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Çürek S, Geniş B, Özden Tuncer B, Tuncer Y. Prevalence, Toxin Genes, and Antibiotic Resistance Profiles of Bacillus cereus Isolates from Spices in Antalya and Isparta Provinces in Türkiye. Indian J Microbiol 2023; 63:549-561. [PMID: 38031610 PMCID: PMC10682334 DOI: 10.1007/s12088-023-01111-7] [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: 08/03/2023] [Accepted: 10/07/2023] [Indexed: 12/01/2023] Open
Abstract
Bacillus cereus is a pathogenic bacterium commonly found in nature and can produce toxins that cause food poisoning. This study aimed to detect the prevalence of B. cereus group bacteria in 50 unpackaged and 20 packaged spice samples frequently used as flavoring in Turkish cuisine, as well as investigate the presence of toxin genes and antibiotic resistance in the isolates. A total of 48 B. cereus group bacteria were isolated from 27 of 70 (38.57%) spice samples. The prevalence of B. cereus group bacteria in packaged (25%, 5/20) and unpackaged (44%, 22/50) spice samples did not differ significantly (P ˃ 0.05). All B. cereus group isolates were identified as B. cereus sensu stricto (B. cereus) using molecular methods. The hemolytic activity tests revealed that the most strains (44/48, 91.67%) are β-hemolytic. The distributions of toxin genes in isolates were investigated by PCR. It was determined that all isolates were identified to have 2-8 toxin genes, except B. cereus SBC3. The three most common toxin genes were found to be nheA (47/48, 97.92%), nheB (46/48, 95.83%), and entFM (46/48, 95.83%). All B. cereus isolates were susceptible to linezolid and vancomycin, while 35.42% (17/48) showed resistance to erythromycin. Multi-drug resistance (MDR) was detected in 8.3% (4/48) of B. cereus isolates, while 33.33% of the isolates showed multiple antibiotic resistance (MAR) index values higher than 0.2. The findings indicate that B. cereus may pose a health risk in packaged and unpackaged spices if present in high quantities. Therefore, the presence of B. cereus strains in both packaged and unpackaged spices should be monitored regarding consumer health and product safety.
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Affiliation(s)
- Sena Çürek
- Faculty of Engineering, Department of Food Engineering, Süleyman Demirel University, Isparta, Türkiye
| | - Burak Geniş
- Faculty of Engineering, Department of Food Engineering, Süleyman Demirel University, Isparta, Türkiye
| | - Banu Özden Tuncer
- Faculty of Engineering, Department of Food Engineering, Süleyman Demirel University, Isparta, Türkiye
| | - Yasin Tuncer
- Faculty of Engineering, Department of Food Engineering, Süleyman Demirel University, Isparta, Türkiye
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Oliveira M, Carvalho M, Teixeira P. Characterization of the Toxigenic Potential of Bacillus cereus sensu lato Isolated from Raw Berries and Their Products. Foods 2023; 12:4021. [PMID: 37959140 PMCID: PMC10648475 DOI: 10.3390/foods12214021] [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: 10/11/2023] [Revised: 10/29/2023] [Accepted: 10/30/2023] [Indexed: 11/15/2023] Open
Abstract
Bacillus cereus is estimated to be responsible for 1.4-12% of all food poisoning outbreaks worldwide. The objective of this study was to investigate the toxigenic potential of 181 isolates of B. cereus previously recovered from different types of berries and berry products (strawberries, raspberries, blackberries, and blueberries) by assessing the presence of enterotoxin genes (hblA, hblC, hblD, nheA, nheB, nheC, and cytK) and an emetic toxin cereulide synthetase gene (ces). The cytotoxic activity on Caco-2 cells was also evaluated for the two isolates containing the gene cytK. Twenty-three toxigenic profiles were found. The nheABC (91.7%) and hblACD (89.0%) complexes were the most prevalent among the isolates, while the cytK and ces genes were detected in low percentages, 1.1% and 3.3%, respectively. In addition, the nheABC/hblACD complex and ces genes were detected in isolates recovered throughout the production process of blackberries and strawberries. The cytotoxic activity on Caco-2 cells was also observed to be greater than 60% for isolates containing the cytK gene.
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Affiliation(s)
- Márcia Oliveira
- Department of Food Hygiene and Technology, University of León, 24071 León, Spain;
| | - Marta Carvalho
- Laboratório Associado, CBQF—Centro de Biotecnologia e Química Fina, Escola Superior de Biotecnologia, Universidade Católica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal;
| | - Paula Teixeira
- Laboratório Associado, CBQF—Centro de Biotecnologia e Química Fina, Escola Superior de Biotecnologia, Universidade Católica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal;
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Yang H, Yeom W, Oh J, Kim H, Beuchat LR, Ryu JH. Antimicrobial effects of essential oil vapors on Bacillus cereus on nutrient agar and iceberg lettuce. FOOD BIOSCI 2023. [DOI: 10.1016/j.fbio.2023.102580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
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4
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Hu R, Hu A, Lu Z, Zhou H, Wei W, Lu F, Zhao H, Bie X. Construction and optimization of a multiplex PMAxx-qPCR assay for viable Bacillus cereus and development of a detection kit. J Microbiol Methods 2023; 207:106705. [PMID: 36914099 DOI: 10.1016/j.mimet.2023.106705] [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: 05/20/2022] [Revised: 03/09/2023] [Accepted: 03/09/2023] [Indexed: 03/13/2023]
Abstract
In this study, a PMAxx-qPCR method for the detection and quantification of viable Bacillus cereus (B. cereus) was established based on the cesA gene that is involved in cereulide synthesis, enterotoxin gene bceT and hemolytic enterotoxin gene hblD combined with modified propidium monoazide (PMAxx). The sensitivity detection limit of the method was as follows: the DNA extracted by the kit reached 140 fg/μL, and the bacterial suspension without enrichment reached 2.24 × 101 CFU/mL; 14 nonB. cereus strains of the 17 tested strains all tested as negative, whereas the 2 strains of B. cereus carrying the target virulence gene(s) could be accurately detected. In terms of application, we assembled the constructed PMAxx-qPCR reaction into a detection kit and evaluated its application performance. The results showed that the detection kit has high sensitivity, strong anti-interference capability, and has good application potential. The purpose of this study is to provide a reliable detection method for the prevention and traceability of B. cereus infections.
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Affiliation(s)
- Ruirui Hu
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Xuanwu District, Nanjing, Jiangsu, China
| | - Antuo Hu
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Xuanwu District, Nanjing, Jiangsu, China
| | - Zhaoxin Lu
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Xuanwu District, Nanjing, Jiangsu, China
| | - Haibo Zhou
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Xuanwu District, Nanjing, Jiangsu, China
| | - Wanqing Wei
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Xuanwu District, Nanjing, Jiangsu, China
| | - Fengxia Lu
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Xuanwu District, Nanjing, Jiangsu, China
| | - Haizhen Zhao
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Xuanwu District, Nanjing, Jiangsu, China
| | - Xiaomei Bie
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Xuanwu District, Nanjing, Jiangsu, China.
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5
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Huang L, Hwang CA. One-step dynamic analysis of growth kinetics of Bacillus cereus from spores in simulated fried rice – Model development, validation, and Marko Chain Monte Carlo simulation. Food Microbiol 2022; 103:103935. [DOI: 10.1016/j.fm.2021.103935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 11/03/2021] [Accepted: 11/03/2021] [Indexed: 11/04/2022]
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Jovanovic J, Tretiak S, Begyn K, Rajkovic A. Detection of Enterotoxigenic Psychrotrophic Presumptive Bacillus cereus and Cereulide Producers in Food Products and Ingredients. Toxins (Basel) 2022; 14:toxins14040289. [PMID: 35448897 PMCID: PMC9030337 DOI: 10.3390/toxins14040289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 04/07/2022] [Accepted: 04/13/2022] [Indexed: 02/04/2023] Open
Abstract
In the last decade, foodborne outbreaks and individual cases caused by bacterial toxins showed an increasing trend. The major contributors are enterotoxins and cereulide produced by Bacillus cereus, which can cause a diarrheal and emetic form of the disease, respectively. These diseases usually induce relatively mild symptoms; however, fatal cases have been reported. With the aim to detected potential toxin producers that are able to grow at refrigerator temperatures and subsequently produce cereulide, we screened the prevalence of enterotoxin and cereulide toxin gene carriers and the psychrotrophic capacity of presumptive B. cereus obtained from 250 food products (cereal products, including rice and seeds/pulses, dairy-based products, dried vegetables, mixed food, herbs, and spices). Of tested food products, 226/250 (90.4%) contained presumptive B. cereus, which communities were further tested for the presence of nheA, hblA, cytK-1, and ces genes. Food products were mainly contaminated with the nheA B. cereus carriers (77.9%), followed by hblA (64.8%), ces (23.2%), and cytK-1 (4.4%). Toxigenic B. cereus communities were further subjected to refrigerated (4 and 7 °C) and mild abuse temperatures (10 °C). Overall, 77% (94/121), 86% (104/121), and 100% (121/121) were able to grow at 4, 7, and 10 °C, respectively. Enterotoxin and cereulide potential producers were detected in 81% of psychrotrophic presumptive B. cereus. Toxin encoding genes nheA, hblA, and ces gene were found in 77.2, 55, and 11.7% of tested samples, respectively. None of the psychrotrophic presumptive B. cereus were carriers of the cytotoxin K-1 encoding gene (cytK-1). Nearly half of emetic psychrotrophic B. cereus were able to produce cereulide in optimal conditions. At 4 °C none of the examined psychrotrophs produced cereulide. The results of this research highlight the high prevalence of B. cereus and the omnipresence of toxin gene harboring presumptive B. cereus that can grow at refrigerator temperatures, with a focus on cereulide producers.
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Affiliation(s)
- Jelena Jovanovic
- Department of Food Technology, Safety, and Health, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; (J.J.); (K.B.)
| | - Svitlana Tretiak
- Department of Pathobiology, Pharmacology and Zoological Medicine, Ghent University, Salisburylaan 133, D5 Ingang 78, 9820 Merelbeke, Belgium;
- Impextraco nv, Wiekevorstsesteenweg 38, 2220 Heist-op-den-Berg, Belgium
| | - Katrien Begyn
- Department of Food Technology, Safety, and Health, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; (J.J.); (K.B.)
| | - Andreja Rajkovic
- Department of Food Technology, Safety, and Health, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; (J.J.); (K.B.)
- Correspondence:
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Etikala A, Thamburaj S, Johnson AM, Sarma C, Mummaleti G, Kalakandan SK. Incidence, toxin gene profile, antibiotic resistance and antibacterial activity of Allium parvum and Allium cepa extracts on Bacillus cereus isolated from fermented millet-based food. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Tariq M, Jameel F, Ijaz U, Abdullah M, Rashid K. Biofertilizer microorganisms accompanying pathogenic attributes: a potential threat. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2022; 28:77-90. [PMID: 35221573 PMCID: PMC8847475 DOI: 10.1007/s12298-022-01138-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 11/30/2021] [Accepted: 01/14/2022] [Indexed: 05/04/2023]
Abstract
Application of biofertilizers containing living or dormant plant growth promoting bacterial cells is considered to be an ecofriendly alternative of chemical fertilizers for improved crop production. Biofertilizers opened myriad doors towards sustainable agriculture as they effectively reduce heavy use of chemical fertilizers and pesticides by keeping soils profuse in micro and macronutrients, regulating plant hormones and restraining infections caused by the pests present in soil without inflicting environmental damage. Generally, pathogenicity and biosafety testing of potential plant growth promoting bacteria (PGPB) are not performed, and the bacteria are reported to be beneficial solely on testing plant growth promoting characteristics. Unfortunately, some rhizosphere and endophytic PGPB are reported to be involved in various diseases. Such PGPB can also spread virulence and multidrug resistance genes carried by them through horizontal gene transfer to other bacteria in the environment. Therefore, deployment of such microbial populations in open fields could lead to disastrous side effects on human health and environment. Careless declaration of bacteria as PGPB is more pronounced in research publications. Here, we present a comprehensive report of declared PGPB which are reported to be pathogenic in other studies. This review also suggests the employment of some additional safety assessment protocols before reporting a bacteria as beneficial and product development.
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Affiliation(s)
- Mohsin Tariq
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Farwah Jameel
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan
- National Institute for Biotechnology and Genetic Engineering, Faisalabad, Pakistan
| | - Usman Ijaz
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Muhammad Abdullah
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Kamran Rashid
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan
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10
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Jovanovic J, Ornelis VFM, Madder A, Rajkovic A. Bacillus cereus food intoxication and toxicoinfection. Compr Rev Food Sci Food Saf 2021; 20:3719-3761. [PMID: 34160120 DOI: 10.1111/1541-4337.12785] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 05/13/2021] [Accepted: 05/15/2021] [Indexed: 12/12/2022]
Abstract
Bacillus cereus is one of the leading etiological agents of toxin-induced foodborne diseases. Its omnipresence in different environments, spore formation, and its ability to adapt to varying conditions and produce harmful toxins make this pathogen a health hazard that should not be underestimated. Food poisoning by B. cereus can manifest itself as an emetic or diarrheal syndrome. The former is caused by the release of the potent peptide toxin cereulide, whereas the latter is the result of proteinaceous enterotoxins (e.g., hemolysin BL, nonhemolytic enterotoxin, and cytotoxin K). The final harmful effect is not only toxin and strain dependent, but is also affected by the stress responses, accessory virulence factors, and phenotypic properties under extrinsic, intrinsic, and explicit food conditions and host-related environment. Infamous portrait of B. cereus as a foodborne pathogen, as well as a causative agent of nongastrointestinal infections and even nosocomial complications, has inspired vast volumes of multidisciplinary research in food and clinical domains. As a result, extensive original data became available asking for a new, both broad and deep, multifaceted look into the current state-of-the art regarding the role of B. cereus in food safety. In this review, we first provide an overview of the latest knowledge on B. cereus toxins and accessory virulence factors. Second, we describe the novel taxonomy and some of the most pertinent phenotypic characteristics of B. cereus related to food safety. We link these aspects to toxin production, overall pathogenesis, and interactions with its human host. Then we reflect on the prevalence of different toxinotypes in foods opening the scene for epidemiological aspects of B. cereus foodborne diseases and methods available to prevent food poisoning including overview of the different available methods to detect B. cereus and its toxins.
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Affiliation(s)
- Jelena Jovanovic
- Department of Food Technology, Safety and Health, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Vincent F M Ornelis
- Department of Organic and Macromolecular Chemistry, Faculty of Sciences, Ghent University, Ghent, Belgium
| | - Annemieke Madder
- Department of Organic and Macromolecular Chemistry, Faculty of Sciences, Ghent University, Ghent, Belgium
| | - Andreja Rajkovic
- Department of Food Technology, Safety and Health, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
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Abstract
Foodborne diseases have been witnessing a constant rising trend worldwide, mainly caused by pathogenic microorganisms, such as Bacillus spp., posing a direct threat to public health. The purpose of this study was to evaluate the biological risk of foodborne and probiotic Bacillus spp. in Beijing markets. A total of 55 Bacillus isolates, including 29 B. cereus, 9 B. licheniformis and 7 B. subtilis, mostly found in dairy products (32.7%), were recovered from 106 samples and identified by matrix-assisted laser desorption/ionization mass spectrometry and polymerase chain reaction methods. The susceptibility towards 16 antibiotics was determined using a broth microdilution method. Bacillus showed a high level of resistance to florfenicol (100%), lincomycin (100%), tiamulin (78.2%) and ampicillin (67.3%), while they were all susceptible or intermediate to vancomycin and rifampin. Additionally, we obtained the whole genome of 19 Bacillus strains using high-throughput sequencing, and the rates of resistance genes van, fosB, erm and tet were 57.9%, 57.9%, 21.1% and 26.3%, respectively. Moreover, 100%, 9.1%, 45.5% and 100% of these isolates carried virulence genes nhe, hbl, cytK and entFM, respectively. Lastly, 60% Bacillus strains were positive in hemolysis tests, and 3 B. licheniformis strains displayed an inhibitory activity on the growth of S. aureus ATCC 29213 using agar overlay technique. Our study outlines the characteristics of foodborne Bacillus spp. and provides information for the monitoring of food safety.
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Jung S, Woo C, Fugaban JII, Vazquez Bucheli JE, Holzapfel WH, Todorov SD. Bacteriocinogenic Potential of Bacillus amyloliquefaciens Isolated from Kimchi, a Traditional Korean Fermented Cabbage. Probiotics Antimicrob Proteins 2021; 13:1195-1212. [PMID: 33721203 DOI: 10.1007/s12602-021-09772-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/05/2021] [Indexed: 12/24/2022]
Abstract
Bacteriocin production is considered a favorable property for various beneficial cultures. In addition to their potential as biopreservatives, bacteriocins are also promising alternatives for the control of multidrug-resistant pathogens and the inhibition of some viruses and cancer cells. The objective of this study was to screen and characterize a bacteriocin-producing strain with the aim of its future application for control of Listeria monocytogenes, an important food-borne pathogen. A total of 22 potentially bacteriocinogenic strains active against L. monocytogenes ATCC15313 were isolated from locally produced kimchi through a three-level approach. Pure cultures were obtained according to good microbiological practices and differentiated through RAPD-PCR using the primers OPL01, OPL09, and OPL11. Altogether, 5 strains were selected for further study. Specific focus was given to strain ST05DL based on its specific inhibitory activity against L. monocytogenes ATCC15313, while not affecting different strains belonging to the genera Lactobacillus, Pediococcus, Leuconostoc, and Weissella, most of which are beneficial microorganisms. The strain ST05DL was identified as Bacillus amyloliquefaciens based on its sugar fermentation profile obtained through API50CHB analysis and 16S rRNA partial sequencing. The antimicrobial compound produced by B. amyloliquefaciens ST05DL was found to be sensitive to pepsin and α-chymotrypsin, evidence of its proteinaceous nature. The presence of skim milk, NaCl, Tween 80, glycerol, and SDS did not affect the antimicrobial activity. The addition of 20% cell-free supernatant (CFS) obtained from a 24-h culture of B. amyloliquefaciens ST05DL to an exponentially growing culture of L. monocytogenes ATCC15313 successfully inhibited the test microorganisms during the monitored 10-h incubation. Optimal bacteriocin production by B. amyloliquefaciens ST05DL was observed during the stationary phase at 12 h (800 AU/mL) and remained stable for the next 15 h. The ratio between live and dead cells during this period was 74.37% and 25.66%, respectively, as determined by flow cytometry. The presence of the virulence genes hblA, hblB, hblC, nheA, nheB, and nheC was not detected in the total DNA of B. amyloliquefaciens ST05DL, and the strain was resistant only to ampicillin out of 10 tested antibiotics. Future evaluation of expressed bacteriocin/s by B. amyloliquefaciens ST05DL (amino acid sequence, molecular mass, cytotoxicity, detailed mode of action, etc.), will be the next step in the characterization and its potential application as biopreservative and/or pharmaceutical product.
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Affiliation(s)
- Sungmin Jung
- ProBacLab, Graduate School of Advanced Convergence, Handong Global University, Pohang, Gyeongbuk, 37554, Republic of Korea
| | - Chaerin Woo
- ProBacLab, Graduate School of Advanced Convergence, Handong Global University, Pohang, Gyeongbuk, 37554, Republic of Korea
| | - Joanna Ivy Irorita Fugaban
- ProBacLab, Graduate School of Advanced Convergence, Handong Global University, Pohang, Gyeongbuk, 37554, Republic of Korea
| | - Jorge Enrique Vazquez Bucheli
- ProBacLab, Graduate School of Advanced Convergence, Handong Global University, Pohang, Gyeongbuk, 37554, Republic of Korea
| | - Wilhelm Heinrich Holzapfel
- ProBacLab, Graduate School of Advanced Convergence, Handong Global University, Pohang, Gyeongbuk, 37554, Republic of Korea
| | - Svetoslav Dimitrov Todorov
- ProBacLab, Graduate School of Advanced Convergence, Handong Global University, Pohang, Gyeongbuk, 37554, Republic of Korea.
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The Food Poisoning Toxins of Bacillus cereus. Toxins (Basel) 2021; 13:toxins13020098. [PMID: 33525722 PMCID: PMC7911051 DOI: 10.3390/toxins13020098] [Citation(s) in RCA: 99] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/14/2021] [Accepted: 01/25/2021] [Indexed: 12/13/2022] Open
Abstract
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.
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Jessberger N, Dietrich R, Granum PE, Märtlbauer E. The Bacillus cereus Food Infection as Multifactorial Process. Toxins (Basel) 2020; 12:E701. [PMID: 33167492 PMCID: PMC7694497 DOI: 10.3390/toxins12110701] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 10/30/2020] [Accepted: 11/02/2020] [Indexed: 02/06/2023] Open
Abstract
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.
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Affiliation(s)
- Nadja Jessberger
- Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität München, Schönleutnerstr. 8, 85764 Oberschleißheim, Germany; (R.D.); (E.M.)
| | - Richard Dietrich
- Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität München, Schönleutnerstr. 8, 85764 Oberschleißheim, Germany; (R.D.); (E.M.)
| | - Per Einar Granum
- Department of Food Safety and Infection Biology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, P.O. Box 5003 NMBU, 1432 Ås, Norway;
| | - Erwin Märtlbauer
- Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität München, Schönleutnerstr. 8, 85764 Oberschleißheim, Germany; (R.D.); (E.M.)
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15
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Kim S, Kim S. Bacterial pathogen detection by conventional culture‐based and recent alternative (polymerase chain reaction, isothermal amplification, enzyme linked immunosorbent assay, bacteriophage amplification, and gold nanoparticle aggregation) methods in food samples: A review. J Food Saf 2020. [DOI: 10.1111/jfs.12870] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Sang‐Oh Kim
- Department of Plant and Food Sciences Sangmyung University Cheonan Republic of Korea
| | - Sang‐Soon Kim
- Department of Food Engineering Dankook University Cheonan Republic of Korea
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Park KM, Kim HJ, Jeong M, Koo M. Enterotoxin Genes, Antibiotic Susceptibility, and Biofilm Formation of Low-Temperature-Tolerant Bacillus cereus Isolated from Green Leaf Lettuce in the Cold Chain. Foods 2020; 9:foods9030249. [PMID: 32106606 PMCID: PMC7142467 DOI: 10.3390/foods9030249] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/20/2020] [Accepted: 02/25/2020] [Indexed: 12/25/2022] Open
Abstract
The prevalence and characteristics of low-temperature-tolerant Bacillus cereus (psychrotolerant B. cereus) in green leaf lettuce collected during cold chain were investigated. Among the 101 isolated B. cereus samples, only 18 were capable of growth at 7 °C, and these isolates shared potential health hazard characteristics with mesophilic isolates. Most psychrotolerant B. cereus isolates contained various combinations of nheA, nheB, nheC, hblA, hblA, hblC, hblD, cytK, and entFM. Most isolates of psychrotolerant B. cereus possessed at least two enterotoxin genes and 28% of isolates harbored tested nine enterotoxin genes. Additionally, the psychrotolerant B. cereus isolates showed resistance to tetracycline and rifampin and intermediate levels of resistance to clindamycin. A total of 23% of isolates among psychrotolerant B. cereus displayed a high level of biofilm formation at 7 °C than at 10 °C or 30 °C. The results of this study indicate that cold distribution and storage for green leaf lettuce may fail to maintain food safety due to the presence of enterotoxigenic, antibiotic-resistant, and strong biofilm forming psychrotolerant B. cereus isolates, which therefore poses a potential health risk to the consumer. Our findings provide the first account of the prevalence and characteristics of psychrotolerant B. cereus isolated from green leaf lettuce during cold storage, suggesting a potential hazard of psychrotolerant B. cereus isolates to public health and the food industry.
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Affiliation(s)
- Kyung Min Park
- Food Biotechnology, Korea University of Science & Technology, Daejeon 34113, Korea; (K.M.P.); (H.J.K.)
- Consumer Safety, Korea Food Research Institute, Wanju-gun 55365, Korea;
| | - Hyun Jung Kim
- Food Biotechnology, Korea University of Science & Technology, Daejeon 34113, Korea; (K.M.P.); (H.J.K.)
- Consumer Safety, Korea Food Research Institute, Wanju-gun 55365, Korea;
| | - Mooncheol Jeong
- Consumer Safety, Korea Food Research Institute, Wanju-gun 55365, Korea;
| | - Minseon Koo
- Food Biotechnology, Korea University of Science & Technology, Daejeon 34113, Korea; (K.M.P.); (H.J.K.)
- Food Analysis Center, Korea Food Research Institute, Wanju-gun 55365, Korea
- Correspondence: ; Tel.: +82-63-219-9161; Fax: +82-63-219-9876
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17
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The cereus matter of Bacillus endophthalmitis. Exp Eye Res 2020; 193:107959. [PMID: 32032628 DOI: 10.1016/j.exer.2020.107959] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 01/06/2020] [Accepted: 02/03/2020] [Indexed: 02/06/2023]
Abstract
Bacillus cereus (B. cereus) endophthalmitis is a devastating intraocular infection primarily associated with post-traumatic injuries. The majority of these infections result in substantial vision loss, if not loss of the eye itself, within 12-48 h. Multifactorial mechanisms that lead to the innate intraocular inflammatory response during this disease include the combination of robust bacterial replication, migration of the organism throughout the eye, and toxin production by the organism. Therefore, the window of therapeutic intervention in B. cereus endophthalmitis is quite narrow compared to that of other pathogens which cause this disease. Understanding the interaction of bacterial and host factors is critical in understanding the disease and formulating more rational therapeutics for salvaging vision. In this review, we will discuss clinical and research findings related to B. cereus endophthalmitis in terms of the organism's virulence and inflammogenic potential, and strategies for improving of current therapeutic regimens for this blinding disease.
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18
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Yu S, Yu P, Wang J, Li C, Guo H, Liu C, Kong L, Yu L, Wu S, Lei T, Chen M, Zeng H, Pang R, Zhang Y, Wei X, Zhang J, Wu Q, Ding Y. A Study on Prevalence and Characterization of Bacillus cereus in Ready-to-Eat Foods in China. Front Microbiol 2020; 10:3043. [PMID: 32010099 PMCID: PMC6974471 DOI: 10.3389/fmicb.2019.03043] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 12/17/2019] [Indexed: 12/24/2022] Open
Abstract
Bacillus cereus is widely distributed in different food products and can cause a variety of symptoms associated with food poisoning. Since ready-to-eat (RTE) foods are not commonly sterilized by heat treatment before consumption, B. cereus contamination may cause severe food safety problems. In this study, we investigated the prevalence of B. cereus in RTE food samples from different regions of China and evaluated the levels of bacterial contamination, antibiotic resistance, virulence gene distribution, and genetic polymorphisms of these isolates. Of the tested retail RTE foods, 35% were positive for B. cereus, with 39 and 83% of the isolated strains harboring the enterotoxin-encoding hblACD and nheABC gene clusters, respectively. The entFM gene was detected in all B. cereus strains. The cytK gene was present in 68% of isolates, but only 7% harbored the emetic toxin-encoding gene cesB. Antimicrobial susceptibility testing revealed that the majority of the isolates were resistant not only to most β-lactam antibiotics, but also to rifamycin. Multilocus sequence typing (MLST) revealed that the 368 isolates belonged to 192 different sequence types (STs) including 93 new STs, the most prevalent of which was ST26. Collectively, our study indicates the prevalence, bacterial contamination levels, and biological characteristics of B. cereus isolated from RTE foods in China and demonstrates the potential hazards of B. cereus in RTE foods.
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Affiliation(s)
- Shubo Yu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Pengfei Yu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China.,Department of Food Science and Technology, Institute of Food Safety and Nutrition, Jinan University, Guangzhou, China
| | - Juan Wang
- College of Food Science, South China Agricultural University, Guangzhou, China
| | - Chun Li
- Department of Food Science and Technology, Institute of Food Safety and Nutrition, Jinan University, Guangzhou, China
| | - Hui Guo
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China.,Department of Food Science and Technology, Institute of Food Safety and Nutrition, Jinan University, Guangzhou, China
| | - Chengcheng Liu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China.,Department of Food Science and Technology, Institute of Food Safety and Nutrition, Jinan University, Guangzhou, China
| | - Li Kong
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China.,Department of Food Science and Technology, Institute of Food Safety and Nutrition, Jinan University, Guangzhou, China
| | - Leyi Yu
- Department of Food Science and Technology, Institute of Food Safety and Nutrition, Jinan University, Guangzhou, China
| | - Shi Wu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Tao Lei
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Moutong Chen
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Haiyan Zeng
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Rui Pang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Youxiong Zhang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Xianhu Wei
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Jumei Zhang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Qingping Wu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Yu Ding
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China.,Department of Food Science and Technology, Institute of Food Safety and Nutrition, Jinan University, Guangzhou, China
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19
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Berhilevych O, Pylypenko L, Kasianchuk V, Ilyeva A, Shubin P. IDENTIFICATION OF FOOD PATHOGENS AND DETERMINATION OF THEIR DISTRIBUTION LEVEL IN UKRAINIAN FOOD PRODUCTS OF ANIMAL AND PLANT ORIGIN BY PCR METHOD. FOOD SCIENCE AND TECHNOLOGY 2019. [DOI: 10.15673/fst.v13i4.1562] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The foodborne pathogens cause serious public health problems in each country. In this regard, microbiological investigation is included in food safety management of the food chain. Molecular methods and mostly polymerase chain reaction (PCR) are considered highly sensitive, specific and rapid methods for pathogens detection from raw material and food. This study describes the using of specially designed and highly specific primers for PCR to identify 5 common and especially dangerous causeve agents of food poisoning and disease and to determine their level of distribution in food of animal and plant origin. The studies included the identification of methicillin-resistant Staphylococcus aureus (MRSA) and Cronobacter spp. (E. sakazakii) from raw milk, Shiga toxin-producing strains of Escherichia coli (STEC) from beef and swine carcasses, Bacillus cereus and Clostridium perfringens from various types of plant and animal raw materials and products of its processing - fruits, vegetables, berries, dried and preserved products, food concentrates, half-canned food. A total of 397 food samples were investigated to detect these pathogens using classical bacteriological methods and PCR. It was found that the distribution of foodborne pathogens in the studied products of animal and plant origin was as follows: Staphylococcus aureus (MRSA) and Cronobacterspp. (E. sakazakii) in raw cow milk in 6.5% and 19.4% of cases, respectively; shiga-toxin-producing Escherichia coli (STEC) from beef and pork carcasses in 8.1% and 5.7%; Bacillus cereus and Clostridium perfringens from different types of plant and animal raw materials and their processing products averages 27.5 % and 7.7 %, respectively. The advantages of molecular biological methods to which the PCR method relates, include their speed, as well as the specificity of identification of microorganisms by the features of genetic regions of genes that carry information about their pathogenicity factors. It has been found that the rate of detection of these pathogens when using the PCR method in comparison with classical methods increases at least 5-9 times. This data will be useful for assessing microbiological risk and will help authorities develop strategies to reduce consumer health risks.
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20
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Guérin A, Dargaignaratz C, Clavel T, Broussolle V, Nguyen-the C. Impact of temperature and oxygen on the fate of Bacillus weihenstephanensis in a food-based medium. Food Microbiol 2019; 83:175-180. [DOI: 10.1016/j.fm.2019.05.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 04/30/2019] [Accepted: 05/22/2019] [Indexed: 10/26/2022]
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21
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Hock L, Leprince A, Tournay M, Gillis A, Mahillon J. Biocontrol potential of phage Deep-Blue against psychrotolerant Bacillus weihenstephanensis. Food Control 2019. [DOI: 10.1016/j.foodcont.2019.03.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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22
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Osman KM, Kappell AD, Orabi A, Al-Maary KS, Mubarak AS, Dawoud TM, Hemeg HA, Moussa IMI, Hessain AM, Yousef HMY, Hristova KR. Poultry and beef meat as potential seedbeds for antimicrobial resistant enterotoxigenic Bacillus species: a materializing epidemiological and potential severe health hazard. Sci Rep 2018; 8:11600. [PMID: 30072706 PMCID: PMC6072766 DOI: 10.1038/s41598-018-29932-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 07/18/2018] [Indexed: 12/17/2022] Open
Abstract
Although Bacillus cereus is of particular concern in food safety and public health, the role of other Bacillus species was overlooked. Therefore, we investigated the presence of eight enterotoxigenic genes, a hemolytic gene and phenotypic antibiotic resistance profiles of Bacillus species in retail meat samples. From 255 samples, 124 Bacillus isolates were recovered, 27 belonged to B. cereus and 97 were non-B. cereus species. Interestingly, the non-B. cereus isolates carried the virulence genes and exhibited phenotypic virulence characteristics as the B. cereus. However, correlation matrix analysis revealed the B. cereus group positively correlates with the presence of the genes hblA, hblC, and plc, and the detection of hemolysis (p < 0.05), while the other Bacillus sp. groups are negatively correlated. Tests for antimicrobial resistance against ten antibiotics revealed extensive drug and multi-drug resistant isolates. Statistical analyses didn't support a correlation of antibiotic resistance to tested virulence factors suggesting independence of these phenotypic markers and virulence genes. Of special interest was the isolation of Paenibacillus alvei and Geobacillus stearothermophilus from the imported meat samples being the first recorded. The isolation of non-B. cereus species carrying enterotoxigenic genes in meat within Egypt, suggests their impact on food safety and public health and should therefore not be minimised, posing an area that requires further research.
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Affiliation(s)
- Kamelia M Osman
- Department of Microbiology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
| | - Anthony D Kappell
- Department of Civil, Construction, and Environmental Engineering, Marquette University, Milwaukee, WI, USA
| | - Ahmed Orabi
- Department of Microbiology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
| | - Khalid S Al-Maary
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Ayman S Mubarak
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Turki M Dawoud
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Hassan A Hemeg
- Department of Clinical Laboratory sciences, college of Applied Medical sciences, Taibah University, Taibah, Saudi Arabia
| | - Ihab M I Moussa
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Ashgan M Hessain
- Department of Health Science, College of Applied Studies and Community Service, King Saud University, Riyadh, Saudi Arabia
| | - Hend M Y Yousef
- Central Administration of Preventive Medicine, General Organization for Veterinary Service, Giza, Egypt.
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23
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Wei S, Chelliah R, Park BJ, Park JH, Forghani F, Park YS, Cho MS, Park DS, Oh DH. Molecular discrimination of Bacillus cereus group species in foods (lettuce, spinach, and kimbap) using quantitative real-time PCR targeting groEL and gyrB. Microb Pathog 2018; 115:312-320. [PMID: 29306007 DOI: 10.1016/j.micpath.2017.12.079] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 12/29/2017] [Accepted: 12/30/2017] [Indexed: 01/06/2023]
Abstract
The aim of the study was to identify and evaluate specific biomarkers to differentiate within Bacillus cereus group species from contaminated food samples with the use of real-time PCR. A total of 120 strains, comprising of 28 reference, 2 type, 78 wild strains of B. cereus and B. thuringiensis along with 12 strains representing 2 bacterial groups - B. mycoides, B. pseudomycoides, B. weihenstephanensis (B. cereus group); B. amyloliquefaciens, B. subtilis, Enterococcus faecalis, Escherichia coli, Listeria monocytogenes, Micrococcus luteus, Salmonella enterica, Staphylococcus aureus, Streptococcus pyogenes (non-Bacillus sp.) were identified by applying valid biomarkers (groEL and gyrB). In addition, the presence of B. cereus group was determined in three different artificially contaminated vegetable samples (lettuce, spinach, and kimbap), using prominent biomarkers targeting on chaperonin protein (GroEL) and topoisomerase enzyme protein (gyrB). Direct analysis of samples revealed the specificity towards identification and characterization of the B. cereus group among wild, reference and type strains and the type strain inoculated in vegetables. Our results demonstrated two existing biomarkers groEL and gyrB with a high specificity of 98% and 96% respectively to analyze the total B. cereus group. Further, we also reported the detection limit of groEL and gyrB in food samples was 3.5 and 3.7 log CFU/g respectively. Thus, the developed real-time PCR approach can be a reliable and effective tool for the identification of B. cereus group strains present in environment and food samples. This does not require band isolation, re-amplification, sequencing or sequence identification, thus reducing the time and cost of analysis.
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Affiliation(s)
- Shuai Wei
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Ramachandran Chelliah
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Byung-Jae Park
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Joong-Hyun Park
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Fereidoun Forghani
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Youn-Seo Park
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Min-Seok Cho
- Department of Agricultural Biotechnology, National Academy of Agricultural Science, Rural Development Administration, Jeonju, 54874, Republic of Korea
| | - Dong-Suk Park
- Department of Agricultural Biotechnology, National Academy of Agricultural Science, Rural Development Administration, Jeonju, 54874, Republic of Korea
| | - Deog-Hwan Oh
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, 24341, Republic of Korea.
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24
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Unique biomarkers as a potential predictive tool for differentiation of Bacillus cereus group based on real-time PCR. Microb Pathog 2017; 115:131-137. [PMID: 29274457 DOI: 10.1016/j.micpath.2017.12.055] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 12/11/2017] [Accepted: 12/19/2017] [Indexed: 11/20/2022]
Abstract
The aim of the study was to develop unique biomarkers for qPCR detection of Bacillus cereus group. Clinical and soil isolates were identified by specifically designed biomarkers - Lipoprotein (OPL-114-lipo), Methyltransferase (MT-17) and S-layer homology domain protein (151-1BC). In order to design biomarkers, we used 120 bacterial strains grouped into B. cereus and non-Bacillus group. The B. cereus group was confirmed by 108 strains of B. cereus and B. thuringiensis (30 reference and 78 wild), along with 3 strains of B. mycoides, B. pseudomycoides, and B. weihenstephanensis; while the non-Bacillus group was composed of 9 Gram-positive and Gram-negative strains. Direct analysis of samples revealed specificity towards identification and characterization of B. cereus group. The newly developed markers OPL-114-lipo and MT-17 showed specificity of 95% and 81%, respectively in identification of B. cereus. They are efficient tools to identify contaminated sources and the degree of bacterial contamination. Environmental and food samples do not require band isolation, re-amplification, sequencing or sequence identification. Thus, reducing the time and cost of analysis. Hence, it will be an alternative approach to traditional culture methods. Commercial food processing industries will be able to employ these biomarkers specific for B. cereus group as a detection tool to reduce economic loss due to B. cereus contamination.
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25
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Chelliah R, Wei S, Park BJ, Kim SH, Park DS, Kim SH, Hwan KS, Oh DH. Novel motB as a potential predictive tool for identification of B. cereus, B. thuringiensis and differentiation from other Bacillus species by triplex real-time PCR. Microb Pathog 2017; 111:22-27. [PMID: 28778821 DOI: 10.1016/j.micpath.2017.07.050] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2017] [Revised: 06/28/2017] [Accepted: 07/31/2017] [Indexed: 10/19/2022]
Abstract
Quantitative triplex real-time PCR (qPCR) offers an alternative method for detection of bacterial contamination. It provides quantitation of the number of gene copies. In our study, we established a qPCR assay to detect and quantify the specificity towards Bacillus cereus and B. thuringiensis. The assay was designed to detect a 280 bp fragment of motB gene encoding the flagellar motor protein, specific for detection of B. cereus and B. thuringiensis, excluding other group species B. pseudomycoides, B. mycoides and B. weihenstephanensis. Specificity of the assay was confirmed with 111 strains belonging to Bacillus cereus group and performed against 58 B. cereus, 50 B. thuringiensis, 3 other Bacillus bacteria and 9 non-Bacillus bacteria. Detection limit was determined for each assay. Direct analysis of samples revealed the specificity towards identification and characterization of B. cereus group cultured in nutrient media. Based on results, it was observed that motB showed 97% specificity towards B. cereus strains, 98% for B. thuringiensis but other B. cereus group showed less sensitivity (0%), thus, provides an efficient tool to identify B. cereus and B. thuringiensis. Further, environmental and food samples do not require band isolation, re-amplification or sequence identification. Thus, reducing the time and cost of analysis.
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Affiliation(s)
- Ramachandran Chelliah
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Shuai Wei
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Byung-Jae Park
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Se-Hun Kim
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Dong-Suk Park
- Department of Agricultural Biotechnology, National Academy of Agricultural Science, Rural Development Administration, Jeonju, 54874, Republic of Korea
| | - Soon Han Kim
- Food Microbiology Division, National Institute of Food and Drug Safety Evaluation, 187, Osongsaengmyeong 2-ro, Osong-eup, Heungdeok-gu, Cheongju-si, Chungcheongbuk-do, 28159, Republic of Korea
| | - Kim Seok Hwan
- Food Microbiology Division, National Institute of Food and Drug Safety Evaluation, 187, Osongsaengmyeong 2-ro, Osong-eup, Heungdeok-gu, Cheongju-si, Chungcheongbuk-do, 28159, Republic of Korea
| | - Deog-Hwan Oh
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, 24341, Republic of Korea.
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26
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Saleh-Lakha S, Leon-Velarde CG, Chen S, Lee S, Shannon K, Fabri M, Downing G, Keown B. A Study To Assess the Numbers and Prevalence of Bacillus cereus and Its Toxins in Pasteurized Fluid Milk. J Food Prot 2017; 80:1085-1089. [PMID: 28561637 DOI: 10.4315/0362-028x.jfp-16-521] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Bacillus cereus is a pathogenic adulterant of raw milk and can persist as spores and grow in pasteurized milk. The objective of this study was to determine the prevalence of B. cereus and its enterotoxins in pasteurized milk at its best-before date when stored at 4, 7, and 10°C. More than 5.5% of moderately temperature-abused products (stored at 7°C) were found to contain >105 CFU/mL B. cereus , and about 4% of them contained enterotoxins at a level that may result in foodborne illness; in addition, more than 31% of the products contained >105 CFU/mL B. cereus and associated enterotoxins when stored at 10°C. Results from a growth kinetic study demonstrated that enterotoxin production by B. cereus in pasteurized milk can occur in as short as 7 to 8 days of storage at 7°C. The higher B. cereus counts were associated with products containing higher butterfat content or with those produced using the conventional high-temperature, short-time pasteurization process. Traditional indicators, aerobic colony counts and psychrotrophic counts, were found to have no correlation with level of B. cereus in milk. The characterization of 17 representative B. cereus isolates from pasteurized milk revealed five toxigenic gene patterns, with all the strains carrying genes encoding for diarrheal toxins but not for an emetic toxin, and with one strain containing all four diarrheal enterotoxin genes (nheA, entFM, hblC, and cytK). The results of this study demonstrate the risks associated even with moderately temperature-abused pasteurized milk and the necessity of a controlled cold chain throughout the shelf life of fluid milk to enhance product safety and minimize foodborne illness.
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Affiliation(s)
- Saleema Saleh-Lakha
- 1 Laboratory Services Division, University of Guelph, Guelph, Ontario, Canada N1H 8J7
| | - Carlos G Leon-Velarde
- 1 Laboratory Services Division, University of Guelph, Guelph, Ontario, Canada N1H 8J7
| | - Shu Chen
- 1 Laboratory Services Division, University of Guelph, Guelph, Ontario, Canada N1H 8J7
| | - Susan Lee
- 1 Laboratory Services Division, University of Guelph, Guelph, Ontario, Canada N1H 8J7
| | - Kelly Shannon
- 1 Laboratory Services Division, University of Guelph, Guelph, Ontario, Canada N1H 8J7
| | - Martha Fabri
- 2 Food Safety Science Unit, Ontario Ministry of Agriculture, Food and Rural Affairs, 1 Stone Road West, Guelph, Ontario, Canada N1G 4Y2
| | - Gavin Downing
- 2 Food Safety Science Unit, Ontario Ministry of Agriculture, Food and Rural Affairs, 1 Stone Road West, Guelph, Ontario, Canada N1G 4Y2
| | - Bruce Keown
- 2 Food Safety Science Unit, Ontario Ministry of Agriculture, Food and Rural Affairs, 1 Stone Road West, Guelph, Ontario, Canada N1G 4Y2
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27
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Guérin A, Dargaignaratz C, Clavel T, Broussolle V, Nguyen-The C. Heat-resistance of psychrotolerant Bacillus cereus vegetative cells. Food Microbiol 2017; 64:195-201. [PMID: 28213026 DOI: 10.1016/j.fm.2017.01.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 01/17/2017] [Accepted: 01/19/2017] [Indexed: 12/31/2022]
Abstract
Spores of psychrotolerant strains of the foodborne pathogen Bacillus cereus can multiply during storage of cooked or pasteurized, refrigerated foods and can represent a risk if these cells are not eliminated during reheating of food product before consumption. We determined the heat-resistance of psychrotolerant B. cereus vegetative cells at different heating temperatures in laboratory medium and compared it with that of thermotolerant B. cereus vegetative cells. The z values, based on times for a 3 log10 reduction, of the vegetative cells of the three psychrotolerant phylogenetic groups of B. cereus varied between 3.02 °C and 4.84 °C. The temperature at which a 3 log10 reduction was achieved in 10 min varied between 47.6 °C and 49.2 °C for psychrotolerant vegetative cells and it was around 54.8 °C for thermotolerant vegetative cells. Moreover, 0.4 min at 60 °C would be sufficient for a 6 log10 CFU/ml reduction of the most heat resistant psychrotolerant B. cereus vegetative cells. These data clearly showed that psychrotolerant B. cereus vegetative cells can be rapidly eliminated by a mild heat treatment such as food reheating.
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Affiliation(s)
- Alizée Guérin
- UMR408 SQPOV « Sécurité et Qualité des Produits d'Origine Végétale », INRA, University of Avignon, 84000 Avignon, France
| | - Claire Dargaignaratz
- UMR408 SQPOV « Sécurité et Qualité des Produits d'Origine Végétale », INRA, University of Avignon, 84000 Avignon, France
| | - Thierry Clavel
- UMR408 SQPOV « Sécurité et Qualité des Produits d'Origine Végétale », INRA, University of Avignon, 84000 Avignon, France
| | - Véronique Broussolle
- UMR408 SQPOV « Sécurité et Qualité des Produits d'Origine Végétale », INRA, University of Avignon, 84000 Avignon, France
| | - Christophe Nguyen-The
- UMR408 SQPOV « Sécurité et Qualité des Produits d'Origine Végétale », INRA, University of Avignon, 84000 Avignon, France.
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Soudet S, Becquart C, Dezoteux F, Faure K, Staumont-Salle D, Delaporte E. Endocardite à Bacillus cereus avec probable porte d’entrée cutanée. Ann Dermatol Venereol 2017; 144:45-48. [DOI: 10.1016/j.annder.2016.09.045] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 05/14/2016] [Accepted: 09/14/2016] [Indexed: 11/26/2022]
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Li F, Zuo S, Yu P, Zhou B, Wang L, Liu C, Wei H, Hengyi Xu. Distribution and expression of the enterotoxin genes of Bacillus cereus in food products from Jiangxi Province, China. Food Control 2016. [DOI: 10.1016/j.foodcont.2016.02.049] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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30
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Forghani F, Wei S, Oh DH. A Rapid Multiplex Real-Time PCR High-Resolution Melt Curve Assay for the Simultaneous Detection of Bacillus cereus, Listeria monocytogenes, and Staphylococcus aureus in Food. J Food Prot 2016; 79:810-5. [PMID: 27296430 DOI: 10.4315/0362-028x.jfp-15-428] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Three important foodborne pathogens, Bacillus cereus, Listeria monocytogenes, and Staphylococcus aureus, are of great concern for food safety. They may also coexist in food matrices and, in the case of B. cereus and S. aureus, the resulting illnesses can resemble each other owing to similar symptoms. Therefore, their simultaneous detection may have advantages in terms of cost savings and rapidity. Given this context, a rapid multiplex real-time PCR high-resolution melt curve assay for the simultaneous detection of these three pathogens in food was developed. The assay successfully detected B. cereus (gyrB), L. monocytogenes (hly), and S. aureus (nuc) in a single reaction, and the average melting temperatures were 76.23, 80.19, and 74.01°C, respectively. The application of SYTO9 dye and a slow melt curve analysis ramp rate (0.1°C/s) enabled the production of sharp, high-resolution melt curve peaks that were easily distinguishable from each other. The detection limit in food (milk, rice, and lettuce) was 3.7 × 10(3) CFU/g without an enrichment step and 3.7 × 10(1) CFU/g following the 10-h enrichment. Hence, the assay developed here is specific and sensitive, providing an efficient tool for implementation in food for the simultaneous detection of B. cereus, L. monocytogenes, and S. aureus .
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Affiliation(s)
- Fereidoun Forghani
- Department of Bioconvergence Science and Technology, College of Agriculture and Life Sciences, Kangwon National University, Chuncheon, Gangwon 200-701, Republic of Korea; Department of Microbiology, Immunology and Biochemistry, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Shuai Wei
- Department of Bioconvergence Science and Technology, College of Agriculture and Life Sciences, Kangwon National University, Chuncheon, Gangwon 200-701, Republic of Korea
| | - Deog-Hwan Oh
- Department of Bioconvergence Science and Technology, College of Agriculture and Life Sciences, Kangwon National University, Chuncheon, Gangwon 200-701, Republic of Korea.
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Cui Y, Liu X, Dietrich R, Märtlbauer E, Cao J, Ding S, Zhu K. Characterization ofBacillus cereusisolates from local dairy farms in China. FEMS Microbiol Lett 2016; 363:fnw096. [DOI: 10.1093/femsle/fnw096] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2016] [Indexed: 12/11/2022] Open
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Park KM, Kim HJ, Jeong MC, Koo M. Occurrence of Toxigenic Bacillus cereus and Bacillus thuringiensis in Doenjang, a Korean Fermented Soybean Paste. J Food Prot 2016; 79:605-12. [PMID: 27052865 DOI: 10.4315/0362-028x.jfp-15-416] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
This study determined the prevalence and toxin profile of Bacillus cereus and Bacillus thuringiensis in doenjang, a fermented soybean food, made using both traditional and commercial methods. The 51 doenjang samples tested were broadly contaminated with B. cereus; in contrast, only one sample was positive for B. thuringiensis. All B. cereus isolates from doenjang were positive for diarrheal toxin genes. The frequencies of nheABC and hblACD in traditional samples were 22.7 and 0%, respectively, whereas 5.1 and 5.1% of B. cereus isolates from commercial samples possessed nheABC and hblACD, respectively. The detection rate of ces gene was 10.8%. The predominant toxin profile among isolates from enterotoxigenic B. cereus in doenjang was profile 4 (entFM-bceT-cytK). The major enterotoxin genes in emetic B. cereus were cytK, entFM, and nheA genes. The B. thuringiensis isolate was of the diarrheagenic type. These results provide a better understanding of the epidemiology of the enterotoxigenic and emetic B. cereus groups in Korean fermented soybean products.
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Affiliation(s)
- Kyung Min Park
- Department of Food Biotechnology, Korea University of Science & Technology, Daejoen 305-333, South Korea, Department of Food Storage and Distribution System, Korea Food Research Institute, Gyeonggi 463-746, South Korea
| | - Hyun Jung Kim
- Department of Food Biotechnology, Korea University of Science & Technology, Daejoen 305-333, South Korea, Department of Food Safety, Korea Food Research Institute, Gyeonggi 463-746, South Korea
| | - Moon Cheol Jeong
- Department of Food Storage and Distribution System, Korea Food Research Institute, Gyeonggi 463-746, South Korea
| | - Minseon Koo
- Department of Food Biotechnology, Korea University of Science & Technology, Daejoen 305-333, South Korea, Department of Food Storage and Distribution System, Korea Food Research Institute, Gyeonggi 463-746, South Korea.
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A novel pentaplex real time (RT)- PCR high resolution melt curve assay for simultaneous detection of emetic and enterotoxin producing Bacillus cereus in food. Food Control 2016. [DOI: 10.1016/j.foodcont.2015.08.030] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Rapid detection of viable Bacillus cereus emetic and enterotoxic strains in food by coupling propidium monoazide and multiplex PCR (PMA-mPCR). Food Control 2015. [DOI: 10.1016/j.foodcont.2015.02.049] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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35
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Isolation of Bacillus cereus Group from the Fecal Material of Endangered Wood Turtles. Curr Microbiol 2015; 71:524-7. [PMID: 26175111 DOI: 10.1007/s00284-015-0875-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 06/17/2015] [Indexed: 10/23/2022]
Abstract
Members of the Bacillus cereus group are opportunistic human pathogens. They can be found in a broad range of foods. Diarrheal food poisoning and/or emetic type syndromes can result from eating contaminated food. In this study, seven B. cereus group members were isolated from the fecal material of Wood Turtles (Glyptemys insculpta). The isolates were then assessed for the presence of enterotoxin genes (nheA, entFM, hblC, and cytK) using PCR. The most prevalent is the nonhemolytic enterotoxin gene which was found in all seven isolates.
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Ehling-Schulz M, Frenzel E, Gohar M. Food-bacteria interplay: pathometabolism of emetic Bacillus cereus. Front Microbiol 2015; 6:704. [PMID: 26236290 PMCID: PMC4500953 DOI: 10.3389/fmicb.2015.00704] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Accepted: 06/26/2015] [Indexed: 11/25/2022] Open
Abstract
Bacillus cereus is a Gram-positive endospore forming bacterium known for its wide spectrum of phenotypic traits, enabling it to occupy diverse ecological niches. Although the population structure of B. cereus is highly dynamic and rather panmictic, production of the emetic B. cereus toxin cereulide is restricted to strains with specific genotypic traits, associated with distinct environmental habitats. Cereulide is an ionophoric dodecadepsipeptide that is produced non-ribosomally by an enzyme complex with an unusual modular structure, named cereulide synthetase (Ces non-ribosomal peptide synthetase). The ces gene locus is encoded on a mega virulence plasmid related to the B. anthracis toxin plasmid pXO1. Cereulide, a highly thermo- and pH- resistant molecule, is preformed in food, evokes vomiting a few hours after ingestion, and was shown to be the direct cause of gastroenteritis symptoms; occasionally it is implicated in severe clinical manifestations including acute liver failures. Control of toxin gene expression in emetic B. cereus involves central transcriptional regulators, such as CodY and AbrB, thereby inextricably linking toxin gene expression to life cycle phases and specific conditions, such as the nutrient supply encountered in food matrices. While in recent years considerable progress has been made in the molecular and biochemical characterization of cereulide toxin synthesis, far less is known about the embedment of toxin synthesis in the life cycle of B. cereus. Information about signals acting on toxin production in the food environment is lacking. We summarize the data available on the complex regulatory network controlling cereulide toxin synthesis, discuss the role of intrinsic and extrinsic factors acting on toxin biosynthesis in emetic B. cereus and stress how unraveling these processes can lead to the development of novel effective strategies to prevent toxin synthesis in the food production and processing chain.
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Affiliation(s)
- Monika Ehling-Schulz
- Functional Microbiology, Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine ViennaVienna, Austria
| | - Elrike Frenzel
- Functional Microbiology, Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine ViennaVienna, Austria
| | - Michel Gohar
- INRA, UMR1319 Micalis, AgroParistech – Domaine de Vilvert, Génétique Microbienne et EnvironnementJouy-en-Josas, France
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