1
|
Schlenker C, Richard K, Skobelkina S, Mathena RP, Perkins DJ. ER-transiting bacterial toxins amplify STING innate immune responses and elicit ER stress. Infect Immun 2024; 92:e0030024. [PMID: 39057915 PMCID: PMC11321001 DOI: 10.1128/iai.00300-24] [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: 07/12/2024] [Accepted: 07/12/2024] [Indexed: 07/28/2024] Open
Abstract
The cGAS/STING sensor system drives innate immune responses to intracellular microbial double-stranded DNA (dsDNA) and bacterial cyclic nucleotide second messengers (e.g., c-di-AMP). STING-dependent cell-intrinsic responses can increase resistance to microbial infection and speed pathogen clearance. Correspondingly, STING activation and signaling are known to be targeted for suppression by effectors from several bacterial pathogens. Whether STING responses are also positively regulated through sensing of specific bacterial effectors is less clear. We find that STING activation through dsDNA, by its canonical ligand 2'-3' cGAMP, or the small molecule DMXAA is potentiated following intracellular delivery of the AB5 toxin family member pertussis toxin from Bordetella pertussis or the B subunit of cholera toxin from Vibrio cholerae. Entry of pertussis toxin or cholera toxin B into mouse macrophages triggers markers of endoplasmic reticulum (ER) stress and enhances ligand-dependent STING responses at the level of STING receptor activation in a manner that is independent of toxin enzymatic activity. Our results provide an example in which STING responses integrate information about the presence of relevant ER-transiting bacterial toxins into the innate inflammatory response and may help to explain the in vivo adjuvant effects of catalytically inactive toxins.
Collapse
Affiliation(s)
- Catherine Schlenker
- Program in Oncology University of Maryland, Baltimore (UMB), School of Medicine, Baltimore, Maryland, USA
| | - Katharina Richard
- Department of Microbiology and Immunology, School of Medicine, Baltimore, Maryland, USA
| | - Sofia Skobelkina
- Program in Oncology University of Maryland, Baltimore (UMB), School of Medicine, Baltimore, Maryland, USA
| | - R. Paige Mathena
- Department of Microbiology and Immunology, School of Medicine, Baltimore, Maryland, USA
| | - Darren J. Perkins
- Program in Oncology University of Maryland, Baltimore (UMB), School of Medicine, Baltimore, Maryland, USA
- Department of Microbiology and Immunology, School of Medicine, Baltimore, Maryland, USA
| |
Collapse
|
2
|
Jia J, Lietz S, Barth H, Ernst K. The antiarrhythmic drugs amiodarone and dronedarone inhibit intoxication of cells with pertussis toxin. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2024:10.1007/s00210-024-03247-9. [PMID: 38958734 DOI: 10.1007/s00210-024-03247-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2024] [Accepted: 06/17/2024] [Indexed: 07/04/2024]
Abstract
Pertussis toxin (PT) is a virulent factor produced by Bordetella pertussis, the causative agent of whooping cough. PT exerts its pathogenic effects by ADP-ribosylating heterotrimeric G proteins, disrupting cellular signaling pathways. Here, we investigate the potential of two antiarrhythmic drugs, amiodarone and dronedarone, in mitigating PT-induced cellular intoxication. After binding to cells, PT is endocytosed, transported from the Golgi to the endoplasmic reticulum where the enzyme subunit PTS1 is released from the transport subunit of PT. PTS1 is translocated into the cytosol where it ADP-ribosylates inhibitory α-subunit of G-protein coupled receptors (Gαi). We showed that amiodarone and dronedarone protected CHO cells and human A549 cells from PT-intoxication by analyzing the ADP-ribosylation status of Gαi. Amiodarone had no effect on PT binding to cells or in vitro enzyme activity of PTS1 but reduced the signal of PTS1 in the cell suggesting that amiodarone interferes with intracellular transport of PTS1. Moreover, dronedarone mitigated the PT-mediated effect on cAMP signaling in a cell-based bioassay. Taken together, our findings underscore the inhibitory effects of amiodarone and dronedarone on PT-induced cellular intoxication, providing valuable insights into drug repurposing for infectious disease management.
Collapse
Affiliation(s)
- Jinfang Jia
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, Ulm, Germany
- Department of Respiratory Medicine, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 600 Yishan Road, Shanghai, 200233, China
| | - Stefanie Lietz
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, Ulm, Germany
| | - Holger Barth
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, Ulm, Germany.
| | - Katharina Ernst
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, Ulm, Germany.
| |
Collapse
|
3
|
Jia J, Zoeschg M, Barth H, Pulliainen AT, Ernst K. The Chaperonin TRiC/CCT Inhibitor HSF1A Protects Cells from Intoxication with Pertussis Toxin. Toxins (Basel) 2024; 16:36. [PMID: 38251252 PMCID: PMC10819386 DOI: 10.3390/toxins16010036] [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: 11/02/2023] [Revised: 01/03/2024] [Accepted: 01/07/2024] [Indexed: 01/23/2024] Open
Abstract
Pertussis toxin (PT) is a bacterial AB5-toxin produced by Bordetella pertussis and a major molecular determinant of pertussis, also known as whooping cough, a highly contagious respiratory disease. In this study, we investigate the protective effects of the chaperonin TRiC/CCT inhibitor, HSF1A, against PT-induced cell intoxication. TRiC/CCT is a chaperonin complex that facilitates the correct folding of proteins, preventing misfolding and aggregation, and maintaining cellular protein homeostasis. Previous research has demonstrated the significance of TRiC/CCT in the functionality of the Clostridioides difficile TcdB AB-toxin. Our findings reveal that HSF1A effectively reduces the levels of ADP-ribosylated Gαi, the specific substrate of PT, in PT-treated cells, without interfering with enzyme activity in vitro or the cellular binding of PT. Additionally, our study uncovers a novel interaction between PTS1 and the chaperonin complex subunit CCT5, which correlates with reduced PTS1 signaling in cells upon HSF1A treatment. Importantly, HSF1A mitigates the adverse effects of PT on cAMP signaling in cellular systems. These results provide valuable insights into the mechanisms of PT uptake and suggest a promising starting point for the development of innovative therapeutic strategies to counteract pertussis toxin-mediated pathogenicity.
Collapse
Affiliation(s)
- Jinfang Jia
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, 89081 Ulm, Germany
| | - Manuel Zoeschg
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, 89081 Ulm, Germany
| | - Holger Barth
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, 89081 Ulm, Germany
| | | | - Katharina Ernst
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, 89081 Ulm, Germany
| |
Collapse
|
4
|
Guyette JL, Serrano A, Huhn III GR, Taylor M, Malkòm P, Curtis D, Teter K. Reduction is sufficient for the disassembly of ricin and Shiga toxin 1 but not Escherichia coli heat-labile enterotoxin. Infect Immun 2023; 91:e0033223. [PMID: 37877711 PMCID: PMC10652930 DOI: 10.1128/iai.00332-23] [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: 08/21/2023] [Accepted: 09/21/2023] [Indexed: 10/26/2023] Open
Abstract
Many AB toxins contain an enzymatic A moiety that is anchored to a cell-binding B moiety by a disulfide bridge. After receptor-mediated endocytosis, some AB toxins undergo retrograde transport to the endoplasmic reticulum (ER) where reduction of the disulfide bond occurs. The reduced A subunit then dissociates from the holotoxin and enters the cytosol to alter its cellular target. Intoxication requires A chain separation from the holotoxin, but, for many toxins, it is unclear if reduction alone is sufficient for toxin disassembly. Here, we examined the link between reduction and disassembly for several ER-translocating toxins. We found disassembly of the reduced Escherichia coli heat-labile enterotoxin (Ltx) required an interaction with one specific ER-localized oxidoreductase: protein disulfide isomerase (PDI). In contrast, the reduction and disassembly of ricin toxin (Rtx) and Shiga toxin 1 (Stx1) were coupled events that did not require PDI and could be triggered by reductant alone. PDI-deficient cells accordingly exhibited high resistance to Ltx with continued sensitivity to Rtx and Stx1. The distinct structural organization of each AB toxin thus appears to determine whether holotoxin disassembly occurs spontaneously upon disulfide reduction or requires the additional input of PDI.
Collapse
Affiliation(s)
- Jessica L. Guyette
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - Albert Serrano
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - G. Robb Huhn III
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - Michael Taylor
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - Pat Malkòm
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - David Curtis
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - Ken Teter
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| |
Collapse
|
5
|
Jia J, Braune-Yan M, Lietz S, Wahba M, Pulliainen AT, Barth H, Ernst K. Domperidone Inhibits Clostridium botulinum C2 Toxin and Bordetella pertussis Toxin. Toxins (Basel) 2023; 15:412. [PMID: 37505681 PMCID: PMC10467066 DOI: 10.3390/toxins15070412] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 06/13/2023] [Accepted: 06/20/2023] [Indexed: 07/29/2023] Open
Abstract
Bordetella pertussis toxin (PT) and Clostridium botulinum C2 toxin are ADP-ribosylating toxins causing severe diseases in humans and animals. They share a common translocation mechanism requiring the cellular chaperones Hsp90 and Hsp70, cyclophilins, and FK506-binding proteins to transport the toxins' enzyme subunits into the cytosol. Inhibitors of chaperone activities have been shown to reduce the amount of transported enzyme subunits into the cytosol of cells, thus protecting cells from intoxication by these toxins. Recently, domperidone, an approved dopamine receptor antagonist drug, was found to inhibit Hsp70 activity. Since Hsp70 is required for cellular toxin uptake, we hypothesized that domperidone also protects cells from intoxication with PT and C2. The inhibition of intoxication by domperidone was demonstrated by analyzing the ADP-ribosylation status of the toxins' specific substrates. Domperidone had no inhibitory effect on the receptor-binding or enzyme activity of the toxins, but it inhibited the pH-driven membrane translocation of the enzyme subunit of the C2 toxin and reduced the amount of PTS1 in cells. Taken together, our results indicate that domperidone is a potent inhibitor of PT and C2 toxins in cells and therefore might have therapeutic potential by repurposing domperidone to treat diseases caused by bacterial toxins that require Hsp70 for their cellular uptake.
Collapse
Affiliation(s)
- Jinfang Jia
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, 89081 Ulm, Germany
| | - Maria Braune-Yan
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, 89081 Ulm, Germany
| | - Stefanie Lietz
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, 89081 Ulm, Germany
| | - Mary Wahba
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, 89081 Ulm, Germany
| | | | - Holger Barth
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, 89081 Ulm, Germany
| | - Katharina Ernst
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, 89081 Ulm, Germany
| |
Collapse
|
6
|
Kling C, Sommer A, Almeida-Hernandez Y, Rodríguez A, Perez-Erviti JA, Bhadane R, Ständker L, Wiese S, Barth H, Pupo-Meriño M, Pulliainen AT, Sánchez-García E, Ernst K. Inhibition of Pertussis Toxin by Human α-Defensins-1 and -5: Differential Mechanisms of Action. Int J Mol Sci 2023; 24:10557. [PMID: 37445740 DOI: 10.3390/ijms241310557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 06/16/2023] [Accepted: 06/16/2023] [Indexed: 07/15/2023] Open
Abstract
Whooping cough is a severe childhood disease, caused by the bacterium Bordetella pertussis, which releases pertussis toxin (PT) as a major virulence factor. Previously, we identified the human antimicrobial peptides α-defensin-1 and -5 as inhibitors of PT and demonstrated their capacity to inhibit the activity of the PT enzyme subunit PTS1. Here, the underlying mechanism of toxin inhibition was investigated in more detail, which is essential for developing the therapeutic potential of these peptides. Flow cytometry and immunocytochemistry revealed that α-defensin-5 strongly reduced PT binding to, and uptake into cells, whereas α-defensin-1 caused only a mild reduction. Conversely, α-defensin-1, but not α-defensin-5 was taken up into different cell lines and interacted with PTS1 inside cells, based on proximity ligation assay. In-silico modeling revealed specific interaction interfaces for α-defensin-1 with PTS1 and vice versa, unlike α-defensin-5. Dot blot experiments showed that α-defensin-1 binds to PTS1 and even stronger to its substrate protein Gαi in vitro. NADase activity of PTS1 in vitro was not inhibited by α-defensin-1 in the absence of Gαi. Taken together, these results suggest that α-defensin-1 inhibits PT mainly by inhibiting enzyme activity of PTS1, whereas α-defensin-5 mainly inhibits cellular uptake of PT. These findings will pave the way for optimization of α-defensins as novel therapeutics against whooping cough.
Collapse
Affiliation(s)
- Carolin Kling
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, 89081 Ulm, Germany
| | - Anja Sommer
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, 89081 Ulm, Germany
| | - Yasser Almeida-Hernandez
- Computational Bioengineering, Fakultät Bio- und Chemieingenieurwesen, Technische Universität Dortmund, 44227 Dortmund, Germany
| | - Armando Rodríguez
- Core Facility Functional Peptidomics, Faculty of Medicine, Ulm University, 89081 Ulm, Germany
- Core Unit Mass Spectrometry and Proteomics, Faculty of Medicine, Ulm University, 89081 Ulm, Germany
| | - Julio A Perez-Erviti
- Computational Bioengineering, Fakultät Bio- und Chemieingenieurwesen, Technische Universität Dortmund, 44227 Dortmund, Germany
| | - Rajendra Bhadane
- Institute of Biomedicine, University of Turku, FI-20520 Turku, Finland
| | - Ludger Ständker
- Core Facility Functional Peptidomics, Faculty of Medicine, Ulm University, 89081 Ulm, Germany
| | - Sebastian Wiese
- Core Unit Mass Spectrometry and Proteomics, Faculty of Medicine, Ulm University, 89081 Ulm, Germany
| | - Holger Barth
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, 89081 Ulm, Germany
| | - Mario Pupo-Meriño
- Departamento de Bioinformática, Centro de Matemática Computacional, Universidad de las Ciencias Informáticas (UCI), Havana 19370, Cuba
| | - Arto T Pulliainen
- Institute of Biomedicine, University of Turku, FI-20520 Turku, Finland
| | - Elsa Sánchez-García
- Computational Bioengineering, Fakultät Bio- und Chemieingenieurwesen, Technische Universität Dortmund, 44227 Dortmund, Germany
| | - Katharina Ernst
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, 89081 Ulm, Germany
| |
Collapse
|
7
|
Sakari M, Tran MT, Rossjohn J, Pulliainen AT, Beddoe T, Littler DR. Crystal structures of pertussis toxin with NAD+ and analogs provide structural insights into the mechanism of its cytosolic ADP-ribosylation activity. J Biol Chem 2022; 298:101892. [PMID: 35378130 PMCID: PMC9079181 DOI: 10.1016/j.jbc.2022.101892] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 03/17/2022] [Accepted: 03/18/2022] [Indexed: 11/19/2022] Open
Abstract
Bordetella pertussis is the causative agent of whooping cough, a highly contagious respiratory disease. Pertussis toxin (PT), a major virulence factor secreted by B. pertussis, is an AB5-type protein complex topologically related to cholera toxin. The PT protein complex is internalized by host cells and follows a retrograde trafficking route to the endoplasmic reticulum, where it subsequently dissociates. The released enzymatic S1 subunit is then translocated from the endoplasmic reticulum into the cytosol and subsequently ADP-ribosylates the inhibitory alpha-subunits (Gαi) of heterotrimeric G proteins, thus promoting dysregulation of G protein–coupled receptor signaling. However, the mechanistic details of the ADP-ribosylation activity of PT are not well understood. Here, we describe crystal structures of the S1 subunit in complex with nicotinamide adenine dinucleotide (NAD+), with NAD+ hydrolysis products ADP-ribose and nicotinamide, with NAD+ analog PJ34, and with a novel NAD+ analog formed upon S1 subunit crystallization with 3-amino benzamide and NAD+, which we name benzamide amino adenine dinucleotide. These crystal structures provide unprecedented insights into pre- and post-NAD+ hydrolysis steps of the ADP-ribosyltransferase activity of PT. We propose that these data may aid in rational drug design approaches and further development of PT-specific small-molecule inhibitors.
Collapse
Affiliation(s)
- Moona Sakari
- Institute of Biomedicine, Research Unit for Infection and Immunity, University of Turku, Turku, Finland
| | - Mai T Tran
- Infection and Immunity Program & Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Jamie Rossjohn
- Infection and Immunity Program & Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia; Institute of Infection and Immunity, School of Medicine, Cardiff University, Heath Park, Cardiff, Wales, United Kingdom
| | - Arto T Pulliainen
- Institute of Biomedicine, Research Unit for Infection and Immunity, University of Turku, Turku, Finland.
| | - Travis Beddoe
- Department of Animal, Plant and Soil Science and Centre for AgriBioscience, La Trobe University, Bundoora, Victoria, Australia.
| | - Dene R Littler
- Infection and Immunity Program & Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia.
| |
Collapse
|
8
|
Novel Strategies to Inhibit Pertussis Toxin. Toxins (Basel) 2022; 14:toxins14030187. [PMID: 35324684 PMCID: PMC8951090 DOI: 10.3390/toxins14030187] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 02/28/2022] [Accepted: 03/01/2022] [Indexed: 11/25/2022] Open
Abstract
Pertussis, also known as whooping cough, is a respiratory disease caused by infection with Bordetella pertussis, which releases several virulence factors, including the AB-type pertussis toxin (PT). The characteristic symptom is severe, long-lasting paroxysmal coughing. Especially in newborns and infants, pertussis symptoms, such as leukocytosis, can become life-threatening. Despite an available vaccination, increasing case numbers have been reported worldwide, including Western countries such as Germany and the USA. Antibiotic treatment is available and important to prevent further transmission. However, antibiotics only reduce symptoms if administered in early stages, which rarely occurs due to a late diagnosis. Thus, no causative treatments against symptoms of whooping cough are currently available. The AB-type protein toxin PT is a main virulence factor and consists of a binding subunit that facilitates transport of an enzyme subunit into the cytosol of target cells. There, the enzyme subunit ADP-ribosylates inhibitory α-subunits of G-protein coupled receptors resulting in disturbed cAMP signaling. As an important virulence factor associated with severe symptoms, such as leukocytosis, and poor outcomes, PT represents an attractive drug target to develop novel therapeutic strategies. In this review, chaperone inhibitors, human peptides, small molecule inhibitors, and humanized antibodies are discussed as novel strategies to inhibit PT.
Collapse
|
9
|
Overgaard E, Morris B, Mohammad Mousa O, Price E, Rodriguez A, Cufurovic L, Beard RS, Tinker JK. Cellular Activity of Salmonella Typhimurium ArtAB Toxin and Its Receptor-Binding Subunit. Toxins (Basel) 2021; 13:toxins13090599. [PMID: 34564603 PMCID: PMC8472264 DOI: 10.3390/toxins13090599] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 08/07/2021] [Accepted: 08/20/2021] [Indexed: 12/22/2022] Open
Abstract
Salmonellosis is among the most reported foodborne illnesses in the United States. The Salmonellaenterica Typhimurium DT104 phage type, which is associated with multidrug-resistant disease in humans and animals, possesses an ADP-ribosylating toxin called ArtAB. Full-length artAB has been found on a number of broad-host-range non-typhoidal Salmonella species and serovars. ArtAB is also homologous to many AB5 toxins from diverse Gram-negative pathogens, including cholera toxin (CT) and pertussis toxin (PT), and may be involved in Salmonella pathogenesis, however, in vitro cellular toxicity of ArtAB has not been characterized. artAB was cloned into E. coli and initially isolated using a histidine tag (ArtABHIS) and nickel chromatography. ArtABHIS was found to bind to African green monkey kidney epithelial (Vero) cells using confocal microscopy and to interact with glycans present on fetuin and monosialotetrahexosylganglioside (GM1) using ELISA. Untagged, or native, holotoxin (ArtAB), and the pentameric receptor-binding subunit (ArtB) were purified from E. coli using fetuin and d-galactose affinity chromatography. ArtAB and ArtB metabolic and cytotoxic activities were determined using Vero and Chinese hamster ovary (CHO) epithelial cells. Vero cells were more sensitive to ArtAB, however, incubation with both cell types revealed only partial cytotoxicity over 72 h, similar to that induced by CT. ArtAB induced a distinctive clustering phenotype on CHO cells over 72 h, similar to PT, and an elongated phenotype on Vero cells, similar to CT. The ArtB binding subunit alone also had a cytotoxic effect on CHO cells and induced morphological rounding. Results indicate that this toxin induces distinctive cellular outcomes. Continued biological characterization of ArtAB will advance efforts to prevent disease caused by non-typhoidal Salmonella.
Collapse
Affiliation(s)
- Elise Overgaard
- Biomolecular Sciences Graduate Program, Boise State University, Boise, ID 83725, USA;
| | - Brad Morris
- Department of Biology, Boise State University, Boise, ID 83725, USA; (B.M.); (O.M.M.); (A.R.); (L.C.)
| | - Omid Mohammad Mousa
- Department of Biology, Boise State University, Boise, ID 83725, USA; (B.M.); (O.M.M.); (A.R.); (L.C.)
| | - Emily Price
- Idaho Veterans Research and Education Foundation, Infectious Diseases Section, Boise, ID 83702, USA;
| | - Adriana Rodriguez
- Department of Biology, Boise State University, Boise, ID 83725, USA; (B.M.); (O.M.M.); (A.R.); (L.C.)
| | - Leyla Cufurovic
- Department of Biology, Boise State University, Boise, ID 83725, USA; (B.M.); (O.M.M.); (A.R.); (L.C.)
| | - Richard S. Beard
- Biomolecular Research Center, Boise State University, Boise, ID 83725, USA;
| | - Juliette K. Tinker
- Biomolecular Sciences Graduate Program, Boise State University, Boise, ID 83725, USA;
- Department of Biology, Boise State University, Boise, ID 83725, USA; (B.M.); (O.M.M.); (A.R.); (L.C.)
- Correspondence: ; Tel.: +1-208-426-5472
| |
Collapse
|
10
|
Kling C, Pulliainen AT, Barth H, Ernst K. Human Peptides α-Defensin-1 and -5 Inhibit Pertussis Toxin. Toxins (Basel) 2021; 13:toxins13070480. [PMID: 34357952 PMCID: PMC8310310 DOI: 10.3390/toxins13070480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/01/2021] [Accepted: 07/09/2021] [Indexed: 01/13/2023] Open
Abstract
Bordetella pertussis causes the severe childhood disease whooping cough, by releasing several toxins, including pertussis toxin (PT) as a major virulence factor. PT is an AB5-type toxin, and consists of the enzymatic A-subunit PTS1 and five B-subunits, which facilitate binding to cells and transport of PTS1 into the cytosol. PTS1 ADP-ribosylates α-subunits of inhibitory G-proteins (Gαi) in the cytosol, which leads to disturbed cAMP signaling. Since PT is crucial for causing severe courses of disease, our aim is to identify new inhibitors against PT, to provide starting points for novel therapeutic approaches. Here, we investigated the effect of human antimicrobial peptides of the defensin family on PT. We demonstrated that PTS1 enzyme activity in vitro was inhibited by α-defensin-1 and -5, but not β-defensin-1. The amount of ADP-ribosylated Gαi was significantly reduced in PT-treated cells, in the presence of α-defensin-1 and -5. Moreover, both α-defensins decreased PT-mediated effects on cAMP signaling in the living cell-based interference in the Gαi-mediated signal transduction (iGIST) assay. Taken together, we identified the human peptides α-defensin-1 and -5 as inhibitors of PT activity, suggesting that these human peptides bear potential for developing novel therapeutic strategies against whooping cough.
Collapse
Affiliation(s)
- Carolin Kling
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, 89081 Ulm, Germany; (C.K.); (H.B.)
| | - Arto T. Pulliainen
- Institute of Biomedicine, Research Unit for Infection and Immunity, University of Turku, FI-20520 Turku, Finland;
| | - Holger Barth
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, 89081 Ulm, Germany; (C.K.); (H.B.)
| | - Katharina Ernst
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, 89081 Ulm, Germany; (C.K.); (H.B.)
- Correspondence:
| |
Collapse
|
11
|
Ernst K, Mittler AK, Winkelmann V, Kling C, Eberhardt N, Anastasia A, Sonnabend M, Lochbaum R, Wirsching J, Sakari M, Pulliainen AT, Skerry C, Carbonetti NH, Frick M, Barth H. Pharmacological targeting of host chaperones protects from pertussis toxin in vitro and in vivo. Sci Rep 2021; 11:5429. [PMID: 33686161 PMCID: PMC7940712 DOI: 10.1038/s41598-021-84817-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 02/16/2021] [Indexed: 01/05/2023] Open
Abstract
Whooping cough is caused by Bordetella pertussis that releases pertussis toxin (PT) which comprises enzyme A-subunit PTS1 and binding/transport B-subunit. After receptor-mediated endocytosis, PT reaches the endoplasmic reticulum from where unfolded PTS1 is transported to the cytosol. PTS1 ADP-ribosylates G-protein α-subunits resulting in increased cAMP signaling. Here, a role of target cell chaperones Hsp90, Hsp70, cyclophilins and FK506-binding proteins for cytosolic PTS1-uptake is demonstrated. PTS1 specifically and directly interacts with chaperones in vitro and in cells. Specific pharmacological chaperone inhibition protects CHO-K1, human primary airway basal cells and a fully differentiated airway epithelium from PT-intoxication by reducing intracellular PTS1-amounts without affecting cell binding or enzyme activity. PT is internalized by human airway epithelium secretory but not ciliated cells and leads to increase of apical surface liquid. Cyclophilin-inhibitors reduced leukocytosis in infant mouse model of pertussis, indicating their promising potential for developing novel therapeutic strategies against whooping cough.
Collapse
Affiliation(s)
- Katharina Ernst
- Institute of Pharmacology and Toxicology, University of Ulm Medical Center, Ulm, Germany.
| | - Ann-Katrin Mittler
- Institute of Pharmacology and Toxicology, University of Ulm Medical Center, Ulm, Germany
| | | | - Carolin Kling
- Institute of Pharmacology and Toxicology, University of Ulm Medical Center, Ulm, Germany
| | - Nina Eberhardt
- Institute of Pharmacology and Toxicology, University of Ulm Medical Center, Ulm, Germany
| | - Anna Anastasia
- Institute of Pharmacology and Toxicology, University of Ulm Medical Center, Ulm, Germany
| | - Michael Sonnabend
- Institute of Pharmacology and Toxicology, University of Ulm Medical Center, Ulm, Germany
| | - Robin Lochbaum
- Institute of General Physiology, University of Ulm, Ulm, Germany
| | - Jan Wirsching
- Institute of Pharmacology and Toxicology, University of Ulm Medical Center, Ulm, Germany
| | - Moona Sakari
- Institute of Biomedicine, Research Unit for Infection and Immunity, University of Turku, Turku, Finland
| | - Arto T Pulliainen
- Institute of Biomedicine, Research Unit for Infection and Immunity, University of Turku, Turku, Finland
| | - Ciaran Skerry
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Nicholas H Carbonetti
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Manfred Frick
- Institute of General Physiology, University of Ulm, Ulm, Germany
| | - Holger Barth
- Institute of Pharmacology and Toxicology, University of Ulm Medical Center, Ulm, Germany.
| |
Collapse
|
12
|
Intracellular Trafficking and Translocation of Pertussis Toxin. Toxins (Basel) 2019; 11:toxins11080437. [PMID: 31349590 PMCID: PMC6723225 DOI: 10.3390/toxins11080437] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Accepted: 07/24/2019] [Indexed: 12/25/2022] Open
Abstract
Pertussis toxin (PT) is a multimeric complex of six proteins. The PTS1 subunit is an ADP-ribosyltransferase that inactivates the alpha subunit of heterotrimeric Gi/o proteins. The remaining PT subunits form a pentamer that positions PTS1 in and above the central cavity of the triangular structure. Adhesion of this pentamer to glycoprotein or glycolipid conjugates on the surface of a target cell leads to endocytosis of the PT holotoxin. Vesicle carriers then deliver the holotoxin to the endoplasmic reticulum (ER) where PTS1 dissociates from the rest of the toxin, unfolds, and exploits the ER-associated degradation pathway for export to the cytosol. Refolding of the cytosolic toxin allows it to regain an active conformation for the disruption of cAMP-dependent signaling events. This review will consider the intracellular trafficking of PT and the order-disorder-order transitions of PTS1 that are essential for its cellular activity.
Collapse
|
13
|
Scanlon K, Skerry C, Carbonetti N. Role of Major Toxin Virulence Factors in Pertussis Infection and Disease Pathogenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1183:35-51. [PMID: 31376138 DOI: 10.1007/5584_2019_403] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Bordetella pertussis produces several toxins that affect host-pathogen interactions. Of these, the major toxins that contribute to pertussis infection and disease are pertussis toxin, adenylate cyclase toxin-hemolysin and tracheal cytotoxin. Pertussis toxin is a multi-subunit protein toxin that inhibits host G protein-coupled receptor signaling, causing a wide array of effects on the host. Adenylate cyclase toxin-hemolysin is a single polypeptide, containing an adenylate cyclase enzymatic domain coupled to a hemolysin domain, that primarily targets phagocytic cells to inhibit their antibacterial activities. Tracheal cytotoxin is a fragment of peptidoglycan released by B. pertussis that elicits damaging inflammatory responses in host cells. This chapter describes these three virulence factors of B. pertussis, summarizing background information and focusing on the role of each toxin in infection and disease pathogenesis, as well as their role in pertussis vaccination.
Collapse
Affiliation(s)
- Karen Scanlon
- Department of Microbiology & Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Ciaran Skerry
- Department of Microbiology & Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Nicholas Carbonetti
- Department of Microbiology & Immunology, University of Maryland School of Medicine, Baltimore, MD, USA.
| |
Collapse
|
14
|
Acquaye-Seedah E, Huang Y, Sutherland JN, DiVenere AM, Maynard JA. Humanised monoclonal antibodies neutralise pertussis toxin by receptor blockade and reduced retrograde trafficking. Cell Microbiol 2018; 20:e12948. [PMID: 30152075 PMCID: PMC6519169 DOI: 10.1111/cmi.12948] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Revised: 08/02/2018] [Accepted: 08/20/2018] [Indexed: 12/12/2022]
Abstract
Pertussis toxin (PTx) is a major protective antigen produced by Bordetella pertussis that is included in all current acellular vaccines. Of several well‐characterized monoclonal antibodies binding this toxin, the humanised hu1B7 and hu11E6 antibodies are highly protective in multiple in vitro and in vivo assays. In this study, we determine the molecular mechanisms of protection mediated by these antibodies. Neither antibody directly binds the B. pertussis bacterium nor supports antibody‐dependent complement cytotoxicity. Both antibodies, either individually or as a cocktail, form multivalent complexes with soluble PTx that bind the FcγRIIb receptor more tightly than antibody alone, suggesting that the antibodies may accelerate PTx clearance via immune complex formation. However, a receptor binding assay and cellular imaging indicate that the main mechanism used by hu11E6 is competitive inhibition of PTx binding to its cellular receptor. In contrast, the main hu1B7 neutralising mechanism appears to be inhibition of PTx internalisation and retrograde trafficking. We assessed the effects of hu1B7 on PTx retrograde trafficking in CHO‐K1 cells using quantitative immunofluorescence microscopy. In the absence of hu1B7 or after incubation with an isotype control antibody, PTx colocalizes to organelles in a manner consistent with retrograde transport. However, after preincubation with hu1B7, PTx appears restricted to the membrane surface with colocalization to organelles associated with retrograde transport significantly reduced. Together, these data support a model whereby hu11E6 and hu1B7 interfere with PTx receptor binding and PTx retrograde trafficking, respectively.
Collapse
Affiliation(s)
- Edith Acquaye-Seedah
- Department of Biochemistry, The University of Texas at Austin, Austin, Texas.,Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas
| | - Yimin Huang
- Department of Cell and Molecular Biology, The University of Texas at Austin, Austin, Texas.,Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas
| | - Jamie N Sutherland
- Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas
| | - Andrea M DiVenere
- Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas
| | - Jennifer A Maynard
- Department of Biochemistry, The University of Texas at Austin, Austin, Texas.,Department of Cell and Molecular Biology, The University of Texas at Austin, Austin, Texas.,Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas
| |
Collapse
|
15
|
Pharmacological Cyclophilin Inhibitors Prevent Intoxication of Mammalian Cells with Bordetella pertussis Toxin. Toxins (Basel) 2018; 10:toxins10050181. [PMID: 29723951 PMCID: PMC5983237 DOI: 10.3390/toxins10050181] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 04/18/2018] [Accepted: 04/23/2018] [Indexed: 11/17/2022] Open
Abstract
The Bordetella pertussis toxin (PT) is one important virulence factor causing the severe childhood disease whooping cough which still accounted for approximately 63,000 deaths worldwide in children in 2013. PT consists of PTS1, the enzymatically active (A) subunit and a non-covalently linked pentameric binding/transport (B) subunit. After endocytosis, PT takes a retrograde route to the endoplasmic reticulum (ER), where PTS1 is released into the cytosol. In the cytosol, PTS1 ADP-ribosylates inhibitory alpha subunits of trimeric GTP-binding proteins (Giα) leading to increased cAMP levels and disturbed signalling. Here, we show that the cyclophilin (Cyp) isoforms CypA and Cyp40 directly interact with PTS1 in vitro and that Cyp inhibitors cyclosporine A (CsA) and its tailored non-immunosuppressive derivative VK112 both inhibit intoxication of CHO-K1 cells with PT, as analysed in a morphology-based assay. Moreover, in cells treated with PT in the presence of CsA, the amount of ADP-ribosylated Giα was significantly reduced and less PTS1 was detected in the cytosol compared to cells treated with PT only. The results suggest that the uptake of PTS1 into the cytosol requires Cyps. Therefore, CsA/VK112 represent promising candidates for novel therapeutic strategies acting on the toxin level to prevent the severe, life-threatening symptoms caused by PT.
Collapse
|
16
|
Thermal Unfolding of the Pertussis Toxin S1 Subunit Facilitates Toxin Translocation to the Cytosol by the Mechanism of Endoplasmic Reticulum-Associated Degradation. Infect Immun 2016; 84:3388-3398. [PMID: 27647866 DOI: 10.1128/iai.00732-16] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 09/10/2016] [Indexed: 11/20/2022] Open
Abstract
Pertussis toxin (PT) moves from the host cell surface to the endoplasmic reticulum (ER) by retrograde vesicular transport. The catalytic PTS1 subunit dissociates from the rest of the toxin in the ER and then shifts to a disordered conformation which may trigger its export to the cytosol through the quality control mechanism of ER-associated degradation (ERAD). Functional roles for toxin instability and ERAD in PTS1 translocation have not been established. We addressed these issues with the use of a surface plasmon resonance system to quantify the cytosolic pool of PTS1 from intoxicated cells. Only 3% of surface-associated PTS1 reached the host cytosol after 3 h of toxin exposure. This represented, on average, 38,000 molecules of cytosolic PTS1 per cell. Cells treated with a proteasome inhibitor contained larger quantities of cytosolic PTS1. Stabilization of the dissociated PTS1 subunit with chemical chaperones inhibited toxin export to the cytosol and blocked PT intoxication. ERAD-defective cell lines likewise exhibited reduced quantities of cytosolic PTS1 and PT resistance. These observations identify the unfolding of dissociated PTS1 as a trigger for its ERAD-mediated translocation to the cytosol.
Collapse
|