I03-Macromolecular Crystallography
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Wanwisa
Dejnirattisai
,
Jiandong
Huo
,
Daming
Zhou
,
Jiří
Zahradník
,
Piyada
Supasa
,
Chang
Liu
,
Helen M. E.
Duyvesteyn
,
Helen M.
Ginn
,
Alexander J.
Mentzer
,
Aekkachai
Tuekprakhon
,
Rungtiwa
Nutalai
,
Beibei
Wang
,
Aiste
Dijokaite
,
Suman
Khan
,
Ori
Avinoam
,
Mohammad
Bahar
,
Donal
Skelly
,
Sandra
Adele
,
Sile Ann
Johnson
,
Ali
Amini
,
Thomas
Ritter
,
Chris
Mason
,
Christina
Dold
,
Daniel
Pan
,
Sara
Assadi
,
Adam
Bellass
,
Nikki
Omo-Dare
,
David
Koeckerling
,
Amy
Flaxman
,
Daniel
Jenkin
,
Parvinder K.
Aley
,
Merryn
Voysey
,
Sue Ann
Costa Clemens
,
Felipe Gomes
Naveca
,
Valdinete
Nascimento
,
Fernanda
Nascimento
,
Cristiano
Fernandes Da Costa
,
Paola Cristina
Resende
,
Alex
Pauvolid-Correa
,
Marilda M.
Siqueira
,
Vicky
Baillie
,
Natali
Serafin
,
Gaurav
Kwatra
,
Kelly
Da Silva
,
Shabir A.
Madhi
,
Marta C.
Nunes
,
Tariq
Malik
,
Peter J. M.
Openshaw
,
J. Kenneth
Baillie
,
Malcolm G.
Semple
,
Alain R.
Townsend
,
Kuan-Ying A.
Huang
,
Tiong Kit
Tan
,
Miles W.
Carroll
,
Paul
Klenerman
,
Eleanor
Barnes
,
Susanna J.
Dunachie
,
Bede
Constantinides
,
Hermione
Webster
,
Derrick
Crook
,
Andrew J.
Pollard
,
Teresa
Lambe
,
Neil G.
Paterson
,
Mark A.
Williams
,
David R.
Hall
,
Elizabeth E.
Fry
,
Juthathip
Mongkolsapaya
,
Jingshan
Ren
,
Gideon
Schreiber
,
David I.
Stuart
,
Gavin R.
Screaton
Diamond Proposal Number(s):
[27009]
Abstract: On the 24th November 2021 the sequence of a new SARS CoV-2 viral isolate Omicron-B.1.1.529 was announced, containing far more mutations in Spike (S) than previously reported variants. Neutralization titres of Omicron by sera from vaccinees and convalescent subjects infected with early pandemic as well as Alpha, Beta, Gamma, Delta are substantially reduced or fail to neutralize. Titres against Omicron are boosted by third vaccine doses and are high in cases both vaccinated and infected by Delta. Mutations in Omicron knock out or substantially reduce neutralization by most of a large panel of potent monoclonal antibodies and antibodies under commercial development. Omicron S has structural changes from earlier viruses, combining mutations conferring tight binding to ACE2 to unleash evolution driven by immune escape, leading to a large number of mutations in the ACE2 binding site which rebalance receptor affinity to that of early pandemic viruses.
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Jan 2022
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Open Access
Abstract: Global vaccination programs using live-attenuated oral and inactivated polio vaccine (OPV and IPV) have almost eradicated poliovirus (PV) but these vaccines or their production pose significant risk in a polio-free world. Recombinant PV virus-like particles (VLPs), lacking the viral genome, represent safe next-generation vaccines, however their production requires optimisation. Here we present an efficient mammalian expression strategy producing good yields of wild-type PV VLPs for all three serotypes and a thermostabilised variant for PV3. Whilst the wild-type VLPs were predominantly in the non-native C-antigenic form, the thermostabilised PV3 VLPs adopted the native D-antigenic conformation eliciting neutralising antibody titres equivalent to the current IPV and were indistinguishable from natural empty particles by cryo-electron microscopy with a similar stabilising lipidic pocket-factor in the VP1 β-barrel. This factor may not be available in alternative expression systems, which may require synthetic pocket-binding factors. VLPs equivalent to these mammalian expressed thermostabilized particles, represent safer non-infectious vaccine candidates for the post-eradication era.
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Jan 2021
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Krios I-Titan Krios I at Diamond
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Open Access
Abstract: Poliovirus (PV) is the causative agent of poliomyelitis, a crippling human disease known since antiquity. PV occurs in two distinct antigenic forms, D and C, of which only the D form elicits a robust neutralizing response. Developing a synthetically produced stabilized virus-like particle (sVLP)-based vaccine with D antigenicity, without the drawbacks of current vaccines, will be a major step towards the final eradication of poliovirus. Such a sVLP would retain the native antigenic conformation and the repetitive structure of the original virus particle, but lack infectious genomic material. In this study, we report the production of synthetically stabilized PV VLPs in plants. Mice carrying the gene for the human PV receptor are protected from wild-type PV when immunized with the plant-made PV sVLPs. Structural analysis of the stabilized mutant at 3.6 Å resolution by cryo-electron microscopy and single-particle reconstruction reveals a structure almost indistinguishable from wild-type PV3.
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Aug 2017
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I04-1-Macromolecular Crystallography (fixed wavelength)
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Diamond Proposal Number(s):
[8423]
Abstract: Infectious pancreatic necrosis virus (IPNV), a member of the family Birnaviridae, infects young salmon, with a severe impact on the commercial sea farming industry. Of the five mature proteins encoded by the IPNV genome, the multifunctional VP3 has an essential role in morphogenesis; interacting with the capsid protein VP2, the viral double-stranded RNA (dsRNA) genome and the RNA-dependent RNA polymerase VP1. Here we investigate one of these VP3 functions and present the crystal structure of the C-terminal 12 residues of VP3 bound to the VP1 polymerase. This interaction, visualized for the first time, reveals the precise molecular determinants used by VP3 to bind the polymerase. Competition binding studies confirm that this region of VP3 is necessary and sufficient for VP1 binding, while biochemical experiments show that VP3 attachment has no effect on polymerase activity. These results indicate how VP3 recruits the polymerase into birnavirus capsids during morphogenesis.
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Feb 2013
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I03-Macromolecular Crystallography
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Open Access
Abstract: The morphogenesis of poxviruses such as vaccinia virus (VACV) sees the virion shape mature from spherical to brick-shaped. Trimeric capsomers of the VACV D13 protein form a transitory, stabilizing lattice on the surface of the initial spherical immature virus particle. The crystal structure of D13 reveals that this major scaffolding protein comprises a double β barrel “jelly-roll” subunit arranged as pseudo-hexagonal trimers. These structural features are characteristic of the major capsid proteins of a lineage of large icosahedral double-stranded DNA viruses including human adenovirus and the bacteriophages PRD1 and PM2. Structure-based phylogenetic analysis confirms that VACV belongs to this lineage, suggesting that (analogously to higher organism embryogenesis) early poxvirus morphogenesis reflects their evolution from a lineage of viruses sharing a common icosahedral ancestor.
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Dec 2011
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I02-Macromolecular Crystallography
I24-Microfocus Macromolecular Crystallography
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Open Access
Abstract: The RNA-dependent RNA polymerase VP1 of infectious pancreatic necrosis virus (IPNV) is a single polypeptide responsible for both viral RNA transcription and genome replication. Sequence analysis identifies IPNV VP1 as having an unusual active site topology. We have purified, crystallized and solved the structure of IPNV VP1 to 2.3 Å resolution in its apo form and at 2.2 Å resolution bound to the catalytically-activating metal magnesium. We find that recombinantly-expressed VP1 is highly active for RNA transcription and replication, yielding both free and polymerase-attached RNA products. IPNV VP1 also possesses terminal (deoxy)nucleotide transferase, RNA-dependent DNA polymerase (reverse transcriptase) and template-independent self-guanylylation activity. The N-terminus of VP1 interacts with the active-site cleft and we show that the N-terminal serine residue is required for formation of covalent RNA:polymerase complexes, providing a mechanism for the genesis of viral genome:polymerase complexes observed in vivo.
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Dec 2011
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I03-Macromolecular Crystallography
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Open Access
Abstract: Vaccinia virus (VACV) protein N1 is an intracellular virulence factor and belongs to a family of VACV B-cell lymphoma (Bcl)-2-like proteins whose members inhibit apoptosis or activation of pro-inflammatory transcription factors, such as interferon (IFN) regulatory factor-3 (IRF-3) and nuclear factor-κB (NF-κB). Unusually, N1 inhibits both apoptosis and NF-κB activation. To understand how N1 exerts these different functions, we have mutated residues in the Bcl-2-like surface groove and at the interface used to form N1 homodimers. Mutagenesis of the surface groove abolished only the N1 anti-apoptotic activity and protein crystallography showed these mutants differed from wild-type N1 only at the site of mutation. Conversely, mutagenesis of the dimer interface converted N1 to a monomer and affected only inhibition of NF-κB activation. Collectively, these data show that N1 inhibits pro-inflammatory and pro-apoptotic signalling using independent surfaces of the protein. To determine the relative contribution of each activity to virus virulence, mutant N1 alleles were introduced into a VACV strain lacking N1 and the virulence of these viruses was analysed after intradermal and intranasal inoculation in mice. In both models, VACV containing a mutant N1 unable to inhibit apoptosis had similar virulence to wild-type virus, whereas VACV containing a mutant N1 impaired for NF-κB inhibition induced an attenuated infection similar to that of the N1-deleted virus. This indicates that anti-apoptotic activity of N1 does not drive virulence in these in vivo models, and highlights the importance of pro-inflammatory signalling in the immune response against viral infections.
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Dec 2011
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Oct 2011
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Open Access
Abstract: Viruses are obligate intracellular parasites and are some of the most rapidly evolving and diverse pathogens encountered by the host immune system. Large complicated viruses, such as poxviruses, have evolved a plethora of proteins to disrupt host immune signalling, in their battle against immune surveillance. Recent X-ray crystallographic analysis of these viral immunomodulators has helped form an emerging picture of the molecular details of virus-host interactions. In this review we consider some of these immune evasion strategies as they apply to poxviruses, from a structural perspective, with specific examples from the European SPINE2-Complexes initiative. Structures of poxvirus immunomodulators reveal the capacity of viruses to mimic and compete against the host immune system, using a diverse range of structural folds that are unique or acquired from their hosts with both enhanced and unexpectedly divergent functions.
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Apr 2011
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Open Access
Abstract: The IκB kinase (IKK) complex regulates activation of nuclear factor kappa B (NF-κB), a critical transcription factor in mediating inflammatory and immune responses. Not surprisingly, therefore, many viruses seek to inhibit NF-κB activation. The vaccinia virus (VACV) B14 protein contributes to virus virulence by binding to the IKKβ subunit of the IKK complex and preventing NF-κB activation in response to pro-inflammatory stimuli. Previous crystallographic studies showed that the B14 protein has a Bcl-2-like fold and forms homo-dimers in the crystal. However, multi-angle light scattering indicated that B14 is in monomer:dimer equilibrium in solution. This transient self-association suggested that the hydrophobic dimerisation interface of B14 might also mediate its interaction with IKKβ and this was investigated by introducing amino acid substitutions on the dimer interface. One mutant (Y35E) was entirely monomeric but still co-immunoprecipitated with IKKβ and blocked both NF-κB nuclear translocation and NF-κB-dependent gene expression. Therefore, B14 homo-dimerisation is non-essential for binding and inhibition of IKKβ. In contrast, a second monomeric mutant (F130K) neither bound IKKβ nor inhibited NF-κB-dependent gene expression, demonstrating that this residue is required for the B14-IKKβ interaction. Thus the dimerisation and IKKβ-binding interfaces overlap and lie on a surface used for protein:protein interactions in many viral and cellular Bcl-2-like proteins.
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Apr 2011
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