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Journal ArticleDOI

Dissecting the contributions of Clostridium perfringens type C toxins to lethality in the mouse intravenous injection model.

TL;DR: The results highlight the importance of beta toxin for type C-induced toxemia and surveyed a large collection of type C isolates to determine their toxin-producing abilities.
Abstract: The gram-positive anaerobe Clostridium perfringens produces a large arsenal of toxins that are responsible for histotoxic and enteric infections, including enterotoxemias, in humans and domestic animals. C. perfringens type C isolates, which cause rapidly fatal diseases in domestic animals and enteritis necroticans in humans, contain the genes for alpha toxin (plc), perfringolysin O (pfoA), beta toxin (cpb), and sometimes beta2 toxin (cpb2) and/or enterotoxin (cpe). Due to the economic impact of type C-induced diseases, domestic animals are commonly vaccinated with crude type C toxoid (prepared from inactivated culture supernatants) or bacterin/toxoid vaccines, and it is not clear which toxin(s) present in these vaccines actually elicits the protective immune response. To improve type C vaccines, it would be helpful to assess the contribution of each toxin present in type C supernatants to lethality. To address this issue, we surveyed a large collection of type C isolates to determine their toxin-producing abilities. When late-log-phase vegetative culture supernatants were analyzed by quantitative Western blotting or activity assays, most type C isolates produced at least three lethal toxins, alpha toxin, beta toxin, and perfringolysin O, and several isolates also produced beta2 toxin. In the mouse intravenous injection model, beta toxin was identified as the main lethal factor present in type C late-log-phase culture supernatants. This conclusion was based on monoclonal antibody neutralization studies and regression analyses in which the levels of alpha toxin, beta toxin, perfringolysin O, and beta2 toxin production were compared with lethality. Collectively, our results highlight the importance of beta toxin for type C-induced toxemia.
Citations
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Journal ArticleDOI
TL;DR: It is established that C. perfringens uses chromosomally encoded alpha toxin and perfringolysin O (a pore-forming toxin) during histotoxic infections and this bacterium causes intestinal disease by employing toxins encoded by mobile genetic elements.
Abstract: Clostridium perfringens uses its arsenal of >16 toxins to cause histotoxic and intestinal infections in humans and animals. It has been unclear why this bacterium produces so many different toxins, especially since many target the plasma membrane of host cells. However, it is now established that C. perfringens uses chromosomally encoded alpha toxin (a phospholipase C) and perfringolysin O (a pore-forming toxin) during histotoxic infections. In contrast, this bacterium causes intestinal disease by employing toxins encoded by mobile genetic elements, including C. perfringens enterotoxin, necrotic enteritis toxin B-like, epsilon toxin and beta toxin. Like perfringolysin O, the toxins with established roles in intestinal disease form membrane pores. However, the intestinal disease-associated toxins vary in their target specificity, when they are produced (sporulation vs vegetative growth), and in their sensitivity to intestinal proteases. Producing many toxins with diverse characteristics likely imparts virulence flexibility to C. perfringens so it can cause an array of diseases.

299 citations

Journal ArticleDOI
TL;DR: In this paper, the authors used histopathological examination of brain lesions for diagnosis of type D enterotoxemia, as lesions produced by epsilon toxin in the brains of sheep and goats are pathognomonic for type D. But, although such tests have a presumptive diagnostic value when positive, they cannot be used to rule out a diagnosis of enteroxemia when negative.
Abstract: Clostridium perfringens produces enteric diseases, generically called enterotoxemias, in sheep, goats, and other animals. This microorganism can be a normal inhabitant of the intestine of most animal species, including humans, but when the intestinal environment is altered by sudden changes in diet or other factors, C. perfringens proliferates and produces potent toxins that act locally or are absorbed into the general circulation with usually devastating effects on the host. History, clinical signs, and gross postmortem findings are useful tools for establishing a presumptive diagnosis of clostridial enterotoxemia in sheep and goats. Definitive diagnosis requires laboratory confirmation. Isolation of some types of C. perfringens (e.g., B and C) can be of diagnostic value, but other types (e.g., A) are so commonly found in the intestine of normal animals that isolation is meaningless from a diagnostic point of view. The most accepted criterion in establishing a definitive diagnosis of enterotoxemia is detection of C. perfringens toxins in intestinal contents. Also, histopathological examination of brain is very useful for diagnosis of type D disease, as lesions produced by epsilon toxin in the brains of sheep and goats are pathognomonic for type D enterotoxemia. Ancillary tests, such as measuring urine glucose or observing Gram-stained smears of intestinal mucosa, can be used. However, although such tests have a presumptive diagnostic value when positive, they cannot be used to rule out a diagnosis of enterotoxemia when negative.

213 citations

Journal ArticleDOI
TL;DR: The presence of toxin genes on conjugative plasmids, particularly in association with insertion sequences that may mobilize these toxin genes, likely provides C. perfringens with considerable virulence plasticity and adaptability when it causes diseases originating in the gastrointestinal tract.
Abstract: In both humans and animals, Clostridium perfringens is an important cause of histotoxic infections and diseases originating in the intestines, such as enteritis and enterotoxemia. The virulence of this Gram-positive, anaerobic bacterium is heavily dependent upon its prolific toxin-producing ability. Many of the ∼16 toxins produced by C. perfringens are encoded by large plasmids that range in size from ∼45 kb to ∼140 kb. These plasmid-encoded toxins are often closely associated with mobile elements. A C. perfringens strain can carry up to three different toxin plasmids, with a single plasmid carrying up to three distinct toxin genes. Molecular Koch's postulate analyses have established the importance of several plasmid-encoded toxins when C. perfringens disease strains cause enteritis or enterotoxemias. Many toxin plasmids are closely related, suggesting a common evolutionary origin. In particular, most toxin plasmids and some antibiotic resistance plasmids of C. perfringens share an ∼35-kb region containing a Tn916-related conjugation locus named tcp (transfer of clostridial plasmids). This tcp locus can mediate highly efficient conjugative transfer of these toxin or resistance plasmids. For example, conjugative transfer of a toxin plasmid from an infecting strain to C. perfringens normal intestinal flora strains may help to amplify and prolong an infection. Therefore, the presence of toxin genes on conjugative plasmids, particularly in association with insertion sequences that may mobilize these toxin genes, likely provides C. perfringens with considerable virulence plasticity and adaptability when it causes diseases originating in the gastrointestinal tract.

206 citations

Journal ArticleDOI
01 Apr 2004-Anaerobe
TL;DR: The diagnosis of C. perfringens infections in animals is complex and it is appropriate to rely on a combination of diagnostic techniques rather than one singe test.

169 citations

Journal ArticleDOI
TL;DR: Results indicate that CPB is both required and sufficient for CN3685‐induced enteric pathology, supporting a key role for this toxin in type C intestinal pathogenesis.
Abstract: Summary Clostridium perfringens type C isolates, which cause enteritis necroticans in humans and enteritis and enterotoxaemias of domestic animals, typically produce (at minimum) beta toxin (CPB), alpha toxin (CPA) and perfringolysin O (PFO) during log-phase growth. To assist development of improved vaccines and therapeutics, we evaluated the contribution of these three toxins to the intestinal virulence of type C disease isolate CN3685. Similar to natural type C infection, log-phase vegetative cultures of wild-type CN3685 caused haemorrhagic necrotizing enteritis in rabbit ileal loops. When isogenic toxin null mutants were prepared using TargeTron® technology, even a double cpa/pfoA null mutant of CN3685 remained virulent in ileal loops. However, two independent cpb null mutants were completely attenuated for virulence in this animal model. Complementation of a cpb mutant restored its CPB production and intestinal virulence. Additionally, pre-incubation of wild-type CN3685 with a CPB-neutralizing monoclonal antibody rendered the strain avirulent for causing intestinal pathology. Finally, highly purified CPB reproduced the intestinal damage of wild-type CN3685 and that damage was prevented by pre-incubating purified CPB with a CPB monoclonal antibody. These results indicate that CPB is both required and sufficient for CN3685-induced enteric pathology, supporting a key role for this toxin in type C intestinal pathogenesis.

157 citations


Cites background or methods or result from "Dissecting the contributions of Clo..."

  • ...perfringens type C human and veterinary infections, particularly as recent studies established that type C isolates typically express several potent toxins (Fisher et al., 2006)....

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  • ...all type C isolates during late log-phase vegetative growth (Fisher et al., 2006)....

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  • ...We have shown previously that CPB is the major contributor to lethality induced by intravenous injection of sterile type C isolate supernatants into mice (Fisher et al., 2006)....

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  • ...Those toxin production levels place CN3685 among the strongest 25% of PLC producers, strongest 10% of PFO producers and strongest 20% of CPB producers of the 45 type C disease isolates surveyed in that previous study (Fisher et al., 2006)....

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  • ...The separated proteins were transferred onto nitrocellulose membrane and Western blotted for detection of CPB using mouse monoclonal anti-CPB antibody, as described previously (Fisher et al., 2006)....

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References
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Book
01 Jan 1989
TL;DR: In this article, the authors discuss the causes of the following diseases: Diseases of the Alimentary Tract I. Diseases Caused by Toxins in Plants, Fungi, Cyanobacteria, Clavibacteria, Insects and Animals.
Abstract: Part 1. General Medicine: Clinical Examination and Making a Diagnosis. General Systemic States. Diseases of the Newborn. Practical Antimicrobial Therapeutics. Diseases of the Alimentary Tract I. Diseases of the Alimentary Tract II. Diseases of the Liver and Pancreas. Diseases of the Cardiovascular System. Diseases of the Blood and Blood-Forming Organs. Diseases of the Respiratory System. Diseases of the Urinary System. Diseases of the Nervous System. Diseases of the Musculoskeletal System. Diseases of the Skin, Conjunctiva and External Ear. Part 2. Special Medicine: Mastitis. Diseases Caused By Bacteria V. Diseases Caused By Viruses and Chlamydia I. Diseases Caused By Viruses and Chlamydia II. Diseases Caused By Rickettsia. Diseases Caused By Algae and Fungi. Diseases Caused By Protozoa. Diseases Caused By Helminth Parasites. Diseases Caused By Arthropod Parasites. Metabolic Diseases. Diseases Caused By Nutritional Deficiencies. Diseases Caused By Physical Agents. Diseases Caused By Inorganic and Farm Chemicals. Diseases Caused By Toxins in Plants, Fungi, Cyanobacteria, Clavibacteria, Insects and Animals. Diseases Caused By Allergy. Diseases Caused By the Inheritance of Undesirable Characters. Specific Diseases of Uncertain Etiology. Conversion Tables. Reference Laboratory Values. Index.

3,091 citations

Journal ArticleDOI
J G Songer1
TL;DR: This paper presents a meta-analyses of the prophylaxis and therapy practices followed by a discussion of these practices in relation to the case of C. perfringens.
Abstract: INTRODUCTION 216 CLOSTRIDIUM PERFRINGENS 216 Introduction 216 Major Toxins 216 Disease and Pathogenesis by Toxin Type 217 Type A 218 Type B 219 Type C 219 Type D 220 Type E 220 Enterotoxigenic C. perfringens 221 Reports of untyped C. perfringens 221 Prophylaxis and Therapy 222 Diagnosis 222 CLOSTRIDIUM SEPTICUM 223 Introduction 223 Virulence Attributes and Pathogenesis of Enteric Disease 223 Prophylaxis and Therapy 224 Diagnosis 224 CLOSTRIDIUM DIFFICILE 224 CLOSTRIDIUM SPIROFORME 225 CLOSTRIDIUM COLINUM 226 REFERENCES 226

906 citations


"Dissecting the contributions of Clo..." refers background or result in this paper

  • ...perfringens toxin, which has a mouse 50% lethal dose [LD50] of 310 ng/kg [27]) is responsible for the deaths resulting from type C infections (34)....

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  • ...alone does not cause classic type C disease (34)....

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  • ...Consistent with this possibility, animal model studies have shown that CPB alone cannot elicit the symptoms of a type C infection (34)....

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  • ...This model is believed to mimic the systemic phase of type C infections, in which type C toxins circulate systemically after absorption from the intestine (34)....

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  • ...Type C isolates cause several enteric diseases in domestic animals and have a significant impact on the agricultural industry, in terms of both livestock loss and vaccination costs (34)....

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Journal ArticleDOI
TL;DR: The genome analysis proved an efficient method for finding four members of the two-component VirR/VirS regulon that coordinately regulates the pathogenicity of C. perfringens, and a total of five hyaluronidase genes that will also contribute to virulence.
Abstract: Clostridium perfringens is a Gram-positive anaerobic spore-forming bacterium that causes life-threatening gas gangrene and mild enterotoxaemia in humans, although it colonizes as normal intestinal flora of humans and animals. The organism is known to produce a variety of toxins and enzymes that are responsible for the severe myonecrotic lesions. Here we report the complete 3,031,430-bp sequence of C. perfringens strain 13 that comprises 2,660 protein coding regions and 10 rRNA genes, showing pronounced low overall G + C content (28.6%). The genome contains typical anaerobic fermentation enzymes leading to gas production but no enzymes for the tricarboxylic acid cycle or respiratory chain. Various saccharolytic enzymes were found, but many enzymes for amino acid biosynthesis were lacking in the genome. Twenty genes were newly identified as putative virulence factors of C. perfringens, and we found a total of five hyaluronidase genes that will also contribute to virulence. The genome analysis also proved an efficient method for finding four members of the two-component VirR/VirS regulon that coordinately regulates the pathogenicity of C. perfringens. Clearly, C. perfringens obtains various essential materials from the host by producing several degradative enzymes and toxins, resulting in massive destruction of the host tissues.

699 citations

Journal ArticleDOI
TL;DR: Clostridium perfringens causes human gas gangrene and food poisoning as well as several enterotoxemic diseases of animals and is characterized by its ability to produce numerous extracellular toxins.
Abstract: ▪ Abstract Clostridium perfringens causes human gas gangrene and food poisoning as well as several enterotoxemic diseases of animals. The organism is characterized by its ability to produce numerous extracellular toxins including α-toxin or phospholipase C, θ-toxin or perfringolysin O, κ-toxin or collagenase, as well as a sporulation-associated enterotoxin. Although the genes encoding the α-toxin and θ-toxin are located on the chromosome, the genes encoding many of the other extracellular toxins are located on large plasmids. The enterotoxin gene can be either chromosomal or plasmid determined. Several of these toxin genes are associated with insertion sequences. The production of many of the extracellular toxins is regulated at the transcriptional level by the products of the virR and virS genes, which together comprise a two-component signal transduction system.

359 citations