Jason Brunt

University of Cambridge | Cam · Department of Chemical Engineering and Biotechnology

Clostridium botulinum is a dangerous pathogen that forms the highly potent botulinum toxin, which when ingested causes a deadly neuroparalytic disease. The closely related Clostridium sporogenes is occasionally pathogenic, frequently associated with food spoilage and regarded as the non-toxigenic equivalent of Group I C. botulinum. Both species for...

Clostridium sporogenes forms highly heat resistant endospores, enabling this bacterium to survive adverse conditions. Subsequently, spores may germinate, giving rise to vegetative cells that multiply and lead to food spoilage. Electron microscopy was used to visualise changes in spore structures during germination, emergence and outgrowth. C. sporo...

The deadly neurotoxins of Clostridium botulinum (BoNTs) comprise eight serotypes (A-G; X). The neurotoxin gene cluster encoding BoNT and its accessory proteins includes an operon containing an ntnh gene upstream of the boNT gene. Another operon contains either ha (haemagglutinin) or orfX genes (of unknown function). Here we describe a novel boNT ge...

Sialic acid (N-acetylneuraminic acid (Neu5Ac)) is commonly found in the terminal location of colonic mucin glycans where it is a much-coveted nutrient for gut bacteria, including Ruminococcus gnavus. R. gnavus is part of the healthy gut microbiota in humans, but it is disproportionately represented in diseases. There is therefore a need to understa...

Clostridium botulinum is an anaerobic spore forming bacterium that produces the potent botulinum neurotoxin that causes a severe and fatal neuro-paralytic disease of humans and animals (botulism). C. botulinum Group II is a psychrotrophic saccharolytic bacterium that forms spores of moderate heat resistance and is a particular hazard in minimally h...

Group I Clostridium botulinum and Clostridium sporogenes are physiologically and genetically closely related. Both are widely distributed in the environment and can cause foodborne botulism. In this work, a physiological study was conducted with 37 isolates from spoiled canned food and five referenced strains of C. sporogenes (three isolates) and G...

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 sprea...

Spores, the infectious agents of many Firmicutes, are remarkably resilient cell forms. Even distant relatives can have similar spore architectures although some display unique features; they all incorporate protective proteinaceous envelopes. We previously found that Bacillus spores can achieve these protective properties through extensive disulfid...

The neurotoxin formed by Clostridium botulinum Group II is a major cause of foodborne botulism, a deadly intoxication. This study aims to understand the genetic diversity and spread of C. botulinum Group II strains and their neurotoxin genes. A comparative genomic study has been conducted with 208 highly diverse C. botulinum Group II strains (180 n...

Spores, the infectious agents of many Firmicutes, are remarkably resilient cell forms. Even distant relatives have similar spore architectures incorporating protective proteinaceous envelopes. We reveal in nanometer detail how the outer envelope (exosporium) in Clostridium sporogenes (surrogate for C. botulinum group I), and in other Clostridial re...

Spore germination in Clostridium botulinum is the key step in the transformation of dormant, highly heat resistant spores into exponentially dividing vegetative cells that are capable of forming the deadly botulinum neurotoxin in food products. Our aim is to characterise the spore germination pathway in strains of C. botulinum Groups I and II by te...

Spore germination is a significant step in the transformation of dormant spores into exponentially dividing vegetative cells, and in the case of Clostridium botulinum in the formation of the deadly botulinum neurotoxin. Ingestion of approximately 30-100ng of preformed neurotoxin in food can be fatal, making the botulinum neurotoxin one of the most...

The Gram-positive spore-forming anaerobe Clostridium sporogenes is a significant cause of food spoilage, and it is also used as a surrogate for Clostridium botulinum spores for testing the efficacy of commercial sterilization. C. sporogenes spores have also been proposed as a vector to deliver drugs to tumor cells for cancer treatments. Such an app...

Spore germination is a significant step in the transformation of dormant spores into exponentially dividing vegetative cells, and in the case of Clostridium botulinum also the formation of the deadly botulinum neurotoxin. Our aim is to characterise the spore germination pathway in strains of C. botulinum Groups I and II by testing the effect of inp...

Foodborne botulism is a major health concern, causing fatality in approximately 10% of cases. Clostridium botulinum produces the neurotoxin, botulinum (BoNT), which is the most potent toxin known and ingesting 30-100ng of the toxin can be fatal. Spores of C. botulinum are extremely heat resistant and therefore, mild processing conditions of chilled...

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 i...

Genome mining is a powerful new technique for identifying genes with specific functions. Dr Jason Brunt and Professor Mike Peck from the Institute of Food Research describe their work to identify genes that control spore germination in the bacterium Clostridium botulinum, which causes botulism.

Foodborne botulism is a neuroparalytic disease caused by the ingestion of botulinum neurotoxin formed by strains of Group I Clostridium botulinum and Group II C. botulinum during their growth in food. Clostridium sporogenes is often involved in food spoilage and is widely regarded as the non-toxigenic equivalent of Group I C. botulinum. The formati...

Foodborne botulism is a neuroparalytic disease caused by the ingestion of botulinum neurotoxin formed by strains of proteolytic Clostridium botulinum and non-proteolytic C. botulinum during their growth in food. Clostridium sporogenes is usually involved in food spoilage and is often regarded as the non-toxigenic equivalent of proteolytic C. botuli...

To determine germination triggers of Clostridium frigidicarnis, an important spoilage bacterium of chilled vacuum-packed meat.  Germination of Cl. frigidicarnis spores in the presence of a range of potential nutrient and non-nutrient germinants was tested by monitoring the fall in optical density and by phase-contrast microscopy. The amino acid L-v...

Existing methods for detection of food-borne pathogens and their toxins are frequently time-consuming, require specialized equipment, and involve lengthy culture procedures and/or animal testing and are thus unsuitable for a rapid response to an emergency public health situation. A series of simple and rapid affinity immunochromatography column (AI...

Summary: The use of probiotics in aquaculture is steadily gaining momentum, supplementing or replacing the use of antimicrobial compounds in disease control. Probiotic organisms colonize the digestive tracts of their hosts and outcompete potential disease- causing organisms. There is accumulating evidence that probiotics inhibit a wide range of...

Probiotic bacterium GC2 (Aeromonas sobria) was shown to have beneficial effects in reducing infection with both the protozoan whitespot (Ichthyophtheirius multifiliis) and fish lice (Argulus foliaceus) in rainbow trout.

Bacterial subcellular components and probiotics were successful for the stimulation of immunity and the prevention of Vibrio harveyi infections in rainbow trout, Oncorhynchus mykiss (Walbaum). Rainbow trout were immunized with whole inactivated cells of V. harveyi to obtain polyclonal antibodies against specific antigens. Western blotting showed a...

Probiotics - the latest buzz word in fish farming? Such bacterial cultures have an important role in aquaculture for controlling serious bacterial disease and may provide a viable alternative to conventional treatments.

The aim of this study was to assess the efficacy of in-feed probiotics as a preventive measure against skin infections caused by Aeromonas bestiarum and Ichthyophthirius multifiliis (Ich) in rainbow trout. Fin rot was induced in fish by intradermal injection with 0.1 ml volumes containing 10(5) cells per ml A. bestiarum at the base of the dorsal fi...

The response of rainbow trout (Oncorhynchus mykiss, Walbaum) towards probiotics present in the feed was investigated by examining the proteome of serum as a measure of the acute phase response (APR). Proteomic analysis by two-dimensional electrophoresis (2D) concurrently with mass spectrometry was used to detect APR related proteins in rainbow trou...

To develop a probiotic with effectiveness against Aeromonas sp., which was pathogenic to rainbow trout. When Bacillus subtilis AB1, which was obtained from fish intestine, was administered for 14 days to rainbow trout in feed at a concentration of 10(7) cells per gram either as viable, formalized or sonicated cells or as cell-free supernatant, the...

JB-1 and GC2, which were equated with Bacillus sp. and Aeromonas sobria respectively, were recovered from the digestive tract of rainbow trout, Oncorhynchus mykiss and ghost carp, Cyprinus sp. respectively, and demonstrated effectiveness as probiotics for the control of infections caused by Aeromonas salmonicida, Lactococcus garvieae, Streptococcus...

The aim of this study was to understand the microbial community of intestinal contents and mucosal layer in the intestine of rainbow trout by means of culture-dependent conventional and independent molecular techniques. Forty-one culturable microbial phylotypes, and 39 sequences from 16S rRNA and two from 18S rRNA genes, were retrieved. Aeromonadac...

From a comparison of 125 bacterial isolates recovered from the digestive tract of rainbow trout, Oncorhynchus mykiss, and carp, Cyprinus sp., a culture was obtained which was effective at preventing clinical disease caused by Lactococcus garvieae and Streptococcus iniae when used as a feed additive. The culture, Aeromonas sobria GC2, was incorporat...