood. Here we use the model of bitopic orthosteric/allosteric (i.e. dualsteric) agonists for muscarinic M2 receptors to demonstrate the existence and function of such inactive agonist·receptor complexes on a molecular level. Using all-atom molecular dynamics simulations, dynophores (i.e. a combination of static three-dimensional pharmacophores and molecular dynamics-based conformational sampling), ligand design, and receptor mutagenesis, we show that inactive agonist·receptor complexes can result from agonist binding to the allosteric vestibule alone, whereas the dualsteric binding mode produces active receptors. Each agonist forms a distinct ligand binding ensemble, and different agonist efficacies depend on the fraction of purely allosteric (i.e. inactive) versus dualsteric (i.e. active) binding modes. We propose that this concept may explain why agonist·receptor complexes can be inactive and that adopting multiple binding modes may be generalized also to small agonists where binding modes will be only subtly different and confined to only one binding site.
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Affiliation(s)
- Andreas Bock
- From the Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Strasse 9, 97078 Würzburg, Germany,
| | - Marcel Bermudez
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Strasse 2 und 4, 14195 Berlin, Germany,
| | - Fabian Krebs
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Gerhard-Domagk-Strasse 3, 53121 Bonn, Germany
| | - Carlo Matera
- Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica "Pietro Pratesi," Università degli Studi di Milano, Via Mangiagalli 25, 20133 Milan, Italy, and
| | - Brian Chirinda
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Gerhard-Domagk-Strasse 3, 53121 Bonn, Germany
| | - Dominique Sydow
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Strasse 2 und 4, 14195 Berlin, Germany
| | - Clelia Dallanoce
- Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica "Pietro Pratesi," Università degli Studi di Milano, Via Mangiagalli 25, 20133 Milan, Italy, and
| | - Ulrike Holzgrabe
- Institute of Pharmacy, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Marco De Amici
- Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica "Pietro Pratesi," Università degli Studi di Milano, Via Mangiagalli 25, 20133 Milan, Italy, and
| | - Martin J Lohse
- From the Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Strasse 9, 97078 Würzburg, Germany
| | - Gerhard Wolber
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Strasse 2 und 4, 14195 Berlin, Germany
| | - Klaus Mohr
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Gerhard-Domagk-Strasse 3, 53121 Bonn, Germany,
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16
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Bermudez M, Mortier J, Rakers C, Sydow D, Wolber G. More than a look into a crystal ball: protein structure elucidation guided by molecular dynamics simulations. Drug Discov Today 2016; 21:1799-1805. [PMID: 27417339 DOI: 10.1016/j.drudis.2016.07.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 05/20/2016] [Accepted: 07/04/2016] [Indexed: 10/21/2022]
Abstract
The 'form follows function' principle implies that a structural determination of protein structures is indispensable to understand proteins in their biological roles. However, experimental methods still show shortcomings in the description of the dynamic properties of proteins. Therefore, molecular dynamics (MD) simulations represent an essential tool for structural biology to investigate proteins as flexible and dynamic entities. Here, we will give an overview on the impact of MD simulations on structural investigations, including studies that aim at a prediction of protein-folding pathways, protein-assembly processes and the sampling of conformational space by computational means.
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Affiliation(s)
- Marcel Bermudez
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Straße 2+4, 14195 Berlin, Germany.
| | - Jeremie Mortier
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Straße 2+4, 14195 Berlin, Germany
| | - Christin Rakers
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Straße 2+4, 14195 Berlin, Germany
| | - Dominique Sydow
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Straße 2+4, 14195 Berlin, Germany
| | - Gerhard Wolber
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Straße 2+4, 14195 Berlin, Germany
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17
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Rodríguez-Espigares I, Kaczor AA, Selent J. In silico Exploration of the Conformational Universe of GPCRs. Mol Inform 2016; 35:227-37. [PMID: 27492237 DOI: 10.1002/minf.201600012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 04/14/2016] [Indexed: 12/17/2022]
Abstract
The structural plasticity of G protein coupled receptors (GPCRs) leads to a conformational universe going from inactive to active receptor states with several intermediate states. Many of them have not been captured yet and their role for GPCR activation is not well understood. The study of this conformational space and the transition dynamics between different receptor populations is a major challenge in molecular biophysics. The rational design of effector molecules that target such receptor populations allows fine-tuning receptor signalling with higher specificity to produce drugs with safer therapeutic profiles. In this minireview, we outline highly conserved receptor regions which are considered determinant for the establishment of distinct receptor states. We then discuss in-silico approaches such as dimensionality reduction methods and Markov State Models to explore the GPCR conformational universe and exploit the obtained conformations through structure-based drug design.
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Affiliation(s)
- Ismael Rodríguez-Espigares
- Pharmacoinformatics group, Research Programme on Biomedical Informatics (GRIB), Universitat Pompeu Fabra (UPF)-Hospital del Mar Medical Research Institute (IMIM), Parc de Recerca Biomèdica de Barcelona (PRBB), Dr. Aiguader, 88, 08003, Barcelona, Spain
| | - Agnieszka A Kaczor
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances with Computer Modeling Lab, Faculty of Pharmacy with Division for Medical Analytics, Medical University of Lublin, 4A Chodźki St., PL-20059, Lublin, Poland.,School of Pharmacy, University of Eastern Finland, Yliopistonranta 1, P.O. Box 1627, FI-70211, Kuopio, Finland
| | - Jana Selent
- Pharmacoinformatics group, Research Programme on Biomedical Informatics (GRIB), Universitat Pompeu Fabra (UPF)-Hospital del Mar Medical Research Institute (IMIM), Parc de Recerca Biomèdica de Barcelona (PRBB), Dr. Aiguader, 88, 08003, Barcelona, Spain.
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18
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Biggin PC, Aldeghi M, Bodkin MJ, Heifetz A. Beyond Membrane Protein Structure: Drug Discovery, Dynamics and Difficulties. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 922:161-181. [PMID: 27553242 DOI: 10.1007/978-3-319-35072-1_12] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Most of the previous content of this book has focused on obtaining the structures of membrane proteins. In this chapter we explore how those structures can be further used in two key ways. The first is their use in structure based drug design (SBDD) and the second is how they can be used to extend our understanding of their functional activity via the use of molecular dynamics. Both aspects now heavily rely on computations. This area is vast, and alas, too large to consider in depth in a single book chapter. Thus where appropriate we have referred the reader to recent reviews for deeper assessment of the field. We discuss progress via the use of examples from two main drug target areas; G-protein coupled receptors (GPCRs) and ion channels. We end with a discussion of some of the main challenges in the area.
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Affiliation(s)
- Philip C Biggin
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK.
| | - Matteo Aldeghi
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - Michael J Bodkin
- Evotec Ltd, 114 Innovation Drive, Milton Park, Abingdon, Oxfordshire, OX14 4RZ, UK
| | - Alexander Heifetz
- Evotec Ltd, 114 Innovation Drive, Milton Park, Abingdon, Oxfordshire, OX14 4RZ, UK
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