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Pillai SP, Hill KK, Gans J, Smith TJ. Real-time PCR assays that detect genes for botulinum neurotoxin A-G subtypes. Front Microbiol 2024; 15:1382056. [PMID: 38873139 PMCID: PMC11169944 DOI: 10.3389/fmicb.2024.1382056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Accepted: 04/22/2024] [Indexed: 06/15/2024] Open
Abstract
The role of Real-Time PCR assays for surveillance and rapid screening for pathogens is garnering more and more attention because of its versatility and ease of adoption. The goal of this study was to design, test, and evaluate Real-Time TaqMan PCR assays for the detection of botulinum neurotoxin (bont/A-G) genes from currently recognized BoNT subtypes. Assays were computationally designed and then laboratory tested for sensitivity and specificity using DNA preparations containing bont genes from 82 target toxin subtypes, including nine bivalent toxin types; 31 strains representing other clostridial species; and an extensive panel that consisted of DNA from a diverse set of prokaryotic (bacterial) and eukaryotic (fungal, protozoan, plant, and animal) species. In addition to laboratory testing, the assays were computationally evaluated using in silico analysis for their ability to detect bont gene sequences from recently identified toxin subtypes. Seventeen specific assays (two for each of the bont/C, bont/D, bont/E, and bont/G subtypes and three for each of the bont/A, bont/B, and bont/F subtypes) were designed and evaluated for their ability to detect bont genes encoding multiple subtypes from all seven serotypes. These assays could provide an additional tool for the detection of botulinum neurotoxins in clinical, environmental and food samples that can complement other existing methods used in clinical diagnostics, regulatory, public health, and research laboratories.
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Affiliation(s)
- Segaran P. Pillai
- Office of the Commissioner, Food and Drug Administration, Department of Health and Human Services, Silver Spring, MD, United States
| | - Karen K. Hill
- Los Alamos National Laboratory, Bioscience Division, Los Alamos, NM, United States
| | - Jason Gans
- Los Alamos National Laboratory, Bioscience Division, Los Alamos, NM, United States
| | - Theresa J. Smith
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, United States
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2
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Valdezate S, Carrasco G, Medina MJ, Garrido N, del Pino S, Valiente M, Pallarés MP, Villalon P. Exploring the genetic background of the botulism neurotoxin BoNT/B2 in Spain. Microbiol Spectr 2023; 11:e0238023. [PMID: 37750689 PMCID: PMC10581064 DOI: 10.1128/spectrum.02380-23] [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: 06/06/2023] [Accepted: 08/13/2023] [Indexed: 09/27/2023] Open
Abstract
To determine whether the neurotoxin BoNT/B2 causing botulism in Spain is clonal, the genetic diversity and phylogenetic relationships of Clostridium botulinum from food-borne episodes and infant cases of the condition were explored. The botulinum toxin gene (bont) subtype, the variable region of the flagellin gene (flaVR), and a seven-gene multi-locus sequence type were examined by sequencing 37 BoNT-positive cultures obtained over the period 2010 to 2022. Out of 37 botulism events, 16 food-borne episodes and 16 infant cases were associated with bont/b2. Eight bont/b2 alleles were detected [nucleotide distance range 0.0259-0.415%, Hunter and Gaston discrimination index (HGDI) 0.71]. The most common bont/b2 allele corresponded to that of strain Prevot 25 NCASE and its single and double locus variations (87.5%). Four known flaVR types were identified (HGDI 0.79), along with one previously unknown (flaVR-15). Sixteen sequence types (STs) (HGDI 0.89) were recorded including seven new STs (ST164-ST170; 10 new alleles) and five new STs (ST171-ST175; with new allele combinations) were also noted. Correlations among some STs and flaVR types were seen. Overall, the present results show that the combined analysis of bont/b2-flaVR-ST at the nucleotide level could be used to track botulism events in Spain. The neurotoxin BoNT/B2 has largely been responsible for human botulism in Spain. The polymorphism analysis of bont/b2, flaVR typing, and sequence type determinations, revealed a wide variety of clones to be responsible for human botulism, ruling out a common source of acquisition. IMPORTANCE Botulism, a potentially fatal disease, is classically characterized by a symmetrical descending flaccid paralysis, which if left untreated can lead to respiratory failure and death. Botulinum neurotoxin (BoNT), produced by certain species of Clostridium, is the most potent biological toxin known, and the direct cause of botulism. This study characterizes the acquisition in Spain of two forms of botulism, i.e., food-borne and infant botulism, which are largely caused by the main neurotoxin BoNT/B2. Polymorphism analysis of the bont/b2 gene, typing of the flagellin variable region sequence (flaVR), and multilocus sequence typing, were used to explore the genetic background of Clostridium botulinum group I. To our knowledge, this is the first phylogenetic and typing study of botulism undertaken in Spain.
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Affiliation(s)
- Sylvia Valdezate
- Reference and Research Laboratory for Taxonomy, National Centre of Microbiology, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Gema Carrasco
- Reference and Research Laboratory for Taxonomy, National Centre of Microbiology, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - María J. Medina
- Reference and Research Laboratory for Taxonomy, National Centre of Microbiology, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Noelia Garrido
- Reference and Research Laboratory for Taxonomy, National Centre of Microbiology, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Silvia del Pino
- Reference and Research Laboratory for Taxonomy, National Centre of Microbiology, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Monica Valiente
- Reference and Research Laboratory for Taxonomy, National Centre of Microbiology, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - María P. Pallarés
- Veterinary Unit, Animal Department, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Pilar Villalon
- Reference and Research Laboratory for Taxonomy, National Centre of Microbiology, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
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Munir MT, Mtimet N, Guillier L, Meurens F, Fravalo P, Federighi M, Kooh P. Physical Treatments to Control Clostridium botulinum Hazards in Food. Foods 2023; 12:foods12081580. [PMID: 37107375 PMCID: PMC10137509 DOI: 10.3390/foods12081580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 03/30/2023] [Accepted: 04/04/2023] [Indexed: 04/29/2023] Open
Abstract
Clostridium botulinum produces Botulinum neurotoxins (BoNTs), causing a rare but potentially deadly type of food poisoning called foodborne botulism. This review aims to provide information on the bacterium, spores, toxins, and botulisms, and describe the use of physical treatments (e.g., heating, pressure, irradiation, and other emerging technologies) to control this biological hazard in food. As the spores of this bacterium can resist various harsh environmental conditions, such as high temperatures, the thermal inactivation of 12-log of C. botulinum type A spores remains the standard for the commercial sterilization of food products. However, recent advancements in non-thermal physical treatments present an alternative to thermal sterilization with some limitations. Low- (<2 kGy) and medium (3-5 kGy)-dose ionizing irradiations are effective for a log reduction of vegetative cells and spores, respectively; however, very high doses (>10 kGy) are required to inactivate BoNTs. High-pressure processing (HPP), even at 1.5 GPa, does not inactivate the spores and requires heat combination to achieve its goal. Other emerging technologies have also shown some promise against vegetative cells and spores; however, their application to C. botulinum is very limited. Various factors related to bacteria (e.g., vegetative stage, growth conditions, injury status, type of bacteria, etc.) food matrix (e.g., compositions, state, pH, temperature, aw, etc.), and the method (e.g., power, energy, frequency, distance from the source to target, etc.) influence the efficacy of these treatments against C. botulinum. Moreover, the mode of action of different physical technologies is different, which provides an opportunity to combine different physical treatment methods in order to achieve additive and/or synergistic effects. This review is intended to guide the decision-makers, researchers, and educators in using physical treatments to control C. botulinum hazards.
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Affiliation(s)
- Muhammad Tanveer Munir
- EnvA, Unit of Hygiene, Quality and Food Safety, 94700 Maisons-Alfort, France
- Anses, Laboratory of Food Safety, 94700 Maisons-Alfort, France
| | - Narjes Mtimet
- EnvA, Unit of Hygiene, Quality and Food Safety, 94700 Maisons-Alfort, France
- Anses, Laboratory of Food Safety, 94700 Maisons-Alfort, France
| | | | - François Meurens
- INRAE, Oniris, BIOEPAR, 44307 Nantes, France
- Swine and Poultry Infectious Diseases Research Center, Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, QC J2S 2M2, Canada
| | - Phillipe Fravalo
- Chaire Agroalimentaire du Cnam, Conservatoire des Arts et Métiers, EPN7, 22440 Ploufragan, France
| | - Michel Federighi
- EnvA, Unit of Hygiene, Quality and Food Safety, 94700 Maisons-Alfort, France
- Anses, Laboratory of Food Safety, 94700 Maisons-Alfort, France
| | - Pauline Kooh
- Anses, Unit UERALIM, 94700 Maisons-Alfort, France
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Lin Y, Jiang Y, Gong Z, Wang Y, Jiang M, Chen Q, Li C, Hu Q, Shi X. Investigation and Identification of Food Poisoning Caused by Clostridium botulinum Type B1 in Shenzhen, China. Foodborne Pathog Dis 2022; 19:226-231. [PMID: 35231189 DOI: 10.1089/fpd.2021.0060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Clostridium botulinum produces botulinum neurotoxins (BoNTs), which cause people who ingest them to become seriously ill and sometimes die. In recent years, sporadic food poisoning cases associated with C. botulinum have occurred across the world. In 2016, two men were admitted to our hospital in Shenzhen, China, with foodborne botulism. In this study, we report on these two typical C. botulinum-related food poisoning incidents and the steps taken to identify and characterize the causative pathogen. We characterized the bacterial pathogen isolated from the first patient using cooked meat medium and egg yolk agar bacterial cultures under anaerobic conditions, and morphologically identified the isolate using Gram staining. The in vivo bioassay results in mice showed that the minimum lethal dose of the BoNTs produced by our isolate was 0.001-0.0001 mg/mL (LD50 of the culture was estimated to be 1.5812 mg/kg). Whole genome sequencing (WGS) results showed that the isolate was identified as C. botulinum B1 Okra. The causative strain was successfully isolated from the intestinal lavage fluid collected from the initial patient.
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Affiliation(s)
- Yiman Lin
- Shenzhen Major Infectious Disease Control Key Laboratory, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Yixiang Jiang
- Shenzhen Major Infectious Disease Control Key Laboratory, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Zelong Gong
- School of Public Health, Southern Medical University, Guangzhou, China
| | - Yanli Wang
- The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Min Jiang
- Shenzhen Major Infectious Disease Control Key Laboratory, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Qiongcheng Chen
- Shenzhen Major Infectious Disease Control Key Laboratory, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Chunlian Li
- Shenzhen Major Infectious Disease Control Key Laboratory, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Qinghua Hu
- Shenzhen Major Infectious Disease Control Key Laboratory, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Xiaolu Shi
- Shenzhen Major Infectious Disease Control Key Laboratory, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
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Wentz TG, Tremblay BJM, Bradshaw M, Doxey AC, Sharma SK, Sauer JD, Pellett S. Endogenous CRISPR-Cas Systems in Group I Clostridium botulinum and Clostridium sporogenes Do Not Directly Target the Botulinum Neurotoxin Gene Cluster. Front Microbiol 2022; 12:787726. [PMID: 35222299 PMCID: PMC8865420 DOI: 10.3389/fmicb.2021.787726] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 12/27/2021] [Indexed: 12/28/2022] Open
Abstract
Most strains of proteolytic group I Clostridium botulinum (G1 C. botulinum) and some strains of Clostridium sporogenes possess genes encoding botulinum neurotoxin (BoNT), a potent neuroparalytic agent. Within G1 C. botulinum, conserved bont gene clusters of three major toxin serotypes (bont/A/B/F) can be found on conjugative plasmids and/or within chromosomal pathogenicity islands. CRISPR-Cas systems enable site-specific targeting of previously encountered mobile genetic elements (MGE) such as plasmids and bacteriophage through the creation of a spacer library complementary to protospacers within the MGEs. To examine whether endogenous CRISPR-Cas systems restrict the transfer of bont gene clusters across strains we conducted a bioinformatic analysis profiling endogenous CRISPR-Cas systems from 241 G1 C. botulinum and C. sporogenes strains. Approximately 6,200 CRISPR spacers were identified across the strains and Type I-B, III-A/B/D cas genes and CRISPR array features were identified in 83% of the strains. Mapping the predicted spacers against the masked strain and RefSeq plasmid dataset identified 56,000 spacer-protospacer matches. While spacers mapped heavily to targets within bont(+) plasmids, no protospacers were identified within the bont gene clusters. These results indicate the toxin is not a direct target of CRISPR-Cas but the plasmids predominantly responsible for its mobilization are. Finally, while the presence of a CRISPR-Cas system did not reliably indicate the presence or absence of a bont gene cluster, comparative genomics across strains indicates they often occupy the same hypervariable loci common to both species, potentially suggesting similar mechanisms are involved in the acquisition and curation of both genomic features.
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Affiliation(s)
- Travis G. Wentz
- Microbiology Doctoral Training Program, University of Wisconsin–Madison, Madison, WI, United States,Division of Microbiology, Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, MD, United States,Department of Bacteriology, University of Wisconsin–Madison, Madison, WI, United States
| | | | - Marite Bradshaw
- Department of Bacteriology, University of Wisconsin–Madison, Madison, WI, United States
| | - Andrew C. Doxey
- Department of Biology, University of Waterloo, Waterloo, ON, Canada
| | - Shashi K. Sharma
- Division of Microbiology, Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, MD, United States
| | - John-Demian Sauer
- Department of Medical Microbiology and Immunology, University of Wisconsin–Madison, Madison, WI, United States
| | - Sabine Pellett
- Department of Bacteriology, University of Wisconsin–Madison, Madison, WI, United States,*Correspondence: Sabine Pellett,
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Smith TJ, Tian R, Imanian B, Williamson CHD, Johnson SL, Daligault HE, Schill KM. Integration of Complete Plasmids Containing Bont Genes into Chromosomes of Clostridium parabotulinum, Clostridium sporogenes, and Clostridium argentinense. Toxins (Basel) 2021; 13:473. [PMID: 34357945 PMCID: PMC8310154 DOI: 10.3390/toxins13070473] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/30/2021] [Accepted: 07/05/2021] [Indexed: 11/16/2022] Open
Abstract
At least 40 toxin subtypes of botulinum neurotoxins (BoNTs), a heterogenous group of bacterial proteins, are produced by seven different clostridial species. A key factor that drives the diversity of neurotoxigenic clostridia is the association of bont gene clusters with various genomic locations including plasmids, phages and the chromosome. Analysis of Clostridium sporogenes BoNT/B1 strain CDC 1632, C. argentinense BoNT/G strain CDC 2741, and Clostridium parabotulinum BoNT/B1 strain DFPST0006 genomes revealed bont gene clusters within plasmid-like sequences within the chromosome or nested in large contigs, with no evidence of extrachromosomal elements. A nucleotide sequence (255,474 bp) identified in CDC 1632 shared 99.5% identity (88% coverage) with bont/B1-containing plasmid pNPD7 of C. sporogenes CDC 67071; CDC 2741 contig AYSO01000020 (1.1 MB) contained a ~140 kb region which shared 99.99% identity (100% coverage) with plasmid pRSJ17_1 of C. argentinense BoNT/G strain 89G; and DFPST0006 contig JACBDK0100002 (573 kb) contained a region that shared 100% identity (99%) coverage with the bont/B1-containing plasmid pCLD of C. parabotulinum Okra. This is the first report of full-length plasmid DNA-carrying complete neurotoxin gene clusters integrated in three distinct neurotoxigenic species: C. parabotulinum, C. sporogenes and C. argentinense.
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Affiliation(s)
- Theresa J. Smith
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ 86011, USA; (T.J.S.); (C.H.D.W.)
| | - Renmao Tian
- Institute for Food Safety and Health, Illinois Institute of Technology, Bedford Park, IL 60501, USA; (R.T.); (B.I.)
| | - Behzad Imanian
- Institute for Food Safety and Health, Illinois Institute of Technology, Bedford Park, IL 60501, USA; (R.T.); (B.I.)
- Food Science and Nutrition, Illinois Institute of Technology, Chicago, IL 60616, USA
| | - Charles H. D. Williamson
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ 86011, USA; (T.J.S.); (C.H.D.W.)
| | - Shannon L. Johnson
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA; (S.L.J.); (H.E.D.)
| | | | - Kristin M. Schill
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, Bedford Park, IL 60501, USA
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Smith TJ, Williamson CHD, Hill KK, Johnson SL, Xie G, Anniballi F, Auricchio B, Fernández RA, Caballero PA, Keim P, Sahl JW. The Distinctive Evolution of orfX Clostridium parabotulinum Strains and Their Botulinum Neurotoxin Type A and F Gene Clusters Is Influenced by Environmental Factors and Gene Interactions via Mobile Genetic Elements. Front Microbiol 2021; 12:566908. [PMID: 33716993 PMCID: PMC7952441 DOI: 10.3389/fmicb.2021.566908] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 02/08/2021] [Indexed: 12/30/2022] Open
Abstract
Of the seven currently known botulinum neurotoxin-producing species of Clostridium, C. parabotulinum, or C. botulinum Group I, is the species associated with the majority of human botulism cases worldwide. Phylogenetic analysis of these bacteria reveals a diverse species with multiple genomic clades. The neurotoxins they produce are also diverse, with over 20 subtypes currently represented. The existence of different bont genes within very similar genomes and of the same bont genes/gene clusters within different bacterial variants/species indicates that they have evolved independently. The neurotoxin genes are associated with one of two toxin gene cluster types containing either hemagglutinin (ha) genes or orfX genes. These genes may be located within the chromosome or extrachromosomal elements such as large plasmids. Although BoNT-producing C parabotulinum bacteria are distributed globally, they are more ubiquitous in certain specific geographic regions. Notably, northern hemisphere strains primarily contain ha gene clusters while southern hemisphere strains have a preponderance of orfX gene clusters. OrfX C. parabotulinum strains constitute a subset of this species that contain highly conserved bont gene clusters having a diverse range of bont genes. While much has been written about strains with ha gene clusters, less attention has been devoted to those with orfX gene clusters. The recent sequencing of 28 orfX C. parabotulinum strains and the availability of an additional 91 strains for analysis provides an opportunity to compare genomic relationships and identify unique toxin gene cluster characteristics and locations within this species subset in depth. The mechanisms behind the independent processes of bacteria evolution and generation of toxin diversity are explored through the examination of bacterial relationships relating to source locations and evidence of horizontal transfer of genetic material among different bacterial variants, particularly concerning bont gene clusters. Analysis of the content and locations of the bont gene clusters offers insights into common mechanisms of genetic transfer, chromosomal integration, and development of diversity among these genes.
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Affiliation(s)
- Theresa J Smith
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, United States
| | - Charles H D Williamson
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, United States
| | - Karen K Hill
- Los Alamos National Laboratory, Los Alamos, NM, United States
| | | | - Gary Xie
- Los Alamos National Laboratory, Los Alamos, NM, United States
| | - Fabrizio Anniballi
- Department of Food Safety, Nutrition and Veterinary Public Health, National Reference Centre for Botulism, Istituto Superiore di Sanità, Rome, Italy
| | - Bruna Auricchio
- Department of Food Safety, Nutrition and Veterinary Public Health, National Reference Centre for Botulism, Istituto Superiore di Sanità, Rome, Italy
| | - Rafael A Fernández
- Área Microbiología, Departamento de Patología, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Patricia A Caballero
- Área Microbiología, Departamento de Patología, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Paul Keim
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, United States
| | - Jason W Sahl
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, United States
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Brunt J, van Vliet AHM, Carter AT, Stringer SC, Amar C, Grant KA, Godbole G, Peck MW. Diversity of the Genomes and Neurotoxins of Strains of Clostridium botulinum Group I and Clostridium sporogenes Associated with Foodborne, Infant and Wound Botulism. Toxins (Basel) 2020; 12:toxins12090586. [PMID: 32932818 PMCID: PMC7551954 DOI: 10.3390/toxins12090586] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 09/02/2020] [Accepted: 09/08/2020] [Indexed: 12/23/2022] Open
Abstract
Clostridium botulinum Group I and Clostridium sporogenes are closely related bacteria responsible for foodborne, infant and wound botulism. A comparative genomic study with 556 highly diverse strains of C. botulinum Group I and C. sporogenes (including 417 newly sequenced strains) has been carried out to characterise the genetic diversity and spread of these bacteria and their neurotoxin genes. Core genome single-nucleotide polymorphism (SNP) analysis revealed two major lineages; C. botulinum Group I (most strains possessed botulinum neurotoxin gene(s) of types A, B and/or F) and C. sporogenes (some strains possessed a type B botulinum neurotoxin gene). Both lineages contained strains responsible for foodborne, infant and wound botulism. A new C. sporogenes cluster was identified that included five strains with a gene encoding botulinum neurotoxin sub-type B1. There was significant evidence of horizontal transfer of botulinum neurotoxin genes between distantly related bacteria. Population structure/diversity have been characterised, and novel associations discovered between whole genome lineage, botulinum neurotoxin sub-type variant, epidemiological links to foodborne, infant and wound botulism, and geographic origin. The impact of genomic and physiological variability on the botulism risk has been assessed. The genome sequences are a valuable resource for future research (e.g., pathogen biology, evolution of C. botulinum and its neurotoxin genes, improved pathogen detection and discrimination), and support enhanced risk assessments and the prevention of botulism.
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Affiliation(s)
- Jason Brunt
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge CB3 0AS, UK
- Gut Health and Food Safety, Quadram Institute, Norwich Research Park, Norwich NR4 7UQ, UK; (A.T.C.); (S.C.S.)
- Correspondence: (J.B.); (M.W.P.)
| | - Arnoud H. M. van Vliet
- School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7AL, UK;
| | - Andrew T. Carter
- Gut Health and Food Safety, Quadram Institute, Norwich Research Park, Norwich NR4 7UQ, UK; (A.T.C.); (S.C.S.)
| | - Sandra C. Stringer
- Gut Health and Food Safety, Quadram Institute, Norwich Research Park, Norwich NR4 7UQ, UK; (A.T.C.); (S.C.S.)
| | - Corinne Amar
- Gastrointestinal Pathogens Unit, National Infection Service, Public Health England, London NW9 5EQ, UK; (C.A.); (K.A.G.); (G.G.)
| | - Kathie A. Grant
- Gastrointestinal Pathogens Unit, National Infection Service, Public Health England, London NW9 5EQ, UK; (C.A.); (K.A.G.); (G.G.)
| | - Gauri Godbole
- Gastrointestinal Pathogens Unit, National Infection Service, Public Health England, London NW9 5EQ, UK; (C.A.); (K.A.G.); (G.G.)
| | - Michael W. Peck
- Gut Health and Food Safety, Quadram Institute, Norwich Research Park, Norwich NR4 7UQ, UK; (A.T.C.); (S.C.S.)
- Correspondence: (J.B.); (M.W.P.)
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