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Prygiel M, Mosiej E, Polak M, Krysztopa-Grzybowska K, Wdowiak K, Formińska K, Zasada AA. Challenges of Diphtheria Toxin Detection. Toxins (Basel) 2024; 16:245. [PMID: 38922140 PMCID: PMC11209151 DOI: 10.3390/toxins16060245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2024] [Revised: 05/22/2024] [Accepted: 05/24/2024] [Indexed: 06/27/2024] Open
Abstract
Diphtheria toxin (DT) is the main virulence factor of Corynebacterium diphtheriae, C. ulcerans and C. pseudotuberculosis. Moreover, new Corynebacterium species with the potential to produce diphtheria toxin have also been described. Therefore, the detection of the toxin is the most important test in the microbiological diagnosis of diphtheria and other corynebacteria infections. Since the first demonstration in 1888 that DT is a major virulence factor of C. diphtheriae, responsible for the systemic manifestation of the disease, various methods for DT detection have been developed, but the diagnostic usefulness of most of them has not been confirmed on a sufficiently large group of samples. Despite substantial progress in the science and diagnostics of infectious diseases, the Elek test is still the basic recommended diagnostic test for DT detection. The challenge here is the poor availability of an antitoxin and declining experience even in reference laboratories due to the low prevalence of diphtheria in developed countries. However, recent and very promising assays have been developed with the potential for use as rapid point-of-care testing (POCT), such as ICS and LFIA for toxin detection, LAMP for tox gene detection, and biosensors for both.
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Affiliation(s)
| | | | | | | | | | | | - Aleksandra A. Zasada
- Department of Sera and Vaccines Evaluation, National Institute of Public Health NIH—National Research Institute, Chocimska 24, 00-791 Warsaw, Poland; (M.P.); (E.M.); (M.P.); (K.K.-G.); (K.W.); (K.F.)
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2
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Nazari M, Emamzadeh R, Jahanpanah M, Yazdani E, Radmanesh R. A recombinant affitoxin derived from a HER3 affibody and diphteria-toxin has potent and selective antitumor activity. Int J Biol Macromol 2022; 219:1122-1134. [PMID: 36041577 DOI: 10.1016/j.ijbiomac.2022.08.150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 08/08/2022] [Accepted: 08/22/2022] [Indexed: 11/25/2022]
Abstract
High expression of receptor tyrosine-protein kinase erbB-3 (HER3) has been found in several malignancies such as breast cancer. In this study, we designed, produced and evaluated a new affitoxin consisting of a truncated form of diphtheria toxin and a HER3-binding affibody domains. The new affitoxin was expressed in Escherichia coli and purified by affinity chromatography. We evaluated the suitability of affitoxin to kill HER3 positive breast cancer cells with MTT and apoptosis assays. The protein synthesis inhibition was also evaluated. The IC50 value in HER3 negative cells is about 10 times more than HER3 positive cells in new design of affitoxin. The specificity of affitoxin for binding to HER3 positive cells was also investigated with binding assay with flow cytometry. The results show that, the new affitoxin is an anti-cancer molecule with specific binding to HER3 positive cells and may open a new window for the treatment of HER3-positive cancers.
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Affiliation(s)
- Mahboobeh Nazari
- Nanobiotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran; Endocrine Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences, Tehran, Iran.
| | - Rahman Emamzadeh
- Department of Cell and Molecular Biology and Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Iran
| | - Maryam Jahanpanah
- Nanobiotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | - Elnaz Yazdani
- Nanobiotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | - Ramin Radmanesh
- Department of Pharmacoeconomics and Pharmaceutical Management, Faculty of Pharmacy, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
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3
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Cross reacting material (CRM197) as a carrier protein for carbohydrate conjugate vaccines targeted at bacterial and fungal pathogens. Int J Biol Macromol 2022; 218:775-798. [PMID: 35872318 DOI: 10.1016/j.ijbiomac.2022.07.137] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 07/14/2022] [Accepted: 07/18/2022] [Indexed: 11/22/2022]
Abstract
This paper gives an overview of conjugate glycovaccines which contain recombinant diphtheria toxoid CRM197 as a carrier protein. A special focus is given to synthetic methods used for preparation of neoglycoconjugates of CRM197 with oligosaccharide epitopes of cell surface carbohydrates of pathogenic bacteria and fungi. Syntheses of commercial vaccines and laboratory specimen on the basis of CRM197 are outlined briefly.
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4
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Molecular diagnostic of toxigenic Corynebacterium diphtheriae strain by DNA sensor potentially suitable for electrochemical point-of-care diagnostic. Talanta 2021; 227:122161. [PMID: 33714465 DOI: 10.1016/j.talanta.2021.122161] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 01/21/2021] [Accepted: 01/26/2021] [Indexed: 12/12/2022]
Abstract
The presented study is focused on the development of electrochemical genosensor for detection of tox gene fragment of toxigenic Corynebacterium diphtheriae strain. Together with our previous studies it fulfils the whole procedure for fast and accurate diagnostic of diphtheria at its early stage of infection with the use of electrochemical methods. The developed DNA sensor potentially can be used in more sophisticated portable device. After the electrochemical stem-loop probe structure optimization the conditions for real asymmetric PCR (aPCR) product detection were selected. As was shown it was crucial to optimize the magnesium and organic solvent concentrations in detection buffer. Under optimal conditions it was possible to selectively detect as low as 20.8 nM of complementary stand in 5 min or 0.5 nM in 30 min with sensitivity of 12.81 and 0.24 1⋅μM-1 respectively. The unspecific biosensor response was elucidated with the use of new electrode blocking agent, diethyldithiocarbamate. Its application in electrochemical genosensors lead to significant higher current values and the biosensor response even in conditions with magnesium ion depletion. The developed biosensor selectivity was examined using samples containing genetic material originated from a number of non-target bacterial species which potentially can be present in the human upper respiratory tract.
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5
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Reduced nonspecific protein adsorption by application of diethyldithiocarbamate in receptor layer of diphtheria toxoid electrochemical immunosensor. Bioelectrochemistry 2020; 132:107415. [DOI: 10.1016/j.bioelechem.2019.107415] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Revised: 11/12/2019] [Accepted: 11/12/2019] [Indexed: 11/18/2022]
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6
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Zhu S, Liuni P, Ettorre L, Chen T, Szeto J, Carpick B, James DA, Wilson DJ. Hydrogen-Deuterium Exchange Epitope Mapping Reveals Distinct Neutralizing Mechanisms for Two Monoclonal Antibodies against Diphtheria Toxin. Biochemistry 2019; 58:646-656. [PMID: 30560647 DOI: 10.1021/acs.biochem.8b01123] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The diphtheria toxoid (DT) antigen is one of the major components in pediatric and booster combination vaccines and is known to raise a protective humoral immune response upon vaccination. However, a structurally resolved analysis of diphtheria toxin (DTx) epitopes with underlying molecular mechanisms of antibody neutralization has not yet been reported. Using hydrogen-deuterium exchange mass spectrometry (HDX-MS) and Biolayer Interferometry (BLI) assays, we have characterized two neutralizing anti-DTx monoclonal antibodies (mAbs), 2-25 and 2-18, by identifying the specific epitopes on the diphtheria toxin responsible for antibody binding. Our results show that both epitopes are conformational, and mechanistically distinct. Monoclonal antibody 2-25 binds selectively to the B-subunit (translocation and receptor domain) of DTx, blocking the heparin-binding EGF-like growth factor (HBEGF) binding site. In contrast, mAb 2-18 binds to the A-subunit (catalytic domain), partially covering the catalytic loop region that shuttles NAD during catalysis. The results are discussed in the context of antigen neutralization mechanisms and can ultimately help to reveal the underlying factors that contribute to Diptheria vaccine efficacy.
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Affiliation(s)
- Shaolong Zhu
- Process Support and Process Analytical Technologies, Analytical Sciences , Sanofi Pasteur Ltd. , Toronto , Ontario M2R 3T4 , Canada.,Chemistry Department , York University , Toronto , Ontario M3J 1P3 , Canada.,Center for Research in Mass Spectrometry, Department of Chemistry , York University , Toronto , Ontario M3J 1P3 , Canada
| | - Peter Liuni
- Process Support and Process Analytical Technologies, Analytical Sciences , Sanofi Pasteur Ltd. , Toronto , Ontario M2R 3T4 , Canada.,Chemistry Department , York University , Toronto , Ontario M3J 1P3 , Canada.,Center for Research in Mass Spectrometry, Department of Chemistry , York University , Toronto , Ontario M3J 1P3 , Canada
| | - Luciano Ettorre
- Immunology Platform, Analytical Sciences , Sanofi Pasteur Ltd. , Toronto , Ontario M2R 3T4 , Canada
| | - Tricia Chen
- Immunology Platform, Analytical Sciences , Sanofi Pasteur Ltd. , Toronto , Ontario M2R 3T4 , Canada
| | - Jason Szeto
- Immunology Platform, Analytical Sciences , Sanofi Pasteur Ltd. , Toronto , Ontario M2R 3T4 , Canada
| | - Bruce Carpick
- Process Support and Process Analytical Technologies, Analytical Sciences , Sanofi Pasteur Ltd. , Toronto , Ontario M2R 3T4 , Canada
| | - D Andrew James
- Process Support and Process Analytical Technologies, Analytical Sciences , Sanofi Pasteur Ltd. , Toronto , Ontario M2R 3T4 , Canada.,Chemistry Department , York University , Toronto , Ontario M3J 1P3 , Canada
| | - Derek J Wilson
- Chemistry Department , York University , Toronto , Ontario M3J 1P3 , Canada.,Center for Research in Mass Spectrometry, Department of Chemistry , York University , Toronto , Ontario M3J 1P3 , Canada
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7
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Doyle CJ, Mazins A, Graham RMA, Fang NX, Smith HV, Jennison AV. Sequence Analysis of Toxin Gene-Bearing Corynebacterium diphtheriae Strains, Australia. Emerg Infect Dis 2018; 23:105-107. [PMID: 27983494 PMCID: PMC5176206 DOI: 10.3201/eid2301.160584] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
By conducting a molecular characterization of Corynebacterium diphtheriae strains in Australia, we identified novel sequences, nonfunctional toxin genes, and 5 recent cases of toxigenic cutaneous diphtheria. These findings highlight the importance of extrapharyngeal infections for toxin gene-bearing (functional or not) and non-toxin gene-bearing C. diphtheriae strains. Continued surveillance is recommended.
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8
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Membrane-Active Properties of an Amphitropic Peptide from the CyaA Toxin Translocation Region. Toxins (Basel) 2017; 9:toxins9110369. [PMID: 29135925 PMCID: PMC5705984 DOI: 10.3390/toxins9110369] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 11/09/2017] [Accepted: 11/10/2017] [Indexed: 12/28/2022] Open
Abstract
The adenylate cyclase toxin CyaA is involved in the early stages of infection by Bordetella pertussis, the causative agent of whooping cough. CyaA intoxicates target cells by a direct translocation of its catalytic domain (AC) across the plasma membrane and produces supraphysiological levels of cAMP, leading to cell death. The molecular process of AC translocation remains largely unknown, however. We have previously shown that deletion of residues 375–485 of CyaA selectively abrogates AC translocation into eukaryotic cells. We further identified within this “translocation region” (TR), P454 (residues 454–484), a peptide that exhibits membrane-active properties, i.e., is able to bind and permeabilize lipid vesicles. Here, we analyze various sequences from CyaA predicted to be amphipatic and show that although several of these peptides can bind membranes and adopt a helical conformation, only the P454 peptide is able to permeabilize membranes. We further characterize the contributions of the two arginine residues of P454 to membrane partitioning and permeabilization by analyzing the peptide variants in which these residues are substituted by different amino acids (e.g., A, K, Q, and E). Our data shows that both arginine residues significantly contribute, although diversely, to the membrane-active properties of P454, i.e., interactions with both neutral and anionic lipids, helix formation in membranes, and disruption of lipid bilayer integrity. These results are discussed in the context of the translocation process of the full-length CyaA toxin.
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9
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Subrini O, Sotomayor-Pérez AC, Hessel A, Spiaczka-Karst J, Selwa E, Sapay N, Veneziano R, Pansieri J, Chopineau J, Ladant D, Chenal A. Characterization of a membrane-active peptide from the Bordetella pertussis CyaA toxin. J Biol Chem 2013; 288:32585-32598. [PMID: 24064217 PMCID: PMC3820891 DOI: 10.1074/jbc.m113.508838] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 09/09/2013] [Indexed: 12/27/2022] Open
Abstract
Bordetella pertussis, the pathogenic bacteria responsible for whooping cough, secretes several virulence factors, among which is the adenylate cyclase toxin (CyaA) that plays a crucial role in the early stages of human respiratory tract colonization. CyaA invades target cells by translocating its catalytic domain directly across the plasma membrane and overproduces cAMP, leading to cell death. The molecular process leading to the translocation of the catalytic domain remains largely unknown. We have previously shown that the catalytic domain per se, AC384, encompassing residues 1-384 of CyaA, did not interact with lipid bilayer, whereas a longer polypeptide, AC489, spanning residues 1-489, binds to membranes and permeabilizes vesicles. Moreover, deletion of residues 375-485 within CyaA abrogated the translocation of the catalytic domain into target cells. Here, we further identified within this region a peptidic segment that exhibits membrane interaction properties. A synthetic peptide, P454, corresponding to this sequence (residues 454-485 of CyaA) was characterized by various biophysical approaches. We found that P454 (i) binds to membranes containing anionic lipids, (ii) adopts an α-helical structure oriented in plane with respect to the lipid bilayer, and (iii) permeabilizes vesicles. We propose that the region encompassing the helix 454-485 of CyaA may insert into target cell membrane and induce a local destabilization of the lipid bilayer, thus favoring the translocation of the catalytic domain across the plasma membrane.
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Affiliation(s)
- Orso Subrini
- From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France
| | - Ana-Cristina Sotomayor-Pérez
- From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France
| | - Audrey Hessel
- From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France
| | - Johanna Spiaczka-Karst
- From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France
| | - Edithe Selwa
- the Institut Pasteur, CNRS UMR 3528, Unité de Bio-Informatique Structurale, Département de Biologie Structurale et Chimie, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France
| | - Nicolas Sapay
- the Commissariat à l'Energie Atomique, Direction des Sciences de la Vie, Institut de Recherches en Technologies et Sciences pour le Vivant, Laboratoire de Chimie et Biologie des Métaux, CEA Grenoble, 17 Rue des Martyrs, 38054 Grenoble, France
| | - Rémi Veneziano
- the Institut Charles Gerhardt, UMR 5253 CNRS/ENSCM/UM2/UM1, Equipe "Matériaux Avancés pour la Catalyse et la Santé", UFR des Sciences Pharmaceutiques et Biologiques, 15 Avenue Charles Flahault-BP 14 491, 34093 Montpellier Cedex 05, France
| | - Jonathan Pansieri
- the Institut Charles Gerhardt, UMR 5253 CNRS/ENSCM/UM2/UM1, Equipe "Matériaux Avancés pour la Catalyse et la Santé", UFR des Sciences Pharmaceutiques et Biologiques, 15 Avenue Charles Flahault-BP 14 491, 34093 Montpellier Cedex 05, France
| | - Joel Chopineau
- the Institut Charles Gerhardt, UMR 5253 CNRS/ENSCM/UM2/UM1, Equipe "Matériaux Avancés pour la Catalyse et la Santé", UFR des Sciences Pharmaceutiques et Biologiques, 15 Avenue Charles Flahault-BP 14 491, 34093 Montpellier Cedex 05, France; the Université de Nîmes, Rue Docteur Georges Salan, 30021 Nîmes, France
| | - Daniel Ladant
- From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France,.
| | - Alexandre Chenal
- From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France,.
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10
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Karst JC, Barker R, Devi U, Swann MJ, Davi M, Roser SJ, Ladant D, Chenal A. Identification of a region that assists membrane insertion and translocation of the catalytic domain of Bordetella pertussis CyaA toxin. J Biol Chem 2012; 287:9200-12. [PMID: 22241477 DOI: 10.1074/jbc.m111.316166] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The adenylate cyclase (CyaA) toxin, one of the virulence factors secreted by Bordetella pertussis, the pathogenic bacteria responsible for whooping cough, plays a critical role in the early stages of respiratory tract colonization by this bacterium. The CyaA toxin is able to invade eukaryotic cells by translocating its N-terminal catalytic domain directly across the plasma membrane of the target cells, where, activated by endogenous calmodulin, it produces supraphysiological levels of cAMP. How the catalytic domain is transferred from the hydrophilic extracellular medium into the hydrophobic environment of the membrane and then to the cell cytoplasm remains an unsolved question. In this report, we have characterized the membrane-interacting properties of the CyaA catalytic domain. We showed that a protein covering the catalytic domain (AC384, encompassing residues 1-384 of CyaA) displayed no membrane association propensity. However, a longer polypeptide (AC489), encompassing residues 1-489 of CyaA, exhibited the intrinsic property to bind to membranes and to induce lipid bilayer destabilization. We further showed that deletion of residues 375-485 within CyaA totally abrogated the toxin's ability to increase intracellular cAMP in target cells. These results indicate that, whereas the calmodulin dependent enzymatic domain is restricted to the amino-terminal residues 1-384 of CyaA, the membrane-interacting, translocation-competent domain extends up to residue 489. This thus suggests an important role of the region adjacent to the catalytic domain of CyaA in promoting its interaction with and its translocation across the plasma membrane of target cells.
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Affiliation(s)
- Johanna C Karst
- Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Paris, France
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11
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Man P, Montagner C, Vitrac H, Kavan D, Pichard S, Gillet D, Forest E, Forge V. Accessibility Changes within Diphtheria Toxin T Domain upon Membrane Penetration Probed by Hydrogen Exchange and Mass Spectrometry. J Mol Biol 2011; 414:123-34. [DOI: 10.1016/j.jmb.2011.09.042] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Accepted: 09/26/2011] [Indexed: 01/25/2023]
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12
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Xu CH, Sui MH, Tang JB, Shen YQ. What can we learn from virus in designing nonviral gene vectors. CHINESE JOURNAL OF POLYMER SCIENCE 2011. [DOI: 10.1007/s10118-011-1047-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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13
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Chassaing A, Pichard S, Araye-Guet A, Barbier J, Forge V, Gillet D. Solution and membrane-bound chaperone activity of the diphtheria toxin translocation domain towards the catalytic domain. FEBS J 2011; 278:4516-25. [PMID: 21332941 DOI: 10.1111/j.1742-4658.2011.08053.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
During cell intoxication by diphtheria toxin, endosome acidification triggers the translocation of the catalytic (C) domain into the cytoplasm. This event is mediated by the translocation (T) domain of the toxin. Previous work suggested that the T domain acts as a chaperone for the C domain during membrane penetration of the toxin. Using partitioning experiments with lipid vesicles, fluorescence spectroscopy, and a lipid vesicle leakage assay, we characterized the dominant behavior of the T domain over the C domain during the successive steps by which these domains interact with a membrane upon acidification: partial unfolding in solution and during membrane binding, and then structural rearrangement during penetration into the membrane. To this end, we compared, for each domain, isolated or linked together in a CT protein (the toxin lacking the receptor-binding domain), each of these steps. The behavior of the T domain is marginally modified by the presence or absence of the C domain, whereas that of the C domain is greatly affected by the presence of the T domain . All of the steps leading to membrane penetration of the C domain are triggered at higher pH by the T domain , by 0.5-1.6 pH units. The T domain stabilizes the partially folded states of the C domain corresponding to each step of the process. The results unambiguously demonstrate that the T domain acts as a specialized pH-dependent chaperone for the C domain. Interestingly, this chaperone activity acts on very different states of the protein: in solution, membrane-bound, and membrane-inserted.
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Affiliation(s)
- Anne Chassaing
- Commissariat à l'Energie Atomique (CEA), Institut de Biologie et Technologies de Saclay (iBiTecS), Service d'Ingénierie Moléculaire des Protéines (SIMOPRO), Gif sur Yvette, France
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14
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Man P, Montagner C, Vitrac H, Kavan D, Pichard S, Gillet D, Forest E, Forge V. Accessibility changes within diphtheria toxin T domain when in the functional molten globule state, as determined using hydrogen/deuterium exchange measurements. FEBS J 2009; 277:653-62. [PMID: 20050921 DOI: 10.1111/j.1742-4658.2009.07511.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The translocation domain (T domain) of diphtheria toxin adopts a partially folded state, the so-called molten globule state, to become functional at acidic pH. We compared, using hydrogen/deuterium exchange experiments associated with MS, the structures of the T domain in its soluble folded state at neutral pH and in its functional molten globule state at acidic pH. In the native state, the alpha-helices TH5 and TH8 are identified as the core of the domain. Based on the high-resolution structure of the T domain, we propose that TH8 is highly protected because it is buried within the native structure. According to the same structure, TH5 is partly accessible at the surface of the T domain. We propose that its high protection is caused by the formation of dimers. Within the molten globule state, high protection is still observed within the helical hairpin TH8-TH9, which is responsible for the insertion of the T domain into the membrane. In the absence of the lipid bilayer, this hydrophobic part of the domain self-assembles, leading to the formation of oligomers. Overall, hydrogen/deuterium-exchange measurements allow the analysis of interaction contacts within small oligomers made of partially folded proteins. Such information, together with crystal structure data, are particularly valuable for using to analyze the self-assembly of proteins.
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Affiliation(s)
- Petr Man
- Laboratoire de Spectrométrie de Masse des Protéines, Institut de Biologie Structurale (CEA, CNRS, UJF, UMR 5075), Grenoble, France
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15
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Deciphering Membrane Insertion of the Diphtheria Toxin T Domain by Specular Neutron Reflectometry and Solid-State NMR Spectroscopy. J Mol Biol 2009; 391:872-83. [DOI: 10.1016/j.jmb.2009.06.061] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 06/15/2009] [Accepted: 06/24/2009] [Indexed: 11/23/2022]
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16
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Galloux M, Vitrac H, Montagner C, Raffestin S, Popoff MR, Chenal A, Forge V, Gillet D. Membrane Interaction of botulinum neurotoxin A translocation (T) domain. The belt region is a regulatory loop for membrane interaction. J Biol Chem 2008; 283:27668-27676. [PMID: 18693250 DOI: 10.1074/jbc.m802557200] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The translocation of the catalytic domain through the membrane of the endosome to the cell cytoplasm is a key step of intoxication by botulinum neurotoxin (BoNT). This step is mediated by the translocation (T) domain upon endosome acidification, although the mechanism of interaction of the T domain with the membrane is still poorly understood. Using physicochemical approaches and spectroscopic methods, we studied the interaction of the BoNT/A T domain with the membrane as a function of pH. We found that the interaction with membranes does not involve major secondary or tertiary structural changes, as reported for other toxins like diphtheria toxin. The T domain becomes insoluble around its pI value and then penetrates into the membrane. At that stage, the T domain becomes able to permeabilize lipid vesicles. This occurs for pH values lower than 5.5, in agreement with the pH encountered by the toxin within endosomes. Electrostatic interactions are also important for the process. The role of the so-called belt region was investigated with four variant proteins presenting different lengths of the N-extremity of the T domain. We observed that this part of the T domain, which contains numerous negatively charged residues, limits the protein-membrane interaction. Indeed, interaction with the membrane of the protein deleted of this extremity takes place for higher pH values than for the entire T domain. Overall, the data suggest that acidification eliminates repulsive electrostatic interactions between the T domain and the membrane, allowing its penetration into the membrane without triggering detectable structural changes.
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Affiliation(s)
- Marie Galloux
- Commissariat à l'Energie Atomique (CEA), Institut de Biologie et Technologies de Saclay (iBiTecS), Service d'Ingénierie Moléculaire des Protéines (SIMOPRO), F-91191 Gif sur Yvette, France
| | - Heidi Vitrac
- Institut de Recherche en Technologies et Sciences pour le Vivant (IRTSV), Laboratoire de Chimie Biologie des Métaux (LCBM), UMR CEA-CNRS-UJF 5249, F-38054 Grenoble, France
| | - Caroline Montagner
- Institut de Recherche en Technologies et Sciences pour le Vivant (IRTSV), Laboratoire de Chimie Biologie des Métaux (LCBM), UMR CEA-CNRS-UJF 5249, F-38054 Grenoble, France
| | - Stéphanie Raffestin
- Commissariat à l'Energie Atomique (CEA), Institut de Biologie et Technologies de Saclay (iBiTecS), Service d'Ingénierie Moléculaire des Protéines (SIMOPRO), F-91191 Gif sur Yvette, France
| | - Michel R Popoff
- Institut Pasteur, Unité des Bactéries Anaérobies et Toxines, 75724 Paris cedex 15, France
| | - Alexandre Chenal
- Unité de Biochimie des Interactions Moléculaires, URA CNRS 2185, Département de Biologie Structurale et Chimie, 25-28 rue du Dr Roux, 75724 Paris cedex 15, France
| | - Vincent Forge
- Institut de Recherche en Technologies et Sciences pour le Vivant (IRTSV), Laboratoire de Chimie Biologie des Métaux (LCBM), UMR CEA-CNRS-UJF 5249, F-38054 Grenoble, France.
| | - Daniel Gillet
- Commissariat à l'Energie Atomique (CEA), Institut de Biologie et Technologies de Saclay (iBiTecS), Service d'Ingénierie Moléculaire des Protéines (SIMOPRO), F-91191 Gif sur Yvette, France.
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Oligomerization of membrane-bound diphtheria toxin (CRM197) facilitates a transition to the open form and deep insertion. Biophys J 2007; 94:2115-27. [PMID: 18055530 DOI: 10.1529/biophysj.107.113498] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Diphtheria toxin (DT) contains separate domains for receptor-specific binding, translocation, and enzymatic activity. After binding to cells, DT is taken up into endosome-like acidic compartments where the translocation domain inserts into the endosomal membrane and releases the catalytic domain into the cytosol. The process by which the catalytic domain is translocated across the endosomal membrane is known to involve pH-induced conformational changes; however, the molecular mechanisms are not yet understood, in large part due to the challenge of probing the conformation of the membrane-bound protein. In this work neutron reflection provided detailed conformational information for membrane-bound DT (CRM197) in situ. The data revealed that the bound toxin oligomerizes with increasing DT concentration and that the oligomeric form (and only the oligomeric form) undergoes a large extension into solution with decreasing pH that coincides with deep insertion of residues into the membrane. We interpret the large extension as a transition to the open form. These results thus indicate that as a function of bulk DT concentration, adsorbed DT passes from an inactive state with a monomeric dimension normal to the plane of the membrane to an active state with a dimeric dimension normal to the plane of the membrane.
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18
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Perier A, Chassaing A, Raffestin S, Pichard S, Masella M, Ménez A, Forge V, Chenal A, Gillet D. Concerted Protonation of Key Histidines Triggers Membrane Interaction of the Diphtheria Toxin T Domain. J Biol Chem 2007; 282:24239-45. [PMID: 17584737 DOI: 10.1074/jbc.m703392200] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The translocation domain (T domain) of the diphtheria toxin contributes to the transfer of the catalytic domain from the cell endosome to the cytosol, where it blocks protein synthesis. Translocation is initiated when endosome acidification induces the interaction of the T domain with the membrane of the compartment. We found that the protonation of histidine side chains triggers the conformational changes required for membrane interaction. All histidines are involved in a concerted manner, but none is indispensable. However, the preponderance of each histidine varies according to the transition observed. The pair His(223)-His(257) and His(251) are the most sensitive triggers for the formation of the molten globule state in solution, whereas His(322)-His(323) and His(251) are the most sensitive triggers for membrane binding. Interestingly, the histidines are located at key positions throughout the structure of the protein, in hinges and at the interface between each of the three layers of helices forming the domain. Their protonation induces local destabilizations, disrupting the tertiary structure and favoring membrane interaction. We propose that the selection of histidine residues as triggers of membrane interaction enables the T domain to initiate translocation at the rather mild pH found in the endosome, contributing to toxin efficacy.
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Affiliation(s)
- Aurélie Perier
- Commissariat à l'Energie Atomique, Institut de Biologie et Technologies de Saclay, Service d'Ingénierie Moléculaire des Protéines, Gif-sur-Yvette F-91191, France
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19
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Perez-Campo FM, Spencer HL, Elder RH, Stern PL, Ward CM. Novel vectors for homologous recombination strategies in mouse embryonic stem cells: an ES cell line expressing EGFP under control of the 5T4 promoter. Exp Cell Res 2007; 313:3604-15. [PMID: 17765223 DOI: 10.1016/j.yexcr.2007.07.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2007] [Revised: 07/12/2007] [Accepted: 07/13/2007] [Indexed: 01/28/2023]
Abstract
The use of gene mutation/knock-out strategies in mouse embryonic stem (ES) cells has revolutionized the study of gene function in ES cells and embryonic development. However, the construction of vectors for homologous recombination strategies requires considerable expertise and time. We describe two novel vectors that can generate site specific knock-out or EGFP knock-in ES cells within 6 weeks from construct design to identification of positive ES cell clones. As proof-of-principle, we have utilized the knock-out targeting vector to modify the NEIL2 locus in ES cells. In addition, using the knock-in vector, we have inserted EGFP downstream of the 5T4 oncofetal antigen promoter in ES cells (5T4-GFP ES cells). Undifferentiated 5T4-GFP ES cells lack EGFP and maintain expression of the pluripotent markers OCT-4 and NANOG. Upon differentiation, EGFP expression is increased in 5T4-GFP ES cells and this correlates with 5T4 transcript expression of the unmodified allele, loss of Nanog and Oct-4 transcripts and upregulation of differentiation-associated transcripts. Furthermore, we demonstrate that fluorescent activated cell sorting of 5T4-GFP ES cells allows isolation of pluripotent or differentiated cells from a heterogeneous population. These vectors provide researchers with a rapid method of modifying specific ES cell genes to study cellular differentiation and embryonic development.
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Affiliation(s)
- Flor M Perez-Campo
- Stem Cell Biology Group, Paterson Institute for Cancer Research, Christie Hospital NHS Trust, Wilmslow Road, Manchester, UK
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20
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Chenal A, Savarin P, Nizard P, Guillain F, Gillet D, Forge V. Membrane protein insertion regulated by bringing electrostatic and hydrophobic interactions into play. A case study with the translocation domain of diphtheria toxin. J Biol Chem 2002; 277:43425-32. [PMID: 12193591 DOI: 10.1074/jbc.m204148200] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The study of the membrane insertion of the translocation domain of diphtheria toxin deepens our insight into the interactions between proteins and membranes. During cell intoxication, this domain undergoes a change from a soluble and folded state at alkaline pH to a functional membrane-inserted state at acid pH. We found that hydrophobic and electrostatic interactions occur in a sequential manner between the domain and the membrane during the insertion. The first step involves hydrophobic interactions by the C-terminal region. This is because of the pH-induced formation of a molten globule specialized for binding to the membrane. Accumulation of this molten globule follows a precise molecular mechanism adapted to the toxin function. The second step, as the pH decreases, leads to the functional inserted state. It arises from the changes in the balance of electrostatic attractions and repulsions between the N-terminal part and the membrane. Our study shows how the structural changes and the interaction with membranes of the translocation domain are finely tuned by pH changes to take advantage of the cellular uptake system.
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Affiliation(s)
- Alexandre Chenal
- Département d'Ingénierie et d'Etudes des Protéines, CEA-Saclay, 91191 Gif sur Yvette cedex, France
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