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Zhang W, Zhao C, Zhu W, He X, Zhao Y. Conformational Locking as a Strategy to Reverse Ion Recognition Selectivity. J Org Chem 2024; 89:4037-4041. [PMID: 38389323 DOI: 10.1021/acs.joc.3c02902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
This study delves into the ion recognition capabilities of a novel host molecule, emphasizing the role of conformational locking in dictating ion selectivity. By employing the Buchwald-Hartwig cross-coupling reaction, we have notably shifted the ion receptor's selectivity from K+ to Na+. The findings are supported by computational simulations that reveal differences in binding energies and molecular strain impacting ion recognition. This innovative structural modification broadens the scope for alterations at the calix[4]arene's lower rim, paving the way for new methods and strategies in modulating ion recognition selectivity.
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Affiliation(s)
- Wei Zhang
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610068, China
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Chong Zhao
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, Shanghai Frontiers Science Center of Molecule Intelligent Syntheses, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Wenjie Zhu
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Xiao He
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, Shanghai Frontiers Science Center of Molecule Intelligent Syntheses, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Yanchuan Zhao
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610068, China
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, China
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2
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Growth performance, nutrient digestibility, blood profile, gut health and La deposition of weaning rabbits fed with a low dosage of La2O3. Livest Sci 2023. [DOI: 10.1016/j.livsci.2023.105180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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3
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A novel dual three and five-component reactions between dimedone, aryl aldehydes, and 1-naphthylamine: synthesis and computational studies. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.132569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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4
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Rogachevskii IV, Plakhova VB, Penniyaynen VA, Terekhin SG, Podzorova SA, Krylov BV. New approaches to the design of analgesic medicinal substances. Can J Physiol Pharmacol 2021; 100:43-52. [PMID: 34425056 DOI: 10.1139/cjpp-2021-0286] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A gamma-pyrone derivative, comenic acid, activates the opioid-like receptor-mediated signaling pathway that modulates the NaV1.8 channels in the primary sensory neuron membrane. These channels are responsible for the generation of the nociceptive signal; therefore, gamma-pyrones have great therapeutic potential as analgesics, and this effect deserves a deeper understanding. The novelty of our approach to the design of a medicinal substance is based on a combination of the data obtained from living neurons using very sensitive physiological methods and the results of quantum chemical calculations. This approach allows the correlation of the molecular structure of gamma-pyrones with their ability to evoke a physiological response of the neuron. Comenic acid can bind to two calcium cations. One of them is chelated by the carbonyl and hydroxyl functional groups, while the other forms a salt bond with the carboxylate anion. Calcium-bound gamma-pyrones have fundamentally different electrostatic properties from free gamma-pyrone molecules. These two calcium ions are key elements involved in ligand-receptor binding. It is very likely that ion-ionic interactions between these cations and anionic functional groups of the opioid-like receptor activate the latter. The calculated intercationic distance of 9.5 Å is a structural criterion for effective ligand-receptor binding of calcium-bound gamma-pyrones.
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Affiliation(s)
- Ilia V Rogachevskii
- Pavlov Institute of Physiology of the Russian Academy of Sciences, 6 Makarova Emb., Saint Petersburg 199034, Russia.,Pavlov Institute of Physiology of the Russian Academy of Sciences, 6 Makarova Emb., Saint Petersburg 199034, Russia
| | - Vera B Plakhova
- Pavlov Institute of Physiology of the Russian Academy of Sciences, 6 Makarova Emb., Saint Petersburg 199034, Russia.,Pavlov Institute of Physiology of the Russian Academy of Sciences, 6 Makarova Emb., Saint Petersburg 199034, Russia
| | - Valentina A Penniyaynen
- Pavlov Institute of Physiology of the Russian Academy of Sciences, 6 Makarova Emb., Saint Petersburg 199034, Russia.,Pavlov Institute of Physiology of the Russian Academy of Sciences, 6 Makarova Emb., Saint Petersburg 199034, Russia
| | - Stanislav G Terekhin
- Pavlov Institute of Physiology of the Russian Academy of Sciences, 6 Makarova Emb., Saint Petersburg 199034, Russia.,Pavlov Institute of Physiology of the Russian Academy of Sciences, 6 Makarova Emb., Saint Petersburg 199034, Russia
| | - Svetlana A Podzorova
- Pavlov Institute of Physiology of the Russian Academy of Sciences, 6 Makarova Emb., Saint Petersburg 199034, Russia.,Pavlov Institute of Physiology of the Russian Academy of Sciences, 6 Makarova Emb., Saint Petersburg 199034, Russia
| | - Boris V Krylov
- Pavlov Institute of Physiology of the Russian Academy of Sciences, 6 Makarova Emb., Saint Petersburg 199034, Russia.,Pavlov Institute of Physiology of the Russian Academy of Sciences, 6 Makarova Emb., Saint Petersburg 199034, Russia
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5
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Keyster M, Niekerk LA, Basson G, Carelse M, Bakare O, Ludidi N, Klein A, Mekuto L, Gokul A. Decoding Heavy Metal Stress Signalling in Plants: Towards Improved Food Security and Safety. PLANTS (BASEL, SWITZERLAND) 2020; 9:E1781. [PMID: 33339160 PMCID: PMC7765602 DOI: 10.3390/plants9121781] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/20/2020] [Accepted: 11/30/2020] [Indexed: 12/12/2022]
Abstract
The mining of heavy metals from the environment leads to an increase in soil pollution, leading to the uptake of heavy metals into plant tissue. The build-up of toxic metals in plant cells often leads to cellular damage and senescence. Therefore, it is of utmost importance to produce plants with improved tolerance to heavy metals for food security, as well as to limit heavy metal uptake for improved food safety purposes. To achieve this goal, our understanding of the signaling mechanisms which regulate toxic heavy metal uptake and tolerance in plants requires extensive improvement. In this review, we summarize recent literature and data on heavy metal toxicity (oral reference doses) and the impact of the metals on food safety and food security. Furthermore, we discuss some of the key events (reception, transduction, and response) in the heavy metal signaling cascades in the cell wall, plasma membrane, and cytoplasm. Our future perspectives provide an outlook of the exciting advances that will shape the plant heavy metal signaling field in the near future.
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Affiliation(s)
- Marshall Keyster
- Environmental Biotechnology Laboratory, Department of Biotechnology, University of the Western Cape, Bellville 7535, South Africa; (L.-A.N.); (M.C.); (O.B.)
- DST-NRF Centre of Excellence in Food Security, University of the Western Cape, Bellville 7530, South Africa;
| | - Lee-Ann Niekerk
- Environmental Biotechnology Laboratory, Department of Biotechnology, University of the Western Cape, Bellville 7535, South Africa; (L.-A.N.); (M.C.); (O.B.)
| | - Gerhard Basson
- Plant Biotechnology Research Group, Department of Biotechnology, University of the Western Cape, Bellville 7535, South Africa;
| | - Mogamat Carelse
- Environmental Biotechnology Laboratory, Department of Biotechnology, University of the Western Cape, Bellville 7535, South Africa; (L.-A.N.); (M.C.); (O.B.)
| | - Olalekan Bakare
- Environmental Biotechnology Laboratory, Department of Biotechnology, University of the Western Cape, Bellville 7535, South Africa; (L.-A.N.); (M.C.); (O.B.)
| | - Ndiko Ludidi
- DST-NRF Centre of Excellence in Food Security, University of the Western Cape, Bellville 7530, South Africa;
- Plant Biotechnology Research Group, Department of Biotechnology, University of the Western Cape, Bellville 7535, South Africa;
| | - Ashwil Klein
- Plant Omics Laboratory, Department of Biotechnology, University of the Western Cape, Bellville 7535, South Africa;
| | - Lukhanyo Mekuto
- Department of Chemical Engineering, University of Johannesburg, Johannesburg 2028, South Africa;
| | - Arun Gokul
- Department of Chemical Engineering, University of Johannesburg, Johannesburg 2028, South Africa;
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6
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Huang XP, Kenakin TP, Gu S, Shoichet BK, Roth BL. Differential Roles of Extracellular Histidine Residues of GPR68 for Proton-Sensing and Allosteric Modulation by Divalent Metal Ions. Biochemistry 2020; 59:3594-3614. [PMID: 32865988 DOI: 10.1021/acs.biochem.0c00576] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
GPR68, an orphan G-protein coupled receptor, senses protons, couples to multiple G-proteins, and is also activated or inhibited by divalent metal ions. It has seven extracellular histidine residues, although it is not clear how these histidine residues play a role in both proton-sensing and metal ion modulation. Here we demonstrate that divalent metal ions are allosteric modulators that can activate or inhibit proton activity in a concentration- and pH-dependent manner. We then show that single histidine mutants have differential and varying degrees of effects on proton-sensing and metal ion modulation. Some histidine residues play dual roles in proton-sensing and metal ion modulation, while others are important in one or the other but not both. Two extracellular disulfide bonds are predicted to constrain histidine residues to be spatially close to each other. Combining histidine mutations leads to reduced proton activity and resistance to metal ion modulation, while breaking the less conserved disulfide bond results in a more severe reduction in proton-sensing over metal modulation. The small-molecule positive allosteric modulators (PAMs) ogerin and lorazepam are not affected by these mutations and remain active at mutants with severely reduced proton activity or are resistant to metal ion modulation. These results suggest GPR68 possesses two independent allosteric modulation systems, one through interaction with divalent metal ions at the extracellular surface and another through small-molecule PAMs in the transmembrane domains. A new GPR68 model is developed to accommodate the findings which could serve as a template for further studies and ligand discovery by virtual ligand docking.
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Affiliation(s)
| | | | - Shuo Gu
- Department of Pharmaceutical Science, University of California, San Francisco, California 94158, United States
| | - Brian K Shoichet
- Department of Pharmaceutical Science, University of California, San Francisco, California 94158, United States
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7
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Chan HC, Xu Y, Tan L, Vogel H, Cheng J, Wu D, Yuan S. Enhancing the Signaling of GPCRs via Orthosteric Ions. ACS CENTRAL SCIENCE 2020; 6:274-282. [PMID: 32123746 PMCID: PMC7047428 DOI: 10.1021/acscentsci.9b01247] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Indexed: 05/02/2023]
Abstract
G protein-coupled receptors play essential roles in cellular processes such as neuronal signaling, vision, olfaction, tasting, and metabolism. As GPCRs are the most important drug targets, understanding their interactions with ligands is of utmost importance for discovering related new medicines. In many GPCRs, an allosteric sodium ion next to the highly conserved residue D2.50 has been proposed to stabilize the inactive receptor state by mediating interactions between transmembrane helices. Here, we probed the existence of internal and functionally important sodium ions in the dopamine D2 receptor, using molecular dynamics simulations. Besides a new sodium ion at the allosteric ligand binding site, we discovered an additional sodium ion, located close to the orthosteric ligand binding site. Through cell-based activation assays, the signaling of D2 receptor with site-specific mutations was tested against a series of chemically modified agonists. We concluded an important structural role of this newly discovered orthosteric sodium ion in modulating the receptor signaling: It enables the coordination of a polar residue in the ligand binding site with an appropriately designed agonist molecule. An identical interaction was also observed in a recently released high-resolution crystal structure of mu-opioid receptor, which was reresolved in this work. Probably because of similar interactions, various metal ions have been found to increase the signaling of many other GPCRs. This unique principle and strategy could be used to optimize the drug activity of GPCR. Our findings open a new mechanistic opportunity of GPCR signaling and help design the next generation of drugs targeting GPCRs.
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Affiliation(s)
- H. C.
Stephen Chan
- Shenzhen
Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Yueming Xu
- iHuman
Institute, ShanghaiTech University, Shanghai 201210, China
| | - Liang Tan
- iHuman
Institute, ShanghaiTech University, Shanghai 201210, China
| | - Horst Vogel
- Shenzhen
Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
- Institute
of Chemical Sciences and Engineering, Ecole
Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Jianjun Cheng
- iHuman
Institute, ShanghaiTech University, Shanghai 201210, China
- E-mail:
| | - Dong Wu
- iHuman
Institute, ShanghaiTech University, Shanghai 201210, China
- E-mail:
| | - Shuguang Yuan
- Shenzhen
Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
- E-mail:
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8
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Abstract
Nanomedicine is a discipline that applies nanoscience and nanotechnology principles to the prevention, diagnosis, and treatment of human diseases. Self-assembly of molecular components is becoming a common strategy in the design and syntheses of nanomaterials for biomedical applications. In both natural and synthetic self-assembled nanostructures, molecular cooperativity is emerging as an important hallmark. In many cases, interplay of many types of noncovalent interactions leads to dynamic nanosystems with emergent properties where the whole is bigger than the sum of the parts. In this review, we provide a comprehensive analysis of the cooperativity principles in multiple self-assembled nanostructures. We discuss the molecular origin and quantitative modeling of cooperative behaviors. In selected systems, we describe the examples on how to leverage molecular cooperativity to design nanomedicine with improved diagnostic precision and therapeutic efficacy in medicine.
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Affiliation(s)
- Yang Li
- Department of Pharmacology, Simmons Comprehensive Cancer Center , UT Southwestern Medical Center , 5323 Harry Hines Boulevard , Dallas , Texas 75390 , United States
| | - Yiguang Wang
- Department of Pharmacology, Simmons Comprehensive Cancer Center , UT Southwestern Medical Center , 5323 Harry Hines Boulevard , Dallas , Texas 75390 , United States.,Beijing Key Laboratory of Molecular Pharmaceutics and State Key Laboratory of Natural and Biomimetic Drugs , Peking University , Beijing , 100191 , China
| | - Gang Huang
- Department of Pharmacology, Simmons Comprehensive Cancer Center , UT Southwestern Medical Center , 5323 Harry Hines Boulevard , Dallas , Texas 75390 , United States
| | - Jinming Gao
- Department of Pharmacology, Simmons Comprehensive Cancer Center , UT Southwestern Medical Center , 5323 Harry Hines Boulevard , Dallas , Texas 75390 , United States
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9
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Abe-Ohya R, Ishikawa T, Shiozawa H, Suda K, Nara F. Identification of metals from osteoblastic ST-2 cell supernatants as novel OGR1 agonists. J Recept Signal Transduct Res 2015; 35:485-92. [DOI: 10.3109/10799893.2015.1015736] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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10
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Feng T, Chen W, Li D, Lin H, Liu F, Bao Q, Lei Y, Zhang X, Xu X, Guo X, You Q, Sun H. Identification of novel JMJD2A inhibitor scaffold using shape and electrostatic similarity search combined with docking method and MM-GBSA approach. RSC Adv 2015. [DOI: 10.1039/c5ra11896d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We present a hierarchical workflow combining shape- and electrostatic-based virtual screening for the identification of novel Jumonji domain-containing protein 2A (JMJD2A) inhibitors.
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11
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Putula J, Pihlajamaa T, Kukkonen JP. Calcium affects OX1 orexin (hypocretin) receptor responses by modifying both orexin binding and the signal transduction machinery. Br J Pharmacol 2014; 171:5816-28. [PMID: 25132134 DOI: 10.1111/bph.12883] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 08/05/2014] [Accepted: 08/12/2014] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND AND PURPOSE One of the major responses upon orexin receptor activation is Ca(2+) influx, and this influx seems to amplify the other responses mediated by orexin receptors. However, the reduction in Ca(2+) , often used to assess the importance of Ca(2+) influx, might affect other properties, like ligand-receptor interactions, as suggested for some GPCR systems. Hence, we investigated the role of the ligand-receptor interaction and Ca(2+) signal cascades in the apparent Ca(2+) requirement of orexin-A signalling. EXPERIMENTAL APPROACH Receptor binding was assessed in CHO cells expressing human OX1 receptors with [(125) I]-orexin-A by conventional ligand binding as well as scintillation proximity assays. PLC activity was determined by chromatography. KEY RESULTS Both orexin receptor binding and PLC activation were strongly dependent on the extracellular Ca(2+) concentration. The relationship between Ca(2+) concentration and receptor binding was the same as that for PLC activation. However, when Ca(2+) entry was reduced by depolarizing the cells or by inhibiting the receptor-operated Ca(2+) channels, orexin-A-stimulated PLC activity was much more strongly inhibited than orexin-A binding. CONCLUSIONS AND IMPLICATIONS Ca(2+) plays a dual role in orexin signalling by being a prerequisite for both ligand-receptor interaction and amplifying orexin signals via Ca(2+) influx. Some previous results obtained utilizing Ca(2+) chelators have to be re-evaluated based on the results of the current study. From a drug discovery perspective, further experiments need to identify the target for Ca(2+) in orexin-A-OX1 receptor interaction and its mechanism of action.
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Affiliation(s)
- Jaana Putula
- Biochemistry and Cell Biology, Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
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12
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Yoon H, Dell EJ, Freyer JL, Campos LM, Jang WD. Polymeric supramolecular assemblies based on multivalent ionic interactions for biomedical applications. POLYMER 2014. [DOI: 10.1016/j.polymer.2013.12.038] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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13
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Wang H, Liu P, Xie H. An empirical molecular docking study of a di-iron binding protein with iron ions. ACTA ACUST UNITED AC 2013. [DOI: 10.1631/jzus.c1200072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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14
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Kotynia A, Czyżnikowska Ż, Cebrat M, Jaremko Ł, Gładysz O, Jaremko M, Marciniak A, Brasuń J. The role of hydroxyl group of tyrosine in copper(II) binding by His-analogs of oxytocin. Inorganica Chim Acta 2013. [DOI: 10.1016/j.ica.2012.09.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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15
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Chandrashekaran IR, Rao GS, Cowsik SM. Molecular modeling of the peptide agonist-binding site in a neurokinin-2 receptor. J Chem Inf Model 2009; 49:1734-40. [PMID: 19534508 DOI: 10.1021/ci900055x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The neurokinin-2 receptor is a member of the rhodopsin family of G-protein coupled receptors, which represents one of the most relevant target families in small-molecule drug design. NK-2 receptors have been implicated in playing a pathophysiological role in asthma. Activation of the NK-2 receptor by its endogenous peptide agonist, tachykinins, is associated with diverse biological responses like bronchoconstriction, vasodepression, and regulation of endocrine functions. Agonist binding to the receptor is a crucial event in initiating signaling, and therefore characterization of the structural features of the agonists can reveal the molecular basis of receptor activation and help in rational design of novel therapeutics. In this study a molecular model for the interaction of the primary ligand NKA with its G-protein coupled receptor neurokinin-2 receptor has been developed. A three-dimensional model for the NK-2 receptor has been generated by homology modeling using rhodopsin as a template. A knowledge based docking of the NMR derived bioactive conformation of NKA to the receptor has been performed utilizing the ligand binding data obtained from the photoaffinity labeling and site-directed mutagenesis studies. The molecular model for the NKA/NK-2 receptor complex thus obtained sheds light on the topographical features of the binding pocket of the receptor and provides atomic insight into the biochemical data currently available for the receptor. The results of the receptor modeling studies have been used to discuss the molecular determinants for NK-2 receptor selectivity.
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Chen D, Menche G, Power TD, Sower L, Peterson JW, Schein CH. Accounting for ligand-bound metal ions in docking small molecules on adenylyl cyclase toxins. Proteins 2007; 67:593-605. [PMID: 17311351 DOI: 10.1002/prot.21249] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The adenylyl cyclase toxins produced by bacteria (such as the edema factor (EF) of Bacillus anthracis and CyaA of Bordetella pertussis) are important virulence factors in anthrax and whooping cough. Co-crystal structures of these proteins differ in the number and positioning of metal ions in the active site. Metal ions bound only to the ligands in the crystal structures are not included during the docking. To determine what effect these "missing" metals have on docking results, the AutoDock, LigandFit/Cerius2, and FlexX programs were compared for their ability to correctly place substrate analogues and inhibitors into the active sites of the crystal structures of EF, CyaA, and mammalian adenylate cyclase. Protonating the phosphates of substrate analogues improved the accuracy of docking into the active site of CyaA, where the grid did not account for one of the three Mg2+ ions in the crystal structure. The AutoDock ranking (based on docking energies) of a test group of compounds was relatively unaffected by protonation of carboxyl groups. However, the ranking by FlexX-ChemScore varied significantly, especially for docking to CyaA, suggesting that alternate protonation states should be tested when screening compound libraries with this program. When the charges on the bound metal were set correctly, AutoDock was the most reliable program of the three tested with respect to positioning substrate analogues and ranking compounds according to their experimentally determined ability to inhibit EF.
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Affiliation(s)
- Deliang Chen
- Sealy Center for Structural Biology and Molecular Biophysics, Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas 77555-0857, USA
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