Multi-locus sequence typing and virulence profile in <em>Bacillus cereus sensu</em> lato strains isolated from dairy products

Members of Bacillus cereus group are important food contaminants and they are of relevant interest in food safety and public heath due to their ability to cause two distinct forms of food poisoning, emetic and diarrhoeal syndrome. In the present study, 90 strains of B. cereus isolated from dairy products, have been typed using Multilocus Sequence Typing (MLST) analysis and investigated for the occurrence of 10 enterotoxigenic genes (hblA, hblC, hblD, nheA, nheB, nheC, cytK, entFM, entS and bceT) and one emetogenic gene (ces), to determine their genetic diversity. A total of 58 sequence types were identified and among these 17 were signalled as new profiles. Among the virulence genes, the majority of our strains carried the entS (92%), entFM (86%), nhe (82%) and cytK (72%) genes. All remaining genes were identified in at least one strain with different prevalence, stressing the genetic diversity, how even the different grade of pathogenicity of B. cereus isolated from dairy products.

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Discrimination of Psychrotrophic and Mesophilic Strains of the Bacillus cereus Group by PCR Targeting of Major Cold Shock Protein Genes

Applied and Environmental Microbiology ◽

10.1128/aem.64.9.3525-3529.1998 ◽

1998 ◽

Vol 64 (9) ◽

pp. 3525-3529 ◽

Cited By ~ 83

Author(s):

Kevin P. Francis ◽

Ralf Mayr ◽

Felix von Stetten ◽

Gordon S. A. B. Stewart ◽

Siegfried Scherer

Keyword(s):

Bacillus Cereus ◽

Dairy Products ◽

Cold Shock ◽

Food Poisoning ◽

Cold Shock Protein ◽

Pcr Assay ◽

Specific Primers ◽

Bacillus Cereus Group ◽

Cold Adapted ◽

Pcr Targeting

ABSTRACT Detection of psychrotrophic strains (those able to grow at or below 7°C) of the Bacillus cereus group (Bacillus cereus, Bacillus thuringiensis, and Bacillus mycoides) in food products is at present extremely slow with conventional microbiology. This is due to an inability to discriminate these cold-adapted strains from their mesophilic counterparts (those able to grow only above 7°C) by means other than growth at low temperature, which takes 5 to 10 days for detection. Here we report the development of a single PCR assay that, using major cold shock protein-specific primers and appropriate annealing temperatures, is capable of both rapidly identifying bacteria of the B. cereus group and discriminating between psychrotrophic and mesophilic strains. It is intended that this development help to more accurately predict the shelf life of refrigerated pasteurized food and dairy products and to reduce the incidence of food poisoning by psychrotrophic strains of the B. cereus group.

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Exposure to Bacillus cereus in Water Buffalo Mozzarella Cheese

Foods ◽

10.3390/foods9121899 ◽

2020 ◽

Vol 9 (12) ◽

pp. 1899

Author(s):

Angela Michela Immacolata Montone ◽

Federico Capuano ◽

Andrea Mancusi ◽

Orlandina Di Maro ◽

Maria Francesca Peruzy ◽

...

Keyword(s):

Bacillus Cereus ◽

Dairy Products ◽

Water Buffalo ◽

Diarrheal Disease ◽

Food Poisoning ◽

Mozzarella Cheese ◽

Food Borne ◽

Genes Encoding ◽

Spoilage Bacterium ◽

Hemolysin Bl

Bacillus cereus is a spoilage bacterium and is recognized as an agent of food poisoning. Two food-borne illnesses are caused by B. cereus: a diarrheal disease, associated with cytotoxin K, hemolysin BL, non-hemolytic enterotoxin and enterotoxin FM, and an emetic syndrome, associated with the cereulide toxin. Owing to the heat resistance of B. cereus and its ability to grow in milk, this organism should be considered potentially hazardous in dairy products. The present study assessed the risk of B. cereus poisoning due to the consumption of water buffalo mozzarella cheese. A total of 340 samples were analyzed to determine B. cereus counts (ISO 7932:2005); isolates underwent molecular characterization to detect the presence of genes encoding toxins. Eighty-nine (26.1%) samples harbored B. cereus strains, with values ranging from 2.2 × 102 to 2.6 × 106 CFU/g. Isolates showed eight different molecular profiles, and some displayed virulence characteristics. Bacterial counts and the toxin profiles of isolates were evaluated both separately and jointly to assess the risk of enteritis due to B. cereus following the consumption of buffalo mozzarella cheese. In conclusion, the results of the present study showed that the risk of poisoning by B. cereus following the consumption of this cheese was moderate.

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The Genetically Remote Pathogenic Strain NVH391-98 of the Bacillus cereus Group Is Representative of a Cluster of Thermophilic Strains

Applied and Environmental Microbiology ◽

10.1128/aem.02242-07 ◽

2007 ◽

Vol 74 (4) ◽

pp. 1276-1280 ◽

Cited By ~ 32

Author(s):

Sandrine Auger ◽

Nathalie Galleron ◽

Elena Bidnenko ◽

S. Dusko Ehrlich ◽

Alla Lapidus ◽

...

Keyword(s):

Bacillus Cereus ◽

Food Poisoning ◽

Temperate Phage ◽

Pathogenic Strain ◽

Bacillus Cereus Group ◽

Close Relatives

ABSTRACT Bacteria of the Bacillus cereus group are known to cause food poisoning. A rare phylogenetically remote strain, NVH391-98, was recently characterized to encode a particularly efficient cytotoxin K presumably responsible for food poisoning. This pathogenic strain and its close relatives can be phenotypically distinguished from other strains of the B. cereus group by the inability to grow at temperatures below 17°C and by the ability to grow at temperatures from 48 to 53°C. A temperate phage, phBC391A2, residing in the genome of NVH391-98 allows us to distinguish the three known members of this thermophilic strain cluster.

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Analysis of enterotoxin production by Bacillus cereus from dairy products, food poisoning incidents and non-gastrointestinal infections

International Journal of Food Microbiology ◽

10.1016/0168-1605(93)90197-o ◽

1993 ◽

Vol 17 (4) ◽

pp. 269-279 ◽

Cited By ~ 90

Author(s):

Per Einar Granum ◽

Sigrid Brynestad ◽

John M. Kramer

Keyword(s):

Bacillus Cereus ◽

Dairy Products ◽

Food Poisoning ◽

Gastrointestinal Infections ◽

Enterotoxin Production

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Characterization of Bacillus cereus in Dairy Products in China

Toxins ◽

10.3390/toxins12070454 ◽

2020 ◽

Vol 12 (7) ◽

pp. 454 ◽

Cited By ~ 1

Author(s):

Xiao-Ye Liu ◽

Qiao Hu ◽

Fei Xu ◽

Shuang-Yang Ding ◽

Kui Zhu

Keyword(s):

Bacillus Cereus ◽

Virulence Factors ◽

Prevalence Rate ◽

Dairy Products ◽

Foodborne Pathogen ◽

Food Poisoning ◽

Intervention Strategies ◽

Epidemiological Characteristics ◽

Shed Light

Bacillus cereus is a common and ubiquitous foodborne pathogen with an increasing prevalence rate in dairy products in China. High and unmet demands for such products, particularly milk, raise the risk of B. cereus associated contamination. The presence of B. cereus and its virulence factors in dairy products may cause food poisoning and other illnesses. Thus, this review first summarizes the epidemiological characteristics and analytical assays of B. cereus from dairy products in China, providing insights into the implementation of intervention strategies. In addition, the recent achievements on the cytotoxicity and mechanisms of B. cereus are also presented to shed light on the therapeutic options for B. cereus associated infections.

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Identification of Bacillus cereus Group Species Associated with Food Poisoning Outbreaks in British Columbia, Canada

Applied and Environmental Microbiology ◽

10.1128/aem.01284-08 ◽

2008 ◽

Vol 74 (23) ◽

pp. 7451-7453 ◽

Cited By ~ 49

Author(s):

Lorraine McIntyre ◽

Kathryn Bernard ◽

Daniel Beniac ◽

Judith L. Isaac-Renton ◽

David Craig Naseby

Keyword(s):

British Columbia ◽

Bacillus Cereus ◽

Food Poisoning ◽

Bacillus Cereus Group ◽

Group Species

ABSTRACT Food poisoning laboratories identify Bacillus cereus using routine methods that may not differentiate all Bacillus cereus group species. We recharacterized Bacillus food-poisoning strains from 39 outbreaks and identified B. cereus in 23 outbreaks, B. thuringiensis in 4, B. mycoides in 1, and mixed strains of Bacillus in 11 outbreaks.

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Prevalence and Genetic Diversity of C. Jejuni Isolated from Broilers and their Environment Using flaA-RFLP Typing and MLST Analysis

Annals of Animal Science ◽

10.2478/aoas-2020-0008 ◽

2020 ◽

Vol 20 (2) ◽

pp. 485-501

Author(s):

Viktorija Lėgaudaitė Lydekaitienė ◽

E. Kudirkienė

Keyword(s):

Genetic Diversity ◽

Restriction Fragment Length Polymorphism ◽

Campylobacter Jejuni ◽

Length Polymorphism ◽

Fragment Length Polymorphism ◽

Wild Birds ◽

Mlst Analysis ◽

Sequence Types ◽

Restriction Fragment Length ◽

Rflp Typing

AbstractCampylobacter is highly diverse genetically and also undergoes frequent intraspecific recombination. A major source of campylobacteriosis, which is transmitted to humans is found in poultry. The assessment of the genetic diversity among Campylobacter population is critical to our understanding of the epidemiology. The genetic diversity of Campylobacter jejuni isolates in broilers and their environment were investigated by flaA-restriction fragment length polymorphism (RFLP) and multilocus sequence typing (MLST). The study revealed that 92.3% of the examined broiler flocks were contaminated with Campylobacter spp. A total number of 35 different flaA types defined by flaA-RFLP were found in 448 C. jejuni isolates originated from broilers, litter, puddles, zones, anteroom and wild birds. The most dominant flaA type was XXV. MLST defined 20 sequence types (STs) belonging to 10 clonal complexes (CCs). Among all the STs 9 isolates (15%) were consigned to 2 different STs (ST-7413 and ST-4800), which could not be assigned. The most common CCs were ST-21 and ST-179. The ST-21 CC was common in broilers and environment (puddle water and concentric zones) and the ST-179 CC was specific to wild birds, but also was found in puddle water and concentric zones.

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Application of Bacillus thuringiensis strains with conjugal and mobilizing capability drives gene transmissibility within Bacillus cereus group populations in confined habitats

BMC Microbiology ◽

10.1186/s12866-020-02047-4 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Xiaomin Hu ◽

Doudou Huang ◽

Joseph Ogalo ◽

Peiling Geng ◽

Zhiming Yuan ◽

...

Keyword(s):

Bacillus Thuringiensis ◽

Bacillus Cereus ◽

Conjugative Plasmid ◽

Occurrence Rate ◽

Mixed Mating ◽

Wide Spread ◽

Bacillus Cereus Group ◽

Physiological And Biochemical Characteristics ◽

Sequence Types ◽

Physiological And Biochemical

Abstract Background Bacillus thuringiensis bacteria share similar genetic, physiological, and biochemical characteristics with other members of the Bacillus cereus group. Their diversity and entomopathogenic origin are related to their mobile genetic elements. However, the effects of wide-spread application of B. thuringiensis-based pesticides on genetically related B. cereus group populations present in the environment remain poorly understood. Results We first identified pBMB76 from B. thuringiensis tenebrionis as a new conjugative plasmid. Mixed mating experiments suggested that pBMB76 may compete with pHT73, another known conjugative plasmid. Applications of single (tenebrionis 4AA1 and kurstaki HD73 carrying pBMB76 and pHT73, respectively) and mixed (4AA1 + HD73) B. thuringiensis strains were performed in confined plot habitats (soil and leaf) over two planting seasons. In total, 684 B. cereus group isolates were randomly selected from different treatment sets, and the transmissibility and occurrence rate of potential conjugative plasmids were surveyed. Results showed that the percentage of isolates with plasmid mobility was markedly enhanced in the B. thuringiensis-sprayed groups. Furthermore, we performed multi-locus sequence typing (MLST) for a subset of 291 isolates, which indicated that the dominant sequence types in the treated habitats were identical or related to the corresponding sprayed formulations. Conclusions The application of B. thuringiensis strains with conjugal and mobilizing capability drove gene transmissibility within the B. cereus group populations in confined habitats and potentially modified the population structure.

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