botulinum and Clostridium laboratories and actively consult the food industry in questions related to food safety risk assessment and risk management.
Ongoing and previous projects:
whyBOTher: Why does Clostridium botulinum kill? – In search for botulinum neurotoxin regulators
Bacterial toxins cause devastating diseases in humans and animals, ranging from necrotic enteritis to gas gangrene and tetraplegia. While toxin synthesis probably endows these bacteria with a selective advantage in their natural habitats, toxigenesis is likely to represent a fitness cost. It is thus plausible that mild environments encourage bacteria to give up toxin production, or reduce the number of toxigenic cells in populations. The cellular strategies bacteria use to silence toxin production and to establish stably non-toxigenic subpopulations represent targets for innovative antitoxin and vaccine strategies that can be utilized by the food, feed, medical, and agricultural sectors. I have found the first repressor that blocks the production of the most poisonous substance known to mankind, botulinum neurotoxin (BOT). This toxin, also known as “botox”, kills in nanogram quantities and is produced by the notorious food pathogen, Clostridium botulinum. In whyBOTher, we will extend the knowledge from this single regulator to comprehensive understanding of how C. botulinum cultures coordinate BOT production between single cells and cell subpopulations in response to their physical and social environment, and which genetic and plastic cellular strategies the cells take to attenuate BOT production in short and long term. We will experimentally force evolution of BOT-producing and non-producing cell lines, and explore the genetic, epigenetic, and cellular factors that explain the emergence of the two cell lines. To achieve this goal, I will extend the research on C. botulinum biology in two dimensions: from population level to fluorescent single-cell biology, and from genomic information to functional analysis of regulatory and metabolic networks controlling BOT production. whyBOTher represents an unprecedented research effort into regulation of bacterial toxins, and introduces a shift in paradigm from population-level observations to the life of single bacterial cells.
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Academy Research Project: The decadent life of Clostridium botulinum: Neurotoxins and escape in endospores
Botulinum neurotoxin (BOT) is the most poisonous substance that causes a life-threatening paralysis, botulism. BOT is produced by growing cultures of the ubiquitous bacterium Clostridium botulinum. Botulism may follow ingestion of BOT with food, feed, or drink, or arise from C. botulinum infection in vivo. Apart from BOT production, exhausting C. botulinum cultures produce highly tolerant endospores that survive in harsh conditions for decades. It is not understood how the cultures coordinate BOT production and sporulation between cells and cell subpopulations. Understanding the link between the two traits and related regulation would open up novel approaches to control the food safety and public health risks caused by BOT production. The project exploits novel state-of-the-art cell biology and genetics tools to unravel the cellular coordination of BOT production and sporulation, enabling a fundamentally novel level of understanding the two traits.
ANIBOTNET: Animal botulism, innovative tools for diagnosis, prevention, control and epidemiological investigation
Animal botulism is a re-emerging problem worldwide that concerns several species (cattle, mink, horses and birds) and both livestock production and wildlife. This leads to huge economical losses in the animal industry because of high mortality rates. It also presents a risk for transmission to other species, including humans. Despite being reported for a long time, many aspects of the disease have been neglected up to now, in particular approaches for diagnosis and surveillance of botulism have to be improved and harmonized and control and prevention measures have to be developed. This project aims first at developing an alternative approach to the mouse bioassay, which today is still the gold standard for botulism diagnosis because of the lack of validated in vitro assay. An animal replacement method based on mass spectrometry (Endopep-MS) will be improved and standardized to lead to a sensitive and rapid test for laboratory diagnosis. This project will also explore the epidemiological aspects of animal botulism focusing on potential risk factors associated with the outbreaks for better managing animal botulism surveillance systems. As a useful tool intended for molecular epidemiology and for the assessment of genetic diversity of Clostridium botulinum group III organisms, Multiple Locus of Variable tandem repeat Analysis and Multilocus Sequence Typing protocols will be developed and whole genome sequencing will be performed. In addition, the sequence variability of botulinum neurotoxins will be determined using mass spectrometry. Usefulness of this approach for epidemiological applications will be evaluated. Finally, we will focus on the development of prevention and control strategies by testing three strategies: vaccination, use of lactic acid bacteria as antagonist of C. botulinum group III organism growth and toxinogenesis and set up consolidated guidelines for sampling and laboratory testing in botulism outbreaks.
This collaborative 36-month project involves 8 research groups from EU with complementary expertise in C. botulinum, botulinum neurotoxins, mass spectrometry, veterinary diagnostics, genomic studies, epidemiology, and animal experiments. This project will allow a prompt diagnosis of animal botulism, will make available molecular tools which are essential to react early in case of major outbreaks, will clarify essential epidemiological aspects of botulism in poultry and bovine production in Europe, and finally will propose countermeasures.
For more information, please visit: http://www.anihwa-submission-era.net/home.html
CLOSPORE: Research network funded by the European Commission through its Marie Skłodowska-Curie Actions programme
The bacterial endospore is one of the most highly resistant life-forms on earth and allows the bacterium to survive exposure to extremes of temperature, desiccation, radiation, disinfectants and, in the case of Clostridium, oxygen. The longevity of survival is astounding and can be measured not in tens or hundreds of years but, in millions. These remarkable structures are the most important single feature of the genus Clostridium. Thus, whilst the pathogenesis of its notorious pathogens (C. botulinum, C. perfringens and C. difficile) is ascribed to the devastating toxins produced (neurotoxins, endotoxins and cytotoxins), it is their capacity to produce spores that lies at the heart of the diseases they cause. This is because spores play the pivotal role in the spread of infection (e.g., C. difficile) and in foodstuff contamination and food poisoning (eg, C. botulinum and C. perfringens). The processes of spore formation (sporulation) and germination (return of the dormant spore to toxin-producing, vegetative cells), therefore, represent key intervention points.
On the other hand, the majority of clostridia are entirely benign and can sustainably produce all manner of useful chemicals and fuels. Crucially, the regulation of chemical production is intimately linked to that of sporulation. Spores of benign species may also be used as a delivery system for treating cancer. This is because intravenously injected spores localise to and selectively germinate in the hypoxic centres of solid tumours, a property that can be used to deliver anti-tumour agents. Moreover, the phage-mediated delivery of small, acid-soluble protein (SASP) derived from spores are the basis of an innovative approach to the killing of antibiotic resistant bacteria. Yet, despite the tremendous importance of the spore, little is known of the developmental processes of clostridial sporulation and germination. Deriving this knowledge, and thence exploiting it, is the objective of CLOSPORE.
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