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  1. Article ; Online: Crystal structure of duck egg lysozyme isoform II (DEL-II).

    Langley, David B / Christ, Daniel

    BMC structural biology

    2018  Volume 18, Issue 1, Page(s) 10

    Abstract: Background: Lysozyme purified from duck eggs (DEL) has long been used as a model antigen as a counterpoint to the enzyme purified from hen eggs (HEL). However, unlike the single C-type variant found in hen eggs, duck eggs contain multiple isoforms: I, ... ...

    Abstract Background: Lysozyme purified from duck eggs (DEL) has long been used as a model antigen as a counterpoint to the enzyme purified from hen eggs (HEL). However, unlike the single C-type variant found in hen eggs, duck eggs contain multiple isoforms: I, II and III. We recently reported the structures of isoforms I and III from Pekin duck (Anas platyrhynchos) and unequivocally determined the sequences of all three isoforms by mass spectrometry. Here we present the crystal structure of isoform II (DEL-II).
    Results: Lysozyme isoform II was purified from isoforms I and III using ion-exchange and gel-filtration chromatography, then crystallized. X-ray diffraction data were collected to 1.15 Å resolution and the structure of DEL-II was solved by molecular replacement using the structure of DEL-I as the search model. It contains two molecules in the crystallographic asymmetric unit: both molecules display a canonical C-type lysozyme fold and electron density consistent with the expected sequence. The most significant difference between the two molecules concerns different conformations of a surface loop containing one of the expected amino acid differences between the isoforms.
    Conclusions: The structure of DEL-II supports the primary sequence as elucidated by a combination of amino acid sequencing, DNA sequencing and mass spectrometry, with strong electron density confirming it to be an S37G G71R variant of DEL I, and differing from hen egg lysozyme at a total of 21 amino acid positions.
    MeSH term(s) Animals ; Avian Proteins/chemistry ; Catalytic Domain ; Crystallography, X-Ray ; Ducks/metabolism ; Egg Proteins/chemistry ; Models, Molecular ; Muramidase/chemistry ; Protein Conformation ; Protein Isoforms/chemistry ; X-Ray Diffraction
    Chemical Substances Avian Proteins ; Egg Proteins ; Protein Isoforms ; Muramidase (EC 3.2.1.17)
    Language English
    Publishing date 2018-08-22
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2050440-8
    ISSN 1472-6807 ; 1472-6807
    ISSN (online) 1472-6807
    ISSN 1472-6807
    DOI 10.1186/s12900-018-0090-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Crystal structures of human neuropeptide Y (NPY) and peptide YY (PYY).

    Langley, David B / Schofield, Peter / Jackson, Jenny / Herzog, Herbert / Christ, Daniel

    Neuropeptides

    2022  Volume 92, Page(s) 102231

    Abstract: Neuropeptide Y (NPY), peptide YY (PYY) and pancreatic polypeptide (PP) form the evolutionarily conserved pancreatic polypeptide family. While the fold is widely utilized in nature, crystal structures remain elusive, particularly for the human forms, with ...

    Abstract Neuropeptide Y (NPY), peptide YY (PYY) and pancreatic polypeptide (PP) form the evolutionarily conserved pancreatic polypeptide family. While the fold is widely utilized in nature, crystal structures remain elusive, particularly for the human forms, with only the structure of a distant avian form of PP reported. Here we utilize a crystallization chaperone (antibody Fab fragment), specifically recognizing the amidated peptide termini, to solve the structures of human NPY and human PYY. Intriguingly, and despite limited sequence identity (~50%), the structure of human PYY closely resembles that of avian PP, highlighting the broad structural conservation of the fold throughout evolution. Specifically, the PYY structure is characterized by a C-terminal amidated α-helix, preceded by a backfolded poly-proline N-terminus, with the termini in close proximity to each other. In contrast, in the structure of human NPY the N-terminal component is disordered, while the helical component of the peptide is observed in a four-helix bundle type arrangement, consistent with a propensity for multimerization suggested by NMR studies.
    MeSH term(s) Humans ; Neuropeptide Y ; Pancreatic Polypeptide ; Peptide YY ; Receptors, Neuropeptide Y
    Chemical Substances Neuropeptide Y ; Receptors, Neuropeptide Y ; Peptide YY (106388-42-5) ; Pancreatic Polypeptide (59763-91-6)
    Language English
    Publishing date 2022-02-07
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 9048-7
    ISSN 1532-2785 ; 0143-4179
    ISSN (online) 1532-2785
    ISSN 0143-4179
    DOI 10.1016/j.npep.2022.102231
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  3. Article ; Online: Protein A superantigen: structure, engineering and molecular basis of antibody recognition.

    Mazigi, Ohan / Schofield, Peter / Langley, David B / Christ, Daniel

    Protein engineering, design & selection : PEDS

    2019  Volume 32, Issue 8, Page(s) 359–366

    Abstract: Staphylococcus aureus interacts with the human immune system through the production of secreted factors. Key among these is protein A, a B-cell superantigen capable of interacting with both antibody Fc and VH regions. Here, we review structural and ... ...

    Abstract Staphylococcus aureus interacts with the human immune system through the production of secreted factors. Key among these is protein A, a B-cell superantigen capable of interacting with both antibody Fc and VH regions. Here, we review structural and molecular features of this important example of naturally occurring bacterial superantigens, as well as engineered variants and their application in biotechnology.
    MeSH term(s) Amino Acid Sequence ; Humans ; Immunoglobulin Fc Fragments/chemistry ; Immunoglobulin Fc Fragments/genetics ; Immunoglobulin Fc Fragments/immunology ; Protein Binding ; Protein Engineering/methods ; Protein Folding ; Sequence Homology, Amino Acid ; Staphylococcal Protein A/chemistry ; Staphylococcal Protein A/genetics ; Staphylococcal Protein A/immunology ; Staphylococcus aureus/genetics ; Staphylococcus aureus/immunology ; Staphylococcus aureus/metabolism ; Superantigens/chemistry ; Superantigens/genetics ; Superantigens/immunology
    Chemical Substances Immunoglobulin Fc Fragments ; Staphylococcal Protein A ; Superantigens
    Language English
    Publishing date 2019-10-22
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 1466729-0
    ISSN 1741-0134 ; 1741-0126
    ISSN (online) 1741-0134
    ISSN 1741-0126
    DOI 10.1093/protein/gzz026
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Next-Generation Sequencing of Antibody Display Repertoires.

    Rouet, Romain / Jackson, Katherine J L / Langley, David B / Christ, Daniel

    Frontiers in immunology

    2018  Volume 9, Page(s) 118

    Abstract: ... In ... ...

    Abstract In vitro
    MeSH term(s) Antibodies ; Antibody Affinity ; Bacteriophages ; Epitope Mapping ; High-Throughput Nucleotide Sequencing ; Humans
    Chemical Substances Antibodies
    Language English
    Publishing date 2018-02-02
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 2606827-8
    ISSN 1664-3224
    ISSN 1664-3224
    DOI 10.3389/fimmu.2018.00118
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Surface-associated antigen induces permeabilization of primary mouse B-cells and lysosome exocytosis facilitating antigen uptake and presentation to T-cells.

    Maeda, Fernando Y / van Haaren, Jurriaan Jh / Langley, David B / Christ, Daniel / Andrews, Norma W / Song, Wenxia

    eLife

    2021  Volume 10

    Abstract: B-cell receptor (BCR)-mediated antigen internalization and presentation are essential for humoral memory immune responses. Antigen encountered by B-cells is often tightly associated with the surface of pathogens and/or antigen-presenting cells. ... ...

    Abstract B-cell receptor (BCR)-mediated antigen internalization and presentation are essential for humoral memory immune responses. Antigen encountered by B-cells is often tightly associated with the surface of pathogens and/or antigen-presenting cells. Internalization of such antigens requires myosin-mediated traction forces and extracellular release of lysosomal enzymes, but the mechanism triggering lysosomal exocytosis is unknown. Here, we show that BCR-mediated recognition of antigen tethered to beads, to planar lipid-bilayers or expressed on cell surfaces causes localized plasma membrane (PM) permeabilization, a process that requires BCR signaling and non-muscle myosin II activity. B-cell permeabilization triggers PM repair responses involving lysosomal exocytosis, and B-cells permeabilized by surface-associated antigen internalize more antigen than cells that remain intact. Higher affinity antigens cause more B-cell permeabilization and lysosomal exocytosis and are more efficiently presented to T-cells. Thus, PM permeabilization by surface-associated antigen triggers a lysosome-mediated B-cell resealing response, providing the extracellular hydrolases that facilitate antigen internalization and presentation.
    MeSH term(s) Animals ; Antigen Presentation/physiology ; Antigens, Surface ; B-Lymphocytes/immunology ; Cell Line ; Cell Membrane ; Exocytosis ; Lysosomes/metabolism ; Mice ; Mice, Inbred C57BL ; Mice, Transgenic ; Permeability ; Receptors, Antigen, B-Cell/immunology ; T-Lymphocytes/immunology
    Chemical Substances Antigens, Surface ; Receptors, Antigen, B-Cell
    Language English
    Publishing date 2021-10-27
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2687154-3
    ISSN 2050-084X ; 2050-084X
    ISSN (online) 2050-084X
    ISSN 2050-084X
    DOI 10.7554/eLife.66984
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  6. Article ; Online: Genetic and structural basis of the human anti-α-galactosyl antibody response.

    Langley, David B / Schofield, Peter / Nevoltris, Damien / Jackson, Jennifer / Jackson, Katherine J L / Peters, Tim J / Burk, Melanie / Matthews, Jacqueline M / Basten, Antony / Goodnow, Christopher C / van Nunen, Sheryl / Reed, Joanne H / Christ, Daniel

    Proceedings of the National Academy of Sciences of the United States of America

    2022  Volume 119, Issue 28, Page(s) e2123212119

    Abstract: Humans lack the capacity to produce the Galα1-3Galβ1-4GlcNAc (α-gal) glycan, and produce anti-α-gal antibodies upon exposure to the carbohydrate on a diverse set of immunogens, including commensal gut bacteria, malaria parasites, cetuximab, and tick ... ...

    Abstract Humans lack the capacity to produce the Galα1-3Galβ1-4GlcNAc (α-gal) glycan, and produce anti-α-gal antibodies upon exposure to the carbohydrate on a diverse set of immunogens, including commensal gut bacteria, malaria parasites, cetuximab, and tick proteins. Here we use X-ray crystallographic analysis of antibodies from α-gal knockout mice and humans in complex with the glycan to reveal a common binding motif, centered on a germline-encoded tryptophan residue at Kabat position 33 (W33) of the complementarity-determining region of the variable heavy chain (CDRH1). Immunoglobulin sequencing of anti-α-gal B cells in healthy humans and tick-induced mammalian meat anaphylaxis patients revealed preferential use of heavy chain germline IGHV3-7, encoding W33, among an otherwise highly polyclonal antibody response. Antigen binding was critically dependent on the presence of the germline-encoded W33 residue for all of the analyzed antibodies; moreover, introduction of the W33 motif into naive IGHV3-23 antibody phage libraries enabled the rapid selection of α-gal binders. Our results outline structural and genetic factors that shape the human anti-α-galactosyl antibody response, and provide a framework for future therapeutics development.
    MeSH term(s) Anaphylaxis/immunology ; Animals ; Antibodies/chemistry ; Antibodies/genetics ; Antibody Formation/genetics ; Antigen-Antibody Complex/chemistry ; Crystallography, X-Ray ; Food Hypersensitivity/immunology ; Humans ; Immunoglobulin Heavy Chains/chemistry ; Immunoglobulin Heavy Chains/genetics ; Immunoglobulin Variable Region/chemistry ; Immunoglobulin Variable Region/immunology ; Mice ; Mice, Knockout ; Peptide Library ; Protein Conformation ; Tick-Borne Diseases/immunology ; Trisaccharides/genetics ; Trisaccharides/immunology
    Chemical Substances Antibodies ; Antigen-Antibody Complex ; Immunoglobulin Heavy Chains ; Immunoglobulin Variable Region ; Peptide Library ; Trisaccharides ; alpha-galactosyl epitope
    Language English
    Publishing date 2022-07-08
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2123212119
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  7. Article ; Online: Conformational diversity facilitates antibody mutation trajectories and discrimination between foreign and self-antigens.

    Burnett, Deborah L / Schofield, Peter / Langley, David B / Jackson, Jennifer / Bourne, Katherine / Wilson, Emily / Porebski, Benjamin T / Buckle, Ashley M / Brink, Robert / Goodnow, Christopher C / Christ, Daniel

    Proceedings of the National Academy of Sciences of the United States of America

    2020  Volume 117, Issue 36, Page(s) 22341–22350

    Abstract: Conformational diversity and self-cross-reactivity of antigens have been correlated with evasion from neutralizing antibody responses. We utilized single cell B cell sequencing, biolayer interferometry and X-ray crystallography to trace mutation ... ...

    Abstract Conformational diversity and self-cross-reactivity of antigens have been correlated with evasion from neutralizing antibody responses. We utilized single cell B cell sequencing, biolayer interferometry and X-ray crystallography to trace mutation selection pathways where the antibody response must resolve cross-reactivity between foreign and self-proteins bearing near-identical contact surfaces, but differing in conformational flexibility. Recurring antibody mutation trajectories mediate long-range rearrangements of framework (FW) and complementarity determining regions (CDRs) that increase binding site conformational diversity. These antibody mutations decrease affinity for self-antigen 19-fold and increase foreign affinity 67-fold, to yield a more than 1,250-fold increase in binding discrimination. These results demonstrate how conformational diversity in antigen and antibody does not act as a barrier, as previously suggested, but rather facilitates high affinity and high discrimination between foreign and self.
    MeSH term(s) Animals ; Antibodies/chemistry ; Antibodies/genetics ; Antibodies/metabolism ; Antibody Affinity/genetics ; Antibody Diversity/genetics ; Autoantibodies/chemistry ; Autoantibodies/genetics ; Autoantibodies/metabolism ; Autoantigens/chemistry ; Autoantigens/metabolism ; Complementarity Determining Regions/genetics ; Gene Rearrangement, B-Lymphocyte/genetics ; Immunity, Humoral/genetics ; Mice ; Models, Molecular ; Mutation/genetics ; Protein Conformation ; Somatic Hypermutation, Immunoglobulin/genetics
    Chemical Substances Antibodies ; Autoantibodies ; Autoantigens ; Complementarity Determining Regions
    Language English
    Publishing date 2020-08-27
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2005102117
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  8. Article ; Online: Structure of GUN4 from Chlamydomonas reinhardtii.

    Tarahi Tabrizi, Shabnam / Langley, David B / Harrop, Stephen J / Duff, Anthony P / Willows, Robert D

    Acta crystallographica. Section F, Structural biology communications

    2015  Volume 71, Issue Pt 8, Page(s) 1094–1099

    Abstract: The genomes uncoupled 4 (GUN4) protein stimulates chlorophyll biosynthesis by increasing the activity of Mg-chelatase, the enzyme that inserts magnesium into protoporphyrin IX (PPIX) in the chlorophyll biosynthesis pathway. One of the roles of GUN4 is in ...

    Abstract The genomes uncoupled 4 (GUN4) protein stimulates chlorophyll biosynthesis by increasing the activity of Mg-chelatase, the enzyme that inserts magnesium into protoporphyrin IX (PPIX) in the chlorophyll biosynthesis pathway. One of the roles of GUN4 is in binding PPIX and Mg-PPIX. In eukaryotes, GUN4 also participates in plastid-to-nucleus signalling, although the mechanism for this is unclear. Here, the first crystal structure of a eukaryotic GUN4, from Chlamydomonas reinhardtii, is presented. The structure is in broad agreement with those of previously solved cyanobacterial structures. Most interestingly, conformational divergence is restricted to several loops which cover the porphyrin-binding cleft. The conformational dynamics suggested by this ensemble of structures lend support to the understanding of how GUN4 binds PPIX or Mg-PPIX.
    MeSH term(s) Algal Proteins/chemistry ; Algal Proteins/genetics ; Amino Acid Sequence ; Base Sequence ; Binding Sites ; Chlamydomonas reinhardtii/chemistry ; Chlamydomonas reinhardtii/genetics ; Cloning, Molecular ; Crystallization ; Crystallography, X-Ray ; Escherichia coli/genetics ; Escherichia coli/metabolism ; Gene Expression ; Models, Molecular ; Molecular Sequence Data ; Protein Binding ; Protein Folding ; Protein Structure, Secondary ; Protein Structure, Tertiary ; Protoporphyrins/chemistry ; Recombinant Fusion Proteins/chemistry ; Recombinant Fusion Proteins/genetics ; Sequence Alignment
    Chemical Substances Algal Proteins ; Protoporphyrins ; Recombinant Fusion Proteins ; magnesium protoporphyrin (14947-11-6) ; protoporphyrin IX (C2K325S808)
    Language English
    Publishing date 2015-07-29
    Publishing country United States
    Document type Journal Article
    ISSN 2053-230X
    ISSN (online) 2053-230X
    DOI 10.1107/S2053230X15012248
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  9. Article ; Online: Broadly neutralizing SARS-CoV-2 antibodies through epitope-based selection from convalescent patients.

    Rouet, Romain / Henry, Jake Y / Johansen, Matt D / Sobti, Meghna / Balachandran, Harikrishnan / Langley, David B / Walker, Gregory J / Lenthall, Helen / Jackson, Jennifer / Ubiparipovic, Stephanie / Mazigi, Ohan / Schofield, Peter / Burnett, Deborah L / Brown, Simon H J / Martinello, Marianne / Hudson, Bernard / Gilroy, Nicole / Post, Jeffrey J / Kelleher, Anthony /
    Jäck, Hans-Martin / Goodnow, Christopher C / Turville, Stuart G / Rawlinson, William D / Bull, Rowena A / Stewart, Alastair G / Hansbro, Philip M / Christ, Daniel

    Nature communications

    2023  Volume 14, Issue 1, Page(s) 687

    Abstract: Emerging variants of concern (VOCs) are threatening to limit the effectiveness of SARS-CoV-2 monoclonal antibodies and vaccines currently used in clinical practice; broadly neutralizing antibodies and strategies for their identification are therefore ... ...

    Abstract Emerging variants of concern (VOCs) are threatening to limit the effectiveness of SARS-CoV-2 monoclonal antibodies and vaccines currently used in clinical practice; broadly neutralizing antibodies and strategies for their identification are therefore urgently required. Here we demonstrate that broadly neutralizing antibodies can be isolated from peripheral blood mononuclear cells of convalescent patients using SARS-CoV-2 receptor binding domains carrying epitope-specific mutations. This is exemplified by two human antibodies, GAR05, binding to epitope class 1, and GAR12, binding to a new epitope class 6 (located between class 3 and 5). Both antibodies broadly neutralize VOCs, exceeding the potency of the clinical monoclonal sotrovimab (S309) by orders of magnitude. They also provide prophylactic and therapeutic in vivo protection of female hACE2 mice against viral challenge. Our results indicate that exposure to SARS-CoV-2 induces antibodies that maintain broad neutralization against emerging VOCs using two unique strategies: either by targeting the divergent class 1 epitope in a manner resistant to VOCs (ACE2 mimicry, as illustrated by GAR05 and mAbs P2C-1F11/S2K14); or alternatively, by targeting rare and highly conserved epitopes, such as the new class 6 epitope identified here (as illustrated by GAR12). Our results provide guidance for next generation monoclonal antibody development and vaccine design.
    MeSH term(s) Humans ; Female ; Animals ; Mice ; SARS-CoV-2 ; Broadly Neutralizing Antibodies ; Leukocytes, Mononuclear ; COVID-19 ; Antibodies, Viral ; Antibodies, Monoclonal ; Antibodies, Neutralizing ; Epitopes ; Spike Glycoprotein, Coronavirus/genetics ; Neutralization Tests
    Chemical Substances Broadly Neutralizing Antibodies ; Antibodies, Viral ; Antibodies, Monoclonal ; Antibodies, Neutralizing ; Epitopes ; Spike Glycoprotein, Coronavirus ; spike protein, SARS-CoV-2
    Language English
    Publishing date 2023-02-08
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-023-36295-5
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  10. Article ; Online: Human Antibody Bispecifics through Phage Display Selection.

    Luthra, Ansha / Langley, David B / Schofield, Peter / Jackson, Jennifer / Abdelatti, Mahmoud / Rouet, Romain / Nevoltris, Damien / Mazigi, Ohan / Crossett, Ben / Christie, Mary / Christ, Daniel

    Biochemistry

    2019  Volume 58, Issue 13, Page(s) 1701–1704

    Abstract: We developed a repertoire approach to generate human antibody bispecifics. Using phage display selection of antibody heavy chains in the presence of a competitor light chain and providing a cognate light chain with an affinity handle, we identified ... ...

    Abstract We developed a repertoire approach to generate human antibody bispecifics. Using phage display selection of antibody heavy chains in the presence of a competitor light chain and providing a cognate light chain with an affinity handle, we identified mutations that prevent heavy/light chain mispairing. The strategy allows for the selection of human antibody chains that autonomously assemble into bispecifics.
    MeSH term(s) Amino Acid Sequence ; Antibodies, Bispecific/chemistry ; Antibodies, Bispecific/immunology ; Antibody Affinity ; Humans ; Immunoglobulin Heavy Chains/chemistry ; Immunoglobulin Heavy Chains/immunology ; Immunoglobulin Light Chains/chemistry ; Immunoglobulin Light Chains/immunology ; Models, Molecular ; Peptide Library
    Chemical Substances Antibodies, Bispecific ; Immunoglobulin Heavy Chains ; Immunoglobulin Light Chains ; Peptide Library
    Language English
    Publishing date 2019-03-22
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1108-3
    ISSN 1520-4995 ; 0006-2960
    ISSN (online) 1520-4995
    ISSN 0006-2960
    DOI 10.1021/acs.biochem.9b00037
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