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Herrera MG, Amundarain MJ, Dörfler PW, Dodero VI. The Celiac-Disease Superantigen Oligomerizes and Increases Permeability in an Enterocyte Cell Model. Angew Chem Int Ed Engl 2024; 63:e202317552. [PMID: 38497459 DOI: 10.1002/anie.202317552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 03/03/2024] [Accepted: 03/05/2024] [Indexed: 03/19/2024]
Abstract
Celiac disease (CeD) is an autoimmune disorder triggered by gluten proteins, affecting approximately 1 % of the global population. The 33-mer deamidated gliadin peptide (DGP) is a metabolically modified wheat-gluten superantigen for CeD. Here, we demonstrate that the 33-mer DGP spontaneously assembles into oligomers with a diameter of approximately 24 nm. The 33-mer DGP oligomers present two main secondary structural motifs-a major polyproline II helix and a minor β-sheet structure. Importantly, in the presence of 33-mer DGP oligomers, there is a statistically significant increase in the permeability in the gut epithelial cell model Caco-2, accompanied by the redistribution of zonula occludens-1, a master tight junction protein. These findings provide novel molecular and supramolecular insights into the impact of 33-mer DGP in CeD and highlight the relevance of gliadin peptide oligomerization.
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Affiliation(s)
- Maria G Herrera
- Department of Chemistry, Bielefeld University, Universitätsstr. 25, 33615, Bielefeld, Germany
- Department of Physiology and Molecular and Cellular Biology, Institute of Biosciences, Biotechnology and Translational Biology (iB3), Faculty of Exact and Natural Sciences, University of Buenos Aires, Buenos Aires, C1428EG, Argentina
| | - Maria J Amundarain
- Department of Chemistry, Bielefeld University, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Philipp W Dörfler
- Department of Chemistry, Bielefeld University, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Veronica I Dodero
- Department of Chemistry, Bielefeld University, Universitätsstr. 25, 33615, Bielefeld, Germany
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2
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Borowska MT, Drees C, Yarawsky AE, Viswanathan M, Ryan SM, Bunker JJ, Herr AB, Bendelac A, Adams EJ. The molecular characterization of antibody binding to a superantigen-like protein from a commensal microbe. Proc Natl Acad Sci U S A 2021; 118:e2023898118. [PMID: 34548394 PMCID: PMC8488583 DOI: 10.1073/pnas.2023898118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/13/2021] [Indexed: 11/18/2022] Open
Abstract
Microorganisms have coevolved diverse mechanisms to impair host defenses. A major one, superantigens, can result in devastating effects on the immune system. While all known superantigens induce vast immune cell proliferation and come from opportunistic pathogens, recently, proteins with similar broad specificity to antibody variable (V) domain families were identified in a commensal microbiota. These proteins, identified in the human commensal Ruminococcus gnavus, are called immunoglobulin-binding protein (Ibp) A and B and have been shown to activate B cells in vitro expressing either human VH3 or murine VH5/6/7. Here, we provide molecular and functional studies revealing the basis of this Ibp/immunoglobulin (Ig) interaction. The crystal structure and biochemical assays of a truncated IbpA construct in complex with mouse VH5 antigen-binding fragment (Fab) shows a binding of Ig heavy chain framework residues to the Ibp Domain D and the C-terminal heavy chain binding domain (HCBD). We used targeted mutagenesis of contact residues and affinity measurements and performed studies of the Fab-IbpA complex to determine the stoichiometry between Ibp and VH domains, suggesting Ibp may serve to cluster full-length IgA antibodies in vivo. Furthermore, in vitro stimulation experiments indicate that binding of the Ibp HCBD alone is sufficient to activate responsive murine B cell receptors. The presence of these proteins in a commensal microbe suggest that binding a broad repertoire of immunoglobulins, particularly in the gut/microbiome environment, may provide an important function in the maintenance of host/microbiome homeostasis contrasting with the pathogenic role of structurally homologous superantigens expressed by pathogens.
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Affiliation(s)
- Marta T Borowska
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637
| | - Christoph Drees
- Department of Pathology, University of Chicago, Chicago, IL 60637
| | - Alexander E Yarawsky
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229
| | | | - Sean M Ryan
- Committee on Immunology, University of Chicago, Chicago, IL 60637
| | - Jeffrey J Bunker
- Department of Pathology, University of Chicago, Chicago, IL 60637
- Committee on Immunology, University of Chicago, Chicago, IL 60637
| | - Andrew B Herr
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229
- Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229
| | - Albert Bendelac
- Department of Pathology, University of Chicago, Chicago, IL 60637;
- Committee on Immunology, University of Chicago, Chicago, IL 60637
| | - Erin J Adams
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637;
- Committee on Immunology, University of Chicago, Chicago, IL 60637
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Gröger V, Wieland L, Naumann M, Meinecke AC, Meinhardt B, Rossner S, Ihling C, Emmer A, Staege MS, Cynis H. Formation of HERV-K and HERV-Fc1 Envelope Family Members is Suppressed on Transcriptional and Translational Level. Int J Mol Sci 2020; 21:ijms21217855. [PMID: 33113941 PMCID: PMC7660216 DOI: 10.3390/ijms21217855] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 10/15/2020] [Accepted: 10/21/2020] [Indexed: 12/12/2022] Open
Abstract
The human genome comprises 8% sequences of retroviral origin, so-called human endogenous retroviruses (HERVs). Most of these proviral sequences are defective, but some possess open reading frames. They can lead to the formation of viral transcripts, when activated by intrinsic and extrinsic factors. HERVs are thought to play a pathological role in inflammatory diseases and cancer. Since the consequences of activated proviral sequences in the human body are largely unexplored, selected envelope proteins of human endogenous retroviruses associated with inflammatory diseases, namely HERV-K18, HERV-K113, and HERV-Fc1, were investigated in the present study. A formation of glycosylated envelope proteins was demonstrated in different mammalian cell lines. Nevertheless, protein maturation seemed to be incomplete as no transport to the plasma membrane was observed. Instead, the proteins remained in the ER where they induced the expression of genes involved in unfolded protein response, such as HSPA5 and sXBP1. Furthermore, low expression levels of native envelope proteins were increased by codon optimization. Cell-free expression systems showed that both the transcriptional and translational level is affected. By generating different codon-optimized variants of HERV-K113 envelope, the influence of single rare t-RNA pools in certain cell lines was demonstrated. The mRNA secondary structure also appears to play an important role in the translation of the tested viral envelope proteins. In summary, the formation of certain HERV proteins is basically possible. However, their complete maturation and thus full biologic activity seems to depend on additional factors that might be disease-specific and await elucidation in the future.
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Affiliation(s)
- Victoria Gröger
- Department of Drug Design and Target Validation, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany; (V.G.); (M.N.); (A.-C.M.)
| | - Lisa Wieland
- Department of Neurology, Medical Faculty, Martin Luther University Halle-Wittenberg, Ernst-Grube-Str. 40, 06097 Halle, Germany; (L.W.); (B.M.); (A.E.)
- Department of Surgical and Conservative Pediatrics and Adolescent Medicine, Medical Faculty, Martin Luther University Halle-Wittenberg, Ernst-Grube-Str. 40, 06097 Halle, Germany
| | - Marcel Naumann
- Department of Drug Design and Target Validation, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany; (V.G.); (M.N.); (A.-C.M.)
| | - Ann-Christin Meinecke
- Department of Drug Design and Target Validation, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany; (V.G.); (M.N.); (A.-C.M.)
| | - Beate Meinhardt
- Department of Neurology, Medical Faculty, Martin Luther University Halle-Wittenberg, Ernst-Grube-Str. 40, 06097 Halle, Germany; (L.W.); (B.M.); (A.E.)
- Department of Surgical and Conservative Pediatrics and Adolescent Medicine, Medical Faculty, Martin Luther University Halle-Wittenberg, Ernst-Grube-Str. 40, 06097 Halle, Germany
| | - Steffen Rossner
- Paul Flechsig Institute for Brain Research, Leipzig University, Liebigstraße 19, 04103 Leipzig, Germany;
| | - Christian Ihling
- Department of Pharmaceutical Chemistry & Bioanalytics, Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Charles Tanford Protein Center, Kurt-Mothes-Str. 3a, 06120 Halle, Germany;
| | - Alexander Emmer
- Department of Neurology, Medical Faculty, Martin Luther University Halle-Wittenberg, Ernst-Grube-Str. 40, 06097 Halle, Germany; (L.W.); (B.M.); (A.E.)
| | - Martin S. Staege
- Department of Surgical and Conservative Pediatrics and Adolescent Medicine, Medical Faculty, Martin Luther University Halle-Wittenberg, Ernst-Grube-Str. 40, 06097 Halle, Germany
- Correspondence: (M.S.S.); (H.C.); Tel.: +49-345-5577280 (M.S.S.); +49-345-13142835 (H.C.); Fax: +49-345-5577275 (M.S.S.); +49-345-13142801 (H.C.)
| | - Holger Cynis
- Department of Drug Design and Target Validation, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany; (V.G.); (M.N.); (A.-C.M.)
- Correspondence: (M.S.S.); (H.C.); Tel.: +49-345-5577280 (M.S.S.); +49-345-13142835 (H.C.); Fax: +49-345-5577275 (M.S.S.); +49-345-13142801 (H.C.)
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Etter D, Schelin J, Schuppler M, Johler S. Staphylococcal Enterotoxin C-An Update on SEC Variants, Their Structure and Properties, and Their Role in Foodborne Intoxications. Toxins (Basel) 2020; 12:E584. [PMID: 32927913 PMCID: PMC7551944 DOI: 10.3390/toxins12090584] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/07/2020] [Accepted: 09/08/2020] [Indexed: 12/20/2022] Open
Abstract
Staphylococcal enterotoxins are the most common cause of foodborne intoxications (staphylococcal food poisoning) and cause a wide range of diseases. With at least six variants staphylococcal enterotoxin C (SEC) stands out as particularly diverse amongst the 25 known staphylococcal enterotoxins. Some variants present unique and even host-specific features. Here, we review the role of SEC in human and animal health with a particular focus on its role as a causative agent for foodborne intoxications. We highlight structural features unique to SEC and its variants, particularly, the emetic and superantigen activity, as well as the roles of SEC in mastitis and in dairy products. Information about the genetic organization as well as regulatory mechanisms including the accessory gene regulator and food-related stressors are provided.
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Affiliation(s)
- Danai Etter
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zürich, 8057 Zürich, Switzerland;
- Laboratory of Food Microbiology, Institute of Food, Nutrition and Health, ETH Zürich, 8092 Zürich, Switzerland;
| | - Jenny Schelin
- Division of Applied Microbiology, Department of Chemistry, Lund University, 22100 Lund, Sweden;
| | - Markus Schuppler
- Laboratory of Food Microbiology, Institute of Food, Nutrition and Health, ETH Zürich, 8092 Zürich, Switzerland;
| | - Sophia Johler
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zürich, 8057 Zürich, Switzerland;
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5
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Zeng C, Liu Z, Han Z. Structure of Staphylococcal Enterotoxin N: Implications for Binding Properties to Its Cellular Proteins. Int J Mol Sci 2019; 20:ijms20235921. [PMID: 31775346 PMCID: PMC6928602 DOI: 10.3390/ijms20235921] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Revised: 11/20/2019] [Accepted: 11/22/2019] [Indexed: 01/26/2023] Open
Abstract
Staphylococcus aureus strains produce a unique family of immunostimulatory exotoxins termed as bacterial superantigens (SAgs), which cross-link major histocompatibility complex class II (MHC II) molecule and T-cell receptor (TCR) to stimulate large numbers of T cells at extremely low concentrations. SAgs are associated with food poisoning and toxic shock syndrome. To date, 26 genetically distinct staphylococcal SAgs have been reported. This study reports the first X-ray structure of newly characterized staphylococcal enterotoxin N (SEN). SEN possesses the classical two domain architecture that includes an N-terminal oligonucleotide-binding fold and a C-terminal β-grasp domain. Amino acid and structure alignments revealed that several critical amino acids that are proposed to be responsible for MHC II and TCR molecule engagements are variable in SEN, suggesting that SEN may adopt a different binding mode to its cellular receptors. This work helps better understand the mechanisms of action of SAgs.
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Affiliation(s)
- Chi Zeng
- College of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan 430023, China; (C.Z.); (Z.L.)
- Hubei Province Fresh Food Engineering Research Center, Wuhan Polytechnic University, Wuhan 430023, China
- Key Laboratory of Prevention and Control Agents for Animal Bacteriosis (Ministry of Agriculture), Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
| | - Zhaoxin Liu
- College of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan 430023, China; (C.Z.); (Z.L.)
- College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Zhenggang Han
- College of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan 430023, China; (C.Z.); (Z.L.)
- Correspondence:
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6
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Abstract
Superantigens secreted by Staphylococcus aureus and Streptococcus pyogenes interact with the T-cell receptor and major histocompatibility class II molecules on antigen-presenting cells to elicit a massive cytokine release and activation of T cells in higher numbers than that seen with ordinary antigens. Because of this unique ability, superantigens have been implicated as etiological agents for many different types of diseases, including toxic shock syndrome, infective endocarditis, pneumonia, and inflammatory skin diseases. This review covers the main animal models that have been developed in order to identify the roles of superantigens in human disease.
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Affiliation(s)
- Amanda J Brosnahan
- Department of Science, Concordia University - Saint Paul, 1282 Concordia Ave., S-115, St. Paul, MN, 55104, USA.
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7
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Dutta D, Dutta A, Bhattacharjee A, Basak A, Das AK. Cloning, expression, crystallization and preliminary X-ray diffraction studies of staphylococcal superantigen-like protein 1 (SSL1). Acta Crystallogr F Struct Biol Commun 2014; 70:600-3. [PMID: 24817718 PMCID: PMC4014327 DOI: 10.1107/s2053230x14006967] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Accepted: 03/28/2014] [Indexed: 05/03/2024] Open
Abstract
Staphylococcus aureus produces a family of exotoxins which are structural homologues of superantigens and thus are called staphylococcal superantigen-like proteins (SSLs). Amongst the 14 SSL genes, ssl1 (SAOUHSC_00383) has been cloned in the pQE30 expression vector, overexpressed in Escherichia coli M15 (pREP4) cells and the protein purified to homogeneity. The protein was crystallized using 6% Tacsimate pH 6.0, 0.1 M MES pH 6.0, 25%(w/v) polyethylene glycol 3350, 100 mM NDSB 256 at 298 K by the sitting-drop vapour-diffusion method. The crystals belonged to space group P21, with unit-cell parameters a = 77.9, b = 70.5, c = 126.5 Å, β = 106.2°. X-ray diffraction data were collected and processed to a maximum resolution of 2.5 Å. The crystal contains six molecules in the asymmetric unit.
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Affiliation(s)
- Debabrata Dutta
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721 302, India
| | - Anirudha Dutta
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721 302, India
| | - Atanu Bhattacharjee
- Department of Biotechnology and Bioinformatics, North Eastern Hill University, Shillong 793 022, India
| | - Amit Basak
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721 302, India
| | - Amit Kumar Das
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721 302, India
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8
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Sharma P, Wang N, Kranz DM. Soluble T cell receptor Vβ domains engineered for high-affinity binding to staphylococcal or streptococcal superantigens. Toxins (Basel) 2014; 6:556-74. [PMID: 24476714 PMCID: PMC3942751 DOI: 10.3390/toxins6020556] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 01/21/2014] [Accepted: 01/22/2014] [Indexed: 11/29/2022] Open
Abstract
Staphylococcus aureus and group A Streptococcus secrete a collection of toxins called superantigens (SAgs), so-called because they stimulate a large fraction of an individual’s T cells. One consequence of this hyperactivity is massive cytokine release leading to severe tissue inflammation and, in some cases, systemic organ failure and death. The molecular basis of action involves the binding of the SAg to both a T cell receptor (TCR) on a T cell and a class II product of the major histocompatibility complex (MHC) on an antigen presenting cell. This cross-linking leads to aggregation of the TCR complex and signaling. A common feature of SAgs is that they bind with relatively low affinity to the variable region (V) of the beta chain of the TCR. Despite this low affinity binding, SAgs are very potent, as each T cell requires only a small fraction of their receptors to be bound in order to trigger cytokine release. To develop high-affinity agents that could neutralize the activity of SAgs, and facilitate the development of detection assays, soluble forms of the Vβ regions have been engineered to affinities that are up to 3 million-fold higher for the SAg. Over the past decade, six different Vβ regions against SAgs from S. aureus (SEA, SEB, SEC3, TSST-1) or S. pyogenes (SpeA and SpeC) have been engineered for high-affinity using yeast display and directed evolution. Here we review the engineering of these high-affinity Vβ proteins, structural features of the six different SAgs and the Vβ proteins, and the specific properties of the engineered Vβ regions that confer high-affinity and specificity for their SAg ligands.
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Affiliation(s)
- Preeti Sharma
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA.
| | - Ningyan Wang
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA.
| | - David M Kranz
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA.
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Liu L, Chen H, Brecher MB, Li Z, Wei B, Nandi B, Zhang J, Ling H, Winslow G, Braun J, Li H. Pfit is a structurally novel Crohn's disease-associated superantigen. PLoS Pathog 2013; 9:e1003837. [PMID: 24385909 PMCID: PMC3873459 DOI: 10.1371/journal.ppat.1003837] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 11/02/2013] [Indexed: 01/07/2023] Open
Abstract
T cell responses to enteric bacteria are important in inflammatory bowel disease. I2, encoded by the pfiT gene of Pseudomonas fluorescens, is a T-cell superantigen associated with human Crohn's disease. Here we report the crystal structure of pfiT at 1.7Å resolution and provide a functional analysis of the interaction of pfiT and its homolog, PA2885, with human class II MHC. Both pfiT and PA2885 bound to mammalian cells and stimulated the proliferation of human lymphocytes. This binding was greatly inhibited by anti-class II MHC HLA-DR antibodies, and to a lesser extent, by anti HLA-DQ and DP antibodies, indicating that the binding was class II MHC-specific. GST-pfiT efficiently precipitated both endogenous and in vitro purified recombinant HLA-DR1 molecules, indicating that pfiT directly interacted with HLA-DR1. Competition studies revealed that pfiT and the superantigen Mycoplasma arthritidis mitogen (MAM) competed for binding to HLA-DR, indicating that their binding sites overlap. Structural analyses established that pfiT belongs to the TetR-family of DNA-binding transcription regulators. The distinct structure of pfiT indicates that it represents a new family of T cell superantigens. Human inflammatory bowel disease (IBD) is a family of chronic inflammatory disorders of the gastrointestinal tract which affect genetically susceptible individuals. IBD is a lifelong disease involving mostly young people, often severely. Crohn's disease (CD) and ulcerative colitis are the two major forms of IBD. Although the exact cause of these diseases remains unknown, both genetic and environmental factors together play significant roles in the disease pathogenesis. Several lines of evidence implicate commensal bacteria as an important pathogenic element in clinical disease, particularly in CD. We recently identified a novel microbial gene, I2, encoded by Pseudomonas fluorescens, a gram-negative commensal, which may be involved in the pathogenesis of CD. Both molecular and immunological approaches were used to identify the human receptor for the microbial antigen encoded by I2, to characterize the ligand-receptor interactions, and to determine the three-dimensional structure of the microbial gene product. In particular, we show that the pfiT is a T cell superantigen, which may help to explain how microbial flora can trigger immune activation in IBD, and may provide the groundwork for novel therapies to treat CD.
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Affiliation(s)
- Lihui Liu
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Hui Chen
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Matthew B. Brecher
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Zhong Li
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Bo Wei
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, United States of America
| | - Bisweswar Nandi
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Jing Zhang
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Hua Ling
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Gary Winslow
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
- Department of Biomedical Sciences, School of Public Health, State University of New York, Albany, New York, United States of America
| | - Jonathan Braun
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, United States of America
| | - Hongmin Li
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
- Department of Biomedical Sciences, School of Public Health, State University of New York, Albany, New York, United States of America
- * E-mail:
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Zaraket H, Otsuka T, Saito K, Dohmae S, Takano T, Higuchi W, Ohkubo T, Ozaki K, Takano M, Reva I, Baranovich T, Yamamoto T. Molecular Characterization of Methicillin-ResistantStaphylococcus aureusin Hospitals in Niigata, Japan: Divergence and Transmission. Microbiol Immunol 2013; 51:171-6. [PMID: 17310084 DOI: 10.1111/j.1348-0421.2007.tb03898.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The major methicillin-resistant Staphylococcus aureus(MRSA) distributed among hospitals in Japan is New York/Japan clone [multilocus sequence type 5 (ST5), agr type 2 and methicillin resistance locus type (SCC mec) II] which possesses both the toxic shock syndrome toxin 1 gene (tst) and staphylococcal enterotoxin C gene (sec). In this study, we collected 245 MRSA strains from four hospitals during 2001 to 2005 in Niigata, Japan, and analyzed tst and sec genes and SCC mec type among them. A total of 13 strains were further examined for their genotypes, virulence gene patterns and drug resistance. Among the 245 strains four tst sec genes patterns were observed; tst(+) sec(+) strains represented a majority of 86.5% and 9.4% were tst(-) sec(-). SCCmec typing revealed that 91.4% had type II, 4.1% type IV and 4.1% type I. Multilocus sequence typing (MLST) revealed that 10 of the 13 typed strains belonged to clonal complex 5 (7 had ST5 while 3 were single locus variants of ST5) with similar characteristics to the New York/Japan clone and possessed multi-drug resistance with high virulence gene content. The remaining 3 strains were ST8 (n=2) and ST91 (n=1). The ST91 strain had SCC mec IV and seemed to originate in the community, while ST8 strains exhibited SCC mec type I, which is distinct from community type IV. The data suggest that MRSA in hospitals in Niigata now mainly includes the New York/Japan clone (undergoing genomic divergence and clonal expansion) and other minor types (e.g. ST8) as well as the community type.
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Affiliation(s)
- Hassan Zaraket
- Division of Bacteriology, Department of Infectious Disease Control and International Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
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11
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Hu H, Armstrong PCJ, Khalil E, Chen YC, Straub A, Li M, Soosairajah J, Hagemeyer CE, Bassler N, Huang D, Ahrens I, Krippner G, Gardiner E, Peter K. GPVI and GPIbα mediate staphylococcal superantigen-like protein 5 (SSL5) induced platelet activation and direct toward glycans as potential inhibitors. PLoS One 2011; 6:e19190. [PMID: 21552524 PMCID: PMC3084272 DOI: 10.1371/journal.pone.0019190] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Accepted: 03/22/2011] [Indexed: 11/29/2022] Open
Abstract
Background Staphylococcus aureus (S. aureus) is a common pathogen capable of causing life-threatening infections. Staphylococcal superantigen-like protein 5 (SSL5) has recently been shown to bind to platelet glycoproteins and induce platelet activation. This study investigates further the interaction between SSL5 and platelet glycoproteins. Moreover, using a glycan discovery approach, we aim to identify potential glycans to therapeutically target this interaction and prevent SSL5-induced effects. Methodology/Principal Findings In addition to platelet activation experiments, flow cytometry, immunoprecipitation, surface plasmon resonance and a glycan binding array, were used to identify specific SSL5 binding regions and mediators. We independently confirm SSL5 to interact with platelets via GPIbα and identify the sulphated-tyrosine residues as an important region for SSL5 binding. We also identify the novel direct interaction between SSL5 and the platelet collagen receptor GPVI. Together, these receptors offer one mechanistic explanation for the unique functional influences SSL5 exerts on platelets. A role for specific families of platelet glycans in mediating SSL5-platelet interactions was also discovered and used to identify and demonstrate effectiveness of potential glycan based inhibitors in vitro. Conclusions/Significance These findings further elucidate the functional interactions between SSL5 and platelets, including the novel finding of a role for the GPVI receptor. We demonstrate efficacy of possible glycan-based approaches to inhibit the SSL5-induced platelet activation. Our data warrant further work to prove SSL5-platelet effects in vivo.
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Affiliation(s)
- Houyuan Hu
- Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
- Department of Cardiology, Southwest Hospital, Third Military Medical University, Chongqing, China
| | | | - Elie Khalil
- Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
| | - Yung-Chih Chen
- Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
- Department of Medicine, Monash University, Melbourne, Victoria, Australia
| | - Andreas Straub
- Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
| | - Min Li
- Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
- Department of Cardiology, Southwest Hospital, Third Military Medical University, Chongqing, China
| | | | | | - Nicole Bassler
- Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
| | - Dexing Huang
- Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
| | - Ingo Ahrens
- Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
| | - Guy Krippner
- Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
| | - Elizabeth Gardiner
- Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria, Australia
| | - Karlheinz Peter
- Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
- Department of Medicine, Monash University, Melbourne, Victoria, Australia
- * E-mail:
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12
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Sun J, Zhao L, Teng L, Lin F, Zhang H, Li Z, Gao Q. Solid tumor-targeted infiltrating cytotoxic T lymphocytes retained by a superantigen fusion protein. PLoS One 2011; 6:e16642. [PMID: 21311755 PMCID: PMC3032773 DOI: 10.1371/journal.pone.0016642] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Accepted: 01/07/2011] [Indexed: 11/19/2022] Open
Abstract
Successful immune-mediated regression of solid tumors is difficult because of the small number of cytotoxic T lymphocytes (CTLs) that were traffic to the tumor site. Here, the targeting of tumor-specific infiltrating CTLs was dependent on a fusion protein consisting of human epidermal growth factor (EGF) and staphylococcal enterotoxin A (SEA) with the D227A mutation. EGF-SEA strongly restrained the growth of murine solid sarcoma 180 (S180) tumors (control versus EGF-SEA, mean tumor weight: 1.013 versus 0.197 g, difference = 0.816 g). In mice treated with EGF-SEA, CD4+, CD8+ and SEA-reactive T lymphocytes were enriched around the EGFR expressing tumor cells. The EGF receptors were potentially phosphorylated by EGF-SEA stimulation and the fusion protein promoted T cells to release the tumoricidal cytokines interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α). Intratumoral CTLs secreted cytolytic pore-forming perforins and granzyme B proteins near the surface of carcinomas, causing the death of many tumor cells. We additionally show that labeled EGF-SEA was directly targeted to the tumor tissue after intravenous (i.v.) injection. The findings demonstrate that antibody-like EGF-SEA plays an important role in arresting CTLs in the solid tumor site and has therapeutic potential as a tumor-targeting agent.
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MESH Headings
- Amino Acid Substitution/genetics
- Amino Acid Substitution/physiology
- Animals
- Cells, Cultured
- Chemotaxis, Leukocyte/immunology
- Chemotaxis, Leukocyte/physiology
- Cytotoxicity, Immunologic/immunology
- Enterotoxins/chemistry
- Enterotoxins/genetics
- Enterotoxins/immunology
- Enterotoxins/therapeutic use
- Humans
- Immunotherapy, Adoptive/methods
- Lymphocytes, Tumor-Infiltrating/cytology
- Lymphocytes, Tumor-Infiltrating/immunology
- Lymphocytes, Tumor-Infiltrating/physiology
- Male
- Mice
- Mice, Inbred ICR
- Mutation, Missense
- Recombinant Fusion Proteins/chemistry
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/immunology
- Recombinant Fusion Proteins/physiology
- Superantigens/chemistry
- Superantigens/immunology
- Superantigens/physiology
- T-Lymphocytes, Cytotoxic/cytology
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/physiology
- Tumor Necrosis Factor-alpha/chemistry
- Tumor Necrosis Factor-alpha/genetics
- Tumor Necrosis Factor-alpha/immunology
- Tumor Necrosis Factor-alpha/therapeutic use
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Affiliation(s)
- Jialin Sun
- Key Laboratory of Industrial Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, People's Republic of China.
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13
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Fernández MM, Cho S, De Marzi MC, Kerzic MC, Robinson H, Mariuzza RA, Malchiodi EL. Crystal structure of staphylococcal enterotoxin G (SEG) in complex with a mouse T-cell receptor {beta} chain. J Biol Chem 2011; 286:1189-95. [PMID: 21059660 PMCID: PMC3020726 DOI: 10.1074/jbc.m110.142471] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2010] [Revised: 09/20/2010] [Indexed: 11/06/2022] Open
Abstract
Superantigens (SAgs) are bacterial or viral toxins that bind MHC class II (MHC-II) molecules and T-cell receptor (TCR) in a nonconventional manner, inducing T-cell activation that leads to inflammatory cytokine production, which may result in acute toxic shock. In addition, the emerging threat of purpura fulminans and community-associated meticillin-resistant Staphylococcus aureus emphasizes the importance of a better characterization of SAg binding to their natural ligands that may allow the development of reagents to neutralize their action. The three-dimensional structure of the complex between a mouse TCR β chain (mVβ8.2) and staphylococcal enterotoxin G (SEG) at 2.0 Å resolution revealed a binding site that does not conserve the "hot spots" present in mVβ8.2-SEC2, mVβ8.2-SEC3, mVβ8.2-SEB, and mVβ8.2-SPEA complexes. Analysis of the mVβ8.2-SEG interface allowed us to explain the higher affinity of this complex compared with the others, which may account for the early activation of T-cells bearing mVβ8.2 by SEG. This mode of interaction between SEG and mVβ8.2 could be an adaptive advantage to bestow on the pathogen a faster rate of colonization of the host.
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Affiliation(s)
- Marisa M. Fernández
- From the Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956 4to P, 1113 Buenos Aires, Argentina
- the W. M. Keck Laboratory for Structural Biology, University of Maryland Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850
| | - Sangwoo Cho
- the W. M. Keck Laboratory for Structural Biology, University of Maryland Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850
| | - Mauricio C. De Marzi
- From the Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956 4to P, 1113 Buenos Aires, Argentina
- Departamento de Ciencias Básicas, Universidad Nacional de Luján, Ruta 5 y Constitución, 6700 Luján, Buenos Aires, Argentina, and
| | - Melissa C. Kerzic
- the W. M. Keck Laboratory for Structural Biology, University of Maryland Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850
| | - Howard Robinson
- Department of Biology, Brookhaven National Laboratory, Upton, New York 11973
| | - Roy A. Mariuzza
- the W. M. Keck Laboratory for Structural Biology, University of Maryland Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850
| | - Emilio L. Malchiodi
- From the Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956 4to P, 1113 Buenos Aires, Argentina
- the W. M. Keck Laboratory for Structural Biology, University of Maryland Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850
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14
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Saline M, Orekhov V, Lindkvist-Petersson K, Karlsson BG. Backbone resonance assignment of Staphylococcal Enterotoxin H. Biomol NMR Assign 2010; 4:1-4. [PMID: 19888679 DOI: 10.1007/s12104-009-9193-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Accepted: 10/08/2009] [Indexed: 05/28/2023]
Abstract
The staphylococcal enterotoxin H (SEH; 217 aa, 25 kD) belongs to a family of superantigens that cause a massive immune response upon simultaneous binding to the T cell receptor (TCR) and the major histocompatibility complex class II. The SEH-TCR interaction is weak and amenable to studies using NMR methodology. Essentially, 2 mg of U{(2)H, (13)C,(15)N}-labeled SEH was used for the complete sequential backbone assignment of SEH at 900 MHz. The protein secondary structure inferred from the chemical shift index (C(alpha) and C(beta)) is in very good agreement with the secondary structure elements of the X-ray structure.
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Affiliation(s)
- Maria Saline
- Swedish NMR Centre, University of Gothenburg, PO Box 465, 405 30 Gothenburg, Sweden
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15
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Solanki LS, Srivastava N, Singh S. Superantigens: a brief review with special emphasis on dermatologic diseases. Dermatol Online J 2008; 14:3. [PMID: 18700106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
MESH Headings
- Adult
- Animals
- Antigen Presentation
- Child
- Dermatitis, Atopic/immunology
- Dermatitis, Atopic/microbiology
- Female
- HLA-D Antigens/immunology
- Humans
- Immunization, Passive
- Immunosuppressive Agents/therapeutic use
- Lymphoma, T-Cell, Cutaneous/complications
- Lymphoma, T-Cell, Cutaneous/immunology
- Lymphoma, T-Cell, Cutaneous/microbiology
- Male
- Mucocutaneous Lymph Node Syndrome/immunology
- Psoriasis/immunology
- Receptors, Antigen, T-Cell/immunology
- Skin Diseases/immunology
- Staphylococcal Infections/immunology
- Superantigens/chemistry
- Superantigens/classification
- Superantigens/immunology
- T-Lymphocytes/immunology
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Affiliation(s)
- Lakhan Singh Solanki
- Department of Dermatology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
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16
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Saarinen S, Kato H, Uchiyama T, Miyoshi-Akiyama T, Papageorgiou AC. Crystal Structure of Streptococcus dysgalactiae-Derived Mitogen Reveals a Zinc-Binding Site and Alterations in TcR Binding. J Mol Biol 2007; 373:1089-97. [PMID: 17900619 DOI: 10.1016/j.jmb.2007.08.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Revised: 08/13/2007] [Accepted: 08/14/2007] [Indexed: 11/25/2022]
Abstract
Bacterial superantigens are protein toxins with an ability to cause serious diseases in humans by activating a large number of T cells. Streptococcus dysgalactiae-derived mitogen (SDM) is a novel superantigen that is distinct from other known superantigens based on phylogenetic analysis. The X-ray structure of SDM has been determined at 1.95 A resolution. SDM shares the same characteristic fold with other superantigens, but it shows a major structural difference due to the lack of the alpha5 helix between the beta10 and beta11 strands. A bound zinc ion was identified in the structure at the C-terminal domain of the molecule. SDM appears to bind to the major histocompatibility complex class II beta-chain through the zinc-binding site, as described by mutagenesis data and structural comparisons. T-cell binding instead shows a significant difference compared to other superantigens. The mutation of Asn11 (a conserved residue that is known to be significant for T-cell-receptor binding in other superantigens) and Lys15 to Ala did not cause any decrease in the mitogenic activity of SDM. This observation and the lack of the alpha5 helix suggest alterations in T-cell-receptor binding.
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Affiliation(s)
- Susanna Saarinen
- Turku Center for Biotechnology, University of Turku and Abo Akademi University, PO Box 123, Tykistökatu 6, BioCity, Turku 20521, Finland
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17
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Ramsland PA, Willoughby N, Trist HM, Farrugia W, Hogarth PM, Fraser JD, Wines BD. Structural basis for evasion of IgA immunity by Staphylococcus aureus revealed in the complex of SSL7 with Fc of human IgA1. Proc Natl Acad Sci U S A 2007; 104:15051-6. [PMID: 17848512 PMCID: PMC1986611 DOI: 10.1073/pnas.0706028104] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2007] [Indexed: 11/18/2022] Open
Abstract
Infection by Staphylococcus aureus can result in severe conditions such as septicemia, toxic shock, pneumonia, and endocarditis with antibiotic resistance and persistent nasal carriage in normal individuals being key drivers of the medical impact of this virulent pathogen. In both virulent infection and nasal colonization, S. aureus encounters the host immune system and produces a wide array of factors that frustrate host immunity. One in particular, the prototypical staphylococcal superantigen-like protein SSL7, potently binds IgA and C5, thereby inhibiting immune responses dependent on these major immune mediators. We report here the three-dimensional structure of the complex of SSL7 with Fc of human IgA1 at 3.2 A resolution. Two SSL7 molecules interact with the Fc (one per heavy chain) primarily at the junction between the Calpha2 and Calpha3 domains. The binding site on each IgA chain is extensive, with SSL7 shielding most of the lateral surface of the Calpha3 domain. However, the SSL7 molecules are positioned such that they should allow binding to secretory IgA. The key IgA residues interacting with SSL7 are also bound by the leukocyte IgA receptor, FcalphaRI (CD89), thereby explaining how SSL7 potently inhibits IgA-dependent cellular effector functions mediated by FcalphaRI, such as phagocytosis, degranulation, and respiratory burst. Thus, the ability of S. aureus to subvert IgA-mediated immunity is likely to facilitate survival in mucosal environments such as the nasal passage and may contribute to systemic infections.
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MESH Headings
- Antigens, CD/chemistry
- Antigens, CD/immunology
- Antigens, CD/metabolism
- Bacterial Proteins/chemistry
- Bacterial Proteins/immunology
- Bacterial Proteins/metabolism
- Binding Sites, Antibody
- Cells, Cultured
- Crystallography, X-Ray
- Genes, Bacterial/immunology
- Humans
- Immunoglobulin A/chemistry
- Immunoglobulin A/immunology
- Immunoglobulin A/metabolism
- Models, Molecular
- Mutagenesis
- Protein Conformation
- Receptors, Fc/chemistry
- Receptors, Fc/immunology
- Receptors, Fc/metabolism
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/metabolism
- Staphylococcus aureus/immunology
- Superantigens/chemistry
- Superantigens/immunology
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Affiliation(s)
- Paul A. Ramsland
- *The Inflammatory Disease and Structural Immunology Laboratories, The Burnet Institute, Austin Hospital, Studley Road, Heidelberg, Victoria 3084, Australia
- Department of Pathology, University of Melbourne, Melbourne, Victoria 3010, Australia; and
- Department of Immunology, Monash University, Melbourne, Victoria 3004, Australia
| | - Natasha Willoughby
- The Maurice Wilkins Centre and School of Medical Sciences, University of Auckland, Auckland 1020, New Zealand
| | - Halina M. Trist
- *The Inflammatory Disease and Structural Immunology Laboratories, The Burnet Institute, Austin Hospital, Studley Road, Heidelberg, Victoria 3084, Australia
| | - William Farrugia
- *The Inflammatory Disease and Structural Immunology Laboratories, The Burnet Institute, Austin Hospital, Studley Road, Heidelberg, Victoria 3084, Australia
| | - P. Mark Hogarth
- *The Inflammatory Disease and Structural Immunology Laboratories, The Burnet Institute, Austin Hospital, Studley Road, Heidelberg, Victoria 3084, Australia
- Department of Pathology, University of Melbourne, Melbourne, Victoria 3010, Australia; and
- Department of Immunology, Monash University, Melbourne, Victoria 3004, Australia
| | - John D. Fraser
- The Maurice Wilkins Centre and School of Medical Sciences, University of Auckland, Auckland 1020, New Zealand
| | - Bruce D. Wines
- *The Inflammatory Disease and Structural Immunology Laboratories, The Burnet Institute, Austin Hospital, Studley Road, Heidelberg, Victoria 3084, Australia
- Department of Pathology, University of Melbourne, Melbourne, Victoria 3010, Australia; and
- Department of Immunology, Monash University, Melbourne, Victoria 3004, Australia
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18
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Fluer FS. [Staphylococcal toxin of toxic shock syndrome]. Zh Mikrobiol Epidemiol Immunobiol 2007:106-114. [PMID: 18041127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Literature data on toxic shock syndrome staphylococcal toxin (TSST-1) are summarized; properties of Staphylococcus aureus strains producing TSST-1, nutrient media, and factors influencing on production of TSST-1 are reviewed. Physical and chemical properties of the toxin, its molecular characteristics, genetic regulation of its production, mechanism of action, and diseases which it causes are also discussed. Clinical and histologic signs of toxic shock syndrome (TSS), its diagnostic criteria, susceptibility of people to TSS, antigenic and serologic properties of the toxin, epidemiology of the infection caused by TSST-1-producing strains of staphylococci, methods of TSST-1 extraction and identification are described.
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19
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Pumphrey N, Vuidepot A, Jakobsen B, Forsberg G, Walse B, Lindkvist-Petersson K. Cutting Edge: Evidence of Direct TCR α-Chain Interaction with Superantigen. J Immunol 2007; 179:2700-4. [PMID: 17709482 DOI: 10.4049/jimmunol.179.5.2700] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Superantigens are known to activate a large number of T cells. The SAg is presented by MHC class II on the APC and its classical feature is that it recognizes the variable region of the beta-chain of the TCR. In this article, we report, by direct binding studies, that staphylococcal enterotoxin (SE) H (SEH), a bacterial SAg secreted by Staphylococcus aureus, instead recognizes the variable alpha-chain (TRAV27) of TCR. Furthermore, we show that different SAgs (e.g., SEH and SEA) can simultaneously bind to one TCR by binding the alpha-chain and the beta-chain, respectively. Theoretical three-dimensional models of the penta complexes are presented. Hence, these findings open up a new dimension of the biology of the staphylococcal enterotoxins.
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20
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Eppinger M, Rosovitz MJ, Fricke WF, Rasko DA, Kokorina G, Fayolle C, Lindler LE, Carniel E, Ravel J. The complete genome sequence of Yersinia pseudotuberculosis IP31758, the causative agent of Far East scarlet-like fever. PLoS Genet 2007; 3:e142. [PMID: 17784789 PMCID: PMC1959361 DOI: 10.1371/journal.pgen.0030142] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2007] [Accepted: 07/10/2007] [Indexed: 12/25/2022] Open
Abstract
The first reported Far East scarlet-like fever (FESLF) epidemic swept the Pacific coastal region of Russia in the late 1950s. Symptoms of the severe infection included erythematous skin rash and desquamation, exanthema, hyperhemic tongue, and a toxic shock syndrome. The term FESLF was coined for the infection because it shares clinical presentations with scarlet fever caused by group A streptococci. The causative agent was later identified as Yersinia pseudotuberculosis, although the range of morbidities was vastly different from classical pseudotuberculosis symptoms. To understand the origin and emergence of the peculiar clinical features of FESLF, we have sequenced the genome of the FESLF-causing strain Y. pseudotuberculosis IP31758 and compared it with that of another Y. pseudotuberculosis strain, IP32953, which causes classical gastrointestinal symptoms. The unique gene pool of Y pseudotuberculosis IP31758 accounts for more than 260 strain-specific genes and introduces individual physiological capabilities and virulence determinants, with a significant proportion horizontally acquired that likely originated from Enterobacteriaceae and other soil-dwelling bacteria that persist in the same ecological niche. The mobile genome pool includes two novel plasmids phylogenetically unrelated to all currently reported Yersinia plasmids. An icm/dot type IVB secretion system, shared only with the intracellular persisting pathogens of the order Legionellales, was found on the larger plasmid and could contribute to scarlatinoid fever symptoms in patients due to the introduction of immunomodulatory and immunosuppressive capabilities. We determined the common and unique traits resulting from genome evolution and speciation within the genus Yersinia and drew a more accurate species border between Y. pseudotuberculosis and Y. pestis. In contrast to the lack of genetic diversity observed in the evolutionary young descending Y. pestis lineage, the population genetics of Y. pseudotuberculosis is more heterogenous. Both Y. pseudotuberculosis strains IP31758 and the previously sequenced Y. pseudotuberculosis strain IP32953 have evolved by the acquisition of specific plasmids and by the horizontal acquisition and incorporation of different genetic information into the chromosome, which all together or independently seems to potentially impact the phenotypic adaptation of these two strains.
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Affiliation(s)
- Mark Eppinger
- J. Craig Venter Institute/The Institute for Genomic Research, Microbial Genomics, Rockville, Maryland, United States of America
| | - M. J Rosovitz
- J. Craig Venter Institute/The Institute for Genomic Research, Microbial Genomics, Rockville, Maryland, United States of America
| | - Wolfgang Florian Fricke
- J. Craig Venter Institute/The Institute for Genomic Research, Microbial Genomics, Rockville, Maryland, United States of America
| | - David A Rasko
- J. Craig Venter Institute/The Institute for Genomic Research, Microbial Genomics, Rockville, Maryland, United States of America
| | | | | | - Luther E Lindler
- Department of Defense, Global Emerging Infections Surveillance and Response System, Silver Spring, Maryland, United States of America
| | | | - Jacques Ravel
- J. Craig Venter Institute/The Institute for Genomic Research, Microbial Genomics, Rockville, Maryland, United States of America
- * To whom correspondence should be addressed. E-mail:
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21
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Günther S, Varma AK, Moza B, Kasper KJ, Wyatt AW, Zhu P, Rahman AKMNU, Li Y, Mariuzza RA, McCormick JK, Sundberg EJ. A novel loop domain in superantigens extends their T cell receptor recognition site. J Mol Biol 2007; 371:210-21. [PMID: 17560605 PMCID: PMC2949350 DOI: 10.1016/j.jmb.2007.05.038] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2007] [Revised: 05/10/2007] [Accepted: 05/11/2007] [Indexed: 10/23/2022]
Abstract
Superantigens (SAGs) interact with host immune receptors to induce a massive release of inflammatory cytokines that can lead to toxic shock syndrome and death. Bacterial SAGs can be classified into five distinct evolutionary groups. Group V SAGs are characterized by the alpha3-beta8 loop, a unique approximately 15 amino acid residue extension that is required for optimal T cell activation. Here, we report the X-ray crystal structures of the group V SAG staphylococcal enterotoxin K (SEK) alone and in complex with the TCR hVbeta5.1 domain. SEK adopts a unique TCR binding orientation relative to other SAG-TCR complexes, which results in the alpha3-beta8 loop contacting the apical loop of framework region 4, thereby extending the known TCR recognition site of SAGs. These interactions are absolutely required for TCR binding and T cell activation by SEK, and dictate the TCR Vbeta domain specificity of SEK and other group V SAGs.
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MESH Headings
- Bacterial Proteins/chemistry
- Bacterial Proteins/genetics
- Bacterial Proteins/immunology
- Crystallography, X-Ray
- Enterotoxins/chemistry
- Enterotoxins/immunology
- Humans
- Models, Molecular
- Protein Binding
- Protein Structure, Tertiary
- Receptors, Antigen, T-Cell, alpha-beta/chemistry
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Signal Transduction/physiology
- Staphylococcus aureus/immunology
- Superantigens/chemistry
- Superantigens/genetics
- Superantigens/immunology
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22
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Fernández MM, Bhattacharya S, De Marzi MC, Brown PH, Kerzic M, Schuck P, Mariuzza RA, Malchiodi EL. Superantigen natural affinity maturation revealed by the crystal structure of staphylococcal enterotoxin G and its binding to T-cell receptor Vβ8.2. Proteins 2007; 68:389-402. [PMID: 17427250 DOI: 10.1002/prot.21388] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The illnesses associated with bacterial superantigens (SAgs) such as food poisoning and toxic shock syndrome, as well as the emerging threat of purpura fulminans and community-associated methicillin-resistant S. aureus producer of SAgs, emphasize the importance of a better characterization of SAg binding to their natural ligands, which would allow the development of drugs or biological reagents able to neutralize their action. SAgs are toxins that bind major histocompatibility complex class II molecules (MHC-II) and T-cell receptors (TCR), in a nonconventional manner, inducing T-cell activation that leads to production of cytokines such as tumor necrosis factor and interleukin-2, which may result in acute toxic shock. Previously, we cloned and expressed a new natural variant of staphylococcal enterotoxin G (SEG) and evaluated its ability to stimulate in vivo murine T-cell subpopulations. We found an early, strong, and widespread stimulation of mouse Vbeta8.2 T-cells when compared with other SAgs member of the SEB subfamily. In search for the reason of the strong mitogenic potency, we determined the SEG crystal structure by X-ray crystallography to 2.2 A resolution and analyzed SEG binding to mVbeta8.2 and MHC-II. Calorimetry and SPR analysis showed that SEG has an affinity for mVbeta8.2 40 to 100-fold higher than that reported for other members of SEB subfamily, and the highest reported for a wild type SAg-TCR couple. We also found that mutations introduced in mVbeta8.2 to produce a high affinity mutant for other members of the SEB subfamily do not greatly affect binding to SEG. Crystallographic analysis and docking into mVbeta8.2 in complex with SEB, SEC3, and SPEA showed that the deletions and substitution of key amino acids remodeled the putative surface of the mVbeta8.2 binding site without affecting the binding to MHC-II. This results in a SAg with improved binding to its natural ligands, which may confer a possible evolutionary advantage for bacterial strains expressing SEG.
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Affiliation(s)
- Marisa M Fernández
- Instituto de Estudios de la Inmunidad Humoral, Laboratorio de Inmunología Estructural, CONICET, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
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23
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Zhao J, Hayashi T, Saarinen S, Papageorgiou AC, Kato H, Imanishi K, Kirikae T, Abe R, Uchiyama T, Miyoshi-Akiyama T. Cloning, expression, and characterization of the superantigen streptococcal pyrogenic exotoxin G from Streptococcus dysgalactiae. Infect Immun 2007; 75:1721-9. [PMID: 17283088 PMCID: PMC1865666 DOI: 10.1128/iai.01183-06] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We identified seven novel variants of streptococcal pyrogenic exotoxin G (SPEGG), a superantigen, in Streptococcus dysgalactiae subsp. dysgalactiae or equisimilis isolates from clinical cases of infection in humans and animals. Phylogenetic analysis of the SPEGG variants indicated two clades in the dendrogram: one composed of variants derived from the bacteria isolated from the humans and the other composed of variants from the bacteria isolated from the animals. Bovine peripheral blood mononuclear cells (PBMCs) were stimulated effectively by recombinant SPEGGs (rSPEGGs) expressed in Escherichia coli, while human PBMCs were not stimulated well by any of the rSPEGGs tested. SPEGGs selectively stimulated bovine T cells bearing Vbeta1,10 and Vbeta4. Bovine serum showed reactivity to the rSPEGG proteins. These results indicated that SPEGGs have properties as superantigens, and it is likely that SPEGGs play a pathogenic role in animals.
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Affiliation(s)
- Jizi Zhao
- Department of Infectious Diseases, Research Institute, International Medical Center of Japan, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan
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24
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Moza B, Varma AK, Buonpane RA, Zhu P, Herfst CA, Nicholson MJ, Wilbuer AK, Seth NP, Wucherpfennig KW, McCormick JK, Kranz DM, Sundberg EJ. Structural basis of T-cell specificity and activation by the bacterial superantigen TSST-1. EMBO J 2007; 26:1187-97. [PMID: 17268555 PMCID: PMC1852840 DOI: 10.1038/sj.emboj.7601531] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2006] [Accepted: 12/07/2006] [Indexed: 01/12/2023] Open
Abstract
Superantigens (SAGs) bind simultaneously to major histocompatibility complex (MHC) and T-cell receptor (TCR) molecules, resulting in the massive release of inflammatory cytokines that can lead to toxic shock syndrome (TSS) and death. A major causative agent of TSS is toxic shock syndrome toxin-1 (TSST-1), which is unique relative to other bacterial SAGs owing to its structural divergence and its stringent TCR specificity. Here, we report the crystal structure of TSST-1 in complex with an affinity-matured variant of its wild-type TCR ligand, human T-cell receptor beta chain variable domain 2.1. From this structure and a model of the wild-type complex, we show that TSST-1 engages TCR ligands in a markedly different way than do other SAGs. We provide a structural basis for the high TCR specificity of TSST-1 and present a model of the TSST-1-dependent MHC-SAG-TCR T-cell signaling complex that is structurally and energetically unique relative to those formed by other SAGs. Our data also suggest that protein plasticity plays an exceptionally significant role in this affinity maturation process that results in more than a 3000-fold increase in affinity.
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Affiliation(s)
- Beenu Moza
- Boston Biomedical Research Institute, Watertown, MA, USA
| | - Ashok K Varma
- Boston Biomedical Research Institute, Watertown, MA, USA
| | | | - Penny Zhu
- Boston Biomedical Research Institute, Watertown, MA, USA
| | - Christine A Herfst
- Department of Microbiology and Immunology, Lawson Health Research Institute, University of Western Ontario, London, Ontario, Canada
| | - Melissa J Nicholson
- Department of Cancer Immunology and AIDS, Dana Farber Cancer Research Institute, Harvard Medical School, Boston, MA, USA
| | - Anne-Kathrin Wilbuer
- Department of Cancer Immunology and AIDS, Dana Farber Cancer Research Institute, Harvard Medical School, Boston, MA, USA
- Program in Immunology, Harvard Medical School, Boston, MA, USA
| | - Nilufer P Seth
- Department of Cancer Immunology and AIDS, Dana Farber Cancer Research Institute, Harvard Medical School, Boston, MA, USA
| | - Kai W Wucherpfennig
- Department of Cancer Immunology and AIDS, Dana Farber Cancer Research Institute, Harvard Medical School, Boston, MA, USA
- Program in Immunology, Harvard Medical School, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - John K McCormick
- Department of Microbiology and Immunology, Lawson Health Research Institute, University of Western Ontario, London, Ontario, Canada
| | - David M Kranz
- Department of Biochemistry, University of Illinois, Urbana, IL, USA
| | - Eric J Sundberg
- Boston Biomedical Research Institute, Watertown, MA, USA
- Boston Biomedical Research Institute, 64 Grove Street, Watertown, MA 02472, USA. Tel.: +1 617 658 7882; Fax: +1 617 972 1761; E-mail:
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25
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Wang L, Zhao Y, Li Z, Guo Y, Jones LL, Kranz DM, Mourad W, Li H. Crystal structure of a complete ternary complex of TCR, superantigen and peptide-MHC. Nat Struct Mol Biol 2007; 14:169-71. [PMID: 17220897 PMCID: PMC3923521 DOI: 10.1038/nsmb1193] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2006] [Accepted: 12/21/2006] [Indexed: 11/09/2022]
Abstract
'Superantigens' (SAgs) trigger the massive activation of T cells by simultaneous interactions with MHC and TCR receptors, leading to human diseases. Here we present the first crystal structure, at 2.5-A resolution, of a complete ternary complex between a SAg and its two receptors, HLA-DR1/HA and TCR. The most striking finding is that the SAg Mycoplasma arthritidis mitogen, unlike others, has direct contacts not only with TCR Vbeta but with TCR Valpha.
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Affiliation(s)
- Limin Wang
- Wadsworth Center, New York State Department of Health, Albany, New York 12201, USA
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26
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Brouillard JNP, Günther S, Varma AK, Gryski I, Herfst CA, Rahman AKMNU, Leung DYM, Schlievert PM, Madrenas J, Sundberg EJ, McCormick JK. Crystal structure of the streptococcal superantigen SpeI and functional role of a novel loop domain in T cell activation by group V superantigens. J Mol Biol 2007; 367:925-34. [PMID: 17303163 DOI: 10.1016/j.jmb.2007.01.024] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2006] [Revised: 01/03/2007] [Accepted: 01/06/2007] [Indexed: 11/15/2022]
Abstract
Superantigens (SAgs) are potent microbial toxins that bind simultaneously to T cell receptors (TCRs) and class II major histocompatibility complex molecules, resulting in the activation and expansion of large T cell subsets and the onset of numerous human diseases. Within the bacterial SAg family, streptococcal pyrogenic exotoxin I (SpeI) has been classified as belonging to the group V SAg subclass, which are characterized by a unique, relatively conserved approximately 15 amino acid extension (amino acid residues 154 to 170 in SpeI; herein referred to as the alpha3-beta8 loop), absent in SAg groups I through IV. Here, we report the crystal structure of SpeI at 1.56 A resolution. Although the alpha3-beta8 loop in SpeI is several residues shorter than that of another group V SAg, staphylococcal enterotoxin serotype I, the C-terminal portions of these loops, which are located adjacent to the putative TCR binding site, are structurally similar. Mutagenesis and subsequent functional analysis of SpeI indicates that TCR beta-chains are likely engaged in a similar general orientation as other characterized SAgs. We show, however, that the alpha3-beta8 loop length, and the presence of key glycine residues, are necessary for optimal activation of T cells. Based on Vbeta-skewing analysis of human T cells activated with SpeI and structural models, we propose that the alpha3-beta8 loop is positioned to form productive intermolecular contacts with the TCR beta-chain, likely in framework region 3, and that these contacts are required for optimal TCR recognition by SpeI, and likely all other group V SAgs.
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Affiliation(s)
- Jean-Nicholas P Brouillard
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON, Canada N6A 5B8
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27
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Abstract
Yersinia pseudotuberculosis, a gastro-intestinal bacterium, produces three closely related T cell superantigens, YPMa, YPMb and YPMc, which have no significant sequence similarity to other proteins, let alone other bacterial superantigens. Y. pseudotuberculosisderived mitogen (YPM) has been shown to play a role in the pathogenesis of human and animal Y. pseudotuberculosis infection. The three-dimensional structure of YPMa, as determined by X-ray crystallography and nuclear magnetic resonance spectroscopy, exhibits a jelly roll fold, a structural motif not observed in other superantigens. YPMa is structurally most similar to virus capsid proteins and members of the tumour necrosis factor (TNF) superfamily. In the crystal structure, YPMa forms a trimer, another feature shared with virus capsid proteins and TNF superfamily proteins. However, in solution YPMa exists as a monomer, and any functional relevance of the trimer observed in the crystals is yet to be established. Structures of YPM bound to the T cell receptor and/or the major histocompatibility complex (MHC) are not yet available and mapping of existing mutagenesis data onto the three-dimensional structure of YPMa did not reveal potential T cell receptor/MHC binding sites. Knowledge of the structure will aid the design of functional studies aimed at further characterizing this superantigen.
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Affiliation(s)
- Roberta Donadini
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
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28
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Abstract
Superantigens (SAgs) are the most powerful T cell mitogens ever discovered. They activate the immune system by binding to the major histocompatibility complex (MHC) class II and T cell receptor molecules. One of the major producers of SAgs is Streptococcus pyogenes, or group A streptococcus (GAS). The recent completion of several GAS genome projects resulted in a sharp rise of novel streptococcal SAgs that were identified by database mining. Orthologue genes of several streptococcal SAgs have also been found in non-GAS, such as Streptococcus equi and Streptococcus disgalactiae. Crystal structure analyses have shown a common protein fold for all streptococcal SAgs analyzed thus far. Furthermore, cocrystal structures of SAgs complexed with MHC class II and T cell receptor Beta-chains, respectively, have provided further insight into the molecular interactions of these toxins with their host cell receptors. This chapter will also discuss the potential involvement of SAgs in severe GAS disease, in particular the highly lethal streptococcal toxic shock syndrome.
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Affiliation(s)
- Thomas Proft
- Department of Molecular Medicine and Pathology, School of Medicine, University of Auckland, Auckland, New Zealand
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29
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Abstract
Bacterial superantigens (SAgs) constitute a large family of bacterial toxins that share the capacity to induce massive activation of the human immune system. Such a feature is based on the ability of these toxins to activate T cells that express Beta-chains of the T cell antigen receptor (TCR) containing variable regions (V) coded by specific families of VBeta genes. In addition, bacterial SAgs bypass the need for processing by antigen-presenting cells by directly binding to major histocompatibility complex class II molecules on the surface of these cells. Emerging work indicates that bacterial SAgs utilize not only the canonical pathways of TCR-mediated T cell activation but also other pathways. Here, we review the structural information on recognition of bacterial SAgs by T cells, the TCR signalling induced by this recognition event, and the effector functions that this recognition triggers. We analyze experimental evidence suggesting the existence of alternative receptors and coreceptors for bacterial SAgs, and outline future challenges in the research with these toxins.
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Affiliation(s)
- Clara Bueno
- FOCIS Centre for Clinical Immunology and Immunotherapeutics, Ont., Canada
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30
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Abstract
Mouse mammary tumor virus (MMTV) has developed a strategy of exploitation of the immune response. It infects dendritic cells and B cells and requires this infection to establish an efficient chronic infection. This allows transmission of infection to the mammary gland, production in milk and infection of the next generation via lactation. The elaborate strategy developed by MMTV utilizes several key elements of the normal immune response. Starting with the infection and activation of dendritic cells and B cells leading to the expression of a viral superantigen followed by professional superantigen-mediated priming of naive polyclonal T cells by dendritic cells and induction of superantigen-mediated T cell B cell collaboration results in long-lasting germinal center formation and production of long-lived B cells that can later carry the virus to the mammary gland epithelium. Later in life it can induce transformation of mammary gland epithelium by integrating close to proto-oncogenes leading to their overexpression. Genes encoding proteins of the Wnt-pathway are preferential targets. This review will put these effects in the context of a normal immune response and summarize important facts on MMTV biology.
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Affiliation(s)
- Hans Acha-Orbea
- Department of Biochemistry, University of Lausanne, Ch. des Boveresses 155, CH-1066 Epalinges, Switzerland.
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31
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Li H, Zhao Y, Guo Y, Li Z, Eisele L, Mourad W. Zinc induces dimerization of the class II major histocompatibility complex molecule that leads to cooperative binding to a superantigen. J Biol Chem 2006; 282:5991-6000. [PMID: 17166841 PMCID: PMC3924565 DOI: 10.1074/jbc.m608482200] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Dimerization of class II major histocompatibility complex (MHC) plays an important role in the MHC biological function. Mycoplasma arthritidis-derived mitogen (MAM) is a superantigen that can activate large fractions of T cells bearing specific T cell receptor Vbeta elements. Here we have used structural, sedimentation, and surface plasmon resonance detection approaches to investigate the molecular interactions between MAM and the class II MHC molecule HLA-DR1 in the context of a hemagglutinin peptide-(306-318) (HA). Our results revealed that zinc ion can efficiently induce the dimerization of the HLA-DR1/HA complex. Because the crystal structure of the MAM/HLA-DR1/hemagglutinin complex in the presence of EDTA is nearly identical to the structure of the complex crystallized in the presence of zinc ion, Zn(2+) is evidently not directly involved in the binding between MAM and HLA-DR1. Sedimentation and surface plasmon resonance studies further revealed that MAM binds the HLA-DR1/HA complex with high affinity in a 1:1 stoichiometry, in the absence of Zn(2+). However, in the presence of Zn(2+), a dimerized MAM/HLA-DR1/HA complex can arise through the Zn(2+)-induced DR1 dimer. In the presence of Zn(2+), cooperative binding of MAM to the DR1 dimer was also observed.
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Affiliation(s)
- Hongmin Li
- Wadsworth Center, New York State Department of Health, University of Albany, State University of New York, Albany, New York 12208, USA.
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32
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Nooh MM, Aziz RK, Kotb M, Eroshkin A, Chuang WJ, Proft T, Kansal R. Streptococcal mitogenic exotoxin, SmeZ, is the most susceptible M1T1 streptococcal superantigen to degradation by the streptococcal cysteine protease, SpeB. J Biol Chem 2006; 281:35281-8. [PMID: 16980693 DOI: 10.1074/jbc.m605544200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Superantigens (SAgs) play an important role in the pathogenesis of severe invasive infections caused by Group A Streptococcus (GAS). We had shown earlier that the expression of streptococcal cysteine protease SpeB results in partial loss of the immune-stimulating activity of the native secreted GAS SAgs, namely the streptococcal pyrogenic exotoxins produced by the globally disseminated M1T1 GAS strain, associated with invasive infections worldwide. In this study, we examined the susceptibility of each of the M1T1 recombinant SAgs to degradation by rSpeB. Whereas SmeZ was degraded completely within 30 min of incubation with rSpeB, SpeG, and SpeA were more resistant and SpeJ was completely unaffected by the proteolytic effects of this protease. Proteomic analyses demonstrated that the order of susceptibility of the M1T1 SAgs to SpeB proteolysis is unaltered when they are present in a mixture that reflects their native physiological status. As expected, the degradation of SmeZ abolished its immune stimulatory activity. In silico sequence disorder and structural analyses revealed that SmeZ, unlike the three other structurally related SAgs, possesses a putative SpeB cleavage site within an area of the protein likely to be exposed to the surface. The study provides evidence for the effect of subtle structural differences between highly similar SAgs on their biological activity.
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Affiliation(s)
- Mohammed M Nooh
- Department of Molecular Sciences, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
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33
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Fernández MM, Guan R, Swaminathan CP, Malchiodi EL, Mariuzza RA. Crystal structure of staphylococcal enterotoxin I (SEI) in complex with a human major histocompatibility complex class II molecule. J Biol Chem 2006; 281:25356-64. [PMID: 16829512 PMCID: PMC2730046 DOI: 10.1074/jbc.m603969200] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Superantigens are bacterial or viral proteins that elicit massive T cell activation through simultaneous binding to major histocompatibility complex (MHC) class II and T cell receptors. This activation results in uncontrolled release of inflammatory cytokines, causing toxic shock. A remarkable property of superantigens, which distinguishes them from T cell receptors, is their ability to interact with multiple MHC class II alleles independently of MHC-bound peptide. Previous crystallographic studies have shown that staphylococcal and streptococcal superantigens belonging to the zinc family bind to a high affinity site on the class II beta-chain. However, the basis for promiscuous MHC recognition by zinc-dependent superantigens is not obvious, because the beta-chain is polymorphic and the MHC-bound peptide forms part of the binding interface. To understand how zinc-dependent superantigens recognize MHC, we determined the crystal structure, at 2.0 A resolution, of staphylococcal enterotoxin I bound to the human class II molecule HLA-DR1 bearing a peptide from influenza hemagglutinin. Interactions between the superantigen and DR1 beta-chain are mediated by a zinc ion, and 22% of the buried surface of peptide.MHC is contributed by the peptide. Comparison of the staphylococcal enterotoxin I.peptide.DR1 structure with ones determined previously revealed that zinc-dependent superantigens achieve promiscuous binding to MHC by targeting conservatively substituted residues of the polymorphic beta-chain. Additionally, these superantigens circumvent peptide specificity by engaging MHC-bound peptides at their conformationally conserved N-terminal regions while minimizing sequence-specific interactions with peptide residues to enhance cross-reactivity.
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Affiliation(s)
- Marisa M Fernández
- Instituto de Estudios de la Inmunidad Humoral, Laboratorio de Inmunología Estructural, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
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34
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Vázquez García RE, Hernández Bautista V, Espinosa Padilla S. [Superantigens and toxic shock syndrome. A report of three cases treated with intravenous gammaglobulin]. Rev Alerg Mex 2006; 53:183-8. [PMID: 17357565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023] Open
Abstract
The superantigens cause a massive polyclonal activation of T-cells, producing an immense liberation of proinflamatory cytokines, which induces the clinical data of toxic shock syndrome. In international studies the administration of polyclonal intravenous gammaglobulin has been observed to diminish the mortality 50 to 20%. But at the present it has not been reported in Mexico the clinical effectiveness of this therapeutic modality in toxic shock syndrome. We report three cases of toxic shock syndrome treated with gammaglobulin intravenous, and we describe their favorable clinical evolution.
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35
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Timchenko NF. [Yersinia pseudotuberculosis toxins]. Zh Mikrobiol Epidemiol Immunobiol 2006:83-9. [PMID: 17163146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The review of publications about protein toxins Y. pseudotuberculosis are presented. It includes the main data obtained by domestic and foreign investigators as well as the results of our own elaboration in the study of Y. pseudotuberculosis protein toxins. The guestions of isolation, purification, characterization of physico-chemical and biological properties, the mechanism action and role of toxins on pathogenesis of infection were discussed.
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36
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Moza B, Buonpane RA, Zhu P, Herfst CA, Rahman AKMNU, McCormick JK, Kranz DM, Sundberg EJ. Long-range cooperative binding effects in a T cell receptor variable domain. Proc Natl Acad Sci U S A 2006; 103:9867-72. [PMID: 16788072 PMCID: PMC1502545 DOI: 10.1073/pnas.0600220103] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Although cellular processes depend on protein-protein interactions, our understanding of molecular recognition between proteins remains far from comprehensive. Protein-protein interfaces are structural and energetic mosaics in which a subset of interfacial residues, called hot spots, contributes disproportionately to the affinity of the complex. These hot-spot residues can be further clustered into hot regions. It has been proposed that binding energetics between residues within a hot region are cooperative, whereas those between hot regions are strictly additive. If this idea held true for all protein-protein interactions, then energetically significant long-range conformational effects would be unlikely to occur. In the present study, we show cooperative binding energetics between distinct hot regions that are separated by >20 A. Using combinatorial mutagenesis and surface plasmon resonance binding analysis to dissect additivity and cooperativity in a complex formed between a variable domain of a T cell receptor and a bacterial superantigen, we find that combinations of mutations from each of two hot regions exhibited significant cooperative energetics. Their connecting sequence is composed primarily of a single beta-strand of the T cell receptor variable Ig domain, which has been observed to undergo a strand-switching event and does not form an integral part of the stabilizing core of this Ig domain. We propose that these cooperative effects are propagated through a dynamic structural network. Cooperativity between hot regions has significant implications for the prediction and inhibition of protein-protein interactions.
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Affiliation(s)
- Beenu Moza
- *Boston Biomedical Research Institute, Watertown, MA 02472
| | - Rebecca A. Buonpane
- Department of Biochemistry, University of Illinois at Urbana–Champaign, Urbana, IL 61801; and
| | - Penny Zhu
- *Boston Biomedical Research Institute, Watertown, MA 02472
| | - Christine A. Herfst
- Lawson Health Research Institute and Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada N6A 4V2
| | - A. K. M. Nur-ur Rahman
- Lawson Health Research Institute and Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada N6A 4V2
| | - John K. McCormick
- Lawson Health Research Institute and Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada N6A 4V2
| | - David M. Kranz
- Department of Biochemistry, University of Illinois at Urbana–Champaign, Urbana, IL 61801; and
| | - Eric J. Sundberg
- *Boston Biomedical Research Institute, Watertown, MA 02472
- To whom correspondence should be addressed. E-mail:
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37
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Li H, Zhao Y, Guo Y, VanVranken SJ, Li Z, Eisele L, Mourad W. Mutagenesis, biochemical, and biophysical characterization of Mycoplasma arthritidis-derived mitogen. Mol Immunol 2006; 44:763-73. [PMID: 16753217 PMCID: PMC3923304 DOI: 10.1016/j.molimm.2006.04.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2006] [Accepted: 04/11/2006] [Indexed: 02/02/2023]
Abstract
Mycoplasma arthritidis-derived mitogen (MAM) is a superantigen (SAg) that can activate large fractions of T cells bearing particular TCR Vbeta elements. Here we report the mutagenesis, biochemical and biophysical studies on the dimerization of MAM in solution. Our studies showed that although MAM mainly exists as a monomer in solution, a small percentage of MAM molecules form homodimer at high protein concentration, regardless of the presence of Zn2+. A distinct peak corresponding to a MAM homodimer was detected in the presence of EDTA, using both chemical cross-linking and analytical ultracentrifugation methods. Further mutagenesis studies revealed that single mutation of residues at the interface of the crystallographic dimer of MAM does not significantly affect the dimerization of MAM in solution. Circular dichroism (CD) analysis indicated that addition of Zn2+ does not induce conformational changes of MAM from its apo-state. Thermal denaturation experiments indicated that addition of Zn2+ to MAM solution resulted in a decrease of melting point (Tm), whereas addition of EDTA did not affect the Tm of MAM. These results imply that there is no defined Zn2+-binding site on MAM.
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Affiliation(s)
- Hongmin Li
- Wadsworth Center, New York State Department of Health, Empire State Plaza, PO Box 509, Albany, NY 12201-0509, United States
- Department of Biomedical Sciences, School of Public Health, University at Albany, State University of New York, Empire State Plaza, PO Box 509, Albany, NY 12201-0509, United States
- Corresponding author. Tel.: +1 518 486 9154; fax: +1 518 474 7992. (H. Li)
| | - Yiwei Zhao
- Wadsworth Center, New York State Department of Health, Empire State Plaza, PO Box 509, Albany, NY 12201-0509, United States
| | - Yi Guo
- Wadsworth Center, New York State Department of Health, Empire State Plaza, PO Box 509, Albany, NY 12201-0509, United States
| | - Sandra J. VanVranken
- Wadsworth Center, New York State Department of Health, Empire State Plaza, PO Box 509, Albany, NY 12201-0509, United States
| | - Zhong Li
- Wadsworth Center, New York State Department of Health, Empire State Plaza, PO Box 509, Albany, NY 12201-0509, United States
| | - Leslie Eisele
- Wadsworth Center, New York State Department of Health, Empire State Plaza, PO Box 509, Albany, NY 12201-0509, United States
| | - Walid Mourad
- Université de Montreal, CHUM, Campus St-Luc, PEA, 264, Boul. René Lévesque Est, Bureau 313, Montréal, Qué. H2X 1P1, Canada
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38
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Abstract
Studies of microbial superantigens that target large clonal sets of B cells through conserved antigen-receptor-variable-region sites are providing new insights into the mechanisms of B-cell activation-induced cell death. These investigations have shown differences between the clonal regulation of follicular B cells (B2 cells) and the innate-like marginal-zone B cells and B1 cells, and have also shown how B-cell superantigens can affect specialized host defences against infection. Agents designed to emulate the properties of B-cell superantigens might also provide new approaches for the treatment of B-cell-mediated autoimmune and neoplastic diseases.
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Affiliation(s)
- Gregg J Silverman
- Rheumatic Disease Core Center, Department of Medicine, University of California, San Diego, La Jolla, California 92093-0663, USA.
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39
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Guo Y, Li Z, Van Vranken SJ, Li H. A single point mutation changes the crystallization behavior of Mycoplasma arthritidis-derived mitogen. Acta Crystallogr Sect F Struct Biol Cryst Commun 2006; 62:238-41. [PMID: 16511311 PMCID: PMC2197180 DOI: 10.1107/s1744309106003691] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2006] [Accepted: 01/30/2006] [Indexed: 11/10/2022]
Abstract
Mycoplasma arthritidis-derived mitogen (MAM) functions as a conventional superantigen (SAg). Although recombinant MAM has been crystallized by the hanging-drop vapour-diffusion method, the crystals diffracted poorly to only 5.0 A resolution, with large unit-cell parameters a = 163.8, b = 93.0, c = 210.9 A, beta = 93.7 degrees in the monoclinic space group P2(1). Unit-cell content analysis revealed that as many as 24 molecules could be present in the asymmetric unit. Systematic alanine mutagenesis was applied in order to search for mutants that give crystals of better quality. Two mutants, L50A and K201A, were crystallized under the same conditions as wild-type MAM (MAMwt). Crystals of the L50A mutant are isomorphous with those of MAMwt, while a new crystal form was obtained for the K201 mutant, belonging to the cubic space group P4(1)32 with unit-cell parameters a = b = c = 181.9 A. Diffraction data were collected to 3.6 and 2.8 A resolution from crystals of the MAM L50A and K201A mutants, respectively. Molecular-replacement calculations suggest the presence of two molecules in the asymmetric unit for the MAM K201A mutant crystal, resulting in a VM of 5.0 A Da(-1) and a solvent content of 75%. An interpretable electron-density map for the MAM K201A mutant crystal was produced using the molecular-replacement method.
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Affiliation(s)
- Yi Guo
- Wadsworth Center, New York State Department of Health, Empire State Plaza, PO Box 509, Albany, New York 12201-0509, USA
| | - Zhong Li
- Wadsworth Center, New York State Department of Health, Empire State Plaza, PO Box 509, Albany, New York 12201-0509, USA
| | - Sandra J. Van Vranken
- Wadsworth Center, New York State Department of Health, Empire State Plaza, PO Box 509, Albany, New York 12201-0509, USA
| | - Hongmin Li
- Wadsworth Center, New York State Department of Health, Empire State Plaza, PO Box 509, Albany, New York 12201-0509, USA
- Department of Biomedical Sciences, School of Public Health, University at Albany, State University of New York, Empire State Plaza, PO Box 509, Albany, New York 12201-0509, USA
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40
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Papageorgiou AC, Saarinen S, Ramirez-Bartutis R, Kato H, Uchiyama T, Kirikae T, Miyoshi-Akiyama T. Expression, purification and crystallization of Streptococcus dysgalactiae-derived mitogen. Acta Crystallogr Sect F Struct Biol Cryst Commun 2006; 62:242-4. [PMID: 16511312 PMCID: PMC2197169 DOI: 10.1107/s1744309106003678] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2006] [Accepted: 01/30/2006] [Indexed: 11/10/2022]
Abstract
Superantigens are bacterial or viral toxins with potent immunostimulatory properties. Streptococcus dysgalactiae-derived mitogen, a 25 kDa protein, is a recently discovered superantigen isolated from S. dysgalactiae culture supernatant. Sequence considerations suggest that it belongs to a new superantigen family distinct from other superantigens. The protein was expressed in Escherichia coli cells and purified to homogeneity. Crystals were grown at pH 4.2-4.4 in the presence of 18-20%(w/v) PEG 3350 and 0.4 M lithium nitrate. A complete data set to 2.4 A resolution was collected from a single crystal at liquid-nitrogen temperatures using synchrotron radiation. The crystals belong to space group P3/P3(1)/P3(2), with unit-cell parameters a = b = 52.7, c = 62.4 A, gamma = 120 degrees and one molecule in the crystallographic asymmetric unit.
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41
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Fernández MM, De Marzi MC, Berguer P, Burzyn D, Langley RJ, Piazzon I, Mariuzza RA, Malchiodi EL. Binding of natural variants of staphylococcal superantigens SEG and SEI to TCR and MHC class II molecule. Mol Immunol 2006; 43:927-38. [PMID: 16023209 DOI: 10.1016/j.molimm.2005.06.029] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2005] [Indexed: 11/17/2022]
Abstract
SEG and SEI are staphylococcal superantigens (SAgs) identified recently that belong to the egc operon and whose genes are in tandem orientation. Only a few allelic variants of SEG and SEI have been reported. Here we analyzed four Staphylococcus aureus strains with genotypic variation in both SAgs. However, both SAgs retain key residues in their putative TCR and MHC binding sites and, accordingly, their superantigenic properties. Thus, SEI significantly stimulates mouse T-cells bearing Vbeta3, 5 and 13, while SEG stimulates Vbeta7 and 9 in the draining node when inoculated in the footpad. As another member of the SEB subfamily, SEG also stimulates mouse Vbeta8.1+2. However, the increase in Vbeta8.1+2 T-cells observed at day 2 after inoculation reverts to normal values at day 4, whereas it remains high at day 4 following inoculation with SEC3 or SSA. T-cell stimulation assays in the mouse and analysis of the putative Vbeta8.2 binding site on SEG, which includes three non-conserved residues, suggest a possibly unique interaction between Vbeta8.2 and SEG. We also analyzed biochemical and biophysical characteristics of SEI and SEG binding to their cognate human beta chains by surface plasmon resonance, and binding to the HLA-DR1 MHC class II molecule by gel filtration. SEI binds human Vbeta5.2 and Vbeta1 with apparent K(D)'s of 23 and 118 microM, respectively; SEG binds Vbeta13.6 with a K(D) of 5 microM. As suggested by sequence homology, SEI requires Zn2+ for strong binding to DR1, which goes undetected in the presence of EDTA. SEG and SEI have characteristics such as co-expression, different interaction with MHC class II and stimulation of completely different subsets of human and mouse T-cells, which indicate complementary superantigenic activity and suggest an important advantage to staphylococcal strains in producing them both.
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Affiliation(s)
- Marisa M Fernández
- Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral (IDEHU), CONICET, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
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42
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Buonpane RA, Moza B, Sundberg EJ, Kranz DM. Characterization of T cell receptors engineered for high affinity against toxic shock syndrome toxin-1. J Mol Biol 2005; 353:308-21. [PMID: 16171815 DOI: 10.1016/j.jmb.2005.08.041] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2005] [Revised: 08/16/2005] [Accepted: 08/18/2005] [Indexed: 11/26/2022]
Abstract
Superantigens, including bacterial enterotoxins, are a family of proteins that bind simultaneously to MHC class II molecules and the Vbeta regions of T cell receptors. This cross-linking results in the activation of a large population of T cells that release massive amounts of inflammatory cytokines, ultimately causing a condition known as toxic shock syndrome. The staphylococcal superantigen toxic shock syndrome toxin-1 (TSST-1) is a causative agent of this disease, but its structure in complex with the cognate T cell receptor (human Vbeta2.1) has not been determined. To understand the molecular details of the interaction and to develop high affinity antagonists to TSST-1, we used directed evolution to generate a panel of high affinity receptors for TSST-1. Yeast display libraries of random and site-directed hVbeta2.1 mutants were selected for improved domain stability and for higher affinity binding to TSST-1. Stability mutations allowed the individual Vbeta domains to be expressed in a bacterial expression system. Affinity mutations were generated in CDR2 and FR3 residues, yielding improvements in affinity of greater than 10,000-fold (a K(D) value of 180 pmol). Alanine scanning mutagenesis of hVbeta2.1 wild-type and mutated residues allowed us to generate a map of the binding site for TSST-1 and to construct a docking model for the hVbeta2.1-TSST-1 complex. Our experiments suggest that the energetic importance of a single hVbeta2.1 wild-type residue likely accounts for the restriction of TSST-1 specificity to only this human Vbeta region. The high affinity mutants described here thus provide critical insight into the molecular basis of TSST-1 specificity and serve as potential leads toward the development of therapeutic agents for superantigen-mediated disease.
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MESH Headings
- Alanine/metabolism
- Amino Acid Sequence
- Bacterial Toxins/chemistry
- Bacterial Toxins/immunology
- Bacterial Toxins/metabolism
- Enterotoxins/chemistry
- Enterotoxins/immunology
- Enterotoxins/metabolism
- Humans
- Models, Molecular
- Molecular Sequence Data
- Mutagenesis, Site-Directed
- Protein Binding
- Protein Conformation
- Receptors, Antigen, T-Cell, alpha-beta/chemistry
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Sequence Alignment
- Superantigens/chemistry
- Superantigens/immunology
- Superantigens/metabolism
- Surface Plasmon Resonance
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Affiliation(s)
- Rebecca A Buonpane
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA
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43
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Omoe K, Imanishi K, Hu DL, Kato H, Fugane Y, Abe Y, Hamaoka S, Watanabe Y, Nakane A, Uchiyama T, Shinagawa K. Characterization of novel staphylococcal enterotoxin-like toxin type P. Infect Immun 2005; 73:5540-6. [PMID: 16113270 PMCID: PMC1231067 DOI: 10.1128/iai.73.9.5540-5546.2005] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We investigated the biological properties of a novel staphylococcal enterotoxin (SE)-like toxin type P (SElP). SElP induced a substantial proliferative response and the production of cytokines interleukin-2, gamma interferon, tumor necrosis factor alpha, and interleukin-4 from human T cells when administered at a concentration of 0.4 pM (0.01 ng/ml) or more. The expression of major histocompatibility complex class II molecules on accessory cells was required for T-cell stimulation by SElP. SElP selectively stimulated a vast number of human T cells bearing receptors Vbeta 5.1, 6, 8, 16, 18, and 21.3. These results indicated that SElP acts as a superantigen. SElP proved to be emetic in the house musk shrew emetic assay, although at a relatively high dose (50 to 150 mug/animal). A quantitative assay of SElP production with 30 Staphylococcus aureus strains harboring selp showed that 60% of these strains produced significant amounts of SElP in vitro. All 10 strains carrying seb and selp produced SEB but not SElP, suggesting the inactivation of the selp locus in S. aureus strains with a particular se gene constitution.
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Affiliation(s)
- Katsuhiko Omoe
- Department of Veterinary Microbiology, Faculty of Agriculture, Iwate University, Ueda 3-18-8, Morioka, Iwate 020-8550, Japan.
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44
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Haas PJ, de Haas CJC, Poppelier MJJC, van Kessel KPM, van Strijp JAG, Dijkstra K, Scheek RM, Fan H, Kruijtzer JAW, Liskamp RMJ, Kemmink J. The structure of the C5a receptor-blocking domain of chemotaxis inhibitory protein of Staphylococcus aureus is related to a group of immune evasive molecules. J Mol Biol 2005; 353:859-72. [PMID: 16213522 DOI: 10.1016/j.jmb.2005.09.014] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2005] [Revised: 09/06/2005] [Accepted: 09/07/2005] [Indexed: 12/21/2022]
Abstract
The chemotaxis inhibitory protein of Staphylococcus aureus (CHIPS) is a 121 residue excreted virulence factor. It acts by binding the C5a- (C5aR) and formylated peptide receptor (FPR) and thereby blocks specific phagocyte responses. Here, we report the solution structure of a CHIPS fragment consisting of residues 31-121 (CHIPS31-121). CHIPS31-121 has the same activity in blocking the C5aR compared to full-length CHIPS, but completely lacks FPR antagonism. CHIPS31-121 has a compact fold comprising an alpha-helix (residues 38-51) packed onto a four-stranded anti-parallel beta-sheet. Strands beta2 and beta3 are joined by a long loop with a relatively well-defined conformation. Comparison of CHIPS31-121 with known structures reveals striking homology with the C-terminal domain of staphylococcal superantigen-like proteins (SSLs) 5 and 7, and the staphyloccocal and streptococcal superantigens TSST-1 and SPE-C. Also, the recently reported structures of several domains of the staphylococcal extracellullar adherence protein (EAP) show a high degree of structural similarity with CHIPS. Most of the conserved residues in CHIPS and its structural homologues are present in the alpha-helix. A conserved arginine residue (R46 in CHIPS) appears to be involved in preservation of the structure. Site-directed mutagenesis of all positively charged residues in CHIPS31-121 reveals a major involvement of arginine 44 and lysine 95 in C5aR antagonism. The structure of CHIPS31-121 will be vital in the further unraveling of its precise mechanism of action. Its structural homology to S.aureus SSLs, superantigens, and EAP might help the design of future experiments towards an understanding of the relationship between structure and function of these proteins.
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Affiliation(s)
- Pieter-Jan Haas
- Eijkman-Winkler Institute, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
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45
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Krakauer T. Chemotherapeutics targeting immune activation by staphylococcal superantigens. Med Sci Monit 2005; 11:RA290-5. [PMID: 16127375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2005] [Accepted: 06/16/2005] [Indexed: 05/04/2023] Open
Abstract
Staphylococcal enterotoxin B (SEB) and related superantigenic toxins are potent activators of the immune system and cause a variety of diseases in humans, ranging from food poisoning to toxic shock. These toxins bind to both MHC class II molecules and specific Vbeta regions of T cell receptors (TCR), resulting in the activation of both monocytes/macrophages and T lymphocytes. The interactions of these toxins with host cells lead to excessive production of proinflammatory cytokines and T cell proliferation, causing clinical symptoms that include fever, hypotension and shock. Different domains of SEB contributing to MHC class II or TCR interactions have been mapped and defined by mutagenesis, crystallography and other biochemical techniques. This review summarizes the in vitro and in vivo effects of staphylococcal superantigens, and the therapeutic agents to mitigate their toxic effects. Potential targets to prevent the toxic effects of bacterial superantigens include blocking the interaction of SEs with MHC or TCR, or other costimulatory molecules; inhibition of signal transduction pathways used by these superantigens; inhibition of cytokine and chemokine production; and inhibition of the downstream signaling pathways used by proinflammatory cytokines and chemokines. Early blockade of these targets proves to be useful in vitro and in vivo testing of therapeutics against SEB-induced toxic shock will also be reviewed.
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Affiliation(s)
- Teresa Krakauer
- Department of Immunology, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, MD 21702-5011, USA.
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46
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Wang JL, Zheng YL, Ma R, Wang BL, Guo AG, Jiang YQ. Disulfide-stabilized single-chain antibody-targeted superantigen: Construction of a prokaryotic expression system and its functional analysis. World J Gastroenterol 2005; 11:4899-903. [PMID: 16097068 PMCID: PMC4398746 DOI: 10.3748/wjg.v11.i31.4899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To construct the expression vector of B3 (scdsFv)-SEA (D227A) and to identify its binding and cytotoxic ability to B3 antigen positive carcinoma cell lines.
METHODS: This fusion protein was produced by a bacterial expression system in this study. It was expressed mainly in the inclusion body. The gene product was solubilized by guanidine hydrochloride, refolded by conventional dilution method, and purified using SP-sepharose cation chromatography.
RESULTS: The expression vector B3 (scdsFv)-SEA-PET was constructed, the expression product existed mainly in the inclusion body, the refolding product retained the binding ability of the single-chain antibody and had cytotoxic effect on HT-29 colon carcinoma cells. The stability assay showed that the resulting protein was stable at 37 °C.
CONCLUSION: This genetically engineered B3 (scdsFv)-SEA fusion protein has bifunction of tumor targeting and tumor cell killing and shows its promises as an effective reagent for tumor-targeted immunotherapy.
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Affiliation(s)
- Jian-Li Wang
- Department of Life Science, Northwest Sci-Tech University of Agriculture and Forestry, No. 22 Xi-nong Road, Yangling 712100, Shaanxi Province, China
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47
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Hao HJ, Jiang YQ, Zheng YL, Ma R, Yu DW. Improved stability and yield of Fv targeted superantigen by introducing both linker and disulfide bond into the targeting moiety. Biochimie 2005; 87:661-7. [PMID: 15927340 DOI: 10.1016/j.biochi.2005.04.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2004] [Revised: 03/07/2005] [Accepted: 04/11/2005] [Indexed: 11/17/2022]
Abstract
Bacterial superantigens (SAg) are the most potent activators of human T lymphocytes and recombinant immunotoxin using bacterial SAg shows promising clinical values. To engineer superantigen for immunotherapy of hepatocellular carcinoma, we genetically fused the superantigen staphylococcus enterotoxin A (SEA(D(227)A)) to the single-chain disulfide-stabilized Fv (scdsFv) of anti-hepatoma monoclonal antibody HAb25 through a short peptide GGGSGGS. We expressed this recombinant protein in Escherichia coli and extract it from inclusion bodies. We found purified scdsFv-targeted SAg contains equivalent binding affinity with disulfide-stabilized Fv (dsFv) targeted SAg and single-chain Fvs (scFv) targeted SAg, but more stable and more suitable for large scale production. The MTS(3-(4,5-dimethylthiazole-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazoliu m, inner salt) assay shows that the scdsFv-targeted SAg also shares the ability to activate a large number of T lymphocytes and has cytotoxic activity on human hepatoma cell line SMMC-7721. Therefore, this novel generation of recombinant immunotoxins using scdsFv has a high potential in hepato cancer treatment and the same strategy may also be applied to other cancer treatments.
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Affiliation(s)
- Huai-Jie Hao
- State Key Laboratory of Pathogen and Biosecurity, The Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences, No. 20 Dongda Street, Fengtai District, Beijing 100071, China
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48
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Abstract
Staphylococcal enterotoxins SEB and SEC3 and toxic shock syndrome toxin TSST-1 act as superantigens by overstimulating the human immune system and thereby compromise host defense. The mechanism of pathogenesis is explained on the basis of superantigen binding to the MHC class II receptor on the antigen presenting cell and to the T cell receptor (TcR) on the T cell. SEB, SEC3 and TSST-1 bind as intact proteins and make contacts with the alpha1 subdomain (DRalpha) of MHC class II and Vbeta subdomain of TcR. SEB, SEC3 and TSST-1 show specificities for different TcRVbeta isoforms. We have designed three different chimeras linking the same DRalpha with different TcRVbeta isoforms to specifically target SEB, SEC3 and TSST-1 and inhibit their pathogenesis. Here, we show by molecular modeling that the DRalpha, TcRVbeta and linker of a given chimera interact with the target superantigen in a type-specific manner. An initial model of the complex is constructed on the basis of observed inter-molecular contacts between DRalpha/TcRVbeta and the superantigens. A constant temperature (300 K) 200 ps molecular dynamics is performed to sample different conformations of a chimera-superantigen complex by utilizing the flexibility of the (GSTAPPA)(2) linker while maintaining the native folds of superantigen, DRalpha and TcRVbeta and the observed intermolecular contacts. After equilibration, 100 molecular dynamic snapshots are minimized and analyzed. This provides descriptions of various pairwise interactions at the contact interface in the complex and important clues on single site mutations on the chimera that may enhance the stability of a given superantigen-chimera complex.
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Affiliation(s)
- Margit Möllhoff
- Biosciences Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
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49
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Enever C, Tomlinson IM, Lund J, Levens M, Holliger P. Engineering High Affinity Superantigens by Phage Display. J Mol Biol 2005; 347:107-20. [PMID: 15733921 DOI: 10.1016/j.jmb.2005.01.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2004] [Revised: 12/10/2004] [Accepted: 01/05/2005] [Indexed: 11/22/2022]
Abstract
Protein L (PpL) is a B-cell superantigen from Peptostreptococcus magnus known to bind to mammalian Vkappa light chains. PpL from P.magnus strain 312 comprises five homologous immunoglobulin (Ig) binding domains. We first analysed the binding of the individual domains (B1-B5) of PpL(312) to human Vkappa light chains (huVkappa) subtypes 1 (huVkappaI) and 3 (huVkappaIII). Using a combination of rational design and phage selection we isolated mutants of the N-terminal B1 domain with a 14-fold increased affinity for huVkappa1 (B1kappa1) and >tenfold increased affinity for huVkappaIII (B1kappa3). We investigated the potential of the selected domains, in particular the B1kappa1 domain, as reagents in immunochemistry and immunotherapy. B1kappa1 proved a superior reagent than the wild-type domain, allowing up to tenfold more sensitive detection of human Vkappa antibody fragments in ELISA. A fusion protein of B1kappa1 with a human Vlambda antibody scFv fragment promoted the efficient recruitment of antibody encoded effector functions including complement, mononuclear phagocyte respiratory burst and phagocytosis through retargeting of IgGkappa and IgMkappa. Our results suggest that superantigens with improved affinity and/or specificity are easily accessible through protein engineering. Such engineered superantigens should prove useful as reagents in immunochemistry and may have potential as agents in immunotherapy.
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Affiliation(s)
- Carolyn Enever
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK
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50
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Li Y, Luo C, Li W, Xu Z, Zeng C, Bi S, Yu J, Wu J, Yang H. Structure-based preliminary analysis of immunity and virulence of SARS coronavirus. Viral Immunol 2005; 17:528-34. [PMID: 15671749 DOI: 10.1089/vim.2004.17.528] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The research on SARS-associated coronavirus (SARS-CoV) has not stopped since its discovery, but the pathogenesis of SARS is still unclear. To explore the possible molecular mechanisms of the invasion and virulence of SARS-CoV, we investigated the structural basis of the viral proteins using computational biology. Forty-five motifs relating to superantigens, toxins and other bioactive molecules were detected in the proteins of SARS-CoV. The results showed that the distribution of the motifs varied in different proteins. Enzyme-like motifs were located in the R protein, while ICAM- 1-like and toxin-like molecules were located in the spike, envelop, nucleocapsid, PUP1, PUP 2 and PUP 4 proteins. Comparison of SARS-CoV with other viruses (OC43, PEDV, HRSV, HHerpV and HAdenoV) showed that each group of motifs was different for each type of virus. Data suggest that the proteins of SARS-CoV with toxic motifs might play crucial roles in targeting host cells and interfering with the immune system. This study provides new information for drug and vaccine design, as well as therapeutic strategies against SARS.
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Affiliation(s)
- Yan Li
- Beijing Genomics Institute (BGI), Chinese Academy of Sciences (CAS), Beijing, China
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