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Mycobacterium avium subspecies paratuberculosis (MAP) are detectable viable in milk and other dairy products. The molecular mechanisms allowing the adaptation of MAP in these products are still poorly understood. To obtain information about respective adaptation of MAP in milk, we differentially analyzed the proteomes of MAP cultivated for 48 h in either milk at 37 °C or 4 °C or Middlebrook 7H9 broth as a control. From a total of 2197 MAP proteins identified, 242 proteins were at least fivefold higher in abundance in milk. MAP responded to the nutritional shortage in milk with upregulation of 32% of proteins with function in metabolism and 17% in fatty acid metabolism/synthesis. Additionally, MAP upregulated clusters of 19% proteins with roles in stress responses and immune evasion, 19% in transcription/translation, and 13% in bacterial cell wall synthesis. Dut, MmpL4_1, and RecA were only detected in MAP incubated in milk, pointing to very important roles of these proteins for MAP coping with a stressful environment. Dut is essential and plays an exclusive role for growth, MmpL4_1 for virulence through secretion of specific lipids, and RecA for SOS response of mycobacteria. Further, 35 candidates with stable expression in all conditions were detected, which could serve as targets for detection. Data are available via ProteomeXchange with identifier PXD027444.
Kristina J. H. Kleinwort; Bernhard F. Hobmaier; Ricarda Mayer; Christina Hölzel; Roxane L. Degroote; Erwin Märtlbauer; Stefanie M. Hauck; Cornelia A. Deeg. Mycobacterium avium subsp. paratuberculosis Proteome Changes Profoundly in Milk. Metabolites 2021, 11, 549 .
AMA StyleKristina J. H. Kleinwort, Bernhard F. Hobmaier, Ricarda Mayer, Christina Hölzel, Roxane L. Degroote, Erwin Märtlbauer, Stefanie M. Hauck, Cornelia A. Deeg. Mycobacterium avium subsp. paratuberculosis Proteome Changes Profoundly in Milk. Metabolites. 2021; 11 (8):549.
Chicago/Turabian StyleKristina J. H. Kleinwort; Bernhard F. Hobmaier; Ricarda Mayer; Christina Hölzel; Roxane L. Degroote; Erwin Märtlbauer; Stefanie M. Hauck; Cornelia A. Deeg. 2021. "Mycobacterium avium subsp. paratuberculosis Proteome Changes Profoundly in Milk." Metabolites 11, no. 8: 549.
Bacillus cereus sensu stricto is an important pathogen causing food poisoning, as well as extraintestinal diseases
Erwin Märtlbauer; Per Granum. Bacillus cereus Toxins. Toxins 2021, 13, 295 .
AMA StyleErwin Märtlbauer, Per Granum. Bacillus cereus Toxins. Toxins. 2021; 13 (5):295.
Chicago/Turabian StyleErwin Märtlbauer; Per Granum. 2021. "Bacillus cereus Toxins." Toxins 13, no. 5: 295.
Bacillus cereus is a ubiquitous soil bacterium responsible for two types of food-associated gastrointestinal diseases. While the emetic type, a food intoxication, manifests in nausea and vomiting, food infections with enteropathogenic strains cause diarrhea and abdominal pain. Causative toxins are the cyclic dodecadepsipeptide cereulide, and the proteinaceous enterotoxins hemolysin BL (Hbl), nonhemolytic enterotoxin (Nhe) and cytotoxin K (CytK), respectively. This review covers the current knowledge on distribution and genetic organization of the toxin genes, as well as mechanisms of enterotoxin gene regulation and toxin secretion. In this context, the exceptionally high variability of toxin production between single strains is highlighted. In addition, the mode of action of the pore-forming enterotoxins and their effect on target cells is described in detail. The main focus of this review are the two tripartite enterotoxin complexes Hbl and Nhe, but the latest findings on cereulide and CytK are also presented, as well as methods for toxin detection, and the contribution of further putative virulence factors to the diarrheal disease.
Richard Dietrich; Nadja Jessberger; Monika Ehling-Schulz; Erwin Märtlbauer; Per Granum. The Food Poisoning Toxins of Bacillus cereus. Toxins 2021, 13, 98 .
AMA StyleRichard Dietrich, Nadja Jessberger, Monika Ehling-Schulz, Erwin Märtlbauer, Per Granum. The Food Poisoning Toxins of Bacillus cereus. Toxins. 2021; 13 (2):98.
Chicago/Turabian StyleRichard Dietrich; Nadja Jessberger; Monika Ehling-Schulz; Erwin Märtlbauer; Per Granum. 2021. "The Food Poisoning Toxins of Bacillus cereus." Toxins 13, no. 2: 98.
The ubiquitous soil bacterium Bacillus cereus presents major challenges to food safety. It is responsible for two types of food poisoning, the emetic form due to food intoxication and the diarrheal form emerging from food infections with enteropathogenic strains, also known as toxico-infections, which are the subject of this review. The diarrheal type of food poisoning emerges after production of enterotoxins by viable bacteria in the human intestine. Basically, the manifestation of the disease is, however, the result of a multifactorial process, including B. cereus prevalence and survival in different foods, survival of the stomach passage, spore germination, motility, adhesion, and finally enterotoxin production in the intestine. Moreover, all of these processes are influenced by the consumed foodstuffs as well as the intestinal microbiota which have, therefore, to be considered for a reliable prediction of the hazardous potential of contaminated foods. Current knowledge regarding these single aspects is summarized in this review aiming for risk-oriented diagnostics for enteropathogenic B. cereus.
Nadja Jessberger; Richard Dietrich; Per Granum; Erwin Märtlbauer. The Bacillus cereus Food Infection as Multifactorial Process. Toxins 2020, 12, 701 .
AMA StyleNadja Jessberger, Richard Dietrich, Per Granum, Erwin Märtlbauer. The Bacillus cereus Food Infection as Multifactorial Process. Toxins. 2020; 12 (11):701.
Chicago/Turabian StyleNadja Jessberger; Richard Dietrich; Per Granum; Erwin Märtlbauer. 2020. "The Bacillus cereus Food Infection as Multifactorial Process." Toxins 12, no. 11: 701.
Bacillus cereus Hemolysin BL is a tripartite toxin responsible for a diarrheal type of food poisoning. Open questions remain regarding its mode of action, including the extent to which complex formation prior to cell binding contributes to pore-forming activity, how these complexes are composed, and the properties of the pores formed in the target cell membrane. Distinct complexes of up to 600 kDa were found on native gels, whose structure and size were primarily defined by Hbl B. Hbl L1 and L2 were also identified in these complexes using Western blotting and an LC-MS approach. LC-MS also revealed that many other proteins secreted by B. cereus exist in complexes. Further, a decrease of toxic activity at temperatures ≥60 °C was shown, which was unexpectedly restored at higher temperatures. This could be attributed to a release of Hbl B monomers from tight complexation, resulting in enhanced cell binding. In contrast, Hbl L1 was rather susceptible to heat, while heat treatment of Hbl L2 seemed not to be crucial. Furthermore, Hbl-induced pores had a rather small single-channel conductance of around 200 pS and a probable channel diameter of at least 1 nm on planar lipid bilayers. These were highly instable and had a limited lifetime, and were also slightly cation-selective. Altogether, this study provides astonishing new insights into the complex mechanism of Hbl pore formation, as well as the properties of the pores.
Nadja Jessberger; Richard Dietrich; Kristina Schauer; Stefanie Schwemmer; Erwin Märtlbauer; Roland Benz. Characteristics of the Protein Complexes and Pores Formed by Bacillus cereus Hemolysin BL. Toxins 2020, 12, 672 .
AMA StyleNadja Jessberger, Richard Dietrich, Kristina Schauer, Stefanie Schwemmer, Erwin Märtlbauer, Roland Benz. Characteristics of the Protein Complexes and Pores Formed by Bacillus cereus Hemolysin BL. Toxins. 2020; 12 (11):672.
Chicago/Turabian StyleNadja Jessberger; Richard Dietrich; Kristina Schauer; Stefanie Schwemmer; Erwin Märtlbauer; Roland Benz. 2020. "Characteristics of the Protein Complexes and Pores Formed by Bacillus cereus Hemolysin BL." Toxins 12, no. 11: 672.
Despite its benefits as biological insecticide, Bacillus thuringiensis bears enterotoxins, which can be responsible for a diarrhoeal type of food poisoning. Thus, all 24 isolates from foodstuffs, animals, soil and commercially used biopesticides tested in this study showed the genetic prerequisites necessary to provoke the disease. Moreover, though highly strain-specific, various isolates were able to germinate and also to actively move, which are further requirements for the onset of the disease. Most importantly, all isolates could grow under simulated intestinal conditions and produce significant amounts of enterotoxins. Cytotoxicity assays classified 14 isolates as highly, eight as medium and only two as low toxic. Additionally, growth inhibition by essential oils (EOs) was investigated as preventive measure against putatively enteropathogenic B. thuringiensis. Cinnamon Chinese cassia showed the highest antimicrobial activity, followed by citral, oregano and winter savory. In all tests, high strain-specific variations appeared and must be taken into account when evaluating the hazardous potential of B. thuringiensis and using EOs as antimicrobials. Altogether, the present study shows a non-negligible pathogenic potential of B. thuringiensis, independently from the origin of isolation. Generally, biopesticide strains were indistinguishable from other isolates. Thus, the use of these pesticides might indeed increase the risk for consumers’ health. Until complete information about the safety of the applied strains and formulations is available, consumers or manufacturers might benefit from the antimicrobial activity of EOs to reduce the level of contamination.
Valerie Schwenk; Janina Riegg; Monique Lacroix; Erwin Märtlbauer; Nadja Jessberger. Enteropathogenic Potential of Bacillus thuringiensis Isolates from Soil, Animals, Food and Biopesticides. Foods 2020, 9, 1484 .
AMA StyleValerie Schwenk, Janina Riegg, Monique Lacroix, Erwin Märtlbauer, Nadja Jessberger. Enteropathogenic Potential of Bacillus thuringiensis Isolates from Soil, Animals, Food and Biopesticides. Foods. 2020; 9 (10):1484.
Chicago/Turabian StyleValerie Schwenk; Janina Riegg; Monique Lacroix; Erwin Märtlbauer; Nadja Jessberger. 2020. "Enteropathogenic Potential of Bacillus thuringiensis Isolates from Soil, Animals, Food and Biopesticides." Foods 9, no. 10: 1484.
Inflammasomes are important for host defence against pathogens and homeostasis with commensal microbes. Here, we show non-haemolytic enterotoxin (NHE) from the neglected human foodborne pathogen Bacillus cereus is an activator of the NLRP3 inflammasome and pyroptosis. NHE is a non-redundant toxin to haemolysin BL (HBL) despite having a similar mechanism of action. Via a putative transmembrane region, subunit C of NHE initiates binding to the plasma membrane, leading to the recruitment of subunit B and subunit A, thus forming a tripartite lytic pore that is permissive to efflux of potassium. NHE mediates killing of cells from multiple lineages and hosts, highlighting a versatile functional repertoire in different host species. These data indicate that NHE and HBL operate synergistically to induce inflammation and show that multiple virulence factors from the same pathogen with conserved function and mechanism of action can be exploited for sensing by a single inflammasome.
Daniel Fox; Anukriti Mathur; Yansong Xue; Yunqi Liu; Wei Hong Tan; Shouya Feng; Abhimanu Pandey; Chinh Ngo; Jenni Hayward; Ines I. Atmosukarto; Jason D. Price; Matthew D. Johnson; Nadja Jessberger; Avril A. B. Robertson; Gaetan Burgio; David C. Tscharke; Edward M. Fox; Denisse Leyton; Nadeem O. Kaakoush; Erwin Märtlbauer; Stephen H. Leppla; Si Ming Man. Bacillus cereus non-haemolytic enterotoxin activates the NLRP3 inflammasome. Nature Communications 2020, 11, 1 -16.
AMA StyleDaniel Fox, Anukriti Mathur, Yansong Xue, Yunqi Liu, Wei Hong Tan, Shouya Feng, Abhimanu Pandey, Chinh Ngo, Jenni Hayward, Ines I. Atmosukarto, Jason D. Price, Matthew D. Johnson, Nadja Jessberger, Avril A. B. Robertson, Gaetan Burgio, David C. Tscharke, Edward M. Fox, Denisse Leyton, Nadeem O. Kaakoush, Erwin Märtlbauer, Stephen H. Leppla, Si Ming Man. Bacillus cereus non-haemolytic enterotoxin activates the NLRP3 inflammasome. Nature Communications. 2020; 11 (1):1-16.
Chicago/Turabian StyleDaniel Fox; Anukriti Mathur; Yansong Xue; Yunqi Liu; Wei Hong Tan; Shouya Feng; Abhimanu Pandey; Chinh Ngo; Jenni Hayward; Ines I. Atmosukarto; Jason D. Price; Matthew D. Johnson; Nadja Jessberger; Avril A. B. Robertson; Gaetan Burgio; David C. Tscharke; Edward M. Fox; Denisse Leyton; Nadeem O. Kaakoush; Erwin Märtlbauer; Stephen H. Leppla; Si Ming Man. 2020. "Bacillus cereus non-haemolytic enterotoxin activates the NLRP3 inflammasome." Nature Communications 11, no. 1: 1-16.
Modern threats of bioterrorism force the need for multiple detection of biothreat agents to determine the presence or absence of such agents in suspicious samples. Here, we present a rapid electrochemical fiveplex biochip screening assay for detection of the bioterrorism relevant low molecular weight toxins saxitoxin, microcystin-LR, T-2 toxin, roridin A and aflatoxin B1 relying on anti-idiotypic antibodies as epitope-mimicking reagents. The proposed method avoids the use of potentially harmful toxin-protein conjugates usually mandatory for competitive immunoassays. The biochip is processed and analyzed on the automated and portable detection platform pBDi within 13.4 min. The fiveplex biochip assay revealed toxin group specificity to multiple congeners. Limits of detection were 1.2 ng/mL, 1.5 ng/mL, 0.4 ng/mL, 0.5 ng/mL and 0.6 ng/mL for saxitoxin, microcystin-LR, T-2 toxin, roridin A or aflatoxin B1, respectively. The robustness of the fiveplex biochip for real samples was demonstrated by detecting saxitoxin, microcystin-LR, HT-2 toxin, roridin A and aflatoxin B1 in contaminated human blood serum without elaborate sample preparation. Recovery rates were between 52–115% covering a wide concentration range. Thus, the developed robust fiveplex biochip assay can be used on-site to quickly detect one or multiple low molecular weight toxins in a single run.
Katharina Schulz; Christopher Pöhlmann; Richard Dietrich; Erwin Märtlbauer; Thomas Elßner. An Electrochemical Fiveplex Biochip Assay Based on Anti-Idiotypic Antibodies for Fast On-Site Detection of Bioterrorism Relevant Low Molecular Weight Toxins. Toxins 2019, 11, 696 .
AMA StyleKatharina Schulz, Christopher Pöhlmann, Richard Dietrich, Erwin Märtlbauer, Thomas Elßner. An Electrochemical Fiveplex Biochip Assay Based on Anti-Idiotypic Antibodies for Fast On-Site Detection of Bioterrorism Relevant Low Molecular Weight Toxins. Toxins. 2019; 11 (12):696.
Chicago/Turabian StyleKatharina Schulz; Christopher Pöhlmann; Richard Dietrich; Erwin Märtlbauer; Thomas Elßner. 2019. "An Electrochemical Fiveplex Biochip Assay Based on Anti-Idiotypic Antibodies for Fast On-Site Detection of Bioterrorism Relevant Low Molecular Weight Toxins." Toxins 11, no. 12: 696.
Mycobacterium avium subsp. paratuberculosis (MAP) is a pathogen causing paratuberculosis in cattle and small ruminants. During the long asymptomatic subclinical stage, high numbers of MAP are excreted and can be transmitted to food for human consumption, where they survive many of the standard techniques of food decontamination. Whether MAP is a human pathogen is currently under debate. The aim of this study was a better understanding of the host-pathogen response by analyzing the interaction of peripheral blood lymphocytes (PBL) from cattle with MAP in their exoproteomes/secretomes to gain more information about the pathogenic mechanisms of MAP. Because in other mycobacterial infections, the immune phenotype correlates with susceptibility, we additionally tested the interaction of MAP with recently detected cattle with a different immune capacity referred as immune deviant (ID) cows. In PBL, different biological pathways were enhanced in response to MAP dependent on the immune phenotype of the host. PBL of control cows activated members of cell activation and chemotaxis of leukocytes pathway as well as IL-12 mediated signaling. In contrast, in ID cows CNOT1 was detected as highly abundant protein, pointing to a different immune response, which could be favorable for MAP. Additionally, MAP exoproteomes differed in either GroEL1 or DnaK abundance, depending on the interacting host immune response. These finding point to an interdependent, tightly regulated response of the bovine immune system to MAP and vise versa.
Kristina J.H. Kleinwort; Stefanie M. Hauck; Roxane Degroote; Armin M. Scholz; Christina Hölzel; Erwin P. Maertlbauer; Cornelia Deeg. Peripheral blood bovine lymphocytes and MAP show distinctly different proteome changes and immune pathways in host-pathogen interaction. PeerJ 2019, 7, e8130 .
AMA StyleKristina J.H. Kleinwort, Stefanie M. Hauck, Roxane Degroote, Armin M. Scholz, Christina Hölzel, Erwin P. Maertlbauer, Cornelia Deeg. Peripheral blood bovine lymphocytes and MAP show distinctly different proteome changes and immune pathways in host-pathogen interaction. PeerJ. 2019; 7 ():e8130.
Chicago/Turabian StyleKristina J.H. Kleinwort; Stefanie M. Hauck; Roxane Degroote; Armin M. Scholz; Christina Hölzel; Erwin P. Maertlbauer; Cornelia Deeg. 2019. "Peripheral blood bovine lymphocytes and MAP show distinctly different proteome changes and immune pathways in host-pathogen interaction." PeerJ 7, no. : e8130.
Worldwide infections by Shiga toxin-producing Escherichia coli (STEC) in humans have been reported after consumption of mainly beef, but also deer meat. Not only the consumption of contaminated deer meat represents a risk, but also the transmission of STEC between deer and domestic animals should be considered. Within the framework of a telemetry study of roe deer (Capreolus capreolus) the aim was to analyse the occurrence of STEC. Due to the chance to sample some animals several times it was possible to obtain data on the repeated shedding of STEC in roe deer. In total 124 faeces or rectal swabs of 77 live trapped roe deer were collected. The isolates obtained were characterized for stx subtypes, different virulence genes, the so-called top-five serogroups, phylogenetic groups, PFGE-types and antimicrobial susceptibilities. The majority of roe deer were stx-positive whenever sampled. Twenty-eight animals were sampled more than once and were used to examine the duration of shedding STEC. The time interval of 6 persistently stx-negative tested animals was between 6 and 440d (median 49d, interquartile range (IQR) 17-258d). Ten animals excreted undistinguishable STEC strains in intervals between 4 and 778d (median 42d, IQR 22-79d). Most of the isolates were stx2b-positive, eae-negative and frequently ehlyA-positive. None of the isolates belonged to serogroup O26, O103, O111, O145 and O157, respectively. All isolates were sensitive to the antimicrobial substances tested. Although the duration of each shedding event could not be determined the results indicate long-term excretion of STEC in roe deer. This is an important consideration for the observance of good hygiene practice while field dressing of deer and preparing deer meat.
E. Frank; R. Bonke; N. Drees; M. Heurich; Erwin Märtlbauer; M. Gareis. Shiga toxin-producing Escherichia coli (STEC) shedding in a wild roe deer population. Veterinary Microbiology 2019, 239, 108479 .
AMA StyleE. Frank, R. Bonke, N. Drees, M. Heurich, Erwin Märtlbauer, M. Gareis. Shiga toxin-producing Escherichia coli (STEC) shedding in a wild roe deer population. Veterinary Microbiology. 2019; 239 ():108479.
Chicago/Turabian StyleE. Frank; R. Bonke; N. Drees; M. Heurich; Erwin Märtlbauer; M. Gareis. 2019. "Shiga toxin-producing Escherichia coli (STEC) shedding in a wild roe deer population." Veterinary Microbiology 239, no. : 108479.
The diarrheal type of food poisoning caused by enteropathogenic Bacillus cereus has been linked to various exotoxins. Best described are the non-hemolytic enterotoxin (Nhe), hemolysin BL (Hbl), and cytotoxin K (CytK). Due to the ubiquitous prevalence of B. cereus in soil and crops and its ability to form highly resistant endospores, contaminations during food production and processing cannot be completely avoided. Although phylogenetically closely related, enteropathogenic B. cereus strains show a high versatility of their toxic potential. Thus, functional tools for evaluating the pathogenic potential are urgently needed in order to predict hazardous food contaminations. As the diarrheal syndrome is the result of a toxico-infection with enterotoxin production in the intestine, the entire passage of the bacteria within the host, from spore survival in the stomach, spore germination, host cell adherence, and motility, to enterotoxin production under simulated intestinal conditions was compared in a panel of 20 strains, including high pathogenic as well as apathogenic ones. This approach resulted in an overarching virulence analysis scheme. In parallel, we searched for potential toxico-specific secreted markers to discriminate low and high pathogenic strains. To this end, we targeted known exotoxins using an easy to implement immunoblotting approach as well as a caseinolytic exoprotease activity assay. Overall, Nhe component B, sphingomyelinase, and exoproteases showed good correlation with the complex virulence analysis scheme and can serve as a template for future fast and easy risk assessment tools to be implemented in routine diagnostic procedures and HACCP studies.
Nadja Jessberger; Markus Kranzler; Claudia Da Riol; Valerie Schwenk; Tanja Buchacher; Richard Dietrich; Monika Ehling-Schulz; Erwin Märtlbauer. Assessing the toxic potential of enteropathogenic Bacillus cereus. Food Microbiology 2019, 84, 103276 .
AMA StyleNadja Jessberger, Markus Kranzler, Claudia Da Riol, Valerie Schwenk, Tanja Buchacher, Richard Dietrich, Monika Ehling-Schulz, Erwin Märtlbauer. Assessing the toxic potential of enteropathogenic Bacillus cereus. Food Microbiology. 2019; 84 ():103276.
Chicago/Turabian StyleNadja Jessberger; Markus Kranzler; Claudia Da Riol; Valerie Schwenk; Tanja Buchacher; Richard Dietrich; Monika Ehling-Schulz; Erwin Märtlbauer. 2019. "Assessing the toxic potential of enteropathogenic Bacillus cereus." Food Microbiology 84, no. : 103276.
A major virulence factor involved in Bacillus cereus food poisoning is the three-component enterotoxin hemolysin BL. It consists of the binding component B and the two lytic components L1 and L2. Studying its mode of action has been challenging, as natural culture supernatants additionally contain Nhe, the second three-component enterotoxin, and purification of recombinant (r) Hbl components has been difficult. In this study, we report on pore-forming, cytotoxic, cell binding and hemolytic activity of recently generated rHbl components expressed in E. coli. It is known that all three Hbl components are necessary for cytotoxicity and pore formation. Here we show that an excess of rHbl B enhances, while an excess of rHbl L1 hinders, the velocity of pore formation. Most rapid pore formation was observed with ratios L2:L1:B = 1:1:10 and 10:1:10. It was further verified that Hbl activity is due to sequential binding of the components B - L1 - L2. Accordingly, all bioassays proved that binding of Hbl B to the cell surface is the crucial step for pore formation and cytotoxic activity. Binding of Hbl B took place within minutes, while apposition of the following L1 and L2 occurred immediately. Further on, applying toxin components simultaneously, it seemed that Hbl L1 enhanced binding of B to the target cell surface. Overall, these data contribute significantly to the elucidation of the mode of action of Hbl, and suggest that its mechanism of pore formation differs substantially from that of Nhe, although both enterotoxin complexes are sequentially highly related.
Nadja Jessberger; Richard Dietrich; Stefanie Schwemmer; Franziska Tausch; Valerie Schwenk; Andrea Didier; Erwin Märtlbauer. Binding to The Target Cell Surface Is The Crucial Step in Pore Formation of Hemolysin BL from Bacillus cereus. Toxins 2019, 11, 281 .
AMA StyleNadja Jessberger, Richard Dietrich, Stefanie Schwemmer, Franziska Tausch, Valerie Schwenk, Andrea Didier, Erwin Märtlbauer. Binding to The Target Cell Surface Is The Crucial Step in Pore Formation of Hemolysin BL from Bacillus cereus. Toxins. 2019; 11 (5):281.
Chicago/Turabian StyleNadja Jessberger; Richard Dietrich; Stefanie Schwemmer; Franziska Tausch; Valerie Schwenk; Andrea Didier; Erwin Märtlbauer. 2019. "Binding to The Target Cell Surface Is The Crucial Step in Pore Formation of Hemolysin BL from Bacillus cereus." Toxins 11, no. 5: 281.
Strains of the Bacillus cereus group have been widely used as probiotics for human beings, food animals, plants, and environmental remediation. Paradoxically, B. cereus is responsible for both gastrointestinal and nongastrointestinal syndromes and represents an important opportunistic food-borne pathogen. Toxicity assessment is a fundamental issue to evaluate safety of probiotics. Here, we summarize the state of our current knowledge about the toxins of B. cereus sensu lato to be considered for safety assessment of probiotic candidates. Surfactin-like emetic toxin (cereulide) and various enterotoxins including nonhemolytic enterotoxin, hemolysin BL, and cytotoxin K are responsible for food poisoning outbreaks characterized by emesis and diarrhea. In addition, other factors, such as hemolysin II, Certhrax, immune inhibitor A1, and sphingomyelinase, contribute to toxicity and overall virulence of B. cereus.
Yifang Cui; Erwin Märtlbauer; Richard Dietrich; Hailing Luo; Shuangyang Ding; Kui Zhu. Multifaceted toxin profile, an approach toward a better understanding of probioticBacillus cereus. Critical Reviews in Toxicology 2019, 49, 342 -356.
AMA StyleYifang Cui, Erwin Märtlbauer, Richard Dietrich, Hailing Luo, Shuangyang Ding, Kui Zhu. Multifaceted toxin profile, an approach toward a better understanding of probioticBacillus cereus. Critical Reviews in Toxicology. 2019; 49 (4):342-356.
Chicago/Turabian StyleYifang Cui; Erwin Märtlbauer; Richard Dietrich; Hailing Luo; Shuangyang Ding; Kui Zhu. 2019. "Multifaceted toxin profile, an approach toward a better understanding of probioticBacillus cereus." Critical Reviews in Toxicology 49, no. 4: 342-356.
Enteropathogenic Bacillus cereus causes foodborne infections due to the production of pore-forming enterotoxins in the intestine. Before that, spores have to be ingested, survive the stomach passage, and germinate.
Nadja Jessberger; Richard Dietrich; Ann-Katrin Mohr; Claudia Da Riol; Erwin Märtlbauer. Porcine Gastric Mucin Triggers Toxin Production of Enteropathogenic Bacillus cereus. Infection and Immunity 2019, 87, 1 .
AMA StyleNadja Jessberger, Richard Dietrich, Ann-Katrin Mohr, Claudia Da Riol, Erwin Märtlbauer. Porcine Gastric Mucin Triggers Toxin Production of Enteropathogenic Bacillus cereus. Infection and Immunity. 2019; 87 (4):1.
Chicago/Turabian StyleNadja Jessberger; Richard Dietrich; Ann-Katrin Mohr; Claudia Da Riol; Erwin Märtlbauer. 2019. "Porcine Gastric Mucin Triggers Toxin Production of Enteropathogenic Bacillus cereus." Infection and Immunity 87, no. 4: 1.
Mycobacterium avium subsp. paratuberculosis (MAP) is a pathogen causing paratuberculosis in cattle and small ruminants. During the long asymptomatic subclinical stage, high numbers of MAP are excreted and can be transmitted to food, where they survive many of the standard techniques of food decontamination. If these MAP are harmful to the consumers is currently under debate. In general, there is a lack of information regarding interaction of the hosts immune system with MAP.In this study, we tested the interaction of peripheral blood lymphocytes (PBL) from cattle with MAP in their exoproteomes/secretomes. Because in other mycobacterial infections, the immune phenotype correlates with susceptibility, we additionally tested the interaction of MAP with recently detected immune deviant cows.In PBL, different biological pathways were enhanced in response to MAP dependent on the immune phenotype of the host. PBL of control cows activated members of cell activation and chemotaxis of leukocytes pathway as well as IL-12 mediated signaling. In contrast, in ID cows CNOT1 was detected as highly abundant protein, pointing to a different immune response, which could be favorable for MAP. Additionally, MAP reacted different to the hosts. Their exoproteomes differed in either GroEL1 or DnaK abundance, depending on the interacting immune response.These findings point to an interdependent, tightly regulated response of MAP and the immune system.
Kristina J.H. Kleinwort; Stefanie M. Hauck; Roxane L. DeGroote; Armin M. Scholz; Christina Hölzel; Erwin P. Märtlbauer; Cornelia A. Deeg. Interplay of primary bovine lymphocytes and Mycobacterium avium subsp. paratuberculosis shows distinctly different proteome changes and immune pathways in host-pathogen interaction. 2019, 578187 .
AMA StyleKristina J.H. Kleinwort, Stefanie M. Hauck, Roxane L. DeGroote, Armin M. Scholz, Christina Hölzel, Erwin P. Märtlbauer, Cornelia A. Deeg. Interplay of primary bovine lymphocytes and Mycobacterium avium subsp. paratuberculosis shows distinctly different proteome changes and immune pathways in host-pathogen interaction. . 2019; ():578187.
Chicago/Turabian StyleKristina J.H. Kleinwort; Stefanie M. Hauck; Roxane L. DeGroote; Armin M. Scholz; Christina Hölzel; Erwin P. Märtlbauer; Cornelia A. Deeg. 2019. "Interplay of primary bovine lymphocytes and Mycobacterium avium subsp. paratuberculosis shows distinctly different proteome changes and immune pathways in host-pathogen interaction." , no. : 578187.
We report here the draft genome sequence of Acinetobacter junii MHI21018, isolated in 2009 from bovine colostrum. The draft genome sequence is composed of 3,267,995 bp, has a GC content of 38.54%, and was assembled into 114 contigs (contig size, >500 bp) with an N 50 value of 72,566 bp.
Carsten Kröger; Kristina Schauer; Seán R. Clerkin; Erwin Märtlbauer; Alastair B. Fleming. Draft Genome Sequence and Annotation of Acinetobacter junii MHI21018, Isolated from Bovine Colostrum. Microbiology Resource Announcements 2019, 8, e01700-18 .
AMA StyleCarsten Kröger, Kristina Schauer, Seán R. Clerkin, Erwin Märtlbauer, Alastair B. Fleming. Draft Genome Sequence and Annotation of Acinetobacter junii MHI21018, Isolated from Bovine Colostrum. Microbiology Resource Announcements. 2019; 8 (10):e01700-18.
Chicago/Turabian StyleCarsten Kröger; Kristina Schauer; Seán R. Clerkin; Erwin Märtlbauer; Alastair B. Fleming. 2019. "Draft Genome Sequence and Annotation of Acinetobacter junii MHI21018, Isolated from Bovine Colostrum." Microbiology Resource Announcements 8, no. 10: e01700-18.
Plant lectins bind to MAP with high affinity Several of these lectins showed no interference with milk and non-target bacteria Concanavalin A, lentil and banana lectin are able to bind to intact MAP cells
Bernhard F. Hobmaier; Karina Lutterberg; Kristina J.H. Kleinwort; Ricarda Mayer; Sieglinde Hirmer; Barbara Amann; Christina Hölzel; Erwin P. Märtlbauer; Cornelia A. Deeg. Characterization of plant lectins for their ability to isolate Mycobacterium avium subsp. paratuberculosis from milk. Food Microbiology 2019, 82, 231 -239.
AMA StyleBernhard F. Hobmaier, Karina Lutterberg, Kristina J.H. Kleinwort, Ricarda Mayer, Sieglinde Hirmer, Barbara Amann, Christina Hölzel, Erwin P. Märtlbauer, Cornelia A. Deeg. Characterization of plant lectins for their ability to isolate Mycobacterium avium subsp. paratuberculosis from milk. Food Microbiology. 2019; 82 ():231-239.
Chicago/Turabian StyleBernhard F. Hobmaier; Karina Lutterberg; Kristina J.H. Kleinwort; Ricarda Mayer; Sieglinde Hirmer; Barbara Amann; Christina Hölzel; Erwin P. Märtlbauer; Cornelia A. Deeg. 2019. "Characterization of plant lectins for their ability to isolate Mycobacterium avium subsp. paratuberculosis from milk." Food Microbiology 82, no. : 231-239.
Phycotoxins and mycotoxins, such as paralytic shellfish poisoning toxins, type A trichothecenes, and aflatoxins are among the most toxic low molecular weight toxins associated with human poisoning incidents through the consumption of naturally contaminated food. Therefore, there is an utmost need for rapid and sensitive on-site detection systems. Herein, an electrochemical biochip for fast detection of saxitoxin, T-2 toxin as well as aflatoxin M1 and their corresponding congeners, respectively, using a portable and fully automated detection platform (pBDi, portable BioDetector integrated) was developed. Toxin analysis is facilitated upon the biochip via an indirect competitive immunoassay using toxin-specific antibodies combined with anti-idiotypic antibodies. The developed biochips enable detection in the low ng/mL-range within 17 min. Moreover, the assays cover a wide linear working range of 2–3 orders of magnitude above the limit of detection with an inter-chip coefficient of variation lower than 15%. The broad specificity of the employed antibodies which react with a large number of congeners within the respective toxin group allows efficient screening of contaminated samples for the presence of these low molecular weight toxins. With respect to the analysis of human urine samples, we focused here on the detection of saxitoxin, HT-2 toxin, and aflatoxin M1, all known as biomarkers of acute toxin exposure. Overall, it was proved that the developed biochip assays can be used to rapidly and reliably identify severe intoxications caused by these low molecular weight toxins.
Katharina Schulz; Christopher Pöhlmann; Richard Dietrich; Erwin Märtlbauer; Thomas Elßner. Electrochemical Biochip Assays Based on Anti-idiotypic Antibodies for Rapid and Automated On-Site Detection of Low Molecular Weight Toxins. Frontiers in Chemistry 2019, 7, 31 .
AMA StyleKatharina Schulz, Christopher Pöhlmann, Richard Dietrich, Erwin Märtlbauer, Thomas Elßner. Electrochemical Biochip Assays Based on Anti-idiotypic Antibodies for Rapid and Automated On-Site Detection of Low Molecular Weight Toxins. Frontiers in Chemistry. 2019; 7 ():31.
Chicago/Turabian StyleKatharina Schulz; Christopher Pöhlmann; Richard Dietrich; Erwin Märtlbauer; Thomas Elßner. 2019. "Electrochemical Biochip Assays Based on Anti-idiotypic Antibodies for Rapid and Automated On-Site Detection of Low Molecular Weight Toxins." Frontiers in Chemistry 7, no. : 31.
The Bacillus (B.) cereus group consists of nine recognized species which are present worldwide. B. cereus play an important role in food-borne diseases by producing different toxins. Yet, only a small percentage of B. cereus strains are able to produce the heat stable cereulide, the causative agent of emetic food poisoning. To minimize the entry of emetic B. cereus into the food chain, food business operators are dependent on efficient and reliable methods enabling the differentiation between emetic and non-emetic strains. Currently, only time-consuming cell bioassays, molecular methods and tandem mass spectrometry are available for this purpose. Thus, the aim of the present study was to establish a fast and reliable method for the differentiation between emetic/non-emetic strains by MALDI-TOF MS. Selected strains/isolates of the B. cereus group as well as other Bacillus spp. (total n=121) were cultured on sheep blood agar for 48h before analysis. Subsequently, the cultures were directly analyzed by MALDI-TOF MS without prior extraction steps. The samples were measured in the mass range of m/z 800 – 1,800 Da. Using ClinProTools 3.0 statistical software and Flex analysis software (Bruker Daltonics GmbH, Bremen, Germany), a differentiation between emetic/non-emetic isolates was possible with a rate of correct identification of 99.1 % by means of the evaluation of two specific biomarkers (m/z 1171 and 1187 Da).
Sebastian Ulrich; Christoph Gottschalk; Richard Dietrich; Erwin Märtlbauer; Manfred Gareis. Identification of cereulide producing Bacillus cereus by MALDI-TOF MS. Food Microbiology 2019, 82, 75 -81.
AMA StyleSebastian Ulrich, Christoph Gottschalk, Richard Dietrich, Erwin Märtlbauer, Manfred Gareis. Identification of cereulide producing Bacillus cereus by MALDI-TOF MS. Food Microbiology. 2019; 82 ():75-81.
Chicago/Turabian StyleSebastian Ulrich; Christoph Gottschalk; Richard Dietrich; Erwin Märtlbauer; Manfred Gareis. 2019. "Identification of cereulide producing Bacillus cereus by MALDI-TOF MS." Food Microbiology 82, no. : 75-81.
Host recognition of microbial components is essential in mediating an effective immune response. Cytosolic bacteria must secure entry into the host cytoplasm to facilitate replication and, in doing so, liberate microbial ligands that activate cytosolic innate immune sensors and the inflammasome. Here, we identified a multicomponent enterotoxin, haemolysin BL (HBL), that engages activation of the inflammasome. This toxin is highly conserved among the human pathogen Bacillus cereus. The three subunits of HBL bind to the cell membrane in a linear order, forming a lytic pore and inducing activation of the NLRP3 inflammasome, secretion of interleukin-1β and interleukin-18, and pyroptosis. Mechanistically, the HBL-induced pore results in the efflux of potassium and triggers the activation of the NLRP3 inflammasome. Furthermore, HBL-producing B. cereus induces rapid inflammasome-mediated mortality. Pharmacological inhibition of the NLRP3 inflammasome using MCC950 prevents B. cereus-induced lethality. Overall, our results reveal that cytosolic sensing of a toxin is central to the innate immune recognition of infection. Therapeutic modulation of this pathway enhances host protection against deadly bacterial infections. The Bacillus cereus enterotoxin haemolysin BL induces pore formation and activation of the NLRP3 inflammasome, leading to enhanced lethality during infection.
Anukriti Mathur; Shouya Feng; Jenni Hayward; Chinh Ngo; Daniel Fox; Ines I. Atmosukarto; Jason D. Price; Kristina Schauer; Erwin Märtlbauer; Avril A. B. Robertson; Gaetan Burgio; Edward Fox; Stephen H. Leppla; Nadeem O. Kaakoush; Si Ming Man. A multicomponent toxin from Bacillus cereus incites inflammation and shapes host outcome via the NLRP3 inflammasome. Nature Microbiology 2018, 4, 362 -374.
AMA StyleAnukriti Mathur, Shouya Feng, Jenni Hayward, Chinh Ngo, Daniel Fox, Ines I. Atmosukarto, Jason D. Price, Kristina Schauer, Erwin Märtlbauer, Avril A. B. Robertson, Gaetan Burgio, Edward Fox, Stephen H. Leppla, Nadeem O. Kaakoush, Si Ming Man. A multicomponent toxin from Bacillus cereus incites inflammation and shapes host outcome via the NLRP3 inflammasome. Nature Microbiology. 2018; 4 (2):362-374.
Chicago/Turabian StyleAnukriti Mathur; Shouya Feng; Jenni Hayward; Chinh Ngo; Daniel Fox; Ines I. Atmosukarto; Jason D. Price; Kristina Schauer; Erwin Märtlbauer; Avril A. B. Robertson; Gaetan Burgio; Edward Fox; Stephen H. Leppla; Nadeem O. Kaakoush; Si Ming Man. 2018. "A multicomponent toxin from Bacillus cereus incites inflammation and shapes host outcome via the NLRP3 inflammasome." Nature Microbiology 4, no. 2: 362-374.