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Nassar A, Ibrahim IM, Amin FG, Magdy M, Elgharib AM, Azzam EB, Nasser F, Yousry K, Shamkh IM, Mahdy SM, Elfiky AA. A Review of Human Coronaviruses' Receptors: The Host-Cell Targets for the Crown Bearing Viruses. Molecules 2021; 26:6455. [PMID: 34770863 PMCID: PMC8587140 DOI: 10.3390/molecules26216455] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 10/20/2021] [Accepted: 10/22/2021] [Indexed: 12/19/2022] Open
Abstract
A novel human coronavirus prompted considerable worry at the end of the year 2019. Now, it represents a significant global health and economic burden. The newly emerged coronavirus disease caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the primary reason for the COVID-19 global pandemic. According to recent global figures, COVID-19 has caused approximately 243.3 million illnesses and 4.9 million deaths. Several human cell receptors are involved in the virus identification of the host cells and entering them. Hence, understanding how the virus binds to host-cell receptors is crucial for developing antiviral treatments and vaccines. The current work aimed to determine the multiple host-cell receptors that bind with SARS-CoV-2 and other human coronaviruses for the purpose of cell entry. Extensive research is needed using neutralizing antibodies, natural chemicals, and therapeutic peptides to target those host-cell receptors in extremely susceptible individuals. More research is needed to map SARS-CoV-2 cell entry pathways in order to identify potential viral inhibitors.
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Affiliation(s)
- Aaya Nassar
- Biophysics Department, Faculty of Science, Cairo University, Giza 12511, Egypt; (I.M.I.); (F.G.A.); (M.M.); (A.M.E.)
| | - Ibrahim M. Ibrahim
- Biophysics Department, Faculty of Science, Cairo University, Giza 12511, Egypt; (I.M.I.); (F.G.A.); (M.M.); (A.M.E.)
| | - Fatma G. Amin
- Biophysics Department, Faculty of Science, Cairo University, Giza 12511, Egypt; (I.M.I.); (F.G.A.); (M.M.); (A.M.E.)
- Physics Department, Faculty of Science, Alexandria University, Alexandria 21519, Egypt
| | - Merna Magdy
- Biophysics Department, Faculty of Science, Cairo University, Giza 12511, Egypt; (I.M.I.); (F.G.A.); (M.M.); (A.M.E.)
| | - Ahmed M. Elgharib
- Biophysics Department, Faculty of Science, Cairo University, Giza 12511, Egypt; (I.M.I.); (F.G.A.); (M.M.); (A.M.E.)
| | - Eman B. Azzam
- Physics Department, Medical Biophysics Division, Faculty of Science, Helwan University, Cairo 11511, Egypt;
| | - Filopateer Nasser
- Biochemistry Department, Faculty of Science, Cairo University, Giza 12511, Egypt;
| | - Kirllos Yousry
- Faculty of Medicine, Cairo University, Cairo 11511, Egypt;
| | | | - Samah M. Mahdy
- National Museum of Egyptian Civilization, Ain Elsira-Elfustat, Cairo 11511, Egypt;
| | - Abdo A. Elfiky
- Biophysics Department, Faculty of Science, Cairo University, Giza 12511, Egypt; (I.M.I.); (F.G.A.); (M.M.); (A.M.E.)
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2
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Sutherland M, Kwon B, Hong M. Interactions of HIV gp41's membrane-proximal external region and transmembrane domain with phospholipid membranes from 31P NMR. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183723. [PMID: 34352242 DOI: 10.1016/j.bbamem.2021.183723] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 07/22/2021] [Accepted: 07/30/2021] [Indexed: 11/30/2022]
Abstract
HIV-1 entry into cells requires coordinated changes of the conformation and dynamics of both the fusion protein, gp41, and the lipids in the cell membrane and virus envelope. Commonly proposed features of membrane deformation during fusion include high membrane curvature, lipid disorder, and membrane surface dehydration. The virus envelope and target cell membrane contain a diverse set of phospholipids and cholesterol. To dissect how different lipids interact with gp41 to contribute to membrane fusion, here we use 31P solid-state NMR spectroscopy to investigate the curvature, dynamics, and hydration of POPE, POPC and POPS membranes, with and without cholesterol, in the presence of a peptide comprising the membrane proximal external region (MPER) and transmembrane domain (TMD) of gp41. Static 31P NMR spectra indicate that the MPER-TMD induces strong negative Gaussian curvature (NGC) to the POPE membrane but little curvature to POPC and POPC:POPS membranes. The NGC manifests as an isotropic peak in the static NMR spectra, whose intensity increases with the peptide concentration. Cholesterol inhibits the NGC formation and stabilizes the lamellar phase. Relative intensities of magic-angle spinning 31P cross-polarization and direct-polarization spectra indicate that all three phospholipids become more mobile upon peptide binding. Finally, 2D 1H-31P correlation spectra show that the MPER-TMD enhances water 1H polarization transfer to the lipids, indicating that the membrane surfaces become more hydrated. These results suggest that POPE is an essential component of the high-curvature fusion site, and lipid dynamic disorder is a general feature of membrane restructuring during fusion.
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Affiliation(s)
- Madeleine Sutherland
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Byungsu Kwon
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Mei Hong
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA.
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3
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Huang Y, Liu Y, Li Y, Liu Y, Zhang C, Wen H, Zhao L, Song Y, Wang L, Wang Z. Role of key amino acids in the transmembrane domain of the Newcastle disease virus fusion protein. Biosci Trends 2021; 15:16-23. [PMID: 33504738 DOI: 10.5582/bst.2020.03317] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Newcastle disease (ND), caused by the Newcastle disease virus (NDV), is transmitted by poultry with severe infectivity and a high fatality rate. The fusion (F) protein on the NDV envelope facilitates the merger of the viral and host cell membranes with the help of the homologous hemagglutinin-neuraminidase protein (HN). The transmembrane (TM) domains of viral fusion proteins are typically required for fusion, but the key amino acids in NDV F TM domains have not been identified. Site-directed mutagenesis was utilized to change the conserved amino acids at 500, 501, 502, 505, 510, 513, 516, 519, and 520 to alanine. It was found that mutants L519 and V520 had an interrupted protein expression, decreased to below 10%, and mutants A500, I505, V513, and V516 had a hypoactive impact on fusion activity, decreased to 85.38%, 67.05%, 55.38% and 51.13% of wt F, respectively. The results indicated that the TM domain plays a vital part in the fusion activity of the NDV F protein.
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Affiliation(s)
- Yanan Huang
- Department of Virology, School of Public Health, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Yaqing Liu
- Department of Virology, School of Public Health, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Yanguo Li
- Department of Health Management and Services, Cangzhou Medical College, Cangzhou, Hebei, China
| | - Ying Liu
- Department of Virology, School of Public Health, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Chi Zhang
- Department of Virology, School of Public Health, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Hongling Wen
- Department of Virology, School of Public Health, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Li Zhao
- Department of Virology, School of Public Health, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Yanyan Song
- Department of Virology, School of Public Health, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Liyang Wang
- Department of Clinical Laboratory, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Zhiyu Wang
- Department of Virology, School of Public Health, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
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4
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de la Arada I, Torralba J, Tascón I, Colom A, Ubarretxena-Belandia I, Arrondo JLR, Apellániz B, Nieva JL. Conformational plasticity underlies membrane fusion induced by an HIV sequence juxtaposed to the lipid envelope. Sci Rep 2021; 11:1278. [PMID: 33446748 PMCID: PMC7809034 DOI: 10.1038/s41598-020-80156-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 12/13/2020] [Indexed: 01/05/2023] Open
Abstract
Envelope glycoproteins from genetically-divergent virus families comprise fusion peptides (FPs) that have been posited to insert and perturb the membranes of target cells upon activation of the virus-cell fusion reaction. Conserved sequences rich in aromatic residues juxtaposed to the external leaflet of the virion-wrapping membranes are also frequently found in viral fusion glycoproteins. These membrane-proximal external regions (MPERs) have been implicated in the promotion of the viral membrane restructuring event required for fusion to proceed, hence, proposed to comprise supplementary FPs. However, it remains unknown whether the structure–function relationships governing canonical FPs also operate in the mirroring MPER sequences. Here, we combine infrared spectroscopy-based approaches with cryo-electron microscopy to analyze the alternating conformations adopted, and perturbations generated in membranes by CpreTM, a peptide derived from the MPER of the HIV-1 Env glycoprotein. Altogether, our structural and morphological data support a cholesterol-dependent conformational plasticity for this HIV-1 sequence, which could assist cell-virus fusion by destabilizing the viral membrane at the initial stages of the process.
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Affiliation(s)
- Igor de la Arada
- Instituto Biofisika (CSIC-UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
| | - Johana Torralba
- Instituto Biofisika (CSIC-UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain.,Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
| | - Igor Tascón
- Instituto Biofisika (CSIC-UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain.,Ikerbasque, Basque Foundation for Science, 48013, Bilbao, Spain
| | - Adai Colom
- Instituto Biofisika (CSIC-UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain.,Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain.,Ikerbasque, Basque Foundation for Science, 48013, Bilbao, Spain
| | - Iban Ubarretxena-Belandia
- Instituto Biofisika (CSIC-UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain.,Ikerbasque, Basque Foundation for Science, 48013, Bilbao, Spain
| | - José L R Arrondo
- Instituto Biofisika (CSIC-UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain.,Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
| | - Beatriz Apellániz
- Department of Physiology, Faculty of Pharmacy, University of the Basque Country (UPV/EHU), Paseo de la Universidad, 7, 01006, Vitoria-Gasteiz, Spain
| | - José L Nieva
- Instituto Biofisika (CSIC-UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain. .,Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain.
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5
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Zhao X, Tian JJ, Yu H, Bryksa BC, Dupuis JH, Ou X, Qian Z, Song C, Wang S, Yada RY. Insights into the mechanism of membrane fusion induced by the plant defense element, plant-specific insert. J Biol Chem 2020; 295:14548-14562. [PMID: 32651232 DOI: 10.1074/jbc.ra120.014311] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 07/01/2020] [Indexed: 11/06/2022] Open
Abstract
In plants, many natural defense mechanisms include cellular membrane fusion as a way to resist infection by external pathogens. Several plant proteins mediate membrane fusion, but the detailed mechanism by which they promote fusion is less clear. Understanding this process could provide valuable insights into these proteins' physiological functions and guide bioengineering applications (i.e. the design of antimicrobial proteins). The plant-specific insert (PSI) from Solanum tuberosum can help reduce certain pathogen attack via membrane fusion. To gain new insights into the process of PSI-induced membrane fusion, a combined approach of NMR, FRET, and in silico studies was used. Our results indicate that (i) under acidic conditions, the PSI experiences a monomer-dimer equilibrium, and the dimeric PSI induces membrane fusion below a certain critical pH; (ii) after fusion, the PSI resides in a highly dehydrated environment with limited solvent accessibility, suggesting its capability in reducing repulsive dehydration forces between liposomes to facilitate fusion; and (iii) as shown by molecular dynamics simulations, the PSI dimer can bind stably to membrane surfaces and can bridge liposomes in close proximity, a critical step for the membrane fusion. In summary, this study provides new and unique insights into the mechanisms by which the PSI and similar proteins induce membrane fusion.
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Affiliation(s)
- Xiaoli Zhao
- College of Chemistry and Molecular Engineering and Beijing NMR Center, Peking University, Beijing, China
| | - Jenny Jingxin Tian
- Food, Nutrition, and Health Program, Faculty of Land and Food Systems, University of British Columbia, Vancouver, British Columbia, Canada
| | - Hua Yu
- Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China; Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Brian C Bryksa
- Food, Nutrition, and Health Program, Faculty of Land and Food Systems, University of British Columbia, Vancouver, British Columbia, Canada
| | - John H Dupuis
- Food, Nutrition, and Health Program, Faculty of Land and Food Systems, University of British Columbia, Vancouver, British Columbia, Canada
| | - Xiuyuan Ou
- MOH Key Laboratory, Institute of Pathogen Biology, Chinese Academy of Medical Science, Beijing, China
| | - Zhaohui Qian
- MOH Key Laboratory, Institute of Pathogen Biology, Chinese Academy of Medical Science, Beijing, China
| | - Chen Song
- Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China; Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China.
| | - Shenlin Wang
- College of Chemistry and Molecular Engineering and Beijing NMR Center, Peking University, Beijing, China; Beijing National Laboratory for Molecular Sciences, Beijing, China.
| | - Rickey Y Yada
- Food, Nutrition, and Health Program, Faculty of Land and Food Systems, University of British Columbia, Vancouver, British Columbia, Canada.
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6
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Barrett CT, Dutch RE. Viral Membrane Fusion and the Transmembrane Domain. Viruses 2020; 12:v12070693. [PMID: 32604992 PMCID: PMC7412173 DOI: 10.3390/v12070693] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 06/24/2020] [Accepted: 06/25/2020] [Indexed: 01/05/2023] Open
Abstract
Initiation of host cell infection by an enveloped virus requires a viral-to-host cell membrane fusion event. This event is mediated by at least one viral transmembrane glycoprotein, termed the fusion protein, which is a key therapeutic target. Viral fusion proteins have been studied for decades, and numerous critical insights into their function have been elucidated. However, the transmembrane region remains one of the most poorly understood facets of these proteins. In the past ten years, the field has made significant advances in understanding the role of the membrane-spanning region of viral fusion proteins. We summarize developments made in the past decade that have contributed to the understanding of the transmembrane region of viral fusion proteins, highlighting not only their critical role in the membrane fusion process, but further demonstrating their involvement in several aspects of the viral lifecycle.
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7
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Liao SY, Lee M, Hong M. Interplay between membrane curvature and protein conformational equilibrium investigated by solid-state NMR. J Struct Biol 2019; 206:20-28. [PMID: 29501472 PMCID: PMC6119545 DOI: 10.1016/j.jsb.2018.02.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 02/19/2018] [Accepted: 02/26/2018] [Indexed: 11/28/2022]
Abstract
Many membrane proteins sense and induce membrane curvature for function, but structural information about how proteins modulate their structures to cause membrane curvature is sparse. We review our recent solid-state NMR studies of two virus membrane proteins whose conformational equilibrium is tightly coupled to membrane curvature. The influenza M2 proton channel has a drug-binding site in the transmembrane (TM) pore. Previous chemical shift data indicated that this pore-binding site is lost in an M2 construct that contains the TM domain and a curvature-inducing amphipathic helix. We have now obtained chemical shift perturbation, protein-drug proximity, and drug orientation data that indicate that the pore-binding site is restored when the full cytoplasmic domain is present. This finding indicates that the curvature-inducing amphipathic helix distorts the TM structure to interfere with drug binding, while the cytoplasmic tail attenuates this effect. In the second example, we review our studies of a parainfluenza virus fusion protein that merges the cell membrane and the virus envelope during virus entry. Chemical shifts of two hydrophobic domains of the protein indicate that both domains have membrane-dependent backbone conformations, with the β-strand structure dominating in negative-curvature phosphatidylethanolamine (PE) membranes. 31P NMR spectra and 1H-31P correlation spectra indicate that the β-strand-rich conformation induces saddle-splay curvature to PE membranes and dehydrates them, thus stabilizing the hemifusion state. These results highlight the indispensable role of solid-state NMR to simultaneously determine membrane protein structures and characterize the membrane curvature in which these protein structures exist.
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Affiliation(s)
- Shu Y Liao
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Myungwoon Lee
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Mei Hong
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, United States.
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8
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Li M, Mandal A, Tyurin VA, DeLucia M, Ahn J, Kagan VE, van der Wel PCA. Surface-Binding to Cardiolipin Nanodomains Triggers Cytochrome c Pro-apoptotic Peroxidase Activity via Localized Dynamics. Structure 2019; 27:806-815.e4. [PMID: 30879887 DOI: 10.1016/j.str.2019.02.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 01/16/2019] [Accepted: 02/15/2019] [Indexed: 02/06/2023]
Abstract
The peroxidation of cardiolipins by reactive oxygen species, which is regulated and enhanced by cytochrome c (cyt c), is a critical signaling event in mitochondrial apoptosis. We probe the molecular underpinnings of this mitochondrial death signal through structural and functional studies of horse heart cyt c binding to mixed-lipid membranes containing cardiolipin with mono- and polyunsaturated acyl chains. Lipidomics reveal the selective oxidation of polyunsaturated fatty acid (PUFA) cardiolipin (CL), while multidimensional solid-state NMR probes the structure and dynamics of the membrane and the peripherally bound protein. The hydrophilic milieu at the membrane interface stabilizes a native-like fold, but also leads to localized flexibility at the membrane-interacting protein face. PUFA CL acts as both a preferred substrate and a dynamic regulator by affecting the dynamics of the cyt c N70-I85 Ω loop, which covers the heme cavity.
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Affiliation(s)
- Mingyue Li
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Abhishek Mandal
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Vladimir A Tyurin
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Maria DeLucia
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Jinwoo Ahn
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Valerian E Kagan
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA 15213, USA; Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15213, USA; Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA; Department of Radiation Oncology, University of Pittsburgh, Pittsburgh, PA 15213, USA; Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA 15213, USA; Laboratory of Navigational Redox Lipidomics, IM Sechenov Moscow State Medical University, Moscow 119146, Russian Federation
| | - Patrick C A van der Wel
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA; Zernike Institute for Advanced Materials, University of Groningen, 9747 AG Groningen, The Netherlands.
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9
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Yan L, Meng B, Xiang J, Wilson IA, Yang B. Crystal structure of the post-fusion core of the Human coronavirus 229E spike protein at 1.86 Å resolution. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2018; 74:841-851. [PMID: 30198895 PMCID: PMC6130466 DOI: 10.1107/s2059798318008318] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Accepted: 06/05/2018] [Indexed: 01/12/2023]
Abstract
Human coronavirus 229E (HCoV‐229E) usually causes mild upper respiratory infections in heathy adults, but may lead to severe complications or mortality in individuals with weakened immune systems. Virus entry of HCoV‐229E is mediated by its spike (S) protein, where the S1 domain facilitates attachment to host cells and the S2 domain is involved in subsequent fusion of the virus and host membranes. During the fusion process, two heptad repeats, HR1 and HR2, in the S2 domain assemble into a six‐helix membrane‐fusion structure termed the fusion core. Here, the complete fusion‐core structure of HCoV‐229E has been determined at 1.86 Å resolution, representing the most complete post‐fusion conformation thus far among published human alphacoronavirus (α‐HCoV) fusion‐core structures. The overall structure of the HCoV‐229E fusion core is similar to those of SARS, MERS and HCoV‐NL63, but the packing of its 3HR1 core differs from those of SARS and MERS in that it contains more noncanonical `x' and `da' layers. Side‐by‐side electrostatic surface comparisons reveal that the electrostatic surface potentials are opposite in α‐HCoVs and β‐HCoVs at certain positions and that the HCoV‐229E surface also appears to be the most hydrophobic among the various HCoVs. In addition to the highly conserved hydrophobic interactions between HR1 and HR2, some polar and electrostatic interactions are also well preserved across different HCoVs. This study adds to the structural profiling of HCoVs to aid in the structure‐based design of pan‐coronavirus small molecules or peptides to inhibit viral fusion.
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Affiliation(s)
- Lei Yan
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai 201210, People's Republic of China
| | - Bing Meng
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai 201210, People's Republic of China
| | - Jiangchao Xiang
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai 201210, People's Republic of China
| | - Ian A Wilson
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai 201210, People's Republic of China
| | - Bei Yang
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai 201210, People's Republic of China
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10
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Falanga A, Galdiero M, Morelli G, Galdiero S. Membranotropic peptides mediating viral entry. Pept Sci (Hoboken) 2018; 110:e24040. [PMID: 32328541 PMCID: PMC7167733 DOI: 10.1002/pep2.24040] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 11/27/2017] [Accepted: 12/20/2017] [Indexed: 02/06/2023]
Abstract
The means used by enveloped viruses to bypass cellular membranes are well characterized; however, the mechanisms used by non-enveloped viruses to deliver their genome inside the cell remain unresolved and poorly defined. The discovery of short, membrane interacting, amphipathic or hydrophobic sequences (known as membranotropic peptides) in both enveloped and non-enveloped viruses suggests that these small peptides are strongly involved in breaching the host membrane and in the delivery of the viral genome into the host cell. Thus, in spite of noticeable differences in entry, this short stretches of membranotropic peptides are probably associated with similar entry-related events. This review will uncover the intrinsic features of viral membranotropic peptides involved in viral entry of both naked viruses and the ones encircled with a biological membrane with the objective to better elucidate their different functional properties and possible applications in the biomedical field.
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Affiliation(s)
- Annarita Falanga
- Department of Pharmacy, School of MedicineNaples80134Italy
- CIRPEB University of Naples Federico II, Via Mezzocannone 16Naples80134Italy
| | - Massimiliano Galdiero
- CIRPEB University of Naples Federico II, Via Mezzocannone 16Naples80134Italy
- Department of Experimental MedicineUniversity of Campania “Luigi Vanvitelli,” Via de CrecchioNaples80134Italy
| | - Giancarlo Morelli
- Department of Pharmacy, School of MedicineNaples80134Italy
- CIRPEB University of Naples Federico II, Via Mezzocannone 16Naples80134Italy
| | - Stefania Galdiero
- Department of Pharmacy, School of MedicineNaples80134Italy
- CIRPEB University of Naples Federico II, Via Mezzocannone 16Naples80134Italy
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11
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Kwon B, Lee M, Waring AJ, Hong M. Oligomeric Structure and Three-Dimensional Fold of the HIV gp41 Membrane-Proximal External Region and Transmembrane Domain in Phospholipid Bilayers. J Am Chem Soc 2018; 140:8246-8259. [PMID: 29888593 DOI: 10.1021/jacs.8b04010] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The HIV-1 glycoprotein, gp41, mediates fusion of the virus lipid envelope with the target cell membrane during virus entry into cells. Despite extensive studies of this protein, inconsistent and contradictory structural information abounds in the literature about the C-terminal membrane-interacting region of gp41. This C-terminal region contains the membrane-proximal external region (MPER), which harbors the epitopes for four broadly neutralizing antibodies, and the transmembrane domain (TMD), which anchors the protein to the virus lipid envelope. Due to the difficulty of crystallizing and solubilizing the MPER-TMD, most structural studies of this functionally important domain were carried out using truncated peptides either in the absence of membrane-mimetic solvents or bound to detergents and lipid bicelles. To determine the structural architecture of the MPER-TMD in the native environment of lipid membranes, we have now carried out a solid-state NMR study of the full MPER-TMD segment bound to cholesterol-containing phospholipid bilayers. 13C chemical shifts indicate that the majority of the peptide is α-helical, except for the C-terminus of the TMD, which has moderate β-sheet character. Intermolecular 19F-19F distance measurements of singly fluorinated peptides indicate that the MPER-TMD is trimerized in the virus-envelope mimetic lipid membrane. Intramolecular 13C-19F distance measurements indicate the presence of a turn between the MPER helix and the TMD helix. This is supported by lipid-peptide and water-peptide 2D 1H-13C correlation spectra, which indicate that the MPER binds to the membrane surface whereas the TMD spans the bilayer. Together, these data indicate that full-length MPER-TMD assembles into a trimeric helix-turn-helix structure in lipid membranes. We propose that the turn between the MPER and TMD may be important for inducing membrane defects in concert with negative-curvature lipid components such as cholesterol and phosphatidylethanolamine, while the surface-bound MPER helix may interact with N-terminal segments of the protein during late stages of membrane fusion.
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Affiliation(s)
- Byungsu Kwon
- Department of Chemistry , Massachusetts Institute of Technology , 170 Albany Street , Cambridge , Massachusetts 02139 , United States
| | - Myungwoon Lee
- Department of Chemistry , Massachusetts Institute of Technology , 170 Albany Street , Cambridge , Massachusetts 02139 , United States
| | - Alan J Waring
- Department of Medicine , Harbor-UCLA Medical Center , 1000 West Carson Street, Building RB2 , Torrance , California 90502 , United States
| | - Mei Hong
- Department of Chemistry , Massachusetts Institute of Technology , 170 Albany Street , Cambridge , Massachusetts 02139 , United States
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Abstract
Solid-state nuclear magnetic resonance (SSNMR) spectroscopy elucidates membrane protein structures and dynamics in atomic detail to yield mechanistic insights. By interrogating membrane proteins in phospholipid bilayers that closely resemble biological membranes, SSNMR spectroscopists have revealed ion conduction mechanisms, substrate transport dynamics, and oligomeric interfaces of seven-transmembrane helix proteins. Research has also identified conformational plasticity underlying virus-cell membrane fusions by complex protein machineries, and β-sheet folding and assembly by amyloidogenic proteins bound to lipid membranes. These studies collectively show that membrane proteins exhibit extensive structural plasticity to carry out their functions. Because of the inherent dependence of NMR frequencies on molecular orientations and the sensitivity of NMR frequencies to dynamical processes on timescales from nanoseconds to seconds, SSNMR spectroscopy is ideally suited to elucidate such structural plasticity, local and global conformational dynamics, protein-lipid and protein-ligand interactions, and protonation states of polar residues. New sensitivity-enhancement techniques, resolution enhancement by ultrahigh magnetic fields, and the advent of 3D and 4D correlation NMR techniques are increasingly aiding these mechanistically important structural studies.
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Affiliation(s)
- Venkata S Mandala
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA;
| | - Jonathan K Williams
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA;
| | - Mei Hong
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA;
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