I03-Macromolecular Crystallography
I23-Long wavelength MX
I24-Microfocus Macromolecular Crystallography
Krios II-Titan Krios II at Diamond
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Audrey
Le Bas
,
Bradley R.
Clarke
,
Tanisha
Teelucksingh
,
Micah
Lee
,
Kamel
El Omari
,
Andrew M.
Giltrap
,
Stephen A.
Mcmahon
,
Hui
Liu
,
John H.
Beale
,
Vitaliy
Mykhaylyk
,
Ramona
Duman
,
Neil G.
Paterson
,
Philip N.
Ward
,
Peter J.
Harrison
,
Miriam
Weckener
,
Els
Pardon
,
Jan
Steyaert
,
Huanting
Liu
,
Andrew
Quigley
,
Benjamin G.
Davis
,
Armin
Wagner
,
Chris
Whitfield
,
James H.
Naismith
Diamond Proposal Number(s):
[33941]
Open Access
Abstract: The enterobacterial common antigen (ECA) is conserved in Gram-negative bacteria of the Enterobacterales order although its function is debated. ECA biogenesis depends on the Wzx/Wzy-dependent strategy whereby the newly synthesized lipid-linked repeat units, lipid III, are transferred across the inner membrane by the lipid III flippase WzxE. WzxE is part of the Wzx family and required in many glycan assembly systems, but an understanding of its molecular mechanism is hindered due to a lack of structural evidence. Here, we present the first X-ray structures of WzxE from Escherichia coli in complex with nanobodies. Both inward- and outward-facing conformations highlight two pairs of arginine residues that move in a reciprocal fashion, enabling flipping. One of the arginine pairs coordinated to a glutamate residue is essential for activity along with the C-terminal arginine rich tail located close to the entrance of the lumen. This work helps understand the translocation mechanism of the Wzx flippase family.
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Jan 2025
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I03-Macromolecular Crystallography
I04-Macromolecular Crystallography
I24-Microfocus Macromolecular Crystallography
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Katy
Cornish
,
Jiandong
Huo
,
Luke
Jones
,
Parul
Sharma
,
Joseph W.
Thrush
,
Sahar
Abdelkarim
,
Anja
Kipar
,
Siva
Ramadurai
,
Miriam
Weckener
,
Halina
Mikolajek
,
Sai
Liu
,
Imogen
Buckle
,
Eleanor
Bentley
,
Adam
Kirby
,
Ximeng
Han
,
Stephen M.
Laidlaw
,
Michelle
Hill
,
Lauren
Eyssen
,
Chelsea
Norman
,
Audrey
Le Bas
,
John
Clarke
,
William
James
,
James P.
Stewart
,
Miles
Carroll
,
James
Naismith
,
Raymond J.
Owens
Diamond Proposal Number(s):
[27031]
Open Access
Abstract: The Omicron strains of SARS-CoV-2 pose a significant challenge to the development of effective antibody-based treatments as immune evasion has compromised most available immune therapeutics. Therefore, in the ‘arms race’ with the virus, there is a continuing need to identify new biologics for the prevention or treatment of SARS-CoV-2 infections. Here, we report the isolation of nanobodies that bind to the Omicron BA.1 spike protein by screening nanobody phage display libraries previously generated from llamas immunized with either the Wuhan or Beta spike proteins. The structure and binding properties of three of these nanobodies (A8, H6 and B5-5) have been characterized in detail providing insight into their binding epitopes on the Omicron spike protein. Trimeric versions of H6 and B5-5 neutralized the SARS-CoV-2 variant of concern BA.5 both in vitro and in the hamster model of COVID-19 following nasal administration. Thus, either alone or in combination could serve as starting points for the development of new anti-viral immunotherapeutics.
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Jun 2024
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Krios I-Titan Krios I at Diamond
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Gaia
Pasqualetto
,
Andrew
Mack
,
Emily
Lewis
,
Ryan
Cooper
,
Alistair
Holland
,
Ufuk
Borucu
,
Judith
Mantell
,
Tom
Davies
,
Miriam
Weckener
,
Dan
Clare
,
Tom
Green
,
Pete
Kille
,
Alex
Muhlhozl
,
Mark T.
Young
Diamond Proposal Number(s):
[26296]
Open Access
Abstract: Hemocyanins are multimeric oxygen transport proteins present in the blood of arthropods and molluscs, containing up to 8 oxygen-binding functional units per monomer. In molluscs, hemocyanins are assembled in decamer ‘building blocks’ formed of 5 dimer ‘plates’, routinely forming didecamer or higher-order assemblies with d5 or c5 symmetry. Here we describe the cryoEM structures of the didecamer (20-mer) and tridecamer (30-mer) forms of a novel hemocyanin from the slipper limpet Crepidula fornicata (SLH) at 7.0 and 4.7 Å resolution respectively. We show that two decamers assemble in a ‘tail-tail’ configuration, forming a partially capped cylinder, with an additional decamer adding on in ‘head-tail’ configuration to make the tridecamer. Analysis of SLH samples shows substantial heterogeneity, suggesting the presence of many higher-order multimers including tetra- and pentadecamers, formed by successive addition of decamers in head-tail configuration. Retrieval of sequence data for a full-length isoform of SLH enabled the use of Alphafold to produce a molecular model of SLH, which indicated the formation of dimer slabs with high similarity to those found in keyhole limpet hemocyanin. The fit of the molecular model to the cryoEM density was excellent, showing an overall structure where the final two functional units of the subunit (FU-g and FU-h) form the partial cap at one end of the decamer, and permitting analysis of the subunit interfaces governing the assembly of tail-tail and head-tail decamer interactions as well as potential sites for N-glycosylation. Our work contributes to the understanding of higher-order oligomer formation in molluscan hemocyanins and demonstrates the utility of Alphafold for building accurate structural models of large oligomeric proteins.
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Jun 2023
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Krios I-Titan Krios I at Diamond
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Diamond Proposal Number(s):
[16637]
Open Access
Abstract: The enterobacterial common antigen (ECA) is a carbohydrate polymer that is associated with the cell envelope in the Enterobacteriaceae. ECA contains a repeating trisaccharide which is polymerized by WzyE, a member of the Wzy membrane protein polymerase superfamily. WzyE activity is regulated by a membrane protein polysaccharide co-polymerase, WzzE. Förster resonance energy transfer experiments demonstrate that WzyE and WzzE from Pectobacterium atrosepticum form a complex in vivo, and immunoblotting and cryo-electron microscopy (cryo-EM) analysis confirm a defined stoichiometry of approximately eight WzzE to one WzyE. Low-resolution cryo-EM reconstructions of the complex, aided by an antibody recognizing the C-terminus of WzyE, reveals WzyE sits in the central membrane lumen formed by the octameric arrangement of the transmembrane helices of WzzE. The pairing of Wzy and Wzz is found in polymerization systems for other bacterial polymers, including lipopolysaccharide O-antigens and capsular polysaccharides. The data provide new structural insight into a conserved mechanism for regulating polysaccharide chain length in bacteria.
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Mar 2023
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I03-Macromolecular Crystallography
Krios II-Titan Krios II at Diamond
Krios IV-Titan Krios IV at Diamond
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Halina
Mikolajek
,
Miriam
Weckener
,
Z. Faidon
Brotzakis
,
Jiandong
Huo
,
Evmorfia V.
Dalietou
,
Audrey
Le Bas
,
Pietro
Sormanni
,
Peter J.
Harrison
,
Philip N.
Ward
,
Steven
Truong
,
Lucile
Moynie
,
Daniel K.
Clare
,
Maud
Dumoux
,
Joshua
Dormon
,
Chelsea
Norman
,
Naveed
Hussain
,
Vinod
Vogirala
,
Raymond J.
Owens
,
Michele
Vendruscolo
,
James
Naismith
Diamond Proposal Number(s):
[27031, 27051, 29666]
Open Access
Abstract: Camelid single-domain antibodies, also known as nanobodies, can be readily isolated from naïve libraries for specific targets but often bind too weakly to their targets to be immediately useful. Laboratory-based genetic engineering methods to enhance their affinity, termed maturation, can deliver useful reagents for different areas of biology and potentially medicine. Using the receptor binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein and a naïve library, we generated closely related nanobodies with micromolar to nanomolar binding affinities. By analyzing the structure–activity relationship using X-ray crystallography, cryoelectron microscopy, and biophysical methods, we observed that higher conformational entropy losses in the formation of the spike protein–nanobody complex are associated with tighter binding. To investigate this, we generated structural ensembles of the different complexes from electron microscopy maps and correlated the conformational fluctuations with binding affinity. This insight guided the engineering of a nanobody with improved affinity for the spike protein.
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Jul 2022
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Open Access
Abstract: The specimen preparation process is a key determinant in the success of any cryo electron microscopy (cryoEM) structural study and until recently had remained largely unchanged from the initial designs of Jacques Dubochet and others in the 1980s. The process has transformed structural biology, but it is largely manual and can require extensive optimisation for each protein sample. The chameleon instrument with its self-wicking grids and fast-plunge freezing represents a shift towards a robust, automated, and highly controllable future for specimen preparation. However, these new technologies require new workflows and an understanding of their limitations and strengths. As early adopters of the chameleon technology, we report on our experiences and lessons learned through case studies. We use these to make recommendations for the benefit of future users of the chameleon system and the field of cryoEM specimen preparation generally.
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Jun 2022
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I03-Macromolecular Crystallography
I04-Macromolecular Crystallography
I24-Microfocus Macromolecular Crystallography
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Jiandong
Huo
,
Halina
Mikolajek
,
Audrey
Le Bas
,
Jordan J.
Clark
,
Parul
Sharma
,
Anja
Kipar
,
Joshua
Dormon
,
Chelsea
Norman
,
Miriam
Weckener
,
Daniel K.
Clare
,
Peter J.
Harrison
,
Julia A.
Tree
,
Karen R.
Buttigieg
,
Francisco J.
Salguero
,
Robert
Watson
,
Daniel
Knott
,
Oliver
Carnell
,
Didier
Ngabo
,
Michael J.
Elmore
,
Susan
Fotheringham
,
Adam
Harding
,
Lucile
Moynie
,
Philip N.
Ward
,
Maud
Dumoux
,
Tessa
Prince
,
Yper
Hall
,
Julian A.
Hiscox
,
Andrew
Owen
,
William
James
,
Miles W.
Carroll
,
James P.
Stewart
,
James
Naismith
,
Raymond
Owens
Diamond Proposal Number(s):
[27031]
Open Access
Abstract: SARS-CoV-2 remains a global threat to human health particularly as escape mutants emerge. There is an unmet need for effective treatments against COVID-19 for which neutralizing single domain antibodies (nanobodies) have significant potential. Their small size and stability mean that nanobodies are compatible with respiratory administration. We report four nanobodies (C5, H3, C1, F2) engineered as homotrimers with pmolar affinity for the receptor binding domain (RBD) of the SARS-CoV-2 spike protein. Crystal structures show C5 and H3 overlap the ACE2 epitope, whilst C1 and F2 bind to a different epitope. Cryo Electron Microscopy shows C5 binding results in an all down arrangement of the Spike protein. C1, H3 and C5 all neutralize the Victoria strain, and the highly transmissible Alpha (B.1.1.7 first identified in Kent, UK) strain and C1 also neutralizes the Beta (B.1.35, first identified in South Africa). Administration of C5-trimer via the respiratory route showed potent therapeutic efficacy in the Syrian hamster model of COVID-19 and separately, effective prophylaxis. The molecule was similarly potent by intraperitoneal injection.
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Sep 2021
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B21-High Throughput SAXS
I03-Macromolecular Crystallography
I24-Microfocus Macromolecular Crystallography
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Tomasz
Uchański
,
Simonas
Masiulis
,
Baptiste
Fischer
,
Valentina
Kalichuk
,
Uriel
López-Sánchez
,
Eleftherios
Zarkadas
,
Miriam
Weckener
,
Andrija
Sente
,
Philip
Ward
,
Alexandre
Wohlkonig
,
Thomas
Zogg
,
Han
Remaut
,
James
Naismith
,
Hugues
Nury
,
Wim
Vranken
,
A. Radu
Aricescu
,
Els
Pardon
,
Jan
Steyaert
Abstract: Nanobodies are popular and versatile tools for structural biology. They have a compact single immunoglobulin domain organization, bind target proteins with high affinities while reducing their conformational heterogeneity and stabilize multi-protein complexes. Here we demonstrate that engineered nanobodies can also help overcome two major obstacles that limit the resolution of single-particle cryo-electron microscopy reconstructions: particle size and preferential orientation at the water–air interfaces. We have developed and characterized constructs, termed megabodies, by grafting nanobodies onto selected protein scaffolds to increase their molecular weight while retaining the full antigen-binding specificity and affinity. We show that the megabody design principles are applicable to different scaffold proteins and recognition domains of compatible geometries and are amenable for efficient selection from yeast display libraries. Moreover, we demonstrate that megabodies can be used to obtain three-dimensional reconstructions for membrane proteins that suffer from severe preferential orientation or are otherwise too small to allow accurate particle alignment.
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Jan 2021
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I03-Macromolecular Crystallography
Krios I-Titan Krios I at Diamond
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Jiangdong
Huo
,
Audrey
Le Bas
,
Reinis R.
Ruza
,
Helen M. E.
Duyvesteyn
,
Halina
Mikolajek
,
Tomas
Malinauskas
,
Tiong Kit
Tan
,
Pramila
Rijal
,
Maud
Dumoux
,
Philip N.
Ward
,
Jingshan
Ren
,
Daming
Zhou
,
Peter J.
Harrison
,
Miriam
Weckener
,
Daniel K.
Clare
,
Vinod K.
Vogirala
,
Julika
Radecke
,
Lucile
Moynie
,
Yuguang
Zhao
,
Javier
Gilbert-Jaramillo
,
Michael L.
Knight
,
Julia A.
Tree
,
Karen R.
Buttigieg
,
Naomi
Coombes
,
Michael J.
Elmore
,
Miles W.
Carroll
,
Loic
Carrique
,
Pranav N. M.
Shah
,
William
James
,
Alain R.
Townsend
,
David I.
Stuart
,
Raymond J.
Owens
,
James H.
Naismith
Diamond Proposal Number(s):
[27031, 27051]
Open Access
Abstract: The SARS-CoV-2 virus is more transmissible than previous coronaviruses and causes a more serious illness than influenza. The SARS-CoV-2 receptor binding domain (RBD) of the spike protein binds to the human angiotensin-converting enzyme 2 (ACE2) receptor as a prelude to viral entry into the cell. Using a naive llama single-domain antibody library and PCR-based maturation, we have produced two closely related nanobodies, H11-D4 and H11-H4, that bind RBD (KD of 39 and 12 nM, respectively) and block its interaction with ACE2. Single-particle cryo-EM revealed that both nanobodies bind to all three RBDs in the spike trimer. Crystal structures of each nanobody–RBD complex revealed how both nanobodies recognize the same epitope, which partly overlaps with the ACE2 binding surface, explaining the blocking of the RBD–ACE2 interaction. Nanobody-Fc fusions showed neutralizing activity against SARS-CoV-2 (4–6 nM for H11-H4, 18 nM for H11-D4) and additive neutralization with the SARS-CoV-1/2 antibody CR3022.
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Jul 2020
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I02-Macromolecular Crystallography
I04-Macromolecular Crystallography
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Miriam
Walden
,
John M
Edwards
,
Aleksandra M
Dziewulska
,
Rene
Bergmann
,
Gerhard
Saalbach
,
Su-Yin
Kan
,
Ona K.
Miller
,
Miriam
Weckener
,
Rosemary J.
Jackson
,
Sally L.
Shirran
,
Catherine H.
Botting
,
Gordon J.
Florence
,
Manfred
Rohde
,
Mark J.
Banfield
,
Ulrich
Schwarz-Linek
Diamond Proposal Number(s):
[7641]
Open Access
Abstract: To cause disease and persist in a host, pathogenic and commensal microbes must adhere to tissues. Colonization and infection depend on specific molecular interactions at the host-microbe interface that involve microbial surface proteins, or adhesins. To date, adhesins are only known to bind to host receptors non-covalently. Here we show that the streptococcal surface protein SfbI mediates covalent interaction with the host protein fibrinogen using an unusual internal thioester bond as a ‘chemical harpoon’. This cross-linking reaction allows bacterial attachment to fibrin and SfbI binding to human cells in a model of inflammation. Thioester-containing domains are unexpectedly prevalent in Gram-positive bacteria, including many clinically relevant pathogens. Our findings support bacterial-encoded covalent binding as a new molecular principle in host-microbe interactions. This represents an as yet unexploited target to treat bacterial infection and may also offer novel opportunities for engineering beneficial interactions.
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Jun 2015
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