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Barlow AM, Tingvoll S, Gover E, Schock A, Finlay D. Botulism in Two Juvenile Wild Red Foxes (Vulpes vulpes) in Somerset, England, UK. J Wildl Dis 2024; 60:229-231. [PMID: 37897305 DOI: 10.7589/jwd-d-23-00049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 09/20/2023] [Indexed: 10/30/2023]
Abstract
Two juvenile red foxes (Vulpes vulpes) were euthanased because of severe nervous signs and paralysis. Detailed postmortem examinations were carried out with bacteriology, histology, and Clostridium botulinum toxin screening, which confirmed botulism as the cause of the clinical signs.
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Affiliation(s)
- Alexander M Barlow
- Wildlife Network for Diseases Surveillance, Rookham Cottage, Dursdon Drove, Wells, Somerset, England BA5 3AW, UK
- University of Bristol, Bristol Veterinary School, Langford Campus, England BS40 5DU, UK
| | - Sarah Tingvoll
- Secret World Wildlife Rescue, New Rd, Highbridge, Somerset, England TA9 3PZ, UK
| | - Emily Gover
- Vale Vets, 1 Beach Road West, Portishead, England BS20 7HR, UK
| | - Alex Schock
- Animal and Plant Health Agency (APHA) Lasswade, Pathology Department, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, Scotland EH26 0PZ, UK
| | - David Finlay
- Agri-food and Biosciences Institute, Veterinary Sciences Division, Stoney Road, Upper Newtownards Road, Belfast, Northern Ireland BT4 3SD, UK
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2
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Smith TJ, Schill KM, Williamson CHD. Navigating the Complexities Involving the Identification of Botulinum Neurotoxins (BoNTs) and the Taxonomy of BoNT-Producing Clostridia. Toxins (Basel) 2023; 15:545. [PMID: 37755971 PMCID: PMC10535752 DOI: 10.3390/toxins15090545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 08/17/2023] [Accepted: 08/22/2023] [Indexed: 09/28/2023] Open
Abstract
Botulinum neurotoxins are a varied group of protein toxins that share similar structures and modes of activity. They include at least seven serotypes and over forty subtypes that are produced by seven different clostridial species. These bacterial species are not limited strictly to BoNT-producers as neuro-toxigenic and non-neuro-toxigenic members have been identified within each species. The nomenclature surrounding these toxins and associated bacteria has been evolving as new isolations and discoveries have arisen, resulting in challenges in diagnostic reporting, epidemiology and food safety studies, and in the application of therapeutic products. An understanding of the intricacies regarding the nomenclature of BoNTs and BoNT-producing clostridia is crucial for communication that allows for accurate reporting of information that is pertinent to each situation.
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Affiliation(s)
- Theresa J. Smith
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ 86011, USA;
| | - Kristin M. Schill
- Food Research Institute, University of Wisconsin-Madison, Madison, WI 53706, USA;
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3
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Molecular Diversity of BoNT-Producing Clostridia—A Still-Emerging and Challenging Problem. DIVERSITY 2023. [DOI: 10.3390/d15030392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
The diversity of BoNT-producing Clostridia is still a worrying problem for specialists who explore the evolutionary and taxonomic diversity of C. botulinum. It is also a problem for epidemiologists and laboratory staff conducting investigations into foodborne botulism in humans and animals, because their genetic and phenotypic heterogeneity cause complications in choosing the proper analytical tools and in reliably interpreting results. Botulinum neurotoxins (BoNTs) are produced by several bacterial groups that meet all the criteria of distinct species. Despite this, the historical designation of C. botulinum as the one species that produces botulinum toxins is still exploited. New genetic tools such as whole-genome sequencing (WGS) indicate horizontal gene transfer and the occurrence of botulinum gene clusters that are not limited only to Clostridium spp., but also to Gram-negative aerobic species. The literature data regarding the mentioned heterogeneity of BoNT-producing Clostridia indicate the requirement to reclassify C. botulinum species and other microorganisms able to produce BoNTs or possessing botulinum-like gene clusters. The aim of this study was to present the problem of the diversity of BoNT-producing Clostridia over time and new trends toward obtaining a reliable classification of these microorganisms, based on a complex review of the literature.
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4
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Le Bouquin S, Lucas C, Souillard R, Le Maréchal C, Petit K, Kooh P, Jourdan-Da Silva N, Meurens F, Guillier L, Mazuet C. Human and animal botulism surveillance in France from 2008 to 2019. Front Public Health 2022; 10:1003917. [PMID: 36504929 PMCID: PMC9730534 DOI: 10.3389/fpubh.2022.1003917] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 11/08/2022] [Indexed: 11/27/2022] Open
Abstract
Botulism is a human and animal neurological disease caused by the action of bacterial neurotoxins (botulinum toxins) produced by bacteria from the genus Clostridium. This disease induces flaccid paralysis that can result in respiratory paralysis and heart failure. Due to its serious potential impact on public health, botulism is a closely monitored notifiable disease in France through a case-based passive surveillance system. In humans, this disease is rare, with an average of 10 outbreaks reported each year, mainly due to the consumption of contaminated foods. Type B and to a lesser extend type A are responsible for the majority of cases of foodborne botulism. Each year, an average of 30 outbreaks are recorded on poultry farms, about 20 cases in wild birds and about 10 outbreaks in cattle, involving a large number of animals. Mosaic forms C/D and D/C in birds and cattle, respectively, are the predominant types in animals in France. Types C and D have also been observed to a lesser extent in animals. With the exception of botulinum toxin E, which was exceptionally detected throughout the period in wild birds, the types of botulism found in animal outbreaks are different from those identified in human outbreaks over the last ten years in France and no human botulism outbreaks investigated have been linked to animal botulism. In line with the One Health concept, we present the first integrative approach to the routine surveillance of botulism in humans and animals in France.
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Affiliation(s)
- Sophie Le Bouquin
- French Agency for Food, Environmental and Occupational Health & Safety (ANSES), National Reference Laboratory for Avian Botulism, Ploufragan-Plouzané-Niort Laboratory, Ploufragan, France,*Correspondence: Sophie Le Bouquin
| | - Camille Lucas
- French Agency for Food, Environmental and Occupational Health & Safety (ANSES), National Reference Laboratory for Avian Botulism, Ploufragan-Plouzané-Niort Laboratory, Ploufragan, France
| | - Rozenn Souillard
- French Agency for Food, Environmental and Occupational Health & Safety (ANSES), National Reference Laboratory for Avian Botulism, Ploufragan-Plouzané-Niort Laboratory, Ploufragan, France
| | - Caroline Le Maréchal
- French Agency for Food, Environmental and Occupational Health & Safety (ANSES), National Reference Laboratory for Avian Botulism, Ploufragan-Plouzané-Niort Laboratory, Ploufragan, France
| | - Karine Petit
- ANSES, Risk Assessment Department, Maisons-Alfort, France
| | - Pauline Kooh
- ANSES, Risk Assessment Department, Maisons-Alfort, France
| | - Nathalie Jourdan-Da Silva
- Sante Publique France (French Public Health Agency), Direction des Maladies Infectieuses, Saint Maurice, France
| | - François Meurens
- French National Research Institute for Agriculture, Food and Environment (INRAE), Oniris, Unit of Biology, Epidemiology and Risk Analysis in Animal Health (BIOEPAR), Nantes, France,Department of Veterinary Microbiology and Immunology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | | | - Christelle Mazuet
- Institut Pasteur, National Reference Center for Anaerobic Bacteria and Botulism, Université Paris Cité, Paris, France
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5
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Animal botulism in Poland – laboratory and epidemiological investigations. J Vet Res 2022; 66:189-197. [PMID: 35892106 PMCID: PMC9281532 DOI: 10.2478/jvetres-2022-0026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 05/17/2022] [Indexed: 11/20/2022] Open
Abstract
Abstract
Introduction
The aim of the study was to present cases of botulism in animals found in Poland in 2019–2021. The analytical laboratory diagnosis and difficulties that occurred in the interpretation of the results are described.
Material and Methods
From 2019 to 2021, samples of serum, intestinal content, liver, spleen, kidney, faeces, wet feed, dry feed, ensilage, water and mixed samples of internal organs associated with 10 suspected animal botulism cases were sent to the National Veterinary Research Institute. Samples were analysed using a mouse bioassay and culture methods in combination with ntnh and bont gene detection.
Results
Among the ten putative botulism cases, only four (40%) were confirmed in the laboratory on the basis of the detection of botulinum toxin (BoNT) or the ntnh or bont genes. The remaining six (60%) were determined as probable despite observable characteristic clinical signs.
Conclusion
The diagnosis of botulism in animals is a very difficult task, made so by the heterogeneity of Clostridium botulinum strains and possible loss of toxinogenicity during laboratory processing or the potential degradation of toxins. Laboratory diagnosis is a complex and problematic process which should utilise different prescribed methods for specific types of sample.
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Rosa ICCR, Silva DDSE, Leopoldino AGR, Athayde FRFD, Botelho AFM, Dutra IDS, Borsanelli AC. Type C botulism in dogs from rural properties located in Goiânia, Brazil. ARQUIVOS DO INSTITUTO BIOLÓGICO 2022. [DOI: 10.1590/1808-1657000152021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
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Cai S, Kumar R, Singh BR. Clostridial Neurotoxins: Structure, Function and Implications to Other Bacterial Toxins. Microorganisms 2021; 9:2206. [PMID: 34835332 PMCID: PMC8618262 DOI: 10.3390/microorganisms9112206] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/19/2021] [Accepted: 10/19/2021] [Indexed: 01/20/2023] Open
Abstract
Gram-positive bacteria are ancient organisms. Many bacteria, including Gram-positive bacteria, produce toxins to manipulate the host, leading to various diseases. While the targets of Gram-positive bacterial toxins are diverse, many of those toxins use a similar mechanism to invade host cells and exert their functions. Clostridial neurotoxins produced by Clostridial tetani and Clostridial botulinum provide a classical example to illustrate the structure-function relationship of bacterial toxins. Here, we critically review the recent progress of the structure-function relationship of clostridial neurotoxins, including the diversity of the clostridial neurotoxins, the mode of actions, and the flexible structures required for the activation of toxins. The mechanism clostridial neurotoxins use for triggering their activity is shared with many other Gram-positive bacterial toxins, especially molten globule-type structures. This review also summarizes the implications of the molten globule-type flexible structures to other Gram-positive bacterial toxins. Understanding these highly dynamic flexible structures in solution and their role in the function of bacterial toxins not only fills in the missing link of the high-resolution structures from X-ray crystallography but also provides vital information for better designing antidotes against those toxins.
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Affiliation(s)
- Shuowei Cai
- Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth, Dartmouth, MA 02747, USA
| | - Raj Kumar
- Botulinum Research Center, Institute of Advanced Sciences, Dartmouth, MA 02747, USA; (R.K.); (B.R.S.)
| | - Bal Ram Singh
- Botulinum Research Center, Institute of Advanced Sciences, Dartmouth, MA 02747, USA; (R.K.); (B.R.S.)
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8
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A Four-Monoclonal Antibody Combination Potently Neutralizes Multiple Botulinum Neurotoxin Serotypes C and D. Toxins (Basel) 2021; 13:toxins13090641. [PMID: 34564645 PMCID: PMC8472335 DOI: 10.3390/toxins13090641] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 09/02/2021] [Accepted: 09/07/2021] [Indexed: 12/04/2022] Open
Abstract
Human botulism can be caused by botulinum neurotoxin (BoNT) serotypes A to G. Here, we present an antibody-based antitoxin composed of four human monoclonal antibodies (mAbs) against BoNT/C, BoNT/D, and their mosaic toxins. This work built on our success in generating protective mAbs to BoNT /A, B and E serotypes. We generated mAbs from human immune single-chain Fv (scFv) yeast-display libraries and isolated scFvs with high affinity for BoNT/C, BoNT/CD, BoNT/DC and BoNT/D serotypes. We identified four mAbs that bound non-overlapping epitopes on multiple serotypes and mosaic BoNTs. Three of the mAbs underwent molecular evolution to increase affinity. A four-mAb combination provided high-affinity binding and BoNT neutralization of both serotypes and their mosaic toxins. The mAbs have potential utility as therapeutics and as diagnostics capable of recognizing and neutralizing BoNT/C and BoNT/D serotypes and their mosaic toxins. A derivative of the four-antibody combination (NTM-1634) completed a Phase 1 clinical trial (Snow et al., Antimicrobial Agents and Chemotherapy, 2019) with no drug-related serious adverse events.
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9
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Tevell Åberg A, Karlsson I, Hedeland M. Modification and validation of the Endopep-mass spectrometry method for botulinum neurotoxin detection in liver samples with application to samples collected during animal botulism outbreaks. Anal Bioanal Chem 2020; 413:345-354. [PMID: 33119784 PMCID: PMC7806574 DOI: 10.1007/s00216-020-03001-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/29/2020] [Accepted: 10/09/2020] [Indexed: 01/07/2023]
Abstract
Botulinum neurotoxins (BoNTs) are the most potent toxins known and they cause the paralytic disease botulism in humans and animals. In order to diagnose botulism, active BoNT must be detected in biological material. Endopep-MS is a sensitive and selective method for serum samples, based on antibody capture, enzymatic cleavage of target peptides, and detection of cleavage products using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS). In many cases of animal botulism, serum samples are not available or they do not contain detectable amounts of BoNT and liver sampling is an alternative for postmortem examinations. However, the Endopep-MS method is impaired by the inherent protease activity of liver samples. In the presented study, the Endopep-MS method has been successfully modified and validated for analysis of cattle, horse, and avian liver samples, introducing a combination of a salt washing step and a protease inhibitor cocktail. These modifications resulted in a substantial decrease in interfering signals and increase in BoNT-specific signals. This led to a substantial improvement in sensitivity for especially BoNT-C and C/D which are among the most prominent serotypes for animal botulism. Botulism was diagnosed with the new method in liver samples from dead cattle and birds from outbreaks in Sweden. Graphical Abstract.
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Affiliation(s)
- Annica Tevell Åberg
- Department of Chemistry, Environment, and Feed Hygiene, National Veterinary Institute (SVA), 751 89, Uppsala, Sweden.,Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry, Faculty of Pharmacy, Uppsala University, P.O. Box 574, 751 23, Uppsala, Sweden
| | - Ida Karlsson
- Department of Chemistry, Environment, and Feed Hygiene, National Veterinary Institute (SVA), 751 89, Uppsala, Sweden.,Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry, Faculty of Pharmacy, Uppsala University, P.O. Box 574, 751 23, Uppsala, Sweden
| | - Mikael Hedeland
- Department of Chemistry, Environment, and Feed Hygiene, National Veterinary Institute (SVA), 751 89, Uppsala, Sweden. .,Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry, Faculty of Pharmacy, Uppsala University, P.O. Box 574, 751 23, Uppsala, Sweden.
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10
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Shao JW, Ruan XD, Qin XC, Yan J, Zhang YZ. Metatranscriptomics reveals that the death of a Mongolian wild ass was caused by Clostridium botulinum in Inner Mongolia, China. J Vet Diagn Invest 2020; 32:287-290. [PMID: 32065061 DOI: 10.1177/1040638720905314] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Clostridium botulinum is an important pathogen that causes botulism in humans and animals worldwide. C. botulinum group III strains, which produce a single toxin of type C or D or a chimeric toxin of type C/D or D/C, are responsible for botulism in a wide range of animal species including cattle and birds. We used unbiased high-throughput RNA sequencing (i.e., metatranscriptomics) to identify a strain of group III C. botulinum from a deceased Mongolian wild ass (Equus hemionus). The strain was closely related to some European strains. Genetic analysis of the recovered bacterial sequences showed that the C. botulinum strain identified might represent a type C/D strain of group III. Infection by C. botulinum producing the mosaic toxin of type C/D is the most likely cause of the death of the wild ass.
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Affiliation(s)
- Jian-Wei Shao
- Department of Zoonosis, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, China (Shao, Qin, Zhang).,Department of Medical Microbiology and Parasitology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China (Shao, Yan).,Academy of Forest Inventory and Planning, National Forestry and Grassland Administration, Chaoyang, Beijing, China (Ruan)
| | - Xiang-Dong Ruan
- Department of Zoonosis, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, China (Shao, Qin, Zhang).,Department of Medical Microbiology and Parasitology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China (Shao, Yan).,Academy of Forest Inventory and Planning, National Forestry and Grassland Administration, Chaoyang, Beijing, China (Ruan)
| | - Xin-Cheng Qin
- Department of Zoonosis, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, China (Shao, Qin, Zhang).,Department of Medical Microbiology and Parasitology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China (Shao, Yan).,Academy of Forest Inventory and Planning, National Forestry and Grassland Administration, Chaoyang, Beijing, China (Ruan)
| | - Jie Yan
- Department of Zoonosis, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, China (Shao, Qin, Zhang).,Department of Medical Microbiology and Parasitology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China (Shao, Yan).,Academy of Forest Inventory and Planning, National Forestry and Grassland Administration, Chaoyang, Beijing, China (Ruan)
| | - Yong-Zhen Zhang
- Department of Zoonosis, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, China (Shao, Qin, Zhang).,Department of Medical Microbiology and Parasitology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China (Shao, Yan).,Academy of Forest Inventory and Planning, National Forestry and Grassland Administration, Chaoyang, Beijing, China (Ruan)
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11
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Zaragoza NE, Orellana CA, Moonen GA, Moutafis G, Marcellin E. Vaccine Production to Protect Animals Against Pathogenic Clostridia. Toxins (Basel) 2019; 11:E525. [PMID: 31514424 PMCID: PMC6783934 DOI: 10.3390/toxins11090525] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 08/26/2019] [Accepted: 08/28/2019] [Indexed: 12/19/2022] Open
Abstract
Clostridium is a broad genus of anaerobic, spore-forming, rod-shaped, Gram-positive bacteria that can be found in different environments all around the world. The genus includes human and animal pathogens that produce potent exotoxins that cause rapid and potentially fatal diseases responsible for countless human casualties and billion-dollar annual loss to the agricultural sector. Diseases include botulism, tetanus, enterotoxemia, gas gangrene, necrotic enteritis, pseudomembranous colitis, blackleg, and black disease, which are caused by pathogenic Clostridium. Due to their ability to sporulate, they cannot be eradicated from the environment. As such, immunization with toxoid or bacterin-toxoid vaccines is the only protective method against infection. Toxins recovered from Clostridium cultures are inactivated to form toxoids, which are then formulated into multivalent vaccines. This review discusses the toxins, diseases, and toxoid production processes of the most common pathogenic Clostridium species, including Clostridiumbotulinum, Clostridiumtetani, Clostridiumperfringens, Clostridiumchauvoei, Clostridiumsepticum, Clostridiumnovyi and Clostridiumhemolyticum.
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Affiliation(s)
- Nicolas E. Zaragoza
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Brisbane, QLD 4072, Australia; (N.E.Z.); (C.A.O.)
| | - Camila A. Orellana
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Brisbane, QLD 4072, Australia; (N.E.Z.); (C.A.O.)
| | - Glenn A. Moonen
- Zoetis, 45 Poplar Road, Parkville VIC 3052, Australia; (G.A.M.); (G.M.)
| | - George Moutafis
- Zoetis, 45 Poplar Road, Parkville VIC 3052, Australia; (G.A.M.); (G.M.)
| | - Esteban Marcellin
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Brisbane, QLD 4072, Australia; (N.E.Z.); (C.A.O.)
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12
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Davies JR, Liu SM, Acharya KR. Variations in the Botulinum Neurotoxin Binding Domain and the Potential for Novel Therapeutics. Toxins (Basel) 2018; 10:toxins10100421. [PMID: 30347838 PMCID: PMC6215321 DOI: 10.3390/toxins10100421] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 10/11/2018] [Accepted: 10/18/2018] [Indexed: 01/23/2023] Open
Abstract
Botulinum neurotoxins (BoNTs) are categorised into immunologically distinct serotypes BoNT/A to /G). Each serotype can also be further divided into subtypes based on differences in amino acid sequence. BoNTs are ~150 kDa proteins comprised of three major functional domains: an N-terminal zinc metalloprotease light chain (LC), a translocation domain (HN), and a binding domain (HC). The HC is responsible for targeting the BoNT to the neuronal cell membrane, and each serotype has evolved to bind via different mechanisms to different target receptors. Most structural characterisations to date have focussed on the first identified subtype within each serotype (e.g., BoNT/A1). Subtype differences within BoNT serotypes can affect intoxication, displaying different botulism symptoms in vivo, and less emphasis has been placed on investigating these variants. This review outlines the receptors for each BoNT serotype and describes the basis for the highly specific targeting of neuronal cell membranes. Understanding receptor binding is of vital importance, not only for the generation of novel therapeutics but also for understanding how best to protect from intoxication.
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Affiliation(s)
- Jonathan R Davies
- Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, UK.
| | - Sai Man Liu
- Ipsen Bioinnovation Limited, Abingdon OX14 4RY, UK.
| | - K Ravi Acharya
- Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, UK.
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13
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Chellapandi P, Prisilla A. PCR-based molecular diagnosis of botulism (types C and D) outbreaks in aquatic birds. ANN MICROBIOL 2018. [DOI: 10.1007/s13213-018-1390-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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15
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Brunt J, van Vliet AHM, van den Bos F, Carter AT, Peck MW. Diversity of the Germination Apparatus in Clostridium botulinum Groups I, II, III, and IV. Front Microbiol 2016; 7:1702. [PMID: 27840626 PMCID: PMC5083711 DOI: 10.3389/fmicb.2016.01702] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 10/12/2016] [Indexed: 01/17/2023] Open
Abstract
Clostridium botulinum is a highly dangerous pathogen that forms very resistant endospores that are ubiquitous in the environment, and which, under favorable conditions germinate to produce vegetative cells that multiply and form the exceptionally potent botulinum neurotoxin. To improve the control of botulinum neurotoxin-forming clostridia, it is important to understand the mechanisms involved in spore germination. Here we present models for spore germination in C. botulinum based on comparative genomics analyses, with C. botulinum Groups I and III sharing similar pathways, which differ from those proposed for C. botulinum Groups II and IV. All spores germinate in response to amino acids interacting with a germinant receptor, with four types of germinant receptor identified [encoded by various combinations of gerA, gerB, and gerC genes (gerX)]. There are three gene clusters with an ABC-like configuration; ABC [gerX1], ABABCB [gerX2] and ACxBBB [gerX4], and a single CA-B [gerX3] gene cluster. Subtypes have been identified for most germinant receptor types, and the individual GerX subunits of each cluster show similar grouping in phylogenetic trees. C. botulinum Group I contained the largest variety of gerX subtypes, with three gerX1, three gerX2, and one gerX3 subtypes, while C. botulinum Group III contained two gerX1 types and one gerX4. C. botulinum Groups II and IV contained a single germinant receptor, gerX3 and gerX1, respectively. It is likely that all four C. botulinum Groups include a SpoVA channel involved in dipicolinic acid release. The cortex-lytic enzymes present in C. botulinum Groups I and III appear to be CwlJ and SleB, while in C. botulinum Groups II and IV, SleC appears to be important.
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Affiliation(s)
- Jason Brunt
- Gut Health and Food Safety, Institute of Food ResearchNorwich, UK
| | - Arnoud H. M. van Vliet
- Gut Health and Food Safety, Institute of Food ResearchNorwich, UK
- School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of SurreyGuildford, UK
| | | | - Andrew T. Carter
- Gut Health and Food Safety, Institute of Food ResearchNorwich, UK
| | - Michael W. Peck
- Gut Health and Food Safety, Institute of Food ResearchNorwich, UK
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16
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Hansbauer EM, Skiba M, Endermann T, Weisemann J, Stern D, Dorner MB, Finkenwirth F, Wolf J, Luginbühl W, Messelhäußer U, Bellanger L, Woudstra C, Rummel A, Fach P, Dorner BG. Detection, differentiation, and identification of botulinum neurotoxin serotypes C, CD, D, and DC by highly specific immunoassays and mass spectrometry. Analyst 2016; 141:5281-97. [PMID: 27353114 DOI: 10.1039/c6an00693k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Botulinum neurotoxin (BoNT) serotypes C and D and their mosaic variants CD and DC cause severe cases of botulism in animal husbandry and wildlife. Epidemiological data on the exact serotype or toxin variant causing outbreaks are rarely available, mainly because of their high sequence identity and the lack of fast and specific screening tools to detect and differentiate the four similar toxins. To fill this gap, we developed four highly specific sandwich enzyme-linked immunosorbent assays (ELISAs) able to detect and differentiate botulinum neurotoxins type BoNT/C, D, CD, and DC based on four distinct combinations of specific monoclonal antibodies targeting both conserved and divergent subdomains of the four toxins. Here, highly sensitive detection with detection limits between 2 and 24 pg mL(-1) was achieved. The ELISAs were extensively validated and results were compared with data obtained by quantitative real-time PCR using a panel of Clostridium botulinum strains, real sample materials from veterinary botulism outbreaks, and non-BoNT-producing Clostridia. Additionally, in order to verify the results obtained by ELISA screening, the new monoclonal antibodies were used for BoNT enrichment and subsequent detection (i) on a functional level by endopeptidase mass spectrometry (Endopep-MS) assays and (ii) on a protein sequence level by LC-MS/MS spectrometry. Based on all technical information gathered in the validation study, the four differentiating ELISAs turned out to be highly reliable screening tools for the rapid analysis of veterinary botulism cases and should aid future field investigations of botulism outbreaks and the acquisition of epidemiological data.
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Affiliation(s)
- Eva-Maria Hansbauer
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute (RKI), Berlin, Germany.
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Chatla K, Gaunt PS, Petrie-Hanson L, Ford L, Hanson LA. Zebrafish Sensitivity to Botulinum Neurotoxins. Toxins (Basel) 2016; 8:toxins8050132. [PMID: 27153088 PMCID: PMC4885047 DOI: 10.3390/toxins8050132] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 04/12/2016] [Accepted: 04/20/2016] [Indexed: 02/03/2023] Open
Abstract
Botulinum neurotoxins (BoNT) are the most potent known toxins. The mouse LD50 assay is the gold standard for testing BoNT potency, but is not sensitive enough to detect the extremely low levels of neurotoxin that may be present in the serum of sensitive animal species that are showing the effects of BoNT toxicity, such as channel catfish affected by visceral toxicosis of catfish. Since zebrafish are an important animal model for diverse biomedical and basic research, they are readily available and have defined genetic lines that facilitate reproducibility. This makes them attractive for use as an alternative bioassay organism. The utility of zebrafish as a bioassay model organism for BoNT was investigated. The 96 h median immobilizing doses of BoNT/A, BoNT/C, BoNT/E, and BoNT/F for adult male Tübingen strain zebrafish (0.32 g mean weight) at 25 °C were 16.31, 124.6, 4.7, and 0.61 picograms (pg)/fish, respectively. These findings support the use of the zebrafish-based bioassays for evaluating the presence of BoNT/A, BoNT/E, and BoNT/F. Evaluating the basis of the relatively high resistance of zebrafish to BoNT/C and the extreme sensitivity to BoNT/F may reveal unique functional patterns to the action of these neurotoxins.
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Affiliation(s)
- Kamalakar Chatla
- Department of Basic Science, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
| | - Patricia S Gaunt
- Thad Cochran National Warmwater Aquaculture Center, College of Veterinary Medicine, Mississippi State University, Stoneville, MS 38756, USA.
| | - Lora Petrie-Hanson
- Department of Basic Science, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
| | - Lorelei Ford
- Department of Basic Science, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
| | - Larry A Hanson
- Department of Basic Science, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
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Authors' response. Am J Orthod Dentofacial Orthop 2016; 149:443-5. [DOI: 10.1016/j.ajodo.2016.01.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 01/21/2016] [Accepted: 01/21/2016] [Indexed: 01/09/2023]
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Montgomery VA, Ahmed SA, Olson MA, Mizanur RM, Stafford RG, Roxas-Duncan VI, Smith LA. Ex vivo inhibition of Clostridium botulinum neurotoxin types B, C, E, and F by small molecular weight inhibitors. Toxicon 2015; 98:12-9. [PMID: 25707753 DOI: 10.1016/j.toxicon.2015.02.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 02/06/2015] [Accepted: 02/19/2015] [Indexed: 11/28/2022]
Abstract
Two small molecular weight inhibitors, compounds CB7969312 and CB7967495, that displayed inhibition of botulinum neurotoxin serotype A in a previous study, were evaluated for inhibition of botulinum neurotoxin serotypes B, C, E, and F. The small molecular weight inhibitors were assessed by molecular modeling, UPLC-based peptide cleavage assay; and an ex vivo assay, the mouse phrenic nerve - hemidiaphragm assay (MPNHDA). While both compounds were inhibitors of botulinum neurotoxin (BoNT) serotypes B, C, and F in the MPNHDA, compound CB7969312 was effective at lower molar concentrations than compound CB7967495. However, compound CB7967495 was significantly more effective at preventing BoNTE intoxication than compound CB7969312. In the UPLC-based peptide cleavage assay, CB7969312 was also more effective against LcC. Both compounds inhibited BoNTE, but not BoNTF, LcE, or LcF in the UPLC-based peptide cleavage assay. Molecular modeling studies predicted that both compounds would be effective inhibitors of BoNTs B, C, E, and F. But CB7967495 was predicted to be a more effective inhibitor of the four serotypes (B, C, E, and F) than CB7969312. This is the first report of a small molecular weight compound that inhibits serotypes B, C, E, and F in the ex vivo assay.
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Affiliation(s)
- Vicki A Montgomery
- U.S. Army Medical Research Institute of Infectious Diseases, Division of Molecular and Translational Sciences, 1425 Porter St. Ft Detrick, Frederick, MD, USA.
| | - S Ashraf Ahmed
- U.S. Army Medical Research Institute of Infectious Diseases, Division of Molecular and Translational Sciences, 1425 Porter St. Ft Detrick, Frederick, MD, USA.
| | - Mark A Olson
- U.S. Army Medical Research Institute of Infectious Diseases, Division of Molecular and Translational Sciences, 1425 Porter St. Ft Detrick, Frederick, MD, USA.
| | - Rahman M Mizanur
- U.S. Army Medical Research Institute of Infectious Diseases, Biosurety Division, 1430 Veterans Dr, Ft Detrick, Frederick, MD, USA(1).
| | - Robert G Stafford
- U.S. Army Medical Research Institute of Infectious Diseases, Division of Molecular and Translational Sciences, 1425 Porter St. Ft Detrick, Frederick, MD, USA.
| | - Virginia I Roxas-Duncan
- U.S. Army Medical Research Institute of Infectious Diseases, Biosurety Division, 1430 Veterans Dr, Ft Detrick, Frederick, MD, USA(1).
| | - Leonard A Smith
- Medical Countermeasures Technology, U.S. Army Medical Research and Material Command, 1425 Porter St. Ft Detrick, Frederick, MD, USA.
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Anniballi F, Auricchio B, Woudstra C, Fach P, Fiore A, Skarin H, Bano L, Segerman B, Knutsson R, De Medici D. Multiplex real-time PCR for detecting and typing Clostridium botulinum group III organisms and their mosaic variants. Biosecur Bioterror 2014; 11 Suppl 1:S207-14. [PMID: 23971808 DOI: 10.1089/bsp.2012.0084] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Botulism is a neuroparalytic disease that can occur in all warm-blooded animals, birds, and fishes. The disease in animals is mainly caused by toxins produced by Clostridium botulinum strains belonging to group III, although outbreaks due to toxins produced by group I and II organisms have been recognized. Group III strains are capable of producing botulinum toxins of type C, D, and C/D and D/C mosaic variants. Definitive diagnosis of animal botulism is made by combining clinical findings with laboratory investigations. Detection of toxins in clinical specimens and feed is the gold standard for laboratory diagnosis. Since toxins may be degraded by organisms contained in the gastrointestinal tract or may be present at levels below the detection limit, the recovery of C. botulinum from sick animal specimens is consistent for laboratory confirmation. In this article we report the development and in-house validation of a new multiplex real-time PCR for detecting and typing the neurotoxin genes found in C. botulinum group III organisms. Validation procedures have been carried out according to ISO 16140, using strains and samples recovered from cases of animal botulism in Italy and France.
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21
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Anniballi F, Fiore A, Löfström C, Skarin H, Auricchio B, Woudstra C, Bano L, Segerman B, Koene M, Båverud V, Hansen T, Fach P, Tevell Aberg A, Hedeland M, Olsson Engvall E, De Medici D. Management of animal botulism outbreaks: from clinical suspicion to practical countermeasures to prevent or minimize outbreaks. Biosecur Bioterror 2014; 11 Suppl 1:S191-9. [PMID: 23971806 DOI: 10.1089/bsp.2012.0089] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Botulism is a severe neuroparalytic disease that affects humans, all warm-blooded animals, and some fishes. The disease is caused by exposure to toxins produced by Clostridium botulinum and other botulinum toxin-producing clostridia. Botulism in animals represents a severe environmental and economic concern because of its high mortality rate. Moreover, meat or other products from affected animals entering the food chain may result in a public health problem. To this end, early diagnosis is crucial to define and apply appropriate veterinary public health measures. Clinical diagnosis is based on clinical findings eliminating other causes of neuromuscular disorders and on the absence of internal lesions observed during postmortem examination. Since clinical signs alone are often insufficient to make a definitive diagnosis, laboratory confirmation is required. Botulinum antitoxin administration and supportive therapies are used to treat sick animals. Once the diagnosis has been made, euthanasia is frequently advisable. Vaccine administration is subject to health authorities' permission, and it is restricted to a small number of animal species. Several measures can be adopted to prevent or minimize outbreaks. In this article we outline all phases of management of animal botulism outbreaks occurring in wet wild birds, poultry, cattle, horses, and fur farm animals.
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Affiliation(s)
- Fabrizio Anniballi
- Fabrizio Anniballi, CLT, is a Laboratory Technician; Alfonsina Fiore, PhD, is a Researcher; Bruna Auricchio, CLT, is a Laboratory Technician; and Dario De Medici, PhD, is Senior Researcher, all at Istituto Superiore di Sanità (ISS), Department of Veterinary Public Health and Food Safety, Rome, Italy. Charlotta Löfström, PhD, is an Assistant Professor, and Trine Hansen, MSc, is a PhD student, both at the National Food Institute, Technical University of Denmark (DTU), Søborg, Denmark. Hanna Skarin, MSc, is a Research Assistant; Bo Segerman, PhD, is is a Researcher; Viveca Båverud, PhD, is Associate Professor; Eva Olsson Engvall, PhD, is Associate Professor; all in the Department of Bacteriology, National Veterinary Institute (SVA), Uppsala, Sweden, and Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden. Cédric Woudstra, MSc, is an Engineer, and Patrick Fach, PhD, is Head of the High Throughput qPCR Platform IdentyPath, both at the French Agency for Food, Environmental and Occupational Health Safety (ANSES), Food Safety Laboratory, Maisons-Alfort, France. Luca Bano, PhD, is Veterinary Officer, Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe), Veterinary Diagnostic Laboratory of Treviso, Treviso, Italy. Miriam Koene, DVM, is a Scientist, Central Veterinary Institute of Wageningen University and Research Centre (CVI) , Lelystad, the Netherlands. Annica Tevell Åberg, PhD, is a Senior Researcher, and Mikael Hedeland, PhD, is Associate Professor and Deputy Head of the Department, Department of Chemistry, Environment and Feed Hygiene, National Veterinary Institute (SVA), Uppsala, Sweden
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Burgain A, Rochard A, Trollet C, Mazuet C, Popoff MR, Escriou V, Scherman D, Bigey P. DNA electroporation in rabbits as a method for generation of high-titer neutralizing antisera: examples of the botulinum toxins types A, B, and E. Hum Vaccin Immunother 2013; 9:2147-56. [PMID: 23877030 DOI: 10.4161/hv.25192] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Raising high titer antibodies in animals is usually performed by protein immunization, which requires the long and sometimes difficult step of production of the recombinant protein. DNA immunization is an alternative to recombinant proteins, only requiring the building of an eukaryotic expression plasmid. Thanks to efficient DNA delivery techniques such as in vivo electroporation, DNA vaccination has proven useful the last few years. In this work, we have shown that it is possible to raise very high antibody titers in rabbit by DNA electroporation of an antigen encoding plasmid in the skeletal muscle with the right set of electrodes and rabbit strain. In a model of botulinum toxins types A and E, the neutralizing titers obtained after three treatments were high enough to fit the European Pharmacopeia, while it did not for type B toxin. Furthermore, the raised antibodies have high avidity and are suitable for in vitro and in vivo immunodetection of proteins.
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Affiliation(s)
- Aurore Burgain
- Université Paris Descartes; Paris, France; ENSCP Chimie ParisTech; Paris, France; CNRS UMR8151; Paris, France; Inserm U1022; Paris, France
| | - Alice Rochard
- Université Paris Descartes; Paris, France; ENSCP Chimie ParisTech; Paris, France; CNRS UMR8151; Paris, France; Inserm U1022; Paris, France
| | - Capucine Trollet
- Université Paris Descartes; Paris, France; ENSCP Chimie ParisTech; Paris, France; CNRS UMR8151; Paris, France; Inserm U1022; Paris, France
| | | | | | - Virginie Escriou
- Université Paris Descartes; Paris, France; ENSCP Chimie ParisTech; Paris, France; CNRS UMR8151; Paris, France; Inserm U1022; Paris, France
| | - Daniel Scherman
- Université Paris Descartes; Paris, France; ENSCP Chimie ParisTech; Paris, France; CNRS UMR8151; Paris, France; Inserm U1022; Paris, France
| | - Pascal Bigey
- Université Paris Descartes; Paris, France; ENSCP Chimie ParisTech; Paris, France; CNRS UMR8151; Paris, France; Inserm U1022; Paris, France
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24
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Woudstra C, Skarin H, Anniballi F, Auricchio B, De Medici D, Bano L, Drigo I, Hansen T, Löfström C, Hamidjaja R, van Rotterdam BJ, Koene M, Bäyon-Auboyer MH, Buffereau JP, Fach P. Validation of a real-time PCR based method for detection of Clostridium botulinum types C, D and their mosaic variants C-D and D-C in a multicenter collaborative trial. Anaerobe 2013; 22:31-7. [PMID: 23669132 DOI: 10.1016/j.anaerobe.2013.05.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Revised: 04/19/2013] [Accepted: 05/01/2013] [Indexed: 11/29/2022]
Abstract
Two real-time PCR arrays based on the GeneDisc(®) cycler platform (Pall-GeneDisc Technologies) were evaluated in a multicenter collaborative trial for their capacity to specifically detect and discriminate Clostridium botulinum types C, D and their mosaic variants C-D and D-C that are associated with avian and mammalian botulism. The GeneDisc(®) arrays developed as part of the DG Home funded European project 'AnibioThreat' were highly sensitive and specific when tested on pure isolates and naturally contaminated samples (mostly clinical specimen from avian origin). Results of the multicenter collaborative trial involving eight laboratories in five European Countries (two laboratories in France, Italy and The Netherlands, one laboratory in Denmark and Sweden), using DNA extracts issued from 33 pure isolates and 48 naturally contaminated samples associated with animal botulism cases, demonstrated the robustness of these tests. Results showed a concordance among the eight laboratories of 99.4%-100% for both arrays. The reproducibility of the tests was high with a relative standard deviation ranging from 1.1% to 7.1%. Considering the high level of agreement achieved between the laboratories these PCR arrays constitute robust and suitable tools for rapid detection of C. botulinum types C, D and mosaic types C-D and D-C. These are the first tests for C. botulinum C and D that have been evaluated in a European multicenter collaborative trial.
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Affiliation(s)
- Cedric Woudstra
- French Agency for Food, Environmental and Occupational Health and Safety (Anses), Food Safety Laboratory, 23 Av du Général De Gaulle, Fr-94706 Maisons-Alfort, France
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25
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Zhang Y, Gardberg AS, Edwards TE, Sankaran B, Robinson H, Varnum SM, Buchko GW. Structural insights into the functional role of the Hcn sub-domain of the receptor-binding domain of the botulinum neurotoxin mosaic serotype C/D. Biochimie 2013; 95:1379-85. [PMID: 23523511 DOI: 10.1016/j.biochi.2013.03.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Accepted: 03/05/2013] [Indexed: 12/13/2022]
Abstract
Botulinum neurotoxin (BoNT), the causative agent of the deadly neuroparalytic disease botulism, is the most poisonous protein known for humans. Produced by different strains of the anaerobic bacterium Clostridium botulinum, BoNT effects cellular intoxication via a multistep mechanism executed by the three modules of the activated protein. Endocytosis, the first step of cellular intoxication, is triggered by the ~50 kDa, heavy-chain receptor-binding domain (HCR) that is specific for a ganglioside and a protein receptor on neuronal cell surfaces. This dual receptor recognition mechanism between BoNT and the host cell's membrane is well documented and occurs via specific intermolecular interactions with the C-terminal sub-domain, Hcc, of BoNT-HCR. The N-terminal sub-domain of BoNT-HCR, Hcn, comprises ~50% of BoNT-HCR and adopts a β-sheet jelly roll fold. While suspected in assisting cell surface recognition, no unambiguous function for the Hcn sub-domain in BoNT has been identified. To obtain insights into the potential function of the Hcn sub-domain in BoNT, the first crystal structure of a BoNT with an organic ligand bound to the Hcn sub-domain has been obtained. Here, we describe the crystal structure of BoNT/CD-HCR determined at 1.70 Å resolution with a tetraethylene glycol (PG4) moiety bound in a hydrophobic cleft between β-strands in the β-sheet jelly roll fold of the Hcn sub-domain. The PG4 moiety is completely engulfed in the cleft, making numerous hydrophilic (Y932, S959, W966, and D1042) and hydrophobic (S935, W977, L979, N1013, and I1066) contacts with the protein's side chain and backbone that may mimic in vivo interactions with the phospholipid membranes on neuronal cell surfaces. A sulfate ion was also observed bound to residues T1176, D1177, K1196, and R1243 in the Hcc sub-domain of BoNT/CD-HCR. In the crystal structure of a similar protein, BoNT/D-HCR, a sialic acid molecule was observed bound to the equivalent residues suggesting that residues T1176, D1177, K1196, and R1243 in BoNT/CD may play a role in ganglioside binding.
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Affiliation(s)
- Yanfeng Zhang
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
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Zhang Y, Lou J, Jenko KL, Marks JD, Varnum SM. Simultaneous and sensitive detection of six serotypes of botulinum neurotoxin using enzyme-linked immunosorbent assay-based protein antibody microarrays. Anal Biochem 2012; 430:185-92. [PMID: 22935296 DOI: 10.1016/j.ab.2012.08.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 07/27/2012] [Accepted: 08/21/2012] [Indexed: 11/18/2022]
Abstract
Botulinum neurotoxins (BoNTs), produced by Clostridium botulinum, are a group of seven (A-G) immunologically distinct proteins and cause the paralytic disease botulism. These toxins are the most poisonous substances known to humans and are potential bioweapon agents. Therefore, it is necessary to develop highly sensitive assays for the detection of BoNTs in both clinical and environmental samples. In the current study, we have developed an enzyme-linked immunosorbent assay (ELISA)-based protein antibody microarray for the sensitive and simultaneous detection of BoNT serotypes A, B, C, D, E, and F. With engineered high-affinity antibodies, the BoNT assays have sensitivities in buffer ranging from 1.3fM (0.2pg/ml) to 14.7fM (2.2pg/ml). Using clinical and food matrices (serum and milk), the microarray is capable of detecting BoNT serotypes A to F to similar levels as in standard buffer. Cross-reactivity between assays for individual serotype was also analyzed. These simultaneous, rapid, and sensitive assays have the potential to measure botulinum toxins in a high-throughput manner in complex clinical, food, and environmental samples.
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Affiliation(s)
- Yanfeng Zhang
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
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27
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Neurotoxin gene profiling of clostridium botulinum types C and D native to different countries within Europe. Appl Environ Microbiol 2012; 78:3120-7. [PMID: 22344654 DOI: 10.1128/aem.07568-11] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Clostridium botulinum types C and D, as well as their mosaic variants C-D and D-C, are associated with avian and mammalian botulism. This study reports on the development of low-density macroarrays based on the GeneDisc cycler platform (Pall-GeneDisc Technologies) applied to the simultaneous detection of the C. botulinum subtypes C, C-D, D, and D-C. The limit of detection of the PCR assays was 38 fg of total DNA, corresponding to 15 genome copies. Artificially contaminated samples of cecum showed a limit of detection below 50 spores/g. The tests were performed with a large variety of bacterial strains, including C. botulinum types C (n = 12), C-D (n = 29), D (n = 5), and D-C (n = 10), other botulinum neurotoxin (BoNT)-producing Clostridium strains (n = 20), non-BoNT-producing clostridia (n = 20), and other bacterial species (n = 23), and showed a high specificity. These PCR assays were compared to previously published real-time PCRs for the detection of C. botulinum in 292 samples collected from cases of botulism events in four European regions. The majority of the samples originated from wild birds (n = 108), poultry (n = 60), and bovines (n = 56). Among the 292 samples, 144 were positive for either the bont/C-D or the bont/D-C gene by using the GeneDisc arrays. The reliability of the results tallied to 97.94%. Interestingly, only BoNT mosaics, types C-D and D-C, were found in naturally contaminated samples whatever their animal origin and their geographical location. Further investigations should now be performed in order to check that mosaic types dominate in Europe and that acquisition of mosaic types helps in survival or adaptation to particular niche.
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Hedeland M, Moura H, Båverud V, Woolfitt AR, Bondesson U, Barr JR. Confirmation of botulism in birds and cattle by the mouse bioassay and Endopep-MS. J Med Microbiol 2011; 60:1299-1305. [PMID: 21566090 DOI: 10.1099/jmm.0.031179-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
There have been several outbreaks of botulism among poultry and wild birds in Sweden in recent years. The National Veterinary Institute of Sweden (SVA) has identified botulinum neurotoxin (BoNT)/C1 or the mosaic BoNT/C1D using the mouse bioassay. This is believed to be the first report on the application of the Endopep mass spectrometry (Endopep-MS) method to selected clinical animal (serum and liver) samples and a feed sample that had previously given positive test results with the mouse bioassay. In the mouse bioassay eight of the eleven samples were found to be neutralized by both BoNT/C1 and /D antitoxins; the other three were neutralized only by BoNT/C1 antitoxin, but the mice showed a prolonged survival time when the samples had been treated with /D antitoxin. The Endopep-MS analysis, on the other hand, demonstrated only BoNT/C1 activity for all eleven samples. This suggests that at least eight of the samples were of the chimeric toxin type BoNT/C1D, where the enzymically active site is identical to that of BoNT/C1, while other parts of the protein contain sequences of BoNT/D. This is the first step of a cross-validation between the established mouse bioassay and the Endopep-MS of serotypes BoNT/C1 and /C1D. Endopep-MS is concluded to have potential as an attractive alternative to the mouse bioassay.
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Affiliation(s)
- Mikael Hedeland
- Uppsala University, Division of Analytical Pharmaceutical Chemistry, Biomedical Centre, PO Box 574, SE-751 23 Uppsala, Sweden.,National Veterinary Institute (SVA), Department of Chemistry, Environment and Feed Hygiene, SE-751 89 Uppsala, Sweden
| | - Hercules Moura
- Centers for Disease Control and Prevention, NCEH/DLS, 4770 Buford Hwy NE, Atlanta, GA 30341-3724, USA
| | - Viveca Båverud
- National Veterinary Institute (SVA), Department of Bacteriology, SE-751 89 Uppsala, Sweden
| | - Adrian R Woolfitt
- Centers for Disease Control and Prevention, NCEH/DLS, 4770 Buford Hwy NE, Atlanta, GA 30341-3724, USA
| | - Ulf Bondesson
- Uppsala University, Division of Analytical Pharmaceutical Chemistry, Biomedical Centre, PO Box 574, SE-751 23 Uppsala, Sweden.,National Veterinary Institute (SVA), Department of Chemistry, Environment and Feed Hygiene, SE-751 89 Uppsala, Sweden
| | - John R Barr
- Centers for Disease Control and Prevention, NCEH/DLS, 4770 Buford Hwy NE, Atlanta, GA 30341-3724, USA
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Zhang Y, Buchko GW, Qin L, Robinson H, Varnum SM. Crystal structure of the receptor binding domain of the botulinum C-D mosaic neurotoxin reveals potential roles of lysines 1118 and 1136 in membrane interactions. Biochem Biophys Res Commun 2010; 404:407-12. [PMID: 21130733 DOI: 10.1016/j.bbrc.2010.11.134] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Accepted: 11/29/2010] [Indexed: 01/22/2023]
Abstract
The botulinum neurotoxins (BoNTs) produced by different strains of the bacterium Clostridium botulinum are responsible for the disease botulism and include a group of immunologically distinct serotypes (A, B, E, and F) that are considered to be the most lethal natural proteins known for humans. Two BoNT serotypes, C and D, while rarely associated with human infection, are responsible for deadly botulism outbreaks afflicting animals. Also associated with animal infections is the BoNT C-D mosaic protein (BoNT/CD), a BoNT subtype that is essentially a hybrid of the BoNT/C (∼two-third) and BoNT/D (∼one-third) serotypes. While the amino acid sequence of the heavy chain receptor binding (HCR) domain of BoNT/CD (BoNT/CD-HCR) is very similar to the corresponding amino acid sequence of BoNT/D, BoNT/CD-HCR binds synaptosome membranes better than BoNT/D-HCR. To obtain structural insights for the different membrane binding properties, the crystal structure of BoNT/CD-HCR (S867-E1280) was determined at 1.56 Å resolution and compared to previously reported structures for BoNT/D-HCR. Overall, the BoNT/CD-HCR structure is similar to the two sub-domain organization observed for other BoNT HCRs: an N-terminal jellyroll barrel motif and a C-terminal β-trefoil fold. Comparison of the structure of BoNT/CD-HCR with BoNT/D-HCR indicates that K1118 has a similar structural role as the equivalent residue, E1114, in BoNT/D-HCR, while K1136 has a structurally different role than the equivalent residue, G1132, in BoNT/D-HCR. Lysine-1118 forms a salt bridge with E1247 and may enhance membrane interactions by stabilizing the putative membrane binding loop (K1240-N1248). Lysine-1136 is observed on the surface of the protein. A sulfate ion bound to K1136 may mimic a natural interaction with the negatively changed phospholipid membrane surface. Liposome-binding experiments demonstrate that BoNT/CD-HCR binds phosphatidylethanolamine liposomes more tightly than BoNT/D-HCR.
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Affiliation(s)
- Yanfeng Zhang
- Cell Biology and Biochemistry Group, Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
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Zhang Y, Gao X, Qin L, Buchko GW, Robinson H, Varnum SM. High-level expression, purification, crystallization and preliminary X-ray crystallographic studies of the receptor-binding domain of botulinum neurotoxin serotype D. Acta Crystallogr Sect F Struct Biol Cryst Commun 2010; 66:1610-3. [PMID: 21139207 DOI: 10.1107/s1744309110039874] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2010] [Accepted: 10/06/2010] [Indexed: 11/10/2022]
Abstract
Botulinum neurotoxins (BoNTs) are highly toxic proteins for humans and animals that are responsible for the deadly neuroparalytic disease botulism. Here, details of the expression and purification of the receptor-binding domain (HCR) of BoNT/D in Escherichia coli are presented. Using a codon-optimized cDNA, BoNT/D_HCR was expressed at a high level (150-200 mg per litre of culture) in the soluble fraction. Following a three-step purification protocol, very pure (>98%) BoNT/D_HCR was obtained. The recombinant BoNT/D_HCR was crystallized and the crystals diffracted to 1.65 Å resolution. The crystals belonged to space group P2(1)2(1)2(1), with unit-cell parameters a=60.8, b=89.7, c=93.9 Å. Preliminary crystallographic data analysis revealed the presence of one molecule in the asymmetric unit.
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Affiliation(s)
- Yanfeng Zhang
- Cell Biology and Biochemistry Group, Pacific Northwest National Laboratory, Richland, WA 99352, USA
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Myllykoski J, Lindström M, Bekema E, Pölönen I, Korkeala H. Fur animal botulism hazard due to feed. Res Vet Sci 2010; 90:412-8. [PMID: 20663530 DOI: 10.1016/j.rvsc.2010.06.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Revised: 06/01/2010] [Accepted: 06/22/2010] [Indexed: 11/17/2022]
Abstract
To assess the botulism hazard in fur animal feed production, 236 fur animal feed components and feed samples were analysed for Clostridium botulinum by detecting BoNT-encoding genes (botA, botB, botC, botE or botF) by PCR and for sulphite-reducing clostridia (SRC) by iron sulphite agar. The quality of the hazard analysis of critical control points (HACCP) -based in-house control system (IHCS) was evaluated with respect to botulism risk in feed plants (n=32). The overall prevalence of C. botulinum was 13% in different feed components and 5% in feed. The estimated MPN count of C. botulinum in feed components was 6.4 × 10(3)/kg at the highest and was shown to poorly correlate with SRC count. The critical control points in IHCSs were variable, and control limits were improperly set in most feed-producing plants. C. botulinum possesses a persistent safety hazard for fur animals by feed production, and control practices should be reassessed.
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Affiliation(s)
- J Myllykoski
- Department of Food and Environmental Hygiene, Faculty of Veterinary Medicine, University of Helsinki, Finland.
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Lindström M, Myllykoski J, Sivelä S, Korkeala H. Clostridium botulinumin Cattle and Dairy Products. Crit Rev Food Sci Nutr 2010; 50:281-304. [DOI: 10.1080/10408390802544405] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Generation of high-titer neutralizing antibodies against botulinum toxins A, B, and E by DNA electrotransfer. Infect Immun 2009; 77:2221-9. [PMID: 19237523 DOI: 10.1128/iai.01269-08] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Botulinum neurotoxins are known to be among the most toxic known substances. They produce severe paralysis by preventing the release of acetylcholine at the neuromuscular junction. Thus, new strategies for efficient production of safe and effective anti-botulinum neurotoxin antisera have been a high priority. Here we describe the use of DNA electrotransfer into the skeletal muscle to enhance antiserum titers against botulinum toxin serotypes A, B, and E in mice. We treated animals with codon-optimized plasmid DNA encoding the nontoxic but highly immunogenic C-terminal heavy chain fragment of the toxin. By employing both codon optimization and the electrotransfer procedure, the immune response and corresponding neutralizing antiserum titers were markedly increased. The cellular localization of the antigen and the immunization regimens were also shown to increase neutralizing titers to >100 IU/ml. This study demonstrates that DNA electrotransfer is an effective procedure for raising neutralizing antiserum titers to remarkably high levels.
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New highly specific botulinum type C1 endopeptidase immunoassays utilising SNAP25 or Syntaxin substrates. J Immunol Methods 2009; 343:21-7. [PMID: 19176217 DOI: 10.1016/j.jim.2009.01.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2008] [Revised: 01/07/2009] [Accepted: 01/08/2009] [Indexed: 11/22/2022]
Abstract
Botulinum neurotoxins contain proteases that cleave specific intra-neural proteins essential for neurotransmitter release. Toxin types A, C1 and E intra-cellularly cleave SNAP25 and/or Syntaxin (type C1 only) resulting in a flaccid paralysis. Although highly sensitive, robust in vitro endopeptidase immunoassays have been developed for some serotypes, an endopeptidase immunoassay for type C1 has not previously been described. The current studies utilised solid phase synthesized SNAP25(137-206) peptide substrate, and a new specific antibody to the SNAP25(191-198) octapeptide epitope that becomes exposed following cleavage by type C1 toxin. The highly specific nature of the detecting antibody was illustrated by the failure of anti-SNAP25(191-198) to recognise the type A cleavage product which differs by just one amino acid residue. Conversely, anti-SNAP25(190-197), which recognises the type A cleavage product, fails to cross react with the type C1 toxin cleavage product. Utilising Syntaxin(232-266) peptide substrate, and a specific antibody to the cleavage product epitope, Syntaxin(254-261), it was also possible to develop an endopeptidase immunoassay. Assay sensitivities allowed the detection of less than 0.1 LD(50)/ml (25 pg/ml) of type C1 haemagglutinin-complexed toxin. The assay failed to detect toxin serotypes A, B, D, E, F or G and therefore also provides an alternative highly specific in vitro identity test. In the absence of trypsin inhibitors, the assay is also capable of detecting 2 pg/ml of trypsin activity, or trypsin like contaminants. These new immunoassays will therefore provide highly specific tools for monitoring botulinum toxin light chain endopeptidase activity and serotype identity.
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Affiliation(s)
- Michael W Peck
- Institute of Food Research, Norwich Research Park, Colney, Norwich, UK
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Type C bovine botulism outbreak due to carcass contaminated non-acidified silage. Epidemiol Infect 2008; 137:284-93. [PMID: 18606025 DOI: 10.1017/s0950268808000939] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The first reported bovine botulism outbreak in Finland is described. Nine out of 90 cattle on a dairy farm died after being fed non-acidified silage contaminated by animal carcasses. Type C botulinum neurotoxin gene was detected in one heifer by polymerase chain reaction (PCR) and the neurotoxin was detected by the mouse bioassay. Clostridium botulinum type C was isolated from liver samples. The isolated strain was identified with amplified fragment length polymorphism (AFLP) analysis as group III C. botulinum. To our knowledge, this is the first time that a type C bovine botulism outbreak has been diagnosed by PCR and confirmed by subsequent isolation and AFLP identification of the disease strain. The importance of the acidification process in silage production to inhibit C. botulinum toxin production in silage and thus to prevent further botulism outbreaks is emphasized. Nevertheless, preformed toxin in the carcass is not destroyed by acid.
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Microbiological risk assessment in feedingstuffs for food-producing animals - Scientific Opinion of the Panel on Biological Hazards. EFSA J 2008; 6:720. [PMID: 37213857 PMCID: PMC10193654 DOI: 10.2903/j.efsa.2008.720] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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Affiliation(s)
- Eric A Johnson
- Department of Bacteriology, Food Research Institute, University of Wisconsin, Madison, WI, USA.
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Abstract
Foodborne botulism is caused by consumption of preformed botulinum neurotoxin, with as little as 30 ng of neurotoxin being potentially lethal. Consumption of minute quantities of neurotoxin-containing food can result in botulism. In view of the severity of foodborne botulism, it is essential that new foods be developed safely without an increase in incidence of this disease. Minimally heated, chilled foods are a relatively new type of food, sales of which are currently increasing by about 10% per annum. These products meet consumer demand for high-quality foods that require little preparation time. Their safety and quality depends on mild heat treatment, chilled storage, restricted shelf life and sometimes on intrinsic properties of the foods. The principal microbiological hazard is nonproteolytic Clostridium botulinum, and there is a concern that this may become an emerging issue. A considerable amount of research and development over the last 15 years has underpinned the safe production of commercial, minimally heated, chilled foods with respect to foodborne botulism, and it is essential that safe food continues to be developed. In particular, the desire to use lighter heat processes and a longer shelf life presents a challenge that will only be met by significant developments in quantitative microbiological food safety.
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Affiliation(s)
- M W Peck
- Institute of Food Research, Norwich Research Park, Colney, Norwich, UK.
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Webb RP, Smith TJ, Wright PM, Montgomery VA, Meagher MM, Smith LA. Protection with recombinant Clostridium botulinum C1 and D binding domain subunit (Hc) vaccines against C and D neurotoxins. Vaccine 2007; 25:4273-82. [PMID: 17395341 DOI: 10.1016/j.vaccine.2007.02.081] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2006] [Revised: 02/21/2007] [Accepted: 02/21/2007] [Indexed: 11/22/2022]
Abstract
Recombinant botulinum Hc (rBoNT Hc) vaccines for serotypes C1 and D were produced in the yeast Pichia pastoris and used to determine protection against four distinct BoNT C and D toxin subtypes. Mice were vaccinated with rBoNT/C1 Hc, rBoNT/D Hc, or with a combination of both vaccines and challenged with BoNT C1, D, C/D, or D/C toxin. Mice receiving monovalent vaccinations were partially or completely protected against homologous toxin and not protected against heterologous toxin. Bivalent vaccine candidates completely survived challenges from all toxins except D/C toxin. These results indicate the recombinant C1 and D Hc vaccines are not only effective in a monovalent formula but offer complete protection against both parental and C/D mosaic toxin and partial protection against D/C mosaic toxin when delivered as a bivalent vaccine.
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MESH Headings
- Amino Acid Sequence
- Animals
- Bacterial Vaccines/genetics
- Bacterial Vaccines/immunology
- Base Sequence
- Botulinum Toxins/genetics
- Botulinum Toxins/immunology
- Botulism/immunology
- Botulism/prevention & control
- Clostridium botulinum/genetics
- Clostridium botulinum/immunology
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- Disease Models, Animal
- Enzyme-Linked Immunosorbent Assay
- Female
- Mice
- Molecular Sequence Data
- Pichia/genetics
- Pichia/metabolism
- Sequence Alignment
- Sequence Analysis, DNA
- Survival Analysis
- Vaccines, Subunit/genetics
- Vaccines, Subunit/immunology
- Vaccines, Subunit/isolation & purification
- Vaccines, Synthetic/genetics
- Vaccines, Synthetic/immunology
- Vaccines, Synthetic/isolation & purification
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Affiliation(s)
- Robert P Webb
- Integrated Toxicology Division, United States Army Medical Research Institute for Infectious Diseases, 1425 Porter Street, Frederick, MD 21702, United States
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