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Sample records for cereus group represents

  1. The Genetically Remote Pathogenic Strain NVH391-98 of the Bacillus cereus Group Represents the Cluster of Thermophilic Strains

    Energy Technology Data Exchange (ETDEWEB)

    Auger, Sandrine; Galleron, Nathalie; Bidnenko, Elena; Ehrlich, S. Dusko; Lapidus, Alla; Sorokin, Alexei

    2007-10-02

    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 degrees C and by the ability to grow at temperatures from 48 to 53 degrees 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.

  2. Comparative genome analysis of Bacillus cereus group genomes with Bacillus subtilis

    OpenAIRE

    Anderson, Iain; Sorokin, Alexei; Kapatral, Vinayak; Reznik, Gary; Bhattacharya, Anamitra; Mikhailova, Natalia; Burd, Henry; Joukov, Victor; Kaznadzey, Denis; Walunas, Theresa; D'Souza, Mark; Larsen, Niels; Pusch, Gordon; Liolios, Konstantinos; Grechkin, Yuri

    2005-01-01

    Genome features of the Bacillus cereus group genomes (representative strains of Bacillus cereus, Bacillus anthracis and Bacillus thuringiensis sub spp israelensis) were analyzed and compared with the Bacillus subtilis genome. A core set of 1,381 protein families among the four Bacillus genomes, with an additional set of 933 families common to the B. cereus group, was identified. Differences in signal transduction pathways, membrane transporters, cell surface structures, cell wall, and S-...

  3. Antimicrobial resistance among Pseudomonas spp. and the Bacillus cereus group isolated from Danish agricultural soil

    DEFF Research Database (Denmark)

    Jensen, Lars Bogø; Baloda, S.; Boye, Mette; Aarestrup, Frank Møller

    From four Danish pig farms, bacteria of Pseudomonas spp. and the Bacillus cereus group were isolated from soil and susceptibility towards selected antimicrobials was tested. From each farm, soil samples representing soil just before and after spread of animal waste and undisturbed agricultural soil......, when possible, were collected. Soil from a well-characterized Danish farm soil (Hojbakkegaard) was collected for comparison. The Psudomonas spp. and B. cereus were chosen as representative for Gram-negative and Gram-positive indigenous soil bacteria to test the effect of spread of animal waste on...... spp., and for bacitracin, erythromycin, penicillin and streptomycin for the B. cereus group. Variations in resistance levels were observed when soil before and after spread of animal waste was compared, indicating an effect from spread of animal waste....

  4. Comparative genome analysis of Bacillus cereus group genomes withBacillus subtilis

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Iain; Sorokin, Alexei; Kapatral, Vinayak; Reznik, Gary; Bhattacharya, Anamitra; Mikhailova, Natalia; Burd, Henry; Joukov, Victor; Kaznadzey, Denis; Walunas, Theresa; D' Souza, Mark; Larsen, Niels; Pusch,Gordon; Liolios, Konstantinos; Grechkin, Yuri; Lapidus, Alla; Goltsman,Eugene; Chu, Lien; Fonstein, Michael; Ehrlich, S. Dusko; Overbeek, Ross; Kyrpides, Nikos; Ivanova, Natalia

    2005-09-14

    Genome features of the Bacillus cereus group genomes (representative strains of Bacillus cereus, Bacillus anthracis and Bacillus thuringiensis sub spp israelensis) were analyzed and compared with the Bacillus subtilis genome. A core set of 1,381 protein families among the four Bacillus genomes, with an additional set of 933 families common to the B. cereus group, was identified. Differences in signal transduction pathways, membrane transporters, cell surface structures, cell wall, and S-layer proteins suggesting differences in their phenotype were identified. The B. cereus group has signal transduction systems including a tyrosine kinase related to two-component system histidine kinases from B. subtilis. A model for regulation of the stress responsive sigma factor sigmaB in the B. cereus group different from the well studied regulation in B. subtilis has been proposed. Despite a high degree of chromosomal synteny among these genomes, significant differences in cell wall and spore coat proteins that contribute to the survival and adaptation in specific hosts has been identified.

  5. Complete Genome Sequences of Nine Bacillus cereus Group Phages

    Science.gov (United States)

    Foltz, Samantha

    2016-01-01

    We report the sequences of nine novel Bacillus cereus group bacteriophages: DIGNKC, Juglone, Nemo, Nigalana, NotTheCreek, Phrodo, SageFayge, Vinny, and Zuko. These bacteriophages are double-stranded DNA-containing Myoviridae isolated from soil samples using B. thuringiensis subsp. kurstaki as the host bacterium. PMID:27417827

  6. Polymerase chain reaction assay for the detection of Bacillus cereus group cells

    DEFF Research Database (Denmark)

    Hansen, Bjarne Munk; Leser, Thomas D.; Hendriksen, Niels Bohse

    2001-01-01

    Recent investigations have shown that members of the Bacillus cereus group carry genes which have the potential to cause gastrointestinal and somatic diseases. Although most cases of diseases caused by the B. cereus group bacteria are relatively mild, it is desirable to be able to detect members of...... the B. cereus group in food and in the environment. Using 16S rDNA as target, a PCR assay for the detection of B. cereus group cells has been developed. Primers specific for the 16S rDNA of the B. cereus group bacteria were selected and used in combination with consensus primers for 165 rDNA as...... internal PCR procedure control. The PCR procedure was optimized with respect to annealing temperature. When DNA from the B. cereus group bacteria was present, the PCR assay yielded a B. cereus specific fragment, while when non-B. cereus prokaryotic DNA was present, the consensus 165 rDNA primers directed...

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

    OpenAIRE

    McIntyre, Lorraine; Bernard, Kathryn; Beniac, Daniel; Isaac-Renton, Judith L.; Naseby, David Craig

    2008-01-01

    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.

  8. Extending the cereus group genomics to putative food-bornepathogens of different toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Lapidus, Alla; Goltsman, Eugene; Auger, Sandrine; Galleron,Nathalie; Segurens, Beatrice; Dossat, Carole; Land, Miriam L.; Broussole,Veronique; Brillard, Julien; Guinebretiere, Marie-Helene; Sanchis,Vincent; Nguen-the, Christophe; Lereclus, Didier; Richardson, Paul; Winker, Patrick; Weissenbach, Jean; Ehrlich, S.Dusko; Sorokin, Alexei

    2006-08-24

    The cereus group represents sporulating soil bacteriacontaining pathogenic strains which may cause diarrheic or emetic foodpoisoning outbreaks. Multiple locus sequence typing revealed a presencein natural samples of these bacteria of about thirty clonal complexes.Application of genomic methods to this group was however biased due tothe major interest for representatives closely related to B. anthracis.Albeit the most important food-borne pathogens were not yet defined,existing dataindicate that they are scattered all over the phylogenetictree. The preliminary analysis of the sequences of three genomesdiscussed in this paper narrows down the gaps in our knowledge of thecereus group. The strain NVH391-98 is a rare but particularly severefood-borne pathogen. Sequencing revealed that the strain must be arepresentative of a novel bacterial species, for which the name Bacilluscytotoxis is proposed. This strain has a reduced genome size compared toother cereus group strains. Genome analysis revealed absence of sigma Bfactor and the presence of genes encoding diarrheic Nhe toxin, notdetected earlier. The strain B. cereus F837/76 represents a clonalcomplex close to that of B. anthracis. Including F837/76, three such B.cereus strains had been sequenced. Alignment of genomes suggests that B.anthracis is their common ancestor. Since such strains often emerge fromclinical cases, they merit a special attention. The third strain, KBAB4,is a typical psychrotrophe characteristic to unbiased soil communities.Phylogenic studies show that in nature it is the most active group interms of gene exchange. Genomic sequence revealed high presence ofextra-chromosomal genetic material (about 530 kb) that may account forthis phenomenon. Genes coding Nhe-like toxin were found on a big plasmidin this strain. This may indicate a potential mechanism of toxicityspread from the psychrotrophic strain community. The results of thisgenomic work and ecological compartments of different strains incite

  9. Antimicrobial resistance among Pseudomonas spp. and the Bacillus cereus group isolated from Danish agricultural soil

    DEFF Research Database (Denmark)

    Jensen, Lars Bogø; Baloda, S.; Boye, Mette;

    2001-01-01

    , when possible, were collected. Soil from a well-characterized Danish farm soil (Hojbakkegaard) was collected for comparison. The Psudomonas spp. and B. cereus were chosen as representative for Gram-negative and Gram-positive indigenous soil bacteria to test the effect of spread of animal waste on...... selection of resistance among soil bacteria. No variations in resistance levels were observed between farms; but when the four differently treated soils were compared, resistance was seen for carbadox, chloramphenicol, nalidixan (nalidixic acid), nitrofurantoin, streptomycin and tetracycline for Pseudomonas...... spp., and for bacitracin, erythromycin, penicillin and streptomycin for the B. cereus group. Variations in resistance levels were observed when soil before and after spread of animal waste was compared, indicating an effect from spread of animal waste....

  10. Complete Genome Sequence of Bacillus cereus Group Phage TsarBomba

    OpenAIRE

    Erill, Ivan; Caruso, Steven M.

    2015-01-01

    The Bacillus cereus group bacteriophage TsarBomba, a double-stranded DNA Myoviridae, was isolated from soil collected in Saratov, Russia. TsarBomba was found to be similar to Bacillus phages BCP78 and BCU4, and to have a wide host range among Bacillus cereus group species.

  11. Characterization and comparative genomic analysis of bacteriophages infecting members of the Bacillus cereus group.

    Science.gov (United States)

    Lee, Ju-Hoon; Shin, Hakdong; Ryu, Sangryeol

    2014-05-01

    The Bacillus cereus group phages infecting B. cereus, B. anthracis, and B. thuringiensis (Bt) have been studied at the molecular level and, recently, at the genomic level to control the pathogens B. cereus and B. anthracis and to prevent phage contamination of the natural insect pesticide Bt. A comparative phylogenetic analysis has revealed three different major phage groups with different morphologies (Myoviridae for group I, Siphoviridae for group II, and Tectiviridae for group III), genome size (group I > group II > group III), and lifestyle (virulent for group I and temperate for group II and III). A subsequent phage genome comparison using a dot plot analysis showed that phages in each group are highly homologous, substantiating the grouping of B. cereus phages. Endolysin is a host lysis protein that contains two conserved domains: a cell-wall-binding domain (CBD) and an enzymatic activity domain (EAD). In B. cereus sensu lato phage group I, four different endolysin groups have been detected, according to combinations of two types of CBD and four types of EAD. Group I phages have two copies of tail lysins and one copy of endolysin, but the functions of the tail lysins are still unknown. In the B. cereus sensu lato phage group II, the B. anthracis phages have been studied and applied for typing and rapid detection of pathogenic host strains. In the B. cereus sensu lato phage group III, the B. thuringiensis phages Bam35 and GIL01 have been studied to understand phage entry and lytic switch regulation mechanisms. In this review, we suggest that further study of the B. cereus group phages would be useful for various phage applications, such as biocontrol, typing, and rapid detection of the pathogens B. cereus and B. anthracis and for the prevention of phage contamination of the natural insect pesticide Bt. PMID:24264384

  12. The possibility of discriminating within the Bacillus cereus group using gyrB sequencing and PCR-RFLP

    DEFF Research Database (Denmark)

    Jensen, Gert B; Fisker, Niels; Sparsø, Thomas;

    2005-01-01

    Based on a combination of PCR and restriction endonuclease (RE) digestion (PCR-RE digestion), we have examined the possibility of differentiating members of the Bacillus cereus group. Fragments of the gyrB gene (362 bp) from pure cultures of 12 B. cereus, 25 B. thuringiensis, 25 B. mycoides and two......, it was not possible to discriminate between the B. cereus and the B. thuringiensis strains using the methods described....

  13. A Randomly Amplified Polymorphic DNA Marker Specific for the Bacillus cereus Group Is Diagnostic for Bacillus anthracis

    OpenAIRE

    Daffonchio, Daniele; Borin, Sara; Frova, Giuseppe; Gallo, Romina; Mori, Elena; Fani, Renato; Sorlini, Claudia

    1999-01-01

    Aiming to develop a DNA marker specific for Bacillus anthracis and able to discriminate this species from Bacillus cereus, Bacillus thuringiensis, and Bacillus mycoides, we applied the randomly amplified polymorphic DNA (RAPD) fingerprinting technique to a collection of 101 strains of the genus Bacillus, including 61 strains of the B. cereus group. An 838-bp RAPD marker (SG-850) specific for B. cereus, B. thuringiensis, B. anthracis, and B. mycoides was identified. This fragment included a pu...

  14. Peptidoglycan from Bacillus cereus Mediates Commensalism with Rhizosphere Bacteria from the Cytophaga-Flavobacterium Group

    OpenAIRE

    Peterson, Snow Brook; Dunn, Anne K.; Klimowicz, Amy K.; Handelsman, Jo

    2006-01-01

    Previous research in our laboratory revealed that the introduction of Bacillus cereus UW85 can increase the populations of bacteria from the Cytophaga-Flavobacterium (CF) group of the Bacteroidetes phylum in the soybean rhizosphere, suggesting that these rhizosphere microorganisms have a beneficial relationship (G. S. Gilbert, J. L. Parke, M. K. Clayton, and J. Handelsman, Ecology 74:840-854, 1993). In the present study, we determined the frequency at which CF bacteria coisolated with B. cere...

  15. Description of Bacillus toyonensis sp. nov., a novel species of the Bacillus cereus group, and pairwise genome comparisons of the species of the group by means of ANI calculations.

    Science.gov (United States)

    Jiménez, Guillermo; Urdiain, Mercedes; Cifuentes, Ana; López-López, Aránzazu; Blanch, Anicet R; Tamames, Javier; Kämpfer, Peter; Kolstø, Anne-Brit; Ramón, Daniel; Martínez, Juan F; Codoñer, Francisco M; Rosselló-Móra, Ramon

    2013-09-01

    Strain BCT-7112(T) was isolated in 1966 in Japan from a survey designed to obtain naturally occurring microorganisms as pure cultures in the laboratory for use as probiotics in animal nutrition. This strain, which was primarily identified as Bacillus cereus var toyoi, has been in use for more than 30 years as the active ingredient of the preparation TOYOCERIN(®), an additive for use in animal nutrition (e.g. swine, poultry, cattle, rabbits and aquaculture). Despite the fact that the strain was initially classified as B. cereus, it showed significant genomic differences from the type strains of the B. cereus group that were large enough (ANI values below 92%) to allow it to be considered as a different species within the group. The polyphasic taxonomic study presented here provides sufficient discriminative parameters to classify BCT-7112(T) as a new species for which the name Bacillus toyonensis sp. nov. is proposed, with BCT-7112(T) (=CECT 876(T); =NCIMB 14858(T)) being designated as the type strain. In addition, a pairwise comparison between the available genomes of the whole B. cereus group by means of average nucleotide identity (ANI) calculations indicated that besides the eight classified species (including B. toyonensis), additional genomospecies could be detected, and most of them also had ANI values below 94%. ANI values were on the borderline of a species definition only in the cases of representatives of B. cereus versus B. thuringiensis, and B. mycoides and B. weihenstephanensis. PMID:23791203

  16. Toxigenic genes, spoilage potential, and antimicrobial resistance of Bacillus cereus group strains from ice cream.

    Science.gov (United States)

    Arslan, Seza; Eyi, Ayla; Küçüksarı, Rümeysa

    2014-02-01

    Bacillus spp. can be recovered from almost every environment. It is also found readily in foods, where it may cause food spoilage and/or food poisoning due to its toxigenic and pathogenic nature, and extracellular enzymes. In this study, 29 Bacillus cereus group strains from ice cream were examined for the presence of following virulence genes hblC, nheA, cytK and ces genes, and tested for a range of the extracellular enzymes, and antimicrobial susceptibility. The strains were found to produce extracellular enzymes: proteolytic and lipolytic activity, gelatin hydrolysis and lecithinase production (100%), DNase production (93.1%) and amylase activity (93.1%). Of 29 strains examined, 24 (82.8%) showed hemolytic activity on blood agar. Beta-lactamase enzyme was only produced by 20.7% of B. cereus group. Among 29 B. cereus group from ice cream, nheA was the most common virulence gene detected in 44.8% of the strains, followed by hblC gene with 17.2%. Four (13.8%) of the 29 strains were positive for both hblC gene and nheA gene. Contrarily, cytK and ces genes were not detected in any of the strains. Antimicrobial susceptibility of ice cream isolates was tested to 14 different antimicrobial agents using the disc diffusion method. We detected resistance to penicillin and ampicillin with the same rate of 89.7%. Thirty-one percent of the strains were multiresistant to three or more antibiotics. This study emphasizes that the presence of natural isolates of Bacillus spp. harboring one or more enterotoxin genes, producing extracellular enzymes which may cause spoilage and acquiring antibiotic resistance might hold crucial importance in the food safety and quality. PMID:24309214

  17. Conducting polymer based DNA biosensor for the detection of the Bacillus cereus group species

    Science.gov (United States)

    Velusamy, Vijayalakshmi; Arshak, Khalil; Korostynska, Olga; Oliwa, Kamila; Adley, Catherine

    2009-05-01

    Biosensor designs are emerging at a significant rate and play an increasingly important role in foodborne pathogen detection. Conducting polymers are excellent tools for the fabrication of biosensors and polypyrrole has been used in the detection of biomolecules due to its unique properties. The prime intention of this paper was to pioneer the design and fabrication of a single-strand (ss) DNA biosensor for the detection of the Bacillus cereus (B.cereus) group species. Growth of B. cereus, results in production of several highly active toxins. Therefore, consumption of food containing >106 bacteria/gm may results in emetic and diarrhoeal syndromes. The most common source of this bacterium is found in liquid food products, milk powder, mixed food products and is of particular concern in the baby formula industry. The electrochemical deposition technique, such as cyclic voltammetry, was used to develop and test a model DNA-based biosensor on a gold electrode electropolymerized with polypyrrole. The electrically conducting polymer, polypyrrole is used as a platform for immobilizing DNA (1μg) on the gold electrode surface, since it can be more easily deposited from neutral pH aqueous solutions of pyrrolemonomers. The average current peak during the electrodeposition event is 288μA. There is a clear change in the current after hybridization of the complementary oligonucleotide (6.35μA) and for the noncomplementary oligonucleotide (5.77μA). The drop in current after each event was clearly noticeable and it proved to be effective.

  18. Evolution and dynamics of megaplasmids with genome sizes larger than 100 kb in the Bacillus cereus group

    OpenAIRE

    Zheng, Jinshui; Peng, Donghai; Ruan, Lifang; Sun, Ming

    2013-01-01

    Background Plasmids play a crucial role in the evolution of bacterial genomes by mediating horizontal gene transfer. However, the origin and evolution of most plasmids remains unclear, especially for megaplasmids. Strains of the Bacillus cereus group contain up to 13 plasmids with genome sizes ranging from 2 kb to 600 kb, and thus can be used to study plasmid dynamics and evolution. Results This work studied the origin and evolution of 31 B. cereus group megaplasmids (>100 kb) focusing on the...

  19. Assessment of a new selective chromogenic Bacillus cereus group plating medium and use of enterobacterial autoinducer of growth for cultural identification of Bacillus species.

    Science.gov (United States)

    Reissbrodt, R; Rassbach, A; Burghardt, B; Rienäcker, I; Mietke, H; Schleif, J; Tschäpe, H; Lyte, M; Williams, P H

    2004-08-01

    A new chromogenic Bacillus cereus group plating medium permits differentiation of pathogenic Bacillus species by colony morphology and color. Probiotic B. cereus mutants were distinguished from wild-type strains by their susceptibilities to penicillin G or cefazolin. The enterobacterial autoinducer increased the sensitivity and the speed of enrichment of B. cereus and B. anthracis spores in serum-supplemented minimal salts medium (based on the standard American Petroleum Institute medium) and buffered peptone water. PMID:15297532

  20. Characterization of the spore-forming Bacillus cereus sensu lato group and Clostridium perfringens bacteria isolated from the Australian dairy farm environment

    OpenAIRE

    Dréan, Paul; McAuley, Catherine M.; Moore, Sean C.; Fegan, Narelle; Fox, Edward M.

    2015-01-01

    Background The Bacillus cereus sensu lato group and Clostridium perfringens are spore-forming bacteria often associated with food spoilage and which can cause emetic and diarrheal syndromes in humans and ruminants. This study characterised the phenotypes and genotypes of 50 Bacillus cereus s. l. isolates and 26 Clostridium perfringens isolates from dairy farms environments in Victoria, Australia. Results Five of the seven B. cereus s. l. species were isolated, and analysis of the population d...

  1. Phosphatidylcholine-Specific Phospholipase C and Sphingomyelinase Activities in Bacteria of the Bacillus cereus Group

    OpenAIRE

    Pomerantsev, A. P.; Kalnin, K. V.; Osorio, M.; Leppla, S H

    2003-01-01

    Bacillus anthracis is nonhemolytic, even though it is closely related to the highly hemolytic Bacillus cereus. Hemolysis by B. cereus results largely from the action of phosphatidylcholine-specific phospholipase C (PC-PLC) and sphingomyelinase (SPH), encoded by the plc and sph genes, respectively. In B. cereus, these genes are organized in an operon regulated by the global regulator PlcR. B. anthracis contains a highly similar cereolysin operon, but it is transcriptionally silent because the ...

  2. Influence of multi-year Bacillus thuringiensis subsp. israelensis on the abundance of B. cereus group populations in Swedish riparian wetland soils

    DEFF Research Database (Denmark)

    Hendriksen, Niels Bohse; Schneider, Salome; Tajrin, Tania;

    Bacillus thuringiensis subsp. israelensis (Bti) is a soil-born bacterium affiliated to the B. cereus group (Bcg, a group including the pathogens B. cereus, B. thuringiensis, and B. anthracis) and used in biocontrol products against nematoceran larvae. However, knowledge is limited on how long...

  3. gyrB as a phylogenetic discriminator for members of the Bacillus anthracis-cereus-thuringiensis group

    Science.gov (United States)

    La Duc, Myron T.; Satomi, Masataka; Agata, Norio; Venkateswaran, Kasthuri

    2004-01-01

    Bacillus anthracis, the causative agent of the human disease anthrax, Bacillus cereus, a food-borne pathogen capable of causing human illness, and Bacillus thuringiensis, a well-characterized insecticidal toxin producer, all cluster together within a very tight clade (B. cereus group) phylogenetically and are indistinguishable from one another via 16S rDNA sequence analysis. As new pathogens are continually emerging, it is imperative to devise a system capable of rapidly and accurately differentiating closely related, yet phenotypically distinct species. Although the gyrB gene has proven useful in discriminating closely related species, its sequence analysis has not yet been validated by DNA:DNA hybridization, the taxonomically accepted "gold standard". We phylogenetically characterized the gyrB sequences of various species and serotypes encompassed in the "B. cereus group," including lab strains and environmental isolates. Results were compared to those obtained from analyses of phenotypic characteristics, 16S rDNA sequence, DNA:DNA hybridization, and virulence factors. The gyrB gene proved more highly differential than 16S, while, at the same time, as analytical as costly and laborious DNA:DNA hybridization techniques in differentiating species within the B. cereus group.

  4. Detection and quantification of viable Bacillus cereus group species in milk by propidium monoazide quantitative real-time PCR.

    Science.gov (United States)

    Cattani, Fernanda; Barth, Valdir C; Nasário, Jéssica S R; Ferreira, Carlos A S; Oliveira, Sílvia D

    2016-04-01

    The Bacillus cereus group includes important spore-forming bacteria that present spoilage capability and may cause foodborne diseases. These microorganisms are traditionally evaluated in food using culturing methods, which can be laborious and time-consuming, and may also fail to detect bacteria in a viable but nonculturable state. The purpose of this study was to develop a quantitative real-time PCR (qPCR) combined with a propidium monoazide (PMA) treatment to analyze the contamination of UHT milk by B. cereus group species viable cells. Thirty micrograms per milliliter of PMA was shown to be the most effective concentration for reducing the PCR amplification of extracellular DNA and DNA from dead cells. The quantification limit of the PMA-qPCR assay was 7.5×10(2)cfu/mL of milk. One hundred thirty-five UHT milk samples were analyzed to evaluate the association of PMA to qPCR to selectively detect viable cells. The PMA-qPCR was able to detect B. cereus group species in 44 samples (32.6%), whereas qPCR without PMA detected 78 positive samples (57.8%). Therefore, the PMA probably inhibited the amplification of DNA from cells that were killed during UHT processing, which avoided an overestimation of bacterial cells when using qPCR and, thus, did not overvalue potential health risks. A culture-based method was also used to detect and quantify B. cereus sensu stricto in the same samples and showed positive results in 15 (11.1%) samples. The culture method and PMA-qPCR allowed the detection of B. cereus sensu stricto in quantities compatible with the infective dose required to cause foodborne disease in 3 samples, indicating that, depending on the storage conditions, even after UHT treatment, infective doses may be reached in ready-to-consume products. PMID:26830746

  5. Physical Characteristics of Spores of Food-Associated Isolates of the Bacillus cereus Group

    OpenAIRE

    Ankolekar, Chandrakant; Labbé, Ronald G.

    2009-01-01

    All 47 food-borne isolates of Bacillus cereus sensu stricto, as well as 10 of 12 food-borne, enterotoxigenic isolates of Bacillus thuringiensis, possessed appendages. Spores were moderately to highly hydrophobic, and each had a net negative charge. These characteristics indicate that spores of food-associated B. thuringiensis and not only B. cereus sensu stricto have high potential to adhere to inert surfaces.

  6. Bacillus anthracis-like bacteria and other B. cereus group members in a microbial community within the International Space Station: a challenge for rapid and easy molecular detection of virulent B. anthracis.

    Directory of Open Access Journals (Sweden)

    Sandra P van Tongeren

    Full Text Available For some microbial species, such as Bacillus anthracis, the etiologic agent of the disease anthrax, correct detection and identification by molecular methods can be problematic. The detection of virulent B. anthracis is challenging due to multiple virulence markers that need to be present in order for B. anthracis to be virulent and its close relationship to Bacillus cereus and other members of the B. cereus group. This is especially the case in environments where build-up of Bacillus spores can occur and several representatives of the B. cereus group may be present, which increases the chance for false-positives. In this study we show the presence of B. anthracis-like bacteria and other members of the B. cereus group in a microbial community within the human environment of the International Space Station and their preliminary identification by using conventional culturing as well as molecular techniques including 16S rDNA sequencing, PCR and real-time PCR. Our study shows that when monitoring the microbial hygiene in a given human environment, health risk assessment is troublesome in the case of virulent B. anthracis, especially if this should be done with rapid, easy to apply and on-site molecular methods.

  7. Identification, genetic diversity and cereulide producing ability of Bacillus cereus group strains isolated from Beninese traditional fermented food condiments

    DEFF Research Database (Denmark)

    Thorsen, Line; Azokpota, Paulin; Hansen, Bjarne Munk; Hounhouigan, D. Joseph; Jakobsen, Mogens

    Bacillus cereus sensu lato is often detected in spontaneously fermented African foods but is rarely identified to species level. Only some of the B. cereus group species are reported to be pathogenic to humans and identification to species level is necessary to estimate the safety of these products....... In the present study, a total of 19 Bacillus cereus group spp. isolated from afitin, iru and sonru, three spontaneously fermented African locust (Parkia biglobosa) bean based condiments produced in Benin, were investigated. The strains were isolated at 6, 12, 18, 24 and 48 h fermentation time. By...... using phenotypic and genotypic methods all of the isolates could be identified as B. cereus sensu stricto. The isolates were grouped according to their PM13 PCR (random amplification of polymorphic DNA PCR) fingerprint and formed two major clusters, one of which contained eight strains isolated from...

  8. Cooperation and the evolutionary ecology of bacterial virulence: the Bacillus cereus group as a novel study system.

    Science.gov (United States)

    Raymond, Ben; Bonsall, Michael B

    2013-08-01

    How significant is social evolution theory for the maintenance of virulence in natural populations? We assume that secreted, distantly acting virulence factors are highly likely to be cooperative public goods. Using this assumption, we discuss and critically assess the potential importance of social interactions for understanding the evolution, diversity and distribution of virulence in the Bacillus cereus group, a novel study system for microbial social biology. We conclude that dynamic equilibria in Cry toxin production, as well as strong spatial structure and population bottlenecks in hosts are the main ecological factors maintaining the cooperative secretion of virulence factors and argue that collective action has contributed to the evolution of narrow host range. Non-linearities in the benefits associated with public goods, as well as the lack of private secretion systems in the Firmicutes may also explain the prevalence and importance of distantly acting virulence factors in B. cereus and its relatives. PMID:23702950

  9. A novel multiplex PCR discriminates Bacillus anthracis and its genetically related strains from other Bacillus cereus group species.

    Directory of Open Access Journals (Sweden)

    Hirohito Ogawa

    Full Text Available Anthrax is an important zoonotic disease worldwide that is caused by Bacillus anthracis, a spore-forming pathogenic bacterium. A rapid and sensitive method to detect B. anthracis is important for anthrax risk management and control in animal cases to address public health issues. However, it has recently become difficult to identify B. anthracis by using previously reported molecular-based methods because of the emergence of B. cereus, which causes severe extra-intestinal infection, as well as the human pathogenic B. thuringiensis, both of which are genetically related to B. anthracis. The close genetic relation of chromosomal backgrounds has led to complexity of molecular-based diagnosis. In this study, we established a B. anthracis multiplex PCR that can screen for the presence of B. anthracis virulent plasmids and differentiate B. anthracis and its genetically related strains from other B. cereus group species. Six sets of primers targeting a chromosome of B. anthracis and B. anthracis-like strains, two virulent plasmids, pXO1 and pXO2, a bacterial gene, 16S rRNA gene, and a mammalian gene, actin-beta gene, were designed. The multiplex PCR detected approximately 3.0 CFU of B. anthracis DNA per PCR reaction and was sensitive to B. anthracis. The internal control primers also detected all bacterial and mammalian DNAs examined, indicating the practical applicability of this assay as it enables monitoring of appropriate amplification. The assay was also applied for detection of clinical strains genetically related to B. anthracis, which were B. cereus strains isolated from outbreaks of hospital infections in Japan, and field strains isolated in Zambia, and the assay differentiated B. anthracis and its genetically related strains from other B. cereus group strains. Taken together, the results indicate that the newly developed multiplex PCR is a sensitive and practical method for detecting B. anthracis.

  10. The identification of a tetracycline resistance gene tet(M), on a Tn916-like transposon, in the Bacillus cereus group

    DEFF Research Database (Denmark)

    Agersø, Yvonne; Jensen, Lars Bogø; Givskov, Michael Christian;

    2002-01-01

    In order to investigate whether resistance genes present in bacteria in manure could transfer to indigenous soil bacteria, resistant isolates belonging to the Bacillus cereus group (Bacillus cereus, Bacillus anthracis and Bacillus thuringiensis) were isolated from farm soil (72 isolates) and manure.......1%) isolates did not contain any of the tested genes. All tet(M) positive isolates carried transposon Tn916 and could transfer this mobile DNA element to other Gram-positive bacteria....

  11. The Phylogeny of Bacillus cereus sensu lato.

    Science.gov (United States)

    Okinaka, Richard T; Keim, Paul

    2016-02-01

    The three main species of the Bacillus cereus sensu lato, B. cereus, B. thuringiensis, and B. anthracis, were recognized and established by the early 1900s because they each exhibited distinct phenotypic traits. B. thuringiensis isolates and their parasporal crystal proteins have long been established as a natural pesticide and insect pathogen. B. anthracis, the etiological agent for anthrax, was used by Robert Koch in the 19th century as a model to develop the germ theory of disease, and B. cereus, a common soil organism, is also an occasional opportunistic pathogen of humans. In addition to these three historical species designations, are three less-recognized and -understood species: B. mycoides, B. weihenstephanensis, and B. pseudomycoides. All of these "species" combined comprise the Bacillus cereus sensu lato group. Despite these apparently clear phenotypic definitions, early molecular approaches to separate the first three by various DNA hybridization and 16S/23S ribosomal sequence analyses led to some "confusion" because there were limited differences to differentiate between these species. These and other results have led to frequent suggestions that a taxonomic change was warranted to reclassify this group to a single species. But the pathogenic properties of B. anthracis and the biopesticide applications of B. thuringiensis appear to "have outweighed pure taxonomic considerations" and the separate species categories are still being maintained. B. cereus sensu lato represents a classic example of a now common bacterial species taxonomic quandary. PMID:26999390

  12. Environmental factors determining the epidemiology and population genetic structure of the Bacillus cereus group in the field.

    Science.gov (United States)

    Raymond, Ben; Wyres, Kelly L; Sheppard, Samuel K; Ellis, Richard J; Bonsall, Michael B

    2010-05-01

    Bacillus thuringiensis (Bt) and its insecticidal toxins are widely exploited in microbial biopesticides and genetically modified crops. Its population biology is, however, poorly understood. Important issues for the safe, sustainable exploitation of Bt include understanding how selection maintains expression of insecticidal toxins in nature, whether entomopathogenic Bt is ecologically distinct from related human pathogens in the Bacillus cereus group, and how the use of microbial pesticides alters natural bacterial populations. We addressed these questions with a MLST scheme applied to a field experiment in which we excluded/added insect hosts and microbial pesticides in a factorial design. The presence of insects increased the density of Bt/B. cereus in the soil and the proportion of strains expressing insecticidal toxins. We found a near-epidemic population structure dominated by a single entomopathogenic genotype (ST8) in sprayed and unsprayed enclosures. Biopesticidal ST8 proliferated in hosts after spraying but was also found naturally associated with leaves more than any other genotype. In an independent experiment several ST8 isolates proved better than a range of non-pathogenic STs at endophytic and epiphytic colonization of seedlings from soil. This is the first experimental demonstration of Bt behaving as a specialized insect pathogen in the field. These data provide a basis for understanding both Bt ecology and the influence of anthropogenic factors on Bt populations. This natural population of Bt showed habitat associations and a population structure that differed markedly from previous MLST studies of less ecologically coherent B. cereus sample collections. The host-specific adaptations of ST8, its close association with its toxin plasmid and its high prevalence within its clade are analogous to the biology of Bacillus anthracis. This prevalence also suggests that selection for resistance to the insecticidal toxins of ST8 will have been stronger than

  13. Environmental Factors Determining the Epidemiology and Population Genetic Structure of the Bacillus cereus Group in the Field

    Science.gov (United States)

    Raymond, Ben; Wyres, Kelly L.; Sheppard, Samuel K.; Ellis, Richard J.; Bonsall, Michael B.

    2010-01-01

    Bacillus thuringiensis (Bt) and its insecticidal toxins are widely exploited in microbial biopesticides and genetically modified crops. Its population biology is, however, poorly understood. Important issues for the safe, sustainable exploitation of Bt include understanding how selection maintains expression of insecticidal toxins in nature, whether entomopathogenic Bt is ecologically distinct from related human pathogens in the Bacillus cereus group, and how the use of microbial pesticides alters natural bacterial populations. We addressed these questions with a MLST scheme applied to a field experiment in which we excluded/added insect hosts and microbial pesticides in a factorial design. The presence of insects increased the density of Bt/B. cereus in the soil and the proportion of strains expressing insecticidal toxins. We found a near-epidemic population structure dominated by a single entomopathogenic genotype (ST8) in sprayed and unsprayed enclosures. Biopesticidal ST8 proliferated in hosts after spraying but was also found naturally associated with leaves more than any other genotype. In an independent experiment several ST8 isolates proved better than a range of non-pathogenic STs at endophytic and epiphytic colonization of seedlings from soil. This is the first experimental demonstration of Bt behaving as a specialized insect pathogen in the field. These data provide a basis for understanding both Bt ecology and the influence of anthropogenic factors on Bt populations. This natural population of Bt showed habitat associations and a population structure that differed markedly from previous MLST studies of less ecologically coherent B. cereus sample collections. The host-specific adaptations of ST8, its close association with its toxin plasmid and its high prevalence within its clade are analogous to the biology of Bacillus anthracis. This prevalence also suggests that selection for resistance to the insecticidal toxins of ST8 will have been stronger than

  14. Environmental factors determining the epidemiology and population genetic structure of the Bacillus cereus group in the field.

    Directory of Open Access Journals (Sweden)

    Ben Raymond

    2010-05-01

    Full Text Available Bacillus thuringiensis (Bt and its insecticidal toxins are widely exploited in microbial biopesticides and genetically modified crops. Its population biology is, however, poorly understood. Important issues for the safe, sustainable exploitation of Bt include understanding how selection maintains expression of insecticidal toxins in nature, whether entomopathogenic Bt is ecologically distinct from related human pathogens in the Bacillus cereus group, and how the use of microbial pesticides alters natural bacterial populations. We addressed these questions with a MLST scheme applied to a field experiment in which we excluded/added insect hosts and microbial pesticides in a factorial design. The presence of insects increased the density of Bt/B. cereus in the soil and the proportion of strains expressing insecticidal toxins. We found a near-epidemic population structure dominated by a single entomopathogenic genotype (ST8 in sprayed and unsprayed enclosures. Biopesticidal ST8 proliferated in hosts after spraying but was also found naturally associated with leaves more than any other genotype. In an independent experiment several ST8 isolates proved better than a range of non-pathogenic STs at endophytic and epiphytic colonization of seedlings from soil. This is the first experimental demonstration of Bt behaving as a specialized insect pathogen in the field. These data provide a basis for understanding both Bt ecology and the influence of anthropogenic factors on Bt populations. This natural population of Bt showed habitat associations and a population structure that differed markedly from previous MLST studies of less ecologically coherent B. cereus sample collections. The host-specific adaptations of ST8, its close association with its toxin plasmid and its high prevalence within its clade are analogous to the biology of Bacillus anthracis. This prevalence also suggests that selection for resistance to the insecticidal toxins of ST8 will have

  15. Possible use of bacteriophages active against Bacillus anthracis and other B. cereus group members in the face of a bioterrorism threat.

    Science.gov (United States)

    Jończyk-Matysiak, Ewa; Kłak, Marlena; Weber-Dąbrowska, Beata; Borysowski, Jan; Górski, Andrzej

    2014-01-01

    Anthrax is an infectious fatal disease with epidemic potential. Nowadays, bioterrorism using Bacillus anthracis is a real possibility, and thus society needs an effective weapon to neutralize this threat. The pathogen may be easily transmitted to human populations. It is easy to store, transport, and disseminate and may survive for many decades. Recent data strongly support the effectiveness of bacteriophage in treating bacterial diseases. Moreover, it is clear that bacteriophages should be considered a potential incapacitative agent against bioterrorism using bacteria belonging to B. cereus group, especially B. anthracis. Therefore, we have reviewed the possibility of using bacteriophages active against Bacillus anthracis and other species of the B. cereus group in the face of a bioterrorism threat. PMID:25247187

  16. Effect of relevant environmental factors for food preservation and molecular identification (High Resolution Melting) of Bacillus cereus group

    OpenAIRE

    Antolinos López, Vera

    2011-01-01

    [SPA]Los microorganismos pertenecientes al grupo Bacillus cereus poseen importancia económica y para la salud pública. De entre todos ellos, Bacillus cereus sensu stricto es el agente causal de enfermedades gastrointestinales y Bacillus weihenstephanensis es una especie psicrótrofa capaz de crecer a temperaturas entre 4 y 7ºC. Además, ambos son responsables de pérdidas económicas relevantes derivadas del deterioro de alimentos. Debido a su habilidad para formar endosporos altamente resistente...

  17. Genotyping of Bacillus cereus strains by microarray-based resequencing.

    Directory of Open Access Journals (Sweden)

    Michael E Zwick

    Full Text Available The ability to distinguish microbial pathogens from closely related but nonpathogenic strains is key to understanding the population biology of these organisms. In this regard, Bacillus anthracis, the bacterium that causes inhalational anthrax, is of interest because it is closely related and often difficult to distinguish from other members of the B. cereus group that can cause diverse diseases. We employed custom-designed resequencing arrays (RAs based on the genome sequence of Bacillus anthracis to generate 422 kb of genomic sequence from a panel of 41 Bacillus cereus sensu lato strains. Here we show that RAs represent a "one reaction" genotyping technology with the ability to discriminate between highly similar B. anthracis isolates and more divergent strains of the B. cereus s.l. Clade 1. Our data show that RAs can be an efficient genotyping technology for pre-screening the genetic diversity of large strain collections to selected the best candidates for whole genome sequencing.

  18. Bacillus anthracis-like bacteria and other B. cereus group members in a microbial community within the international space station: a challenge for rapid and easy molecular detection of virulent B. anthracis.

    OpenAIRE

    Tongeren, van, F.W.; Roest, H.I.J.; Degener, J. E.; Harmsen, H. J. M.

    2014-01-01

    For some microbial species, such as Bacillus anthracis, the etiologic agent of the disease anthrax, correct detection and identification by molecular methods can be problematic. The detection of virulent B. anthracis is challenging due to multiple virulence markers that need to be present in order for B. anthracis to be virulent and its close relationship to Bacillus cereus and other members of the B. cereus group. This is especially the case in environments where build-up of Bacillus spores ...

  19. Rapid screening test for enterotoxin-producing Bacillus cereus.

    OpenAIRE

    Jackson, S G

    1993-01-01

    Culture supernatants of 30 enterotoxin-producing Bacillus cereus isolates produced a characteristic progressive destruction of McCoy cell monolayers. Enterotoxin-negative B. cereus and other group 1 Bacillus spp. caused no monolayer disruption. The McCoy cell tissue culture system appears to provide a rapid screening assay for detection of enterotoxin-producing B. cereus.

  20. Biodiversity in Bacillus cereus

    NARCIS (Netherlands)

    Pielaat A; Fricker M; Nauta MJ; Leusden FM van; MGB

    2006-01-01

    Experiments have been performed by different partners to identify variability in properties of Bacillus cereus strains that contribute to the extent of their virulence as part of an EU project. To this end, 100 B. cereus strains were selected and screened for biological properties, such as toxin pro

  1. Reliable radiogenic heat production of representative lithological groups

    Science.gov (United States)

    Vilà, Miquel; Fernández, Manel

    2010-05-01

    Determining the temperature distribution within the lithosphere requires the knowledge of the radiogenic heat production (RHP) distribution within the crust and the lithospheric mantle. RHP of crustal rocks varies considerably at different scales as a result of the petrogenetic processes responsible for their formation and therefore RHP depends on the considered lithologies. In this work we address RHP variability of some common lithological groups from a compilation of a total of 2188 representative U, Th and K concentrations of different worldwide rock types derived from 102 geochemical and geophysical datasets previously published. To optimize the use of the generated RHP database we have classified and renamed the rock-type denominations of the original works following a petrologic classification scheme with a hierarchical structure. To compute RHP a reasonable average density was assigned for each lithologic group. The RHP data of each lithological group is presented in cumulative distribution plots, and we report a table with the mean, the standard deviation, the minimum and maximum values, and the significant percentiles (10th, 25th, 50th, 75th and 90th) of these lithological groups. In general, for each lithological group exists a wide zone around the median value with a constant slope indicating RHP values with the same probability of occurrence. This zone usually includes the RHP range defined by the 25th and the 75th percentile. When compare previuos RHP estimates of representative lithological groups with our results it is observed that most of them fall between the 25th and 75th percentiles obtained. We integrate our results in a schematic model of the differentiation processes undergone by lithospheric rocks. This model allows us to discuss the RHP variability for the different igneous, sedimentary and metamorphic lithological groups from a petrogenetic viewpoint. Finally we give some useful guidelines to assign RHP values to lithospheric thermal

  2. Pathogenomic Sequence Analysis of Bacillus cereus and Bacillus thuringiensis Isolates Closely Related to Bacillus anthracis

    OpenAIRE

    Han, Cliff S.; Xie, Gary; Challacombe, Jean F.; Altherr, Michael R.; Bhotika, Smriti S.; Bruce, David; Campbell, Connie S.; Campbell, Mary L.; Chen, Jin; Chertkov, Olga; Cleland, Cathy; Dimitrijevic, Mira; Doggett, Norman A.; Fawcett, John J.; Glavina, Tijana

    2006-01-01

    Bacillus anthracis, Bacillus cereus, and Bacillus thuringiensis are closely related gram-positive, spore-forming bacteria of the B. cereus sensu lato group. While independently derived strains of B. anthracis reveal conspicuous sequence homogeneity, environmental isolates of B. cereus and B. thuringiensis exhibit extensive genetic diversity. Here we report the sequencing and comparative analysis of the genomes of two members of the B. cereus group, B. thuringiensis 97-27 subsp. konkukian sero...

  3. Specific Detection of the Gene for the Extracellular Neutral Protease of Bacillus cereus by PCR and Blot Hybridization

    OpenAIRE

    Bach, H.-J.; Errampalli, D.; Leung, K. T.; Lee, H.; Hartmann, A; Trevors, J. T.; Munch, J C

    1999-01-01

    A pair of primers and a gene probe for the amplification and detection of the Bacillus cereus neutral protease gene (NPRC) were developed. Specificity for the npr genes of the B. cereus group members B. cereus, B. mycoides, and B. thuringiensis was shown. Restriction polymorphism patterns of the PCR products confirmed the presence of the NPRC gene in all three species.

  4. Electric DNA arrays for determination of pathogenic Bacillus cereus

    OpenAIRE

    Liu, Yanling

    2007-01-01

    Silicon-based electric chip arrays were developed for characterization of Bacillus cereus with respect to the capacity to produce toxins involved in food poisoning and foodborne infections. Bacteria of the B. cereus group contain different sets of four toxins encoded by eight genes. The purpose of this work was to develop a fast method for determination of the presence of these genes in colonies from primary enrichment cultures. The specific DNA detection was based on immobilization of DNA ca...

  5. Glycosylation of BclA Glycoprotein from Bacillus cereus and Bacillus anthracis Exosporium Is Domain-specific.

    Science.gov (United States)

    Maes, Emmanuel; Krzewinski, Frederic; Garenaux, Estelle; Lequette, Yannick; Coddeville, Bernadette; Trivelli, Xavier; Ronse, Annette; Faille, Christine; Guerardel, Yann

    2016-04-29

    The spores of the Bacillus cereus group (B. cereus, Bacillus anthracis, and Bacillus thuringiensis) are surrounded by a paracrystalline flexible yet resistant layer called exosporium that plays a major role in spore adhesion and virulence. The major constituent of its hairlike surface, the trimerized glycoprotein BclA, is attached to the basal layer through an N-terminal domain. It is then followed by a repetitive collagen-like neck bearing a globular head (C-terminal domain) that promotes glycoprotein trimerization. The collagen-like region of B. anthracis is known to be densely substituted by unusual O-glycans that may be used for developing species-specific diagnostics of B. anthracis spores and thus targeted therapeutic interventions. In the present study, we have explored the species and domain specificity of BclA glycosylation within the B. cereus group. First, we have established that the collagen-like regions of both B. anthracis and B. cereus are similarly substituted by short O-glycans that bear the species-specific deoxyhexose residues anthrose and the newly observed cereose, respectively. Second we have discovered that the C-terminal globular domains of BclA from both species are substituted by polysaccharide-like O-linked glycans whose structures are also species-specific. The presence of large carbohydrate polymers covering the surface of Bacillus spores may have a profound impact on the way that spores regulate their interactions with biotic and abiotic surfaces and represents potential new diagnostic targets. PMID:26921321

  6. Bacillus anthracis, Bacillus cereus, and Bacillus thuringiensis—One Species on the Basis of Genetic Evidence

    OpenAIRE

    Helgason, Erlendur; Økstad, Ole Andreas; Dominique A. Caugant; Johansen, Henning A.; Fouet, Agnes; Mock, Michéle; Hegna, Ida; Kolstø, Anne-Brit

    2000-01-01

    Bacillus anthracis, Bacillus cereus, and Bacillus thuringiensis are members of the Bacillus cereus group of bacteria, demonstrating widely different phenotypes and pathological effects. B. anthracis causes the acute fatal disease anthrax and is a potential biological weapon due to its high toxicity. B. thuringiensis produces intracellular protein crystals toxic to a wide number of insect larvae and is the most commonly used biological pesticide worldwide. B. cereus is a probably ubiquitous so...

  7. Genetic Grouping of Medulloblastomas by Representative Markers in Pathologic Diagnosis1

    OpenAIRE

    Min, Hye Sook; Lee, Ji Yeoun; Kim, Seung-Ki; Park, Sung-Hye

    2013-01-01

    A recent analysis of the genetic features of medulloblastoma (MB) suggested classification into distinct subgroups according to gene expression profiles, including the Wingless signaling pathway-activated group (WNT group), the Sonic Hedgehog signaling pathway-activated group (SHH group), group 3, and group 4. To classify MB according to genetic features in practice, we analyzed 74 MBs using representative markers of each group. Based on immunohistochemistries (IHC), cytogenetic alterations, ...

  8. Linking Bacillus cereus Genotypes and Carbohydrate Utilization Capacity

    Science.gov (United States)

    Warda, Alicja K.; Siezen, Roland J.; Boekhorst, Jos; Wells-Bennik, Marjon H. J.; de Jong, Anne; Kuipers, Oscar P.; Nierop Groot, Masja N.; Abee, Tjakko

    2016-01-01

    We characterised carbohydrate utilisation of 20 newly sequenced Bacillus cereus strains isolated from food products and food processing environments and two laboratory strains, B. cereus ATCC 10987 and B. cereus ATCC 14579. Subsequently, genome sequences of these strains were analysed together with 11 additional B. cereus reference genomes to provide an overview of the different types of carbohydrate transporters and utilization systems found in B. cereus strains. The combined application of API tests, defined growth media experiments and comparative genomics enabled us to link the carbohydrate utilisation capacity of 22 B. cereus strains with their genome content and in some cases to the panC phylogenetic grouping. A core set of carbohydrates including glucose, fructose, maltose, trehalose, N-acetyl-glucosamine, and ribose could be used by all strains, whereas utilisation of other carbohydrates like xylose, galactose, and lactose, and typical host-derived carbohydrates such as fucose, mannose, N-acetyl-galactosamine and inositol is limited to a subset of strains. Finally, the roles of selected carbohydrate transporters and utilisation systems in specific niches such as soil, foods and the human host are discussed. PMID:27272929

  9. Linking Bacillus cereus Genotypes and Carbohydrate Utilization Capacity.

    Directory of Open Access Journals (Sweden)

    Alicja K Warda

    Full Text Available We characterised carbohydrate utilisation of 20 newly sequenced Bacillus cereus strains isolated from food products and food processing environments and two laboratory strains, B. cereus ATCC 10987 and B. cereus ATCC 14579. Subsequently, genome sequences of these strains were analysed together with 11 additional B. cereus reference genomes to provide an overview of the different types of carbohydrate transporters and utilization systems found in B. cereus strains. The combined application of API tests, defined growth media experiments and comparative genomics enabled us to link the carbohydrate utilisation capacity of 22 B. cereus strains with their genome content and in some cases to the panC phylogenetic grouping. A core set of carbohydrates including glucose, fructose, maltose, trehalose, N-acetyl-glucosamine, and ribose could be used by all strains, whereas utilisation of other carbohydrates like xylose, galactose, and lactose, and typical host-derived carbohydrates such as fucose, mannose, N-acetyl-galactosamine and inositol is limited to a subset of strains. Finally, the roles of selected carbohydrate transporters and utilisation systems in specific niches such as soil, foods and the human host are discussed.

  10. Linking Bacillus cereus Genotypes and Carbohydrate Utilization Capacity.

    Science.gov (United States)

    Warda, Alicja K; Siezen, Roland J; Boekhorst, Jos; Wells-Bennik, Marjon H J; de Jong, Anne; Kuipers, Oscar P; Nierop Groot, Masja N; Abee, Tjakko

    2016-01-01

    We characterised carbohydrate utilisation of 20 newly sequenced Bacillus cereus strains isolated from food products and food processing environments and two laboratory strains, B. cereus ATCC 10987 and B. cereus ATCC 14579. Subsequently, genome sequences of these strains were analysed together with 11 additional B. cereus reference genomes to provide an overview of the different types of carbohydrate transporters and utilization systems found in B. cereus strains. The combined application of API tests, defined growth media experiments and comparative genomics enabled us to link the carbohydrate utilisation capacity of 22 B. cereus strains with their genome content and in some cases to the panC phylogenetic grouping. A core set of carbohydrates including glucose, fructose, maltose, trehalose, N-acetyl-glucosamine, and ribose could be used by all strains, whereas utilisation of other carbohydrates like xylose, galactose, and lactose, and typical host-derived carbohydrates such as fucose, mannose, N-acetyl-galactosamine and inositol is limited to a subset of strains. Finally, the roles of selected carbohydrate transporters and utilisation systems in specific niches such as soil, foods and the human host are discussed. PMID:27272929

  11. BACILLUS CEREUS: ISOLATION IN JENNET MILK

    Directory of Open Access Journals (Sweden)

    M.L. Scatassa

    2011-01-01

    Full Text Available Jennet milk as human food is hypoallergenic for patients affected by Cow Milk Protein Allergy and multiple food allergies. For these pathologies, jennet milk represents the best alternative to other types of milk. Therefore, jennet milk consumers are very sensible to the effects of pathogens' contaminations, and several hygienic practices during the milk production need to be adopted. During regular monitoring in one Sicilian jennet farm, Bacillus cereus in the milk was detected. In 3 bulk milk samples (maximum concentration: 1.2 x 103 ufc/ml, in 3 individual milk samples (10, 20 e 60 ufc/ml, in the milk filter (5 ufc/cm2, in the soil (maximum concentration: 1.5 x 103 ufc/g, on the hands and the gloves of two milkers, on the animal hide (from 1 to 3 ufc/cm2. No spores were detected. A total of 8 Bacillus cereus s.s. strains were analyzed for diarrhoic toxin, and 6 strains producing enterotoxins resulted. The improvement of environmental and milking hygienic conditions reduced Bacillus cereus concentration.

  12. The Pathogenomic Sequence Analysis of B. cereus and B. Thuringiensis isolates closely related to Bacillus anthracis

    Energy Technology Data Exchange (ETDEWEB)

    Han, C S; Xie, G; Challacombe, J F; Altherr, M R; Bhotika, S S; Bruce, D; Campbell, C S; Campbell, M L; Chen, J; Chertkov, O; Cleland, C; Dimitrijevic-Bussod, M; Doggett, N A; Fawcett, J J; Glavina, T; Goodwin, L A; Hill, K K; Hitchcock, P; Jackson, P J; Keim, P; Kewalramani, A R; Longmire, J; Lucas, S; Malfatti, S; McMurry, K; Meincke, L J; Misra, M; Moseman, B L; Mundt, M; Munk, A C; Okinaka, R T; Parson-Quintana, B; Reilly, L P; Richardson, P; Robinson, D L; Rubin, E; Saunders, E; Tapia, R; Tesmer, J G; Thayer, N; Thompson, L S; Tice, H; Ticknor, L O; Wills, P L; Gilna, P; Brettin, T S

    2005-10-12

    The sequencing and analysis of two close relatives of Bacillus anthracis are reported. AFLP analysis of over 300 isolates of B. cereus, B. thuringiensis and B. anthracis identified two isolates as being very closely related to B. anthracis. One, a B. cereus, BcE33L, was isolated from a zebra carcass in Nambia; the second, a B. thuringiensis, 97-27, was isolated from a necrotic human wound. The B. cereus appears to be the closest anthracis relative sequenced to date. A core genome of over 3,900 genes was compiled for the Bacillus cereus group, including B anthracis. Comparative analysis of these two genomes with other members of the B. cereus group provides insight into the evolutionary relationships among these organisms. Evidence is presented that differential regulation modulates virulence, rather than simple acquisition of virulence factors. These genome sequences provide insight into the molecular mechanisms contributing to the host range and virulence of this group of organisms.

  13. Forming Representative Household and Factor Groups for a South African SAM

    OpenAIRE

    Pauw, Kalie

    2005-01-01

    This Technical Paper explains the formation of representative households and factor groups for inclusion in the PROVIDE Project Social Accounting Matrix. A general guideline for forming household and/or factor groups is that they should reproduce the socio-economic stratification within the society as accurately as possible. Such groups should also be made up of 'relatively homogenous' groups that are easily recognisable for policy purposes. Here the Income and Expenditure Survey (2000) and L...

  14. Attitudes Towards (Psychotherapy) Groups: Results of a Survey in a Representative Sample.

    Science.gov (United States)

    Strauss, Bernhard; Spangenberg, Lena; Brähler, Elmar; Bormann, Bianca

    2015-07-01

    Based upon observations indicating decreasing attractiveness of groups within and outside the clinical field, the present study aimed to determine attitudes toward, and expectations of, groups in a representative sample of 2512 German citizens. The survey also included questions specifically related to group psychotherapy and its acceptance. In addition, psychological characteristics of respondents (measures of narcissism, psychological impairment, and emotion regulation) and socio-demographic variables were assessed to examine their potential association with group-related attitudes. In total, the survey revealed a relatively positive picture of attitudes and expectations toward groups in general and psychotherapy groups in particular. Those with more open attitudes towards groups were comparatively less distressed, anxious, and depressed; they favored emotional reappraisal instead of suppression as the dominant strategy to regulate their emotions. Contrary to prediction, narcissism did not influence attitudes towards groups. The results are related to current discussions of the attractiveness of groups and to implications for the practice of group psychotherapy. PMID:24963534

  15. Fate of pathogenic Bacillus cereus spores after ingestion by protist grazers

    DEFF Research Database (Denmark)

    Winding, Anne; Santos, Susana; Hendriksen, Niels Bohse; Jakobsen, Hans

    evolution of Bacillus cereus group bacteria (e.g. B. cereus, B. anthracis, B. thuringiensis) as a pathogen. It has been hypothesized that the spore stage protects against digestion by predating protists. Indeed, B. thuringiensis spores have been shown to be readily ingested by ciliated protists but failed...... to be digested (Manasherob et al 1998 AEM 64:1750-). Here we report how diverse protist grazers grow on both vegetative cells and spores of B. cereus and how the bacteria survive ingestion and digestion, and even proliferate inside the digestive vacuoles of ciliated protists. The survival ability of...... B. cereus was initially investigated in microcosms inoculated with pure cultures of the protists Acanthamoeba castellanii, Tetrahymena pyriformis and Cercomonas sp. as grazers. Individual protist cultures were fed with fluorescently labelled (CellTracker™RedCMTPX) B. cereus spores or vegetative...

  16. Obesity risk factors in a representative group of Polish prepubertal children

    OpenAIRE

    Januszek-Trzciąkowska, Aleksandra; Małecka-Tendera, Ewa; Klimek, Katarzyna; Matusik, Paweł

    2013-01-01

    Introduction The study aim was to evaluate risk factors of obesity in Polish children aged 7 to 9 years. Material and methods A representative group of 2571 children (1268 girls and 1303 boys) was randomly selected according to the European Childhood Obesity Group protocol. Weight and height were measured and body mass index (BMI) was calculated. A questionnaire was completed by the children's parents with respect to behavioural and family-related risk factors of obesity. International Obesit...

  17. Under-Represented Groups in Post-Secondary Education in Ontario and the Republic of Ireland

    Science.gov (United States)

    Cheng-Hoy, April

    2012-01-01

    Increasing access to and participation in post-secondary education (PSE) for students with disabilities, from low-income families, and with parents who do not have any PSE are common issues that Ontario and the Republic of Ireland are currently facing. The barriers confronted by these under-represented groups in both PSE systems are often complex,…

  18. The Fundamental Group of a Spatial Section Represented by a Topspin Network

    OpenAIRE

    Duston, Christopher L

    2013-01-01

    We present an algorithm which determines the fundamental group of a spatial section using topspin networks. Tracking the topology of the spatial section is a unique feature of this approach, which is not possible in standard Loop Quantum Gravity. This leads to an example of spatial topology change in a smooth 4-manifold represented by a topspin foam.

  19. A survey of the southernmost representatives of the tricolor species group, genus Phalotris (Serpentes, Colubridae

    Directory of Open Access Journals (Sweden)

    Geraldo C. Leynaud

    2005-12-01

    Full Text Available Colubrid snakes of the South American genus Phalotris are difficult to detect because of their secretive habits, and thus they are poorly represented in collections. The species Phalotris cuyanus and P. tricolor, the southernmost representatives of the tricolor species group, were studied to determine the limits of intraspecific variation of P. cuyanus and to consolidate the taxonomic relationship between both species, the phenetically and geographically closest members in the group. The distribution of selected external characters (cephalic, ventral and subcaudal scales, coloration pattern, width of white and black collars, and hemipenis morphology were analyzed. Comparative data on the other members of the group, P. mertensi and P. matogrossensis, are briefly discussed. Males of P. cuyanus have a higher number of ventral scales than males of P. tricolor (mean of 220.3 vs. 204.6. Cephalic melanism varies among individuals and does not have discriminant orgeographic value for this species group. The white nuchal collar may partially cover the parietal scales in the four species. The black collar is moderately narrow in P. cuyanus, but it can be up to 12 scales wide in P. tricolor. Vertebral dotting is neither constant nor exclusive of any species. The four species of the group are wellcharacterized by combinations of character states for each one. We suggest considering to P. cuyanus as an evolutionary species typical of the Monte biogeographic province.

  20. Bacillus cereus in Brazilian Ultra High Temperature milk Bacillus cereus em leite UHT brasileiro

    Directory of Open Access Journals (Sweden)

    Cristiana de Paula Pacheco-Sanchez

    2007-01-01

    Full Text Available Brazilian Ultra High Temperature (UHT milk consumption has increased during the last decade from 187 to 4,200 million liters. In the continuous UHT process, milk is submitted for 2-4 s to 130-150ºC, in a continuous flow system with immediate refrigeration and aseptical packing in hermetic packages. This research had the purpose to verify the incidence of B. cereus species from the B. cereus group, in UHT milk. In 1998 high indexes of these organisms were reported, reaching 34.14% of the analyzed samples. Beyond this fact, there was the need to establish methods and processes adjusted for correct identification of B. cereus. Thus, commercial sterility tests of 6,500 UHT milk packages were investigated in two assays, after ten days incubation at 37ºC and 7ºC to germinate all possible spores and/or to recuperate injured vegetative cells followed by pH measurement. Samples (1,300 packages each from five Brazilian UHT plants of whole UHT milk processed by direct steam injection, packaged in carton were investigated for the presence of Bacillus cereus through phenotypic and genetic (PCR tests. Values of pH were different for the samples, ranging between 6.57 and 6.73. After storage of the samples, only four packages with pH measurement below the lower limit of 6.5 were found and analyzed for the presence of B. cereus. This organism was not detected in any of the samples indicating that the five Brazilian UHT milk processors control pathogenic microorganisms and it can be said that the consumption of UHT milk does not present safety problems to consumers. Fourier Transform Infrared Spectroscopy (FTIR and PCR tests were efficient and must be adopted to confirm the biochemical series for B. cereus.O consumo de leite ultra-alta temperatura (UHT brasileiro aumentou, durante a última década, de 187 milhões de litros para 4,200 milhões de litros. No processo contínuo de leite UHT o leite é submetido por 2-4 seg a 130-150ºC, em sistemas de

  1. Probiotic Bacillus cereus Strains, a Potential Risk for Public Health in China

    Science.gov (United States)

    Zhu, Kui; Hölzel, Christina S.; Cui, Yifang; Mayer, Ricarda; Wang, Yang; Dietrich, Richard; Didier, Andrea; Bassitta, Rupert; Märtlbauer, Erwin; Ding, Shuangyang

    2016-01-01

    Bacillus cereus is an important cause of foodborne infectious disease and food poisoning. However, B. cereus has also been used as a probiotic in human medicine and livestock production, with low standards of safety assessment. In this study, we evaluated the safety of 15 commercial probiotic B. cereus preparations from China in terms of mislabeling, toxin production, and transferable antimicrobial resistance. Most preparations were incorrectly labeled, as they contained additional bacterial species; one product did not contain viable B. cereus at all. In total, 18 B. cereus group strains—specifically B. cereus and Bacillus thuringiensis—were isolated. Enterotoxin genes nhe, hbl, and cytK1, as well as the ces-gene were assessed by PCR. Enterotoxin production and cytotoxicity were confirmed by ELISA and cell culture assays, respectively. All isolated B. cereus group strains produced the enterotoxin Nhe; 15 strains additionally produced Hbl. Antimicrobial resistance was assessed by microdilution; resistance genes were detected by PCR and further characterized by sequencing, transformation and conjugation assays. Nearly half of the strains harbored the antimicrobial resistance gene tet(45). In one strain, tet(45) was situated on a mobile genetic element—encoding a site-specific recombination mechanism—and was transferable to Staphylococcus aureus and Bacillus subtilis by electro-transformation. In view of the wide and uncontrolled use of these products, stricter regulations for safety assessment, including determination of virulence factors and transferable antimicrobial resistance genes, are urgently needed. PMID:27242738

  2. Tenth working group meeting of representatives of RCA Member States. Report

    International Nuclear Information System (INIS)

    The Tenth RCA (Regional Co-operative Agreement for Research, Development and Training Related to Nuclear Science and Technology) Working Group meeting of representatives of RCA Member States was held at the Chinese Academy of Agricultural Sciences, Beijing, between 11-14 April 1988. The report on the meeting consists of a presentation of the seven technical sessions which dealt with topics such as nuclear techniques in industry, agriculture and medicine, nuclear power and of the project reports under RCA

  3. Secondary cell wall polysaccharides in Bacillus anthracis and Bacillus cereus strains

    OpenAIRE

    Leoff, Christine

    2009-01-01

    This thesis presents a systematic comparison of cell wall carbohydrates, in particular the non classical secondary cell wall polysaccharides from closely related strains within the Bacillus cereus group. The results suggest that the cell wall glycosyl composition of the various Bacillus cereus group strains display differences that correlate with their phylogenetic relatedness. Comparative structural analysis of polysaccharide components that were released from the cell walls of the various s...

  4. Phages Preying on Bacillus anthracis, Bacillus cereus, and Bacillus thuringiensis: Past, Present and Future

    OpenAIRE

    Annika Gillis; Jacques Mahillon

    2014-01-01

    Many bacteriophages (phages) have been widely studied due to their major role in virulence evolution of bacterial pathogens. However, less attention has been paid to phages preying on bacteria from the Bacillus cereus group and their contribution to the bacterial genetic pool has been disregarded. Therefore, this review brings together the main information for the B. cereus group phages, from their discovery to their modern biotechnological applications. A special focus is given to phages inf...

  5. Fluorescent Amplified Fragment Length Polymorphism Analysis of Bacillus anthracis, Bacillus cereus, and Bacillus thuringiensis Isolates

    OpenAIRE

    Hill, Karen K.; Ticknor, Lawrence O.; Okinaka, Richard T.; Asay, Michelle; Blair, Heather; Bliss, Katherine A.; Laker, Mariam; Pardington, Paige E.; Richardson, Amber P.; Tonks, Melinda; Beecher, Douglas J.; Kemp, John D.; Kolstø, Anne-Brit; Wong, Amy C. Lee; Keim, Paul

    2004-01-01

    DNA from over 300 Bacillus thuringiensis, Bacillus cereus, and Bacillus anthracis isolates was analyzed by fluorescent amplified fragment length polymorphism (AFLP). B. thuringiensis and B. cereus isolates were from diverse sources and locations, including soil, clinical isolates and food products causing diarrheal and emetic outbreaks, and type strains from the American Type Culture Collection, and over 200 B. thuringiensis isolates representing 36 serovars or subspecies were from the U.S. D...

  6. Bacteriophage PBC1 and its endolysin as an antimicrobial agent against Bacillus cereus.

    Science.gov (United States)

    Kong, Minsuk; Ryu, Sangryeol

    2015-04-01

    Bacillus cereus is an opportunistic human pathogen responsible for food poisoning and other, nongastrointestinal infections. Due to the emergence of multidrug-resistant B. cereus strains, the demand for alternative therapeutic options is increasing. To address these problems, we isolated and characterized a Siphoviridae virulent phage, PBC1, and its lytic enzymes. PBC1 showed a very narrow host range, infecting only 1 of 22 B. cereus strains. Phylogenetic analysis based on the major capsid protein revealed that PBC1 is more closely related to the Bacillus clarkii phage BCJA1c and phages of lactic acid bacteria than to the phages infecting B. cereus. Whole-genome comparison showed that the late-gene region, including the terminase gene, structural genes, and holin gene of PBC1, is similar to that from B. cereus temperate phage 250, whereas their endolysins are different. Compared to the extreme host specificity of PBC1, its endolysin, LysPBC1, showed a much broader lytic spectrum, albeit limited to the genus Bacillus. The catalytic domain of LysPBC1 when expressed alone also showed Bacillus-specific lytic activity, which was lower against the B. cereus group but higher against the Bacillus subtilis group than the full-length protein. Taken together, these results suggest that the virulent phage PBC1 is a useful component of a phage cocktail to control B. cereus, even with its exceptionally narrow host range, as it can kill a strain of B. cereus that is not killed by other phages, and that LysPBC1 is an alternative biocontrol agent against B. cereus. PMID:25595773

  7. The Pathogenomic Sequence Analysis of B. cereus and B.thuringiensis Isolates Closely Related to Bacillus anthracis

    Energy Technology Data Exchange (ETDEWEB)

    Han, Cliff S.; Xie, Gary; Challacombe, Jean F.; Altherr, MichaelR.; Smriti, B.; Bruce, David; Campbell, Connie S.; Campbell, Mary L.; Chen, Jin; Chertkov, Olga; Cleland, Cathy; Dimitrijevic-Bussod, M.; Doggett, Norman A.; Fawcett, John J.; Glavina, Tijana; Goodwin, Lynne A.; Hill, Karen K.; Hitchcock, Penny; Jackson, Paul J.; Keim, Paul; Kewalramani, Avinash Ramesh; Longmire, Jon; Lucas, Susan; Malfatti,Stephanie; McMurry, Kim; Meincke, Linda J.; Misra, Monica; Moseman,Bernice L.; Mundt, Mark; Munk, A. Christine; Okinaka, Richard T.; Parson-Quintana, B.; Reilly, Lee P.; Richardson, Paul; Robinson, DonnaL.; Rubin, Eddy; Saunders, Elizabeth; Tapia, Roxanne; Tesmer, Judith G.; Thayer, Nina; Thompson, Linda S.; Tice, Hope; Ticknor, Lawrence O.; Wills, Patti L.; Gilna, Payl; Brettin, Thomas S.

    2005-08-18

    The sequencing and analysis of two close relatives of Bacillus anthracis are reported. AFLP analysis of over 300 isolates of B.cereus, B. thuringiensis and B. anthracis identified two isolates as being very closely related to B. anthracis. One, a B. cereus, BcE33L, was isolated from a zebra carcass in Nambia; the second, a B. thuringiensis, 97-27, was isolated from a necrotic human wound. The B. cereus appears to be the closest anthracis relative sequenced to date. A core genome of over 3,900 genes was compiled for the Bacillus cereus group, including Banthracis. Comparative analysis of these two genomes with other members of the B. cereus group provides insight into the evolutionary relationships among these organisms. Evidence is presented that differential regulation modulates virulence, rather than simple acquisition of virulence factors. These genome sequences provide insight into the molecular mechanisms contributing to the host range and virulence of this group of organisms.

  8. Occurrence of Toxigenic Bacillus cereus and Bacillus thuringiensis in Doenjang, a Korean Fermented Soybean Paste.

    Science.gov (United States)

    Park, Kyung Min; Kim, Hyun Jung; Jeong, Moon Cheol; Koo, Minseon

    2016-04-01

    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. PMID:27052865

  9. Cereulide synthetase gene cluster from emetic Bacillus cereus: Structure and location on a mega virulence plasmid related to Bacillus anthracis toxin plasmid pXO1

    Directory of Open Access Journals (Sweden)

    Wagner Martin

    2006-03-01

    Full Text Available Abstract Background Cereulide, a depsipeptide structurally related to valinomycin, is responsible for the emetic type of gastrointestinal disease caused by Bacillus cereus. Recently, it has been shown that this toxin is produced by a nonribosomal peptide synthetase (NRPS, but its exact genetic organization and biochemical synthesis is unknown. Results The complete sequence of the cereulide synthetase (ces gene cluster, which encodes the enzymatic machinery required for the biosynthesis of cereulide, was dissected. The 24 kb ces gene cluster comprises 7 CDSs and includes, besides the typical NRPS genes like a phosphopantetheinyl transferase and two CDSs encoding enzyme modules for the activation and incorporation of monomers in the growing peptide chain, a CDS encoding a putative hydrolase in the upstream region and an ABC transporter in the downstream part. The enzyme modules responsible for incorporation of the hydroxyl acids showed an unusual structure while the modules responsible for the activation of the amino acids Ala and Val showed the typical domain organization of NRPS. The ces gene locus is flanked by genetic regions with high homology to virulence plasmids of B. cereus, Bacillus thuringiensis and Bacillus anthracis. PFGE and Southern hybridization showed that the ces genes are restricted to emetic B. cereus and indeed located on a 208 kb megaplasmid, which has high similarities to pXO1-like plasmids. Conclusion The ces gene cluster that is located on a pXO1-like virulence plasmid represents, beside the insecticidal and the anthrax toxins, a third type of B. cereus group toxins encoded on megaplasmids. The ces genes are restricted to emetic toxin producers, but pXO1-like plasmids are also present in emetic-like strains. These data might indicate the presence of an ancient plasmid in B. cereus which has acquired different virulence genes over time. Due to the unusual structure of the hydroxyl acid incorporating enzyme modules of Ces

  10. The Silicon Layer Supports Acid Resistance of Bacillus cereus Spores

    OpenAIRE

    Hirota, Ryuichi; Hata, Yumehiro; Ikeda, Takeshi; Ishida, Takenori; Kuroda, Akio

    2010-01-01

    Silicon (Si) is considered to be a “quasiessential” element for most living organisms. However, silicate uptake in bacteria and its physiological functions have remained obscure. We observed that Si is deposited in a spore coat layer of nanometer-sized particles in Bacillus cereus and that the Si layer enhances acid resistance. The novel acid resistance of the spore mediated by Si encapsulation was also observed in other Bacillus strains, representing a general adaptation enhancing survival u...

  11. Genome Differences That Distinguish Bacillus anthracis from Bacillus cereus and Bacillus thuringiensis

    OpenAIRE

    Radnedge, Lyndsay; Agron, Peter G.; Hill, Karen K.; Jackson, Paul J.; Ticknor, Lawrence O; Keim, Paul; Andersen, Gary L.

    2003-01-01

    The three species of the group 1 bacilli, Bacillus anthracis, B. cereus, and B. thuringiensis, are genetically very closely related. All inhabit soil habitats but exhibit different phenotypes. B. anthracis is the causative agent of anthrax and is phylogenetically monomorphic, while B. cereus and B. thuringiensis are genetically more diverse. An amplified fragment length polymorphism analysis described here demonstrates genetic diversity among a collection of non-anthrax-causing Bacillus speci...

  12. Critical groups vs. representative person: dose calculations due to predicted releases from USEXA

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, N.L.D., E-mail: nelson.luiz@ctmsp.mar.mil.br [Centro Tecnologico da Marinha (CTM/SP), Sao Paulo, SP (Brazil); Rochedo, E.R.R., E-mail: elainerochedo@gmail.com [Instituto de Radiprotecao e Dosimetria (lRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Mazzilli, B.P., E-mail: mazzilli@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    The critical group cf Centro Experimental Aramar (CEA) site was previously defined based 00 the effluents releases to the environment resulting from the facilities already operational at CEA. In this work, effective doses are calculated to members of the critical group considering the predicted potential uranium releases from the Uranium Hexafluoride Production Plant (USEXA). Basically, this work studies the behavior of the resulting doses related to the type of habit data used in the analysis and two distinct situations are considered: (a) the utilization of average values obtained from official institutions (IBGE, IEA-SP, CNEN, IAEA) and from the literature; and (b) the utilization of the 95{sup tb} percentile of the values derived from distributions fit to the obtained habit data. The first option corresponds to the way that data was used for the definition of the critical group of CEA done in former assessments, while the second one corresponds to the use of data in deterministic assessments, as recommended by ICRP to estimate doses to the so--called 'representative person' . (author)

  13. Critical groups vs. representative person: dose calculations due to predicted releases from USEXA

    International Nuclear Information System (INIS)

    The critical group cf Centro Experimental Aramar (CEA) site was previously defined based 00 the effluents releases to the environment resulting from the facilities already operational at CEA. In this work, effective doses are calculated to members of the critical group considering the predicted potential uranium releases from the Uranium Hexafluoride Production Plant (USEXA). Basically, this work studies the behavior of the resulting doses related to the type of habit data used in the analysis and two distinct situations are considered: (a) the utilization of average values obtained from official institutions (IBGE, IEA-SP, CNEN, IAEA) and from the literature; and (b) the utilization of the 95tb percentile of the values derived from distributions fit to the obtained habit data. The first option corresponds to the way that data was used for the definition of the critical group of CEA done in former assessments, while the second one corresponds to the use of data in deterministic assessments, as recommended by ICRP to estimate doses to the so--called 'representative person' . (author)

  14. Comparison of Bacillus thuringiensis and Bacillus cereus

    International Nuclear Information System (INIS)

    Bacillus cereus and Bacillus thuringiensis are closely related, spore forming soil bacteria. B. thuringiensis produces insecticidal crystal proteins during sporulation and these toxins are the most important biopesticides in the world today. Genomes of the B. thuringiensis and B. cereus strains were analysed by pulsed field gel electrophoresis after treatment of the DNA with the restriction enzyme NotI. The NotI fingerprint patterns varied both within the B. thuringiensis and the B. cereus strains. The size of the fragments varied between 15 and 1350 kb. When physical maps of the B. thuringiensis and B. cereus strains were compared, B. thuringiensis appeared to be as closely related to B. cereus as the B. cereus strains were to each other. Nine out of 12 B. thuringiensis strains and 18 out of 25 B. cereus strains produced enterotoxins. The close relationship between B. thuringiensis and B. cereus should be taken into consideration when B. thuringiensis is used as a biopesticide. (author). 10 refs, 4 figs, 1 tab

  15. Under-represented students' engagement in secondary science learning: A non-equivalent control group design

    Science.gov (United States)

    Vann-Hamilton, Joy J.

    Problem. A significant segment of the U.S. population, under-represented students, is under-engaged or disengaged in secondary science education. International and national assessments and various research studies illuminate the problem and/or the disparity between students' aspirations in science and the means they have to achieve them. To improve engagement and address inequities among these students, more contemporary and/or inclusive pedagogy is recommended. More specifically, multicultural science education has been suggested as a potential strategy for increased equity so that all learners have access to and are readily engaged in quality science education. While multicultural science education emphasizes the integration of students' backgrounds and experiences with science learning , multimedia has been suggested as a way to integrate the fundamentals of multicultural education into learning for increased engagement. In addition, individual characteristics such as race, sex, academic track and grades were considered. Therefore, this study examined the impact of multicultural science education, multimedia, and individual characteristics on under-represented students' engagement in secondary science. Method. The Under-represented Students Engagement in Science Survey (USESS), an adaptation of the High School Survey of Student Engagement, was used with 76 high-school participants. The USESS was used to collect pretest and posttest data concerning their types and levels of student engagement. Levels of engagement were measured with Strongly Agree ranked as 5, down to Strongly Disagree ranked at 1. Participants provided this feedback prior to and after having interacted with either the multicultural or the non-multicultural version of the multimedia science curriculum. Descriptive statistics for the study's participants and the survey items, as well as Cronbach's alpha coefficient for internal consistency reliability with respect to the survey subscales, were

  16. COLONIZATION OF VIGNA RADIATA ROOTS BY CHROMIUM RESISTANT BACTERIAL STRAINS OF OCHROBACTRUM INTERMEDIUM, BACILLUS CEREUS AND BREVIBA CTERIUM SP.

    Institute of Scientific and Technical Information of China (English)

    MUHAMMAD Faisal; SHAHIDA Hasnain

    2005-01-01

    The present study deals with colonization potential of plant growth promoting bacterial strains ( Ochrobactrum intermedium, Bacillus cereus and Brevibacterium sp. ) on Vigna radiata roots. The roots were heavily colonized with O. intermedium and B. cereus as compared to Brevibacterium sp. O. intermedium mainly colonized rhizoplane while B. cereus occurred both on the rhizoplane and near root zone. O. intermedium and B. cereus were found to be present both on the rhizoplane and near root zone, while Brevibacterium only in the rhizosphere in the form of groups. The cells of B. cereus were found more in the sites where root exudates were existed. From the above results it was observed that the number of O. intermedium cells were large at root exudate site. Fig 2, Tab 1, Ref 15

  17. Characterization of Bacillus cereus isolates from local dairy farms in China.

    Science.gov (United States)

    Cui, Yifang; Liu, Xiaoye; Dietrich, Richard; Märtlbauer, Erwin; Cao, Jie; Ding, Shuangyang; Zhu, Kui

    2016-06-01

    Bacillus cereus is an important opportunistic foodborne pathogen. In the present work, a total of 306 milk and environmental samples were collected from 10 local dairy farms in Beijing, China. Of the 92 B. cereus-like isolates, 88 and 4 belonged to B. cereus and B. thuringiensis, respectively. The prevalence of B. cereus isolates in bedding, feces, feed, liquid manure and raw milk was 93.3%, 78.9%, 41.2%, 100.0% and 9.8%, respectively. Three main toxin genes nhe, hbl and ces were detected with rates of 100.0%, 78.3% and 1.1%, but no strain harbored cytK1 The production of Nhe, Hbl and cereulide could be confirmed by specific monoclonal antibodies-based enzyme immunoassays in 94.6%, 70.7% and 1.1% of all isolates, respectively. Cytotoxicity tests were used to further corroborate the results of genetic and protein-based assays; 91.3% of the isolates showed cytotoxicity to Vero cells. All isolates were tested for antimicrobial resistance against 17 antibiotics. All isolates were resistant to lincomycin, retapamulin, tiamulin and valnemulin, while two strains were susceptible to ampicillin and ceftiofur. A total of 16 isolated strains were resistant to tetracycline. Since spores of B. cereus are not inactivated during manufacturing of most milk products, contamination of milk with B. cereus on the farm level may represent a potential hazard, particularly with respect to emetic toxin-producing strains. PMID:27190168

  18. Isolation and characterisation of Bacillus cereus from pasteurised milk in household refrigerators in The Netherlands.

    Science.gov (United States)

    Te Giffel, M C; Beumer, R R; Granum, P E; Rombouts, F M

    1997-03-01

    The incidence and some characteristics (carbohydrate metabolism, growth profiles, haemolysin production and enterotoxin production) of Bacillus cereus, in pasteurised, low-fat (1.5%) milk, in household refrigerators in the Netherlands was investigated. In 247 (74%) of the 334 milk samples analyzed, the mesophilic aerobic counts were between 50 and 5000 per millilitre. B. cereus could be isolated from 133 (40%) of the samples. In general the B. cereus counts were low; numbers of less than five per millilitre were observed in 258 (77%) of the samples. As expected, both the mesophilic aerobic counts and levels of B. cereus increased with increasing storage temperatures in the refrigerator and prolonged storage times. In total, 143 presumptive B. cereus colonies were isolated. According to the ISO confirmation tests and the carbohydrate patterns (API 50 CHB) 134 (94%) of these isolates were confirmed to be B. cereus. Of these 134 isolates 20% fermented lactose and 53% of the 106 strains tested were able to grow at 7 degrees C. These percentages are much higher than expected for strains isolated from non-dairy products, suggesting that strains can adapt to environmental conditions in milk. All 106 strains tested, produced haemolysin, 27% showed the discontinuous haemolytic pattern characteristic for haemolysin BL, possibly a virulence factor. Of the 37 B. cereus isolates tested for enterotoxin production 27 (73%), 28 (76%) and 26 (70%) were found to be enterotoxigenic (as determined by the Western immunoblot technique, polymerase chain reaction (PCR) and Vero cell assays, respectively). Isolates unable to ferment lactose, produced less enterotoxin in comparison with those able to utilize lactose. Although only a few outbreaks of food poisoning caused by B. cereus in milk (products) have been reported, most strains isolated from these products are able to produce enterotoxins and may represent a health hazard. PMID:9039575

  19. The Pore-Forming Haemolysins of Bacillus Cereus: A Review

    OpenAIRE

    Vincent Sanchis; Nalini Ramarao

    2013-01-01

    The Bacillus cereus sensu lato group contains diverse Gram-positive spore-forming bacteria that can cause gastrointestinal diseases and severe eye infections in humans. They have also been incriminated in a multitude of other severe, and frequently fatal, clinical infections, such as osteomyelitis, septicaemia, pneumonia, liver abscess and meningitis, particularly in immuno-compromised patients and preterm neonates. The pathogenic properties of this organism are mediated by the synergistic ef...

  20. The Pore-Forming Haemolysins of Bacillus Cereus: A Review

    Directory of Open Access Journals (Sweden)

    Vincent Sanchis

    2013-06-01

    Full Text Available The Bacillus cereus sensu lato group contains diverse Gram-positive spore-forming bacteria that can cause gastrointestinal diseases and severe eye infections in humans. They have also been incriminated in a multitude of other severe, and frequently fatal, clinical infections, such as osteomyelitis, septicaemia, pneumonia, liver abscess and meningitis, particularly in immuno-compromised patients and preterm neonates. The pathogenic properties of this organism are mediated by the synergistic effects of a number of virulence products that promote intestinal cell destruction and/or resistance to the host immune system. This review focuses on the pore-forming haemolysins produced by B. cereus: haemolysin I (cereolysin O, haemolysin II, haemolysin III and haemolysin IV (CytK. Haemolysin I belongs to the cholesterol-dependent cytolysin (CDC family whose best known members are listeriolysin O and perfringolysin O, produced by L. monocytogenes and C. perfringens respectively. HlyII and CytK are oligomeric ß-barrel pore-forming toxins related to the α-toxin of S. aureus or the ß-toxin of C. perfringens. The structure of haemolysin III, the least characterized haemolytic toxin from the B. cereus, group has not yet been determined.

  1. The pore-forming haemolysins of bacillus cereus: a review.

    Science.gov (United States)

    Ramarao, Nalini; Sanchis, Vincent

    2013-06-01

    The Bacillus cereus sensu lato group contains diverse Gram-positive spore-forming bacteria that can cause gastrointestinal diseases and severe eye infections in humans. They have also been incriminated in a multitude of other severe, and frequently fatal, clinical infections, such as osteomyelitis, septicaemia, pneumonia, liver abscess and meningitis, particularly in immuno-compromised patients and preterm neonates. The pathogenic properties of this organism are mediated by the synergistic effects of a number of virulence products that promote intestinal cell destruction and/or resistance to the host immune system. This review focuses on the pore-forming haemolysins produced by B. cereus: haemolysin I (cereolysin O), haemolysin II, haemolysin III and haemolysin IV (CytK). Haemolysin I belongs to the cholesterol-dependent cytolysin (CDC) family whose best known members are listeriolysin O and perfringolysin O, produced by L. monocytogenes and C. perfringens respectively. HlyII and CytK are oligomeric ß-barrel pore-forming toxins related to the α-toxin of S. aureus or the ß-toxin of C. perfringens. The structure of haemolysin III, the least characterized haemolytic toxin from the B. cereus, group has not yet been determined. PMID:23748204

  2. Microbial Transformation of Quercetin by Bacillus cereus

    OpenAIRE

    Rao, Koppaka V.; Weisner, Nghe T.

    1981-01-01

    Biotransformation of quercetin was examined with a number of bacterial cultures. In the presence of a bacterial culture (Bacillus cereus), quercetin was transformed into two crystalline products, identified as protocatechuic acid and quercetin-3-glucoside (isoquercitrin).

  3. Bacillus cereus as a nongastrointestinal pathogen

    OpenAIRE

    Pavani G.

    2014-01-01

    The potential of Bacillus cereus to cause systemic infections is of serious concern. Apart from Gastrointestinal infections, it causes respiratory tract infections, nosocomial infections, eye infections, CNS infections, cutaneous infections, endocarditis, osteomyelitis and urinary tract infections. The potential of this bacterium to cause life threatening infections has increased. Trauma is an important predisposing factor for Bacillus cereus infections. The maintenance of skin and mucous mem...

  4. Bacillus cereus, a volatile human pathogen.

    Science.gov (United States)

    Bottone, Edward J

    2010-04-01

    Bacillus cereus is a Gram-positive aerobic or facultatively anaerobic, motile, spore-forming, rod-shaped bacterium that is widely distributed environmentally. While B. cereus is associated mainly with food poisoning, it is being increasingly reported to be a cause of serious and potentially fatal non-gastrointestinal-tract infections. The pathogenicity of B. cereus, whether intestinal or nonintestinal, is intimately associated with the production of tissue-destructive exoenzymes. Among these secreted toxins are four hemolysins, three distinct phospholipases, an emesis-inducing toxin, and proteases. The major hurdle in evaluating B. cereus when isolated from a clinical specimen is overcoming its stigma as an insignificant contaminant. Outside its notoriety in association with food poisoning and severe eye infections, this bacterium has been incriminated in a multitude of other clinical conditions such as anthrax-like progressive pneumonia, fulminant sepsis, and devastating central nervous system infections, particularly in immunosuppressed individuals, intravenous drug abusers, and neonates. Its role in nosocomial acquired bacteremia and wound infections in postsurgical patients has also been well defined, especially when intravascular devices such as catheters are inserted. Primary cutaneous infections mimicking clostridial gas gangrene induced subsequent to trauma have also been well documented. B. cereus produces a potent beta-lactamase conferring marked resistance to beta-lactam antibiotics. Antimicrobials noted to be effective in the empirical management of a B. cereus infection while awaiting antimicrobial susceptibility results for the isolate include ciprofloxacin and vancomycin. PMID:20375358

  5. Surface reaction of Bacillus cereus biomass and its biosorption for lead and copper ions

    Institute of Scientific and Technical Information of China (English)

    PAN Jian-hua; LIU Rui-xia; TANG Hong-xiao

    2007-01-01

    In this study, the Fourier transform infrared (FTIR) analytical technique identified the surface chemical functional groups of Bacillus cereus biomass. B. Cereus cells mainly contained carboxyl, hydroxyl, phosphate, amino, and amide functional groups. In order to explain the surface acid-base properties of aqueous B. Cereus biomass, the potentiometric titration was conducted . The computer program FITEQL 4.0 was used to perform the model calculations. The optimization results indicated that three sites-three pKas model, which assumed the cell surface to have three distinct types of surface organic functional groups based on IR analysis results, simulated the experimental results very well. Moreover, batch adsorption experiments were performed to investigate biosorption behavior of Cu (Ⅱ) and Pb (Ⅱ) ions onto the biomass. Obviously, the adsorption equilibrium data for the two ions were reasonably described by typical Langmuir isotherm.

  6. Genetic Differentiation between Sympatric Populations of Bacillus cereus and Bacillus thuringiensis

    Science.gov (United States)

    Vilas-Boas, Gislayne; Sanchis, Vincent; Lereclus, Didier; Lemos, Manoel Victor F.; Bourguet, Denis

    2002-01-01

    Little is known about genetic exchanges in natural populations of bacteria of the spore-forming Bacillus cereus group, because no population genetics studies have been performed with local sympatric populations. We isolated strains of Bacillus thuringiensis and B. cereus from small samples of soil collected at the same time from two separate geographical sites, one within the forest and the other at the edge of the forest. A total of 100 B. cereus and 98 B. thuringiensis strains were isolated and characterized by electrophoresis to determine allelic composition at nine enzymatic loci. We observed genetic differentiation between populations of B. cereus and B. thuringiensis. Populations of a given Bacillus species—B. thuringiensis or B. cereus—were genetically more similar to each other than to populations of the other Bacillus species. Hemolytic activity provided further evidence of this genetic divergence, which remained evident even if putative clones were removed from the data set. Our results suggest that the rate of gene flow was higher between strains of the same species, but that exchanges between B. cereus and B. thuringiensis were nonetheless possible. Linkage disequilibrium analysis revealed sufficient recombination for B. cereus populations to be considered panmictic units. In B. thuringiensis, the balance between clonal proliferation and recombination seemed to depend on location. Overall, our data indicate that it is not important for risk assessment purposes to determine whether B. cereus and B. thuringiensis belong to a single or two species. Assessment of the biosafety of pest control based on B. thuringiensis requires evaluation of the extent of genetic exchange between strains in realistic natural conditions. PMID:11872495

  7. Elucidation of enterotoxigenic Bacillus cereus outbreaks in Austria by complementary epidemiological and microbiological investigations, 2013.

    Science.gov (United States)

    Schmid, Daniela; Rademacher, Corinna; Kanitz, Elisabeth Eva; Frenzel, Elrike; Simons, Erica; Allerberger, Franz; Ehling-Schulz, Monika

    2016-09-01

    Identifying Bacillus cereus as the causative agent of a foodborne outbreak still poses a challenge. We report on the epidemiological and microbiological investigation of three outbreaks of food poisoning (A, B, and C) in Austria in 2013. A total of 44% among 32 hotel guests (A), 22% among 63 employees (B) and 29% among 362 residents of a rehab clinic (C) fell sick immediately after meal consumption. B. cereus isolated from left overs or retained samples from related foods were characterized by toxin gene profiling, and molecular typing using panC sequencing and M13-PCR typing (in outbreak A and C). We identified two B. cereus strains in outbreak A, and six B. cereus strains, each in outbreak B and C; we also found Staphylococcus aureus and staphylococcal enterotoxins in outbreak A. The panC sequence based phylogenetic affiliation of the B. cereus strains, together with findings of the retrospective cohort analyses, helped determining their etiological role. Consumption of a mashed potatoes dish in outbreak A (RR: ∞), a pancake strips soup in outbreak B (RR 13.0; 95% CI 1.8-93.0) and for outbreak C of a fruit salad (RR 1.50; 95% CI 1.09-2.00), deer ragout (RR: 1.99; 95% CI 1.23-3.22) and a cranberry/pear (RR 2.46; 95% CI 1.50-4.03)were associated with increased risk of falling sick. An enterotoxigenic strain affiliated to the phylogenetic group with the highest risk of food poisoning was isolated from the crème spinach and the strawberry buttermilk, and also from the stool samples of the one B. cereus positive outbreak case-patient, who ate both. Our investigation of three food poisoning outbreaks illustrates the added value of a combined approach by using epidemiological, microbiological and genotyping methods in identifying the likely outbreak sources and the etiological B. cereus strains. PMID:27257745

  8. Phages preying on Bacillus anthracis, Bacillus cereus, and Bacillus thuringiensis: past, present and future.

    Science.gov (United States)

    Gillis, Annika; Mahillon, Jacques

    2014-07-01

    Many bacteriophages (phages) have been widely studied due to their major role in virulence evolution of bacterial pathogens. However, less attention has been paid to phages preying on bacteria from the Bacillus cereus group and their contribution to the bacterial genetic pool has been disregarded. Therefore, this review brings together the main information for the B. cereus group phages, from their discovery to their modern biotechnological applications. A special focus is given to phages infecting Bacillus anthracis, B. cereus and Bacillus thuringiensis. These phages belong to the Myoviridae, Siphoviridae, Podoviridae and Tectiviridae families. For the sake of clarity, several phage categories have been made according to significant characteristics such as lifestyles and lysogenic states. The main categories comprise the transducing phages, phages with a chromosomal or plasmidial prophage state, γ-like phages and jumbo-phages. The current genomic characterization of some of these phages is also addressed throughout this work and some promising applications are discussed here. PMID:25010767

  9. Phages Preying on Bacillus anthracis, Bacillus cereus, and Bacillus thuringiensis: Past, Present and Future

    Directory of Open Access Journals (Sweden)

    Annika Gillis

    2014-07-01

    Full Text Available Many bacteriophages (phages have been widely studied due to their major role in virulence evolution of bacterial pathogens. However, less attention has been paid to phages preying on bacteria from the Bacillus cereus group and their contribution to the bacterial genetic pool has been disregarded. Therefore, this review brings together the main information for the B. cereus group phages, from their discovery to their modern biotechnological applications. A special focus is given to phages infecting Bacillus anthracis, B. cereus and Bacillus thuringiensis. These phages belong to the Myoviridae, Siphoviridae, Podoviridae and Tectiviridae families. For the sake of clarity, several phage categories have been made according to significant characteristics such as lifestyles and lysogenic states. The main categories comprise the transducing phages, phages with a chromosomal or plasmidial prophage state, γ-like phages and jumbo-phages. The current genomic characterization of some of these phages is also addressed throughout this work and some promising applications are discussed here.

  10. Representing collective reasons for group decisions: The judgment aggregation problem revisited

    OpenAIRE

    Andrew Knops

    2011-01-01

    This article argues that the discursive dilemma and the judgement aggregation which causes it are based on a misconception of what it means for a group to give reasons for a democratic decision. Judgement aggregation analyses fail to distinguish between the procedure for determining such a decision, which should involve a vote of all group members, and the process for determining the reasons for such a decision, which should only take account of the views of the members that supported that de...

  11. Siderophore-mediated iron acquisition systems in Bacillus cereus: identification of receptors for anthrax virulence-associated petrobactin†a

    OpenAIRE

    Zawadzka, Anna M.; Abergel, Rebecca J.; Nichiporuk, Rita; Andersen, Ulla N.; Raymond, Kenneth N.

    2009-01-01

    During growth under iron limitation, Bacillus cereus and Bacillus anthracis, two human pathogens from the Bacillus cereus group of Gram-positive bacteria, secrete two siderophores, bacillibactin (BB) and petrobactin (PB), for iron acquisition via membrane-associated substrate-binding proteins (SBPs) and other ABC transporter components. Since PB is associated with virulence traits in B. anthracis, the PB-mediated iron uptake system presents a potential target for antimicrobial therapies; its ...

  12. Yersinia ruckeri biotype 2 isolates from mainland Europe and the UK likely represent different clonal groups

    DEFF Research Database (Denmark)

    Wheeler, Richard W.; Davies, Robert L.; Dalsgaard, Inger;

    2009-01-01

    likely origins and relationships, a geographically and temporally diverse collection of isolates were characterised by serotyping, biotyping, pulsed-field gel electrophoresis (PFGE) and outer membrane protein (OMP) profiling. A total of 44 pulsotypes were identified from 160 isolates by PFGE, using the...... different pulsotypes, suggesting that they represented different clones that may have emerged separately. Danish biotype 2 isolates recovered since 1995 were indistinguishable by PFGE from the dominant biotype 1 clone responsible for the majority of outbreaks in Denmark and the rest of mainland Europe. In...

  13. Proteome data to explore the impact of pBClin15 on Bacillus cereus ATCC 14579.

    Science.gov (United States)

    Madeira, Jean-Paul; Alpha-Bazin, Béatrice; Armengaud, Jean; Omer, Hélène; Duport, Catherine

    2016-09-01

    This data article reports changes in the cellular and exoproteome of B. cereus cured from pBClin15.Time-course changes of proteins were assessed by high-throughput nanoLC-MS/MS. We report all the peptides and proteins identified and quantified in B. cereus with and without pBClin15. Proteins were classified into functional groups using the information available in the KEGG classification and we reported their abundance in term of normalized spectral abundance factor. The repertoire of experimentally confirmed proteins of B. cereus presented here is the largest ever reported, and provides new insights into the interplay between pBClin15 and its host B. cereus ATCC 14579. The data reported here is related to a published shotgun proteomics analysis regarding the role of pBClin15, "Deciphering the interactions between the Bacillus cereus linear plasmid, pBClin15, and its host by high-throughput comparative proteomics" Madeira et al. [1]. All the associated mass spectrometry data have been deposited in the ProteomeXchange Consortium (http://proteomecentral.proteomexchange.org) via the PRIDE partner repository (http://www.ebi.ac.uk/pride/), with the dataset identifier PRIDE: PXD001568, PRIDE: PXD002788 and PRIDE: PXD002789. PMID:27547804

  14. Diagnostic properties of three conventional selective plating media for selection of Bacillus cereus, B. thuringiensis and B. weihenstephanensis

    DEFF Research Database (Denmark)

    Hendriksen, Niels Bohse; Hansen, Bjarne Munk

    2011-01-01

    The aim of this study was to assess the diagnostic properties of the two selective plating media and a chromogenic medium for identification of Bacillus cereus. The 324 isolates were B. cereus (37%), Bacillus weihenstephanensis (45%) or Bacillus thuringiensis (18%), as identified by a new...... combination of techniques. All isolates were growing on mannitol–egg yolk–polymyxin agar (MYP), and they did not form acid from mannitol. However, a significant lower number of B. thuringiensis isolates did not show lecithinase activity. All isolates were also growing on polymyxin–egg yolk...... recommended selective plating media MYP and PEMBA for detection of B. cereus group bacteria both have their limitations for identification of some B. cereus, B. weihenstephanensis or B. thuringiensis. However, MYP is preferable compared to PEMBA. The chromogenic medium has its own advantages and limitations...

  15. Obesity in occupational groups of Western Siberia: comparison with representative national data

    Directory of Open Access Journals (Sweden)

    S A Maksimov

    2013-03-01

    Full Text Available The aim of this study was to compare obesity prevalences in the occupational groups of Western Siberia with the national data. Materials and methods: We performed a single-step cross-sectional study enrolling 4472 employees of 14 occupational groups from Western Siberian institutions and enterprises. Obesity was considered to be present if the body mass index was >30.0 kg/m2; sex, age and education data were obtained with questionnaires. Age-adjusted obesity prevalence in the occupational groups (separately for men and women was compared with the national data with calculation of odds ratio, attributable risk and 95% confidence interval. Results: Among women the prevalence of obesity was lower in teachers compared with the national data (OR=0.45; 95% CI: 0.31–0.66. Higher obesity prevalence was observed among operating personnel and technical workers (OR=1.69; 95% CI: 1.37–2.09 as well as metallurgy equipment operators (OR=1.65; 95% CI: 1.17–2.31. Among males higher obesity prevalence was registered in top-managers (OR=2.53; 95% CI: 1.80–3.55, operating personnel and technical workers (OR=2.03; 95% CI: 1.59–2.58, civil servants (OR=1.75; 95% CI: 1.27–2.40, and mechanics (OR=1.37; 95% CI: 1.08–1.73. Moreover, in women university education (higher percentage of employees having graduated from a higher professional institution led to less obesity prevalence. In males no such tendencies were observed. Conclusions: The study allowed to identify the occupational groups of Western Siberia with higher obesity prevalence and to demonstrate the impact of sex and education level on this parameter. The obtained data can make a theoretical and practical basis for primary and secondary prevention of obesity in the workplace.

  16. 19. working group meeting of representatives of RCA member States. Report

    International Nuclear Information System (INIS)

    The 19. RCA Working Group Meeting was hosted by the Myanmar Atomic Energy Committee in Yangon from 10-14 March 1997. The meeting marked the 25. anniversary of the RCA which commenced in 1972. It was attended by 29 delegates from 15 visiting RCA Member States, 15 participants from Myanmar and 4 from the IAEA. The report contains the statements of the following countries: Australia, Bangladesh, China, India, Indonesia, Japan, Republic of Korea, Malaysia, Mongolia, Myanmar, New Zealand, Pakistan, Philippines, Singapore, Sri Lanka, Thailand, and Viet Nam. Tabs

  17. Key environmental challenges for food groups and regions representing the variation within the EU, Ch.3 Salmon Aquaculture Supply Chain

    DEFF Research Database (Denmark)

    G., Ólafsdóttir; Andrade, Grace Patricia Viera; Nielsen, Thorkild;

    2013-01-01

    The report is aimed to give a thorough review of different environmental impacts that the food and drink sector are producing along the whole chain, from fork to farm and to assess which of them are the key environmental challenges for Europe. A representative range of product groups have been...

  18. Concurrent crack and powder cocaine users from Sao Paulo: Do they represent a different group?

    Directory of Open Access Journals (Sweden)

    Breen Gerome

    2006-01-01

    Full Text Available Abstract Background Cocaine abuse is a serious and socially damaging illegal drug problem. Different routes of administration are associated with a specific progression of use, different degrees of abuse liability, propensity for dependence and treatment response. There have been relatively few studies comparing different cocaine users groups and no studies into the characterization of the group of individuals reporting concurrent use of powder cocaine and crack cocaine. Methods Six hundred and ninety-nine cocaine users were assessed during the period August 1997 to October 1998 in one outpatient and six inpatient clinics located in the São Paulo, Brazil. Patients were interviewed using a structured questionnaire schedule in Portuguese, designed specifically for the Brazilian population. The statistical analyses were performed using either ANOVA or a chi-squared test and focusing on their preferred form of use/route of administration and other variables. Results For 83% of the variables tested in this study, the Dual Users subgroup (using both powder and crack cocaine demonstrated statistical differences from the single drug user subgroups. Those differences include the initiation of cocaine, the abuse of other illicit drugs, and rates of criminal history. Conclusion These data suggest cocaine-dependent individuals who report use of both powder and crack cocaine are an at least partially, distinct subgroup. However, further studies will be necessary to confirm this and to determine if they also show a different treatment response.

  19. Characterization of LysPBC4, a novel Bacillus cereus-specific endolysin of bacteriophage PBC4.

    Science.gov (United States)

    Na, Hongjun; Kong, Minsuk; Ryu, Sangryeol

    2016-06-01

    Bacillus cereus is a spore-forming, Gram-positive bacterium and is a major food-borne pathogen. A B. cereus-specific bacteriophage PBC4 was isolated from the soil of a stock farm, and its genome was analyzed. PBC4 belongs to the Siphoviridae family and has a genome consisting of 80 647-bp-long double-stranded DNA, including 123 genes and two tRNAs. LysPBC4, the endolysin of PBC4, has an enzymatically active domain (EAD) on its N-terminal region and a putative cell wall-binding domain (CBD) on its C-terminal region, respectively. Although the phage PBC4 showed a very limited host range, LysPBC4 could lyse all of the B. cereus strains tested. However, LysPBC4 did not kill other bacteria such as B. subtilis or Listeria, indicating that the endolysin has specific lytic activity against the B. cereus group species. Furthermore, LysPBC4_CBD fused with enhanced green fluorescent protein (EGFP) could decorate limited strains of B. cereus group, suggesting that the LysPBC4_CBD may be a promising material for specific detection of B. cereus. PMID:27190165

  20. Bacillus cereus Biofilms—Same, Only Different

    Science.gov (United States)

    Majed, Racha; Faille, Christine; Kallassy, Mireille; Gohar, Michel

    2016-01-01

    Bacillus cereus displays a high diversity of lifestyles and ecological niches and include beneficial as well as pathogenic strains. These strains are widespread in the environment, are found on inert as well as on living surfaces and contaminate persistently the production lines of the food industry. Biofilms are suspected to play a key role in this ubiquitous distribution and in this persistency. Indeed, B. cereus produces a variety of biofilms which differ in their architecture and mechanism of formation, possibly reflecting an adaptation to various environments. Depending on the strain, B. cereus has the ability to grow as immersed or floating biofilms, and to secrete within the biofilm a vast array of metabolites, surfactants, bacteriocins, enzymes, and toxins, all compounds susceptible to act on the biofilm itself and/or on its environment. Within the biofilm, B. cereus exists in different physiological states and is able to generate highly resistant and adhesive spores, which themselves will increase the resistance of the bacterium to antimicrobials or to cleaning procedures. Current researches show that, despite similarities with the regulation processes and effector molecules involved in the initiation and maturation of the extensively studied Bacillus subtilis biofilm, important differences exists between the two species. The present review summarizes the up to date knowledge on biofilms produced by B. cereus and by two closely related pathogens, Bacillus thuringiensis and Bacillus anthracis. Economic issues caused by B. cereus biofilms and management strategies implemented to control these biofilms are included in this review, which also discuss the ecological and functional roles of biofilms in the lifecycle of these bacterial species and explore future developments in this important research area. PMID:27458448

  1. Bacillus cereus as a nongastrointestinal pathogen

    Directory of Open Access Journals (Sweden)

    Pavani G.

    2014-02-01

    Full Text Available The potential of Bacillus cereus to cause systemic infections is of serious concern. Apart from Gastrointestinal infections, it causes respiratory tract infections, nosocomial infections, eye infections, CNS infections, cutaneous infections, endocarditis, osteomyelitis and urinary tract infections. The potential of this bacterium to cause life threatening infections has increased. Trauma is an important predisposing factor for Bacillus cereus infections. The maintenance of skin and mucous membrane integrity limits infection by this micro-organism. [Int J Res Med Sci 2014; 2(1.000: 28-30

  2. Features of Bacillus cereus swarm cells.

    Science.gov (United States)

    Senesi, Sonia; Salvetti, Sara; Celandroni, Francesco; Ghelardi, Emilia

    2010-11-01

    When propagated on solid surfaces, Bacillus cereus can produce differentiated swarm cells under a wide range of growth conditions. This behavioural versatility is ecologically relevant, since it allows this bacterium to adapt swarming to environmental changes. Swarming by B. cereus is medically important: swarm cells are more virulent and particularly prone to invade host tissues. Characterisation of swarming-deficient mutants highlights that flagellar genes as well as genes governing different metabolic pathways are involved in swarm-cell differentiation. In this review, the environmental and genetic requirements for swarming and the role played by swarm cells in the virulence this pathogen exerts will be outlined. PMID:21035546

  3. Transfer of Bacillus cereus spores from packaging paper into food.

    Science.gov (United States)

    Ekman, Jaakko; Tsitko, Irina; Weber, Assi; Nielsen-LeRoux, Christina; Lereclus, Didier; Salkinoja-Salonen, Mirja

    2009-11-01

    Food packaging papers are not sterile, as the manufacturing is an open process, and the raw materials contain bacteria. We modeled the potential transfer of the Bacillus cereus spores from packaging paper to food by using a green fluorescent protein-expressing construct of Bacillus thuringiensis Bt 407Cry(-) [pHT315Omega(papha3-gfp)], abbreviated BT-1. Paper (260 g m(-2)) containing BT-1 was manufactured with equipment that allowed fiber formation similar to that of full-scale manufactured paper. BT-1 adhered to pulp during papermaking and survived similar to an authentic B. cereus. Rice and chocolate were exposed to the BT-1-containing paper for 10 or 30 days at 40 or 20 degrees C at relative air humidity of 10 to 60%. The majority of the spores remained immobilized inside the fiber web; only 0.001 to 0.03% transferred to the foods. This amount is low compared with the process hygiene criteria and densities commonly found in food, and it does not endanger food safety. To measure this, we introduced BT-1 spores into the paper in densities of 100 to 1,000 times higher than the amounts of the B. cereus group bacteria found in commercial paper. Of BT-1 spores, 0.03 to 0.1% transferred from the paper to fresh agar surface within 5 min of contact, which is more than to food during 10 to 30 days of exposure. The findings indicate that transfer from paper to dry food is restricted to those microbes that are exposed on the paper surface and readily detectable with a contact agar method. PMID:19903384

  4. Physical map of the Bacillus cereus chromosome.

    OpenAIRE

    Kolstø, A B; Grønstad, A; Oppegaard, H

    1990-01-01

    A physical map of the Bacillus cereus chromosome has been constructed by aligning 11 NotI fragments, ranging in size from 200 to 1,300 kilobases. The size of the chromosome is about 5.7 megabases. This is the first Bacillus genome of which a complete physical map has been described.

  5. Effects of dietary Bacillus cereus G19, B. cereus BC-01, and Paracoccus marcusii DB11 supplementation on the growth, immune response, and expression of immune-related genes in coelomocytes and intestine of the sea cucumber (Apostichopus japonicus Selenka).

    Science.gov (United States)

    Yang, Gang; Tian, Xiangli; Dong, Shuanglin; Peng, Mo; Wang, Dongdong

    2015-08-01

    Probiotics have positive effects on the nutrient digestibility and absorption, immune responses, and growth of aquatic animals, including the sea cucumber (Apostichopus japonicus Selenka). A 60-day feeding trial was conducted to evaluate the effects of Bacillus cereus G19, B. cereus BC-01 and Paracoccus marcusii DB11 supplementation on the growth, immune response, and expression level of four immune-related genes (Aj-p105, Aj-p50, Aj-rel, and Aj-lys) in coelomocytes and the intestine of juvenile sea cucumbers. One group was fed the basal diet (control group), while three other groups were fed the basal diet supplemented with B. cereus G19 (G19 group), B. cereus BC-01 (BC group), or P. marcusii DB11 (PM group). The growth rate of sea cucumbers fed diets with probiotics supplementation was significantly higher than that of the control group (P < 0.05). Sea cucumbers in the G19 and PM groups had a significantly greater phagocytic activity of coelomocytes compared to the control group (P < 0.05), while those in the G19 and BC groups had a greater respiratory burst activity (P < 0.05). The alkaline phosphatase (AKP) activity of coelomocytes in sea cucumbers fed diets with probiotics supplementation was significantly higher than the control group (P < 0.05). Comparatively, superoxide dismutase (SOD) activity of coelomocytes for sea cucumber in the PM group was significantly greater (P < 0.05). As for the immune-related genes, B. cereus G19 supplementation significantly increased the expression level of the Aj-rel gene in coelomocytes (P < 0.05), while B. cereus BC-01 supplementation significantly increased that of the Aj-p50 gene as compared to the control group (P < 0.05). In the intestine, the relative expression level of Aj-p105, Aj-p50, and Aj-lys genes in the PM group was significantly higher than that in the control group (P < 0.05). These results suggested that B. cereus G19 and B. cereus BC-01 supplementation could improve the growth performance and the immune

  6. Purification, crystallization and preliminary X-ray characterization of Bacillus cereus arylamine N-­acetyltransferase 3 [(BACCR)NAT3

    OpenAIRE

    Kubiak, Xavier; Pluvinage, Benjamin; Li de la Sierra-Gallay, Inès; Weber, Patrick; Haouz, Ahmed; Dupret, Jean-Marie; Rodrigues-Lima, Fernando

    2012-01-01

    B. cereus arylamine N-acetyltransferase 3 was expressed, purified and crystallized. X-ray diffraction data were collected to 2.42 Å resolution and the crystals belonged to the monoclinic space group C121.

  7. To Reveal or To Cloak? Effects of Identity Salience on Stereotype Threat Responses in Avatar-Represented Group Contexts

    Directory of Open Access Journals (Sweden)

    Jong-Eun Roselyn Lee

    2009-01-01

    Full Text Available With rapid advances in digital technologies, the popularity of avatars — digital representations of people in computer-mediated environments — is growing. Avatars allow people to visually represent their offline social identity, or selectively render certain layer(s of their social identity less identifiable or unidentifiable in online environments. The present research investigated how African Americans, whose racial identity often suffers negative stereotyping, responded to stereotype threat when they performed a stereotype-relevant task with 2 ostensible coactors in an avatar-represented group setting. A 2 x 2 between-participants design manipulated salience of racial identity (salient vs. nonsalient and performance context (competition vs. cooperation, and assessed the extent to which participants persisted on an extremely challenging stereotype-relevant task (unsolvable anagram. The results showed that in the context of competition, participants in the race-nonsalient avatar group persisted significantly longer on the unsolvable anagram than did those in the race-salient avatar group; however, in the context of cooperation, no significant difference was found between the 2 avatar groups. The findings indicate that the effects of identity salience as varied by different types of avatars (identity-revealing vs. identity-cloaking on identity-associated threat may be moderated by the contexts of performance in which the target individuals are situated.

  8. Phenotypic, genomic, transcriptomic and proteomic changes in Bacillus cereus after a short-term space flight

    Science.gov (United States)

    Su, Longxiang; Zhou, Lisha; Liu, Jinwen; Cen, Zhong; Wu, Chunyan; Wang, Tong; Zhou, Tao; Chang, De; Guo, Yinghua; Fang, Xiangqun; Wang, Junfeng; Li, Tianzhi; Yin, Sanjun; Dai, Wenkui; Zhou, Yuping; Zhao, Jiao; Fang, Chengxiang; Yang, Ruifu; Liu, Changting

    2014-01-01

    The environment in space could affect microorganisms by changing a variety of features, including proliferation rate, cell physiology, cell metabolism, biofilm production, virulence, and drug resistance. However, the relevant mechanisms remain unclear. To explore the effect of a space environment on Bacillus cereus, a strain of B. cereus was sent to space for 398 h by ShenZhou VIII from November 1, 2011 to November 17, 2011. A ground simulation with similar temperature conditions was simultaneously performed as a control. After the flight, the flight and control strains were further analyzed using phenotypic, genomic, transcriptomic and proteomic techniques to explore the divergence of B. cereus in a space environment. The flight strains exhibited a significantly slower growth rate, a significantly higher amikacin resistance level, and changes in metabolism relative to the ground control strain. After the space flight, three polymorphic loci were found in the flight strains LCT-BC25 and LCT-BC235. A combined transcriptome and proteome analysis was performed, and this analysis revealed that the flight strains had changes in genes/proteins relevant to metabolism. In addition, certain genes/proteins that are relevant to structural function, gene expression modification and translation, and virulence were also altered. Our study represents the first documented analysis of the phenotypic, genomic, transcriptomic, and proteomic changes that occur in B. cereus during space flight, and our results could be beneficial to the field of space microbiology.

  9. Epidemiology of bacillus cereus implied in food contaminations

    International Nuclear Information System (INIS)

    Bacillus Cereus is an opportunistic pathogen. It is a causative agent in both gastrointestinal and in non gastrointestinal infections. In this study, 41 strains of Bacillus Cereus were isolated on Polymixin-Mannitol-Egg-Yolk Phenol red Agar (PMYPA) from foods (milk products, pasta, meat). These isolates were characterised and identified by biochemical and molecular tests. Pcr was performed for detection and characterisation of toxins genes in bacillus cereus. (author). 108 refs

  10. Production, Secretion and Biological Activity of Bacillus cereus Enterotoxins

    OpenAIRE

    Sonia Senesi; Emilia Ghelardi

    2010-01-01

    Bacillus cereus behaves as an opportunistic pathogen frequently causing gastrointestinal diseases, and it is increasingly recognized to be responsible for severe local or systemic infections. Pathogenicity of B. cereus mainly relies on the secretion of a wide array of toxins and enzymes and also on the ability to undergo swarming differentiation in response to surface-sensing. In this report, the pathogenicity exerted by B. cereus toxins is described with particular attention to the regulator...

  11. Induction of natural competence in Bacillus cereus ATCC14579

    OpenAIRE

    Mirończuk, Aleksandra M; Kovács, Ákos T; Kuipers, Oscar P

    2008-01-01

    Summary Natural competence is the ability of certain microbes to take up exogenous DNA from the environment and integrate it in their genome. Competence development has been described for a variety of bacteria, but has so far not been shown to occur in Bacillus cereus. However, orthologues of most proteins involved in natural DNA uptake in Bacillus subtiliscould be identified in B. cereus. Here, we report that B. cereus ATCC14579 can become naturally competent. When expressing the B. subtilis...

  12. Antimicrobial Effects of Honey on Bacillus Cereus

    OpenAIRE

    This paper should be cited as: Javadzadeh M, Najafi M, Rezaei M, Dastoor M, Behzadi AS, Amiri A . [ Antimicrobial Effects of Honey on Bacillus Cereus ]. MLJ. 201 4 ; 8 ( 2 ): 55 - 61 [Article in Persian] Javadzadeh, M. (MSc; M Najafi; Rezaei, M. (MSc; Dastoor, M. (BSc; Behzadi, AS. (MSc; Amiri, A. (MSc

    2014-01-01

    Background and Objective: Honey is a healthy and nutritious food that has been used for a long time as a treatment for different diseases. One of the applied properties of honey is its antimicrobial effect, which differs between different types of honey due to variation of phenolic and antioxidant compositions. This study aimed to assess antimicrobial effect of honey on Bacillus cereus, considering its chemical properties. Material and Methods: Three samples of honey (A1 and A2 of Khorasan Ra...

  13. Bacillus cereus cell response upon exposure to acid environment: towards the identification of potential biomarkers

    Directory of Open Access Journals (Sweden)

    Noémie eDESRIAC

    2013-10-01

    Full Text Available Microorganisms are able to adapt to different environments and evolve rapidly, allowing them to cope with their new environments. Such adaptive response and associated protections towards other lethal stresses, is a crucial survival strategy for a wide spectrum of microorganisms, including food spoilage bacteria, pathogens and organisms used in functional food applications. The growing demand for minimal processed food yields to an increasing use of combination of hurdles or mild preservation factors in the food industry. A commonly used hurdle is low pH which allows the decrease in bacterial growth rate but also the inactivation of pathogens or spoilage microorganisms. Bacillus cereus is a well-known food-borne pathogen leading to economical and safety issues in food industry. Because survival mechanisms implemented will allow bacteria to cope with environmental changes, it is important to provide understanding of B. cereus stress response. Thus this review deals with the adaptive traits of B. cereus cells facing to acid stress conditions. The acid stress response of B. cereus could be divided into four groups (i general stress response (ii pH homeostasis, (iii metabolic modifications and alkali production and (iv secondary oxidative stress response. This current knowledge may be useful to understand how B. cereus cells may cope to acid environment such as encountered in food products and thus to find some molecular biomarkers of the bacterial behaviour. These biomarkers could be furthermore used to develop new microbial behaviour prediction tools which can provide insights into underlying molecular physiological states which govern the behaviour of microorganisms and thus opening the avenue toward the detection of stress adaptive behaviour at an early stage and the control of stress-induced resistance throughout the food chain.

  14. Bacillus cereus cell response upon exposure to acid environment: toward the identification of potential biomarkers.

    Science.gov (United States)

    Desriac, Noémie; Broussolle, Véronique; Postollec, Florence; Mathot, Anne-Gabrielle; Sohier, Danièle; Coroller, Louis; Leguerinel, Ivan

    2013-01-01

    Microorganisms are able to adapt to different environments and evolve rapidly, allowing them to cope with their new environments. Such adaptive response and associated protections toward other lethal stresses, is a crucial survival strategy for a wide spectrum of microorganisms, including food spoilage bacteria, pathogens, and organisms used in functional food applications. The growing demand for minimal processed food yields to an increasing use of combination of hurdles or mild preservation factors in the food industry. A commonly used hurdle is low pH which allows the decrease in bacterial growth rate but also the inactivation of pathogens or spoilage microorganisms. Bacillus cereus is a well-known food-borne pathogen leading to economical and safety issues in food industry. Because survival mechanisms implemented will allow bacteria to cope with environmental changes, it is important to provide understanding of B. cereus stress response. Thus this review deals with the adaptive traits of B. cereus cells facing to acid stress conditions. The acid stress response of B. cereus could be divided into four groups (i) general stress response (ii) pH homeostasis, (iii) metabolic modifications and alkali production and (iv) secondary oxidative stress response. This current knowledge may be useful to understand how B. cereus cells may cope to acid environment such as encountered in food products and thus to find some molecular biomarkers of the bacterial behavior. These biomarkers could be furthermore used to develop new microbial behavior prediction tools which can provide insights into underlying molecular physiological states which govern the behavior of microorganisms and thus opening the avenue toward the detection of stress adaptive behavior at an early stage and the control of stress-induced resistance throughout the food chain. PMID:24106490

  15. A procedure for estimating Bacillus cereus spores in soil and stream-sediment samples - A potential exploration technique

    Science.gov (United States)

    Watterson, J.R.

    1985-01-01

    The presence of bacterial spores of the Bacillus cereus group in soils and stream sediments appears to be a sensitive indicator of several types of concealed mineral deposits, including vein-type gold deposits. The B. cereus assay is rapid, inexpensive, and inherently reproducible. The test, currently under investigation for its potential in mineral exploration, is recommended for use on a research basis. Among the aerobic spore-forming bacilli, only B. cereus and closely related strains produce an opaque zone in egg-yolk emulsion agar. This characteristic, also known as the Nagler of lecitho-vitellin reaction, has long been used to rapidly indentify and estimate presumptive B. cereus. The test is here adapted to permit rapid estimation of B. cereus spores in soil and stream-sediment samples. Relative standard deviation was 10.3% on counts obtained from two 40-replicate pour-plate determinations. As many as 40 samples per day can be processed. Enough procedural detail is included to permit investigation of the test in conventional geochemical laboratories using standard microbiological safety precautions. ?? 1985.

  16. Response of bacillus cereus to heat and or Bacillus cereus Irradiation Treatments

    International Nuclear Information System (INIS)

    Exposure of bacillus cereus spores to gamma radiation gave D10 value of 1.59 kGy. The combined effect of heating prior or post irradiation revealed that the latter treatment was more effective than the former in reducing the viable count of the pathogenic bacterial spores. Irradiation of B. cereus spores. in Koshari (initial count of 4 X 105 CFU-ml) followed by heating totally arrested growth of the bacterium. It reduced the total count from 2 X 107 to 0.83 X 10 CFU/ml. Coupling 10% garlic with irradiation and heating completely stopped spore germination and reduced the total bacterial count from 2 107 to 0.16 X 10 CFU/ml. combining pH with irradiation and heating completely hampered the viable count for B. cereus and total bacterial count. The combined effect of garlic extract (10% v/v) and ph 4 on b. cereus in koshari, was a reduction in the viable count from 3.6 X 105 to 1.9 X 105 CFU/ml and the total bacterial count from 1 X 107 to 3.5 X 105 CFU/ml. 1 fig., 4 tab

  17. Bacillus cereus: emetic toxin production and gamma hypothesis for growth

    NARCIS (Netherlands)

    Biesta-Peters, E.G.

    2011-01-01

    Bacillus cereus is a food spoilage microorganism and a pathogen. Growth of B. cereus can be prevented or delayed by adding growth limiting compounds to the food product or by altered storage conditions. Combinations of growth limiting factors

  18. Draft Genome Sequence of Biocontrol Agent Bacillus cereus UW85.

    Science.gov (United States)

    Lozano, Gabriel L; Holt, Jonathan; Ravel, Jacques; Rasko, David A; Thomas, Michael G; Handelsman, Jo

    2016-01-01

    Bacillus cereus UW85 was isolated from a root of a field-grown alfalfa plant from Arlington, WI, and identified for its ability to suppress damping off, a disease caused by Phytophthora megasperma f. sp. medicaginis on alfalfa. Here, we report the draft genome sequence of B. cereus UW85, obtained by a combination of Sanger and Illumina sequencing. PMID:27587823

  19. Semiautomated Metabolic Staining Assay for Bacillus cereus Emetic Toxin

    OpenAIRE

    Finlay, W. J. J.; Logan, N A; Sutherland, A. D.

    1999-01-01

    This paper describes a specific, sensitive, semiautomated, and quantitative Hep-2 cell culture-based 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay for Bacillus cereus emetic toxin. Of nine Bacillus, Brevibacillus, and Paenibacillus species assessed for emetic toxin production, only B. cereus was cytotoxic.

  20. Autoinducer 2 Affects Biofilm Formation by Bacillus cereus

    OpenAIRE

    Auger, Sandrine; Krin, Evelyne; Aymerich, Stéphane; Gohar, Michel

    2006-01-01

    Cell-free supernatants from growing Bacillus cereus strain ATCC 10987 induced luminescence in a Photorhabdus luminescens ΔluxS mutant, indicating the production of functional autoinducer 2 (AI-2). The exogenous addition of in vitro synthesized AI-2 had an inhibitory effect on biofilm formation by B. cereus and promoted release of the cells from a preformed biofilm.

  1. Capsule Production in Bacillus cereus Strains Associated with Severe Pneumonia

    OpenAIRE

    Sue, David; Hoffmaster, Alex R.; Popovic, Tanja; Wilkins, Patricia P.

    2006-01-01

    We identified three encapsulated Bacillus cereus strains, isolated from patients with severe pneumonia, in a collection of B. cereus isolates associated with human illness. We found that the extent of capsule expression was influenced by culturing conditions. Our findings highlight consequent clinical and laboratory diagnostic challenges posed by such isolates.

  2. Crystallization and preliminary crystallographic analysis of the NheA component of the Nhe toxin from Bacillus cereus

    International Nuclear Information System (INIS)

    The NheA component of the B. cereus Nhe toxin was overexpressed in E. coli, purified and crystallized. Diffraction data were collected and processed to 2.05 Å resolution. The nonhaemolytic enterotoxin (Nhe) of Bacillus cereus plays a key role in cases of B. cereus food poisoning. The toxin is comprised of three different proteins: NheA, NheB and NheC. Here, the expression in Escherichia coli, purification and crystallization of the NheA protein are reported. The protein was crystallized by the sitting-drop vapour-diffusion method using PEG 3350 as a precipitant. The crystals of NheA diffracted to 2.05 Å resolution and belonged to space group C2, with unit-cell parameters a = 308.7, b = 58.2, c = 172.9 Å, β = 110.6°. Calculation of VM values suggests that there are approximately eight protein molecules per asymmetric unit

  3. Diversity of sugar acceptor of glycosyltransferase 1 from Bacillus cereus and its application for glucoside synthesis.

    Science.gov (United States)

    Chiu, Hsi-Ho; Shen, Mo-Yuan; Liu, Yuan-Ting; Fu, Yu-Lieh; Chiu, Yu-An; Chen, Ya-Huei; Huang, Chin-Ping; Li, Yaw-Kuen

    2016-05-01

    Glycosyltransferase 1 from Bacillus cereus (BcGT1) catalyzes the transfer of a glucosyl moiety from uridine diphosphate glucose (UDP-glucose) to various acceptors; it was expressed and characterized. The specificity of acceptors was found to be broad: more than 20 compounds classified into O-, S-, and N-linkage glucosides can be prepared with BcGT1 catalysis. Based on this work, we conclude that the corresponding acceptors of these compounds must possess the following features: (1) the acceptors must contain at least one aromatic or fused-aromatic or heteroaromatic ring; (2) the reactive hydroxyl or sulfhydryl or amino group can attach either on the aromatic ring or on its aliphatic side chain; and (3) the acceptors can be a primary, secondary, or even a tertiary amine. Four representative acceptors-fluorescein methyl ester, 17-β-estradiol, 7-mercapto-4-methylcoumarin, and 6-benzylaminopurine-were chosen as a candidate acceptor for O-, S-, and N-glucosidation, respectively. These enzymatic products were purified and the structures were confirmed with mass and NMR spectra. As all isolated glucosides are β-anomers, BcGT1 is confirmed to be an inverting enzyme. This study not only demonstrates the substrate promiscuity of BcGT1 but also showed the great application prospect of this enzyme in bioconversion of valuable bioactive molecules. PMID:26795959

  4. High-level production of Bacillus cereus phospholipase C in Corynebacterium glutamicum.

    Science.gov (United States)

    Ravasi, Pablo; Braia, Mauricio; Eberhardt, Florencia; Elena, Claudia; Cerminati, Sebastián; Peirú, Salvador; Castelli, Maria Eugenia; Menzella, Hugo G

    2015-12-20

    Enzymatic oil degumming (removal of phospholipids) using phospholipase C (PLC) is a well-established and environmentally friendly process for vegetable oil refining. In this work, we report the production of recombinant Bacillus cereus PLC in Corynebacterium glutamicum ATCC 13869 in a high cell density fermentation process and its performance in soybean oil degumming. A final concentration of 5.5g/L of the recombinant enzyme was achieved when the respective gene was expressed from the tac promoter in a semi-defined medium. After treatment with trypsin to cleave the propeptide, the mature enzyme completely hydrolyzed phosphatidylcholine and phosphatidylethanolamine, which represent 70% of the phospholipids present in soybean oil. The results presented here show the feasibility of using B. cereus PLC for oil degumming and provide a manufacturing process for the cost effective production of this enzyme. PMID:26519562

  5. Butanol production under microaerobic conditions with a symbiotic system of Clostridium acetobutylicum and Bacillus cereus

    OpenAIRE

    Wu, Pengfei; Wang, Genyu; Wang, Gehua; Børresen, Børre Tore; Liu, Hongjuan; Zhang, Jianan

    2016-01-01

    Background One major problem of ABE (acetone, butanol and ethanol) fermentation is high oxygen sensitivity of Clostridium acetobutylicum. Currently, no single strain has been isolated or genetically engineered to produce butanol effectively under aerobic conditions. In our previous work, a symbiotic system TSH06 has been developed successfully by our group, and two strains, C. acetobutylicum TSH1 and Bacillus cereus TSH2, were isolated from TSH06. Results Compared with single culture, TSH06 s...

  6. Genome analysis of Elusimicrobium minutum, the first cultivated representative of the Elusimicrobia phylum (formerly Termite Group 1)

    Energy Technology Data Exchange (ETDEWEB)

    Herlemann, D. P. R.; Geissinger, O.; Ikeda-Ohtsubo, W.; Kunin, V.; Sun, H.; Lapidus, A.; Hugenholtz, P.; Brune, A.

    2009-02-01

    The candidate phylum Termite group 1 (TG1), is regularly 1 encountered in termite hindguts but is present also in many other habitats. Here we report the complete genome sequence (1.64 Mbp) of Elusimicrobium minutum strain Pei191{sup T}, the first cultured representative of the TG1 phylum. We reconstructed the metabolism of this strictly anaerobic bacterium isolated from a beetle larva gut and discuss the findings in light of physiological data. E. minutum has all genes required for uptake and fermentation of sugars via the Embden-Meyerhof pathway, including several hydrogenases, and an unusual peptide degradation pathway comprising transamination reactions and leading to the formation of alanine, which is excreted in substantial amounts. The presence of genes encoding lipopolysaccharide biosynthesis and the presence of a pathway for peptidoglycan formation are consistent with ultrastructural evidence of a Gram-negative cell envelope. Even though electron micrographs showed no cell appendages, the genome encodes many genes putatively involved in pilus assembly. We assigned some to a type II secretion system, but the function of 60 pilE-like genes remains unknown. Numerous genes with hypothetical functions, e.g., polyketide synthesis, non-ribosomal peptide synthesis, antibiotic transport, and oxygen stress protection, indicate the presence of hitherto undiscovered physiological traits. Comparative analysis of 22 concatenated single-copy marker genes corroborated the status of Elusimicrobia (formerly TG1) as a separate phylum in the bacterial domain, which was so far based only on 16S rRNA sequence analysis.

  7. Positional group significantly influences the offensive and defensive skill involvements of junior representative rugby league players during match play.

    Science.gov (United States)

    Bennett, Kyle J M; Fransen, Job; Scott, Brendan R; Sanctuary, Colin E; Gabbett, Tim J; Dascombe, Ben J

    2016-08-01

    This study examined the skill involvements of three positional groups across a junior representative rugby league season. Data were collected from 45 rugby league players (mean ± SD; age = 16.5 ± 1.0 years) currently participating in the Harold Matthews and SG Ball Cup. Players were subdivided into hit-up forwards, adjustables and outside backs. The frequency (n · min(-1)) of offensive, defensive and overall involvements was coded for each group using a notation system and a practical coach skill analysis tool. Multivariate analysis of variance (MANOVA) revealed a significant effect of playing position on skill involvements (F = 9.06; P < 0.001; ES = 0.41). Hit-up forwards performed a significantly greater frequency of offensive (0.31 ± 0.10), defensive (0.42 ± 0.15) and overall involvements (0.74 ± 0.19) when compared to adjustables (0.20 ± 0.08, 0.28 ± 0.08 and 0.52 ± 0.15, respectively) and outside backs (0.20 ± 0.12, 0.11 ± 0.07 and ± 0.31 ± 0.17, respectively). Further, adjustables performed a significantly greater number of defensive (0.28 ± 0.08) and overall involvements (0.52 ± 0.15) when compared to outside backs (0.11 ± 0.07 and 0.31 ± 0.17, respectively). The findings of this study suggest that it is important to consider a junior player's positional group when analysing their skill involvements. Information gained from this study could assist in the design of specific training methodologies for junior rugby league players in high-level talent development programmes. PMID:26651383

  8. Comparative analysis of two-component signal transduction systems of Bacillus cereus, Bacillus thuringiensis and Bacillus anthracis

    NARCIS (Netherlands)

    Been, M.W.H.J. de; Francke, C.; Moezelaar, R.; Abee, T.; Siezen, R.J.

    2006-01-01

    Members of the Bacillus cereus group are ubiquitously present in the environment and can adapt to a wide range of environmental fluctuations. In bacteria, these adaptive responses are generally mediated by two-component signal transduction systems (TCSs), which consist of a histidine kinase (HK) and

  9. Antimicrobial Effects of Honey on Bacillus Cereus

    Directory of Open Access Journals (Sweden)

    This paper should be cited as: Javadzadeh M, Najafi M, Rezaei M, Dastoor M, Behzadi AS, Amiri A . [ Antimicrobial Effects of Honey on Bacillus Cereus ]. MLJ. 201 4 ; 8 ( 2 : 55 - 61 [Article in Persian] Javadzadeh, M. (MSc

    2014-05-01

    Full Text Available Background and Objective: Honey is a healthy and nutritious food that has been used for a long time as a treatment for different diseases. One of the applied properties of honey is its antimicrobial effect, which differs between different types of honey due to variation of phenolic and antioxidant compositions. This study aimed to assess antimicrobial effect of honey on Bacillus cereus, considering its chemical properties. Material and Methods: Three samples of honey (A1 and A2 of Khorasan Razavi Province and A3 of South Khorasan province (were prepared and studied in terms of chemical parameters .The antibacterial effect of honey was surveyed throughTurbidimeter using spectrometer with incubator time of 2, 4, 6, and 8hrs. the level of turbidity caused by bacterium growth was measured at different times with a wavelength of 600nm. Results: According to the study, the samples containing higher concentration of polyphenol has more antimicrobial activity. The samples of A2, A3, and A1 had the highest concentration of polyphenol, respectively. Conclusion: The results indicate the prebiotic effect of honey that can be justified by the presence of fructo-oligosacharids and vitamin B. Keywords: Honey, Bacillus Cereus, Antibacterial, Turbidimetry.

  10. Purification, crystallization and preliminary characterization of a putative LmbE-like deacetylase from Bacillus cereus

    International Nuclear Information System (INIS)

    The BC1534 protein from B. cereus was purified and crystallized and a native X-ray diffraction data set was collected to 2.5 Å using synchrotron radiation. The Bacillus cereus BC1534 protein, a putative deacetylase from the LmbE family, has been purified to homogeneity and crystallized using the hanging-drop vapour-diffusion method. Crystals of the 26 kDa protein grown from MPD and acetate buffer belong to space group R32, with unit-cell parameters a = b = 76.7, c = 410.5 Å (in the hexagonal setting). A complete native data set was collected to a resolution of 2.5 Å from a single cryoprotected crystal using synchrotron radiation. As BC1534 shows significant sequence homology with an LmbE-like protein of known structure from Thermus thermophilus, molecular replacement will be used for crystal structure determination

  11. Purification, crystallization and preliminary X-ray crystallographic analysis of chitinase from Bacillus cereus NCTU2

    International Nuclear Information System (INIS)

    The crystallization of B. cereus chitinase is reported. Chitinases (EC 3.2.1.14) are found in a broad range of organisms, including bacteria, fungi and higher plants, and play different roles depending on their origin. A chitinase from Bacillus cereus NCTU2 (ChiNCTU2) capable of hydrolyzing chitin as a carbon and nitrogen nutrient has been identified as a member of the family 18 glycoside hydrolases. ChiNCTU2 of molecular weight 36 kDa has been crystallized using the hanging-drop vapour-diffusion method. According to the diffraction of chitinase crystals at 1.10 Å resolution, the crystal belongs to space group P21, with unit-cell parameters a = 50.79, b = 48.79, c = 66.87 Å, β = 99.31°. Preliminary analysis indicates there is one chitinase molecule in the asymmetric unit, with a solvent content of 43.4%

  12. Expression, crystallization and preliminary X-ray crystallographic analysis of aldehyde dehydrogenase (ALDH) from Bacillus cereus

    International Nuclear Information System (INIS)

    Aldehyde dehydrogenase (ALDH) catalyses the oxidation of aldehydes using NAD(P)+ as a cofactor. The aldh gene from B. cereus was cloned; the protein was expressed, purified and crystallized, and a preliminary X-ray crystallography analysis was performed. Aldehyde dehydrogenase (ALDH) catalyses the oxidation of aldehydes using NAD(P)+ as a cofactor. Most aldehydes are toxic at low levels. ALDHs are used to regulate metabolic intermediate aldehydes. The aldh gene from Bacillus cereus was cloned and the ALDH protein was expressed, purified and crystallized. A crystal of the ALDH protein diffracted to 2.6 Å resolution and belonged to the monoclinic space group P21, with unit-cell parameters a = 83.5, b = 93.3, c = 145.5 Å, β = 98.05°. Four protomers were present in the asymmetric unit, with a corresponding VM of 2.55 Å3 Da−1 and a solvent content of 51.8%

  13. Bacterial succession and metabolite changes during flax (Linum usitatissimum L.) retting with Bacillus cereus HDYM-02.

    Science.gov (United States)

    Zhao, Dan; Liu, Pengfei; Pan, Chao; Du, Renpeng; Ping, Wenxiang; Ge, Jingping

    2016-01-01

    High-throughput sequencing and GC-MS (gas chromatography-mass spectrometry) were jointly used to reveal the bacterial succession and metabolite changes during flax (Linum usitatissimum L.) retting. The inoculation of Bacillus cereus HDYM-02 decreased bacterial richness and diversity. This inoculum led to the replacement of Enterobacteriaceae by Bacillaceae. The level of aerobic Pseudomonadaceae (mainly Azotobacter) and anaerobic Clostridiaceae_1 gradually increased and decreased, respectively. Following the addition of B. cereus HDYM-02, the dominant groups were all degumming enzyme producers or have been proven to be involved in microbial retting throughout the entire retting period. These results could be verified by the metabolite changes, either degumming enzymes or their catalytic products galacturonic acid and reducing sugars. The GC-MS data showed a clear separation between flax retting with and without B. cereus HDYM-02, particularly within the first 72 h. These findings reveal the important bacterial groups that are involved in fiber retting and will facilitate improvements in the retting process. PMID:27585559

  14. Dynamic Analysis of the Evolution of Cereus peruvianus (Cactaceae Areas Attacked by Phoma sp.

    Directory of Open Access Journals (Sweden)

    Gyorgy FESZT

    2009-12-01

    Full Text Available Cereus Peruvianus (night blooming Cereus, or peruvian apple is one of the sensitive species to Phoma attack. Photographic images can intercept a certain phytopathology, at a certain moment. The computerized analysis of such an image turns into a value the spread which the phytopathological process has at that moment. The purpose of this study is to assimilate the technique of achieving successions of digital photos of Cereus peruvianus f. monstruosa attacked by Phoma sp. Parallely with recording the images, with the help of Rhythm digital temperature humidity controller, were recorded data about the green house microclimate (air humidity-minimum and maximum, temperature-minimum and maximum. In the first stage of the study, the attack presents small fluctuations, reaching a high level in days with low temperatures. So, the most significant growths were recorded in the periods: 10. 02. 2005-20. 02. 2005 with an affected area of 10.97-8.82 = 2.15 and 11. 03. 2005-22. 04. 2005 with growth differences of 14.67-13.32 = 1.35. Generally, the affected areas grow in days with low minimum temperatures. The great advantage of this technique is represented by the possibility of using in situ in home areas of species or crop plants in fields. Repeated images, achieved in time, then overlapped, can provide important data on the evolution of affected areas.

  15. Global transcriptome analysis of Bacillus cereus ATCC 14579 in response to silver nitrate stress

    Directory of Open Access Journals (Sweden)

    Ganesh Babu Malli Mohan

    2011-11-01

    Full Text Available Abstract Silver nanoparticles (AgNPs were synthesized using Bacillus cereus strains. Earlier, we had synthesized monodispersive crystalline silver nanoparticles using B. cereus PGN1 and ATCC14579 strains. These strains have showed high level of resistance to silver nitrate (1 mM but their global transcriptomic response has not been studied earlier. In this study, we investigated the cellular and metabolic response of B. cereus ATCC14579 treated with 1 mM silver nitrate for 30 & 60 min. Global expression profiling using genomic DNA microarray indicated that 10% (n = 524 of the total genes (n = 5234 represented on the microarray were up-regulated in the cells treated with silver nitrate. The majority of genes encoding for chaperones (GroEL, nutrient transporters, DNA replication, membrane proteins, etc. were up-regulated. A substantial number of the genes encoding chemotaxis and flagellar proteins were observed to be down-regulated. Motility assay of the silver nitrate treated cells revealed reduction in their chemotactic activity compared to the control cells. In addition, 14 distinct transcripts overexpressed from the 'empty' intergenic regions were also identified and proposed as stress-responsive non-coding small RNAs.

  16. Time dynamics of the Bacillus cereus exoproteome are shaped by cellular oxidation

    Directory of Open Access Journals (Sweden)

    Jean-Paul eMadeira

    2015-04-01

    Full Text Available At low density, Bacillus cereus cells release a large variety of proteins into the extracellular medium when cultivated in pH-regulated, glucose-containing minimal medium, either in the presence or absence of oxygen. The majority of these exoproteins are putative virulence factors, including toxin-related proteins. Here, B. cereus exoproteome time courses were monitored by nanoLC-MS/MS under low-oxidoreduction potential (ORP anaerobiosis, high-ORP anaerobiosis, and aerobiosis, with a specific focus on oxidative-induced post-translational modifications of methionine residues. Principal component analysis (PCA of the exoproteome dynamics indicated that toxin-related proteins were the most representative of the exoproteome changes, both in terms of protein abundance and their methionine sulfoxide (Met(O content. PCA also revealed an interesting interconnection between toxin-, metabolism-, and oxidative stress–related proteins, suggesting that the abundance level of toxin-related proteins, and their Met(O content in the B. cereus exoproteome, reflected the cellular oxidation under both aerobiosis and anaerobiosis.

  17. Production, Secretion and Biological Activity of Bacillus cereus Enterotoxins

    Directory of Open Access Journals (Sweden)

    Sonia Senesi

    2010-06-01

    Full Text Available Bacillus cereus behaves as an opportunistic pathogen frequently causing gastrointestinal diseases, and it is increasingly recognized to be responsible for severe local or systemic infections. Pathogenicity of B. cereus mainly relies on the secretion of a wide array of toxins and enzymes and also on the ability to undergo swarming differentiation in response to surface-sensing. In this report, the pathogenicity exerted by B. cereus toxins is described with particular attention to the regulatory mechanisms of production and secretion of HBL, Nhe and CytK enterotoxins.

  18. Comparative transcriptional profiling of Bacillus cereus sensu lato strains during growth in CO2-bicarbonate and aerobic atmospheres.

    Directory of Open Access Journals (Sweden)

    Karla D Passalacqua

    Full Text Available BACKGROUND: Bacillus species are spore-forming bacteria that are ubiquitous in the environment and display a range of virulent and avirulent phenotypes. This range is particularly evident in the Bacillus cereus sensu lato group; where closely related strains cause anthrax, food-borne illnesses, and pneumonia, but can also be non-pathogenic. Although much of this phenotypic range can be attributed to the presence or absence of a few key virulence factors, there are other virulence-associated loci that are conserved throughout the B. cereus group, and we hypothesized that these genes may be regulated differently in pathogenic and non-pathogenic strains. METHODOLOGY/PRINCIPAL FINDINGS: Here we report transcriptional profiles of three closely related but phenotypically unique members of the Bacillus cereus group--a pneumonia-causing B. cereus strain (G9241, an attenuated strain of B. anthracis (Sterne 34F(2, and an avirulent B. cereus strain (10987--during exponential growth in two distinct atmospheric environments: 14% CO(2/bicarbonate and ambient air. We show that the disease-causing Bacillus strains undergo more distinctive transcriptional changes between the two environments, and that the expression of plasmid-encoded virulence genes was increased exclusively in the CO(2 environment. We observed a core of conserved metabolic genes that were differentially expressed in all three strains in both conditions. Additionally, the expression profiles of putative virulence genes in G9241 suggest that this strain, unlike Bacillus anthracis, may regulate gene expression with both PlcR and AtxA transcriptional regulators, each acting in a different environment. CONCLUSIONS/SIGNIFICANCE: We have shown that homologous and even identical genes within the genomes of three closely related members of the B. cereus sensu lato group are in some instances regulated very differently, and that these differences can have important implications for virulence. This study

  19. Bacillus cereus immune escape: a journey within macrophages.

    Science.gov (United States)

    Tran, Seav-Ly; Ramarao, Nalini

    2013-10-01

    During bacterial infection, professional phagocytes are attracted to the site of infection, where they constitute a first line of host cell defense. Their function is to engulf and destroy the pathogens. Thus, bacteria must withstand the bactericidal activity of professional phagocytes, including macrophages to counteract the host immune system. Bacillus cereus infections are characterized by bacteremia despite the accumulation of inflammatory cells at the site of infection. This implies that the bacteria have developed means of resisting the host immune system. Bacillus cereus spores survive, germinate, and multiply in contact with macrophages, eventually producing toxins that kill these cells. However, the exact mechanism by which B. cereus evades immune attack remains unclear. This review addresses the interaction between B. cereus and macrophages, highlighting, in particular, the ways in which the bacteria escape the microbicidal activities of professional phagocytes. PMID:23827020

  20. Complete genome sequence of the cold-active bacteriophage VMY22 from Bacillus cereus.

    Science.gov (United States)

    Qin, Kunhao; Cheng, Benxu; Zhang, Shengting; Wang, Nan; Fang, Yuan; Zhang, Qi; Kuang, Anxiu; Lin, Lianbing; Ji, Xiuling; Wei, Yunlin

    2016-06-01

    The cold-active bacteriophage VMY22, belonging to the Podoviridae family, was isolated from Mingyong Glacier in China. Sequence analysis revealed that the genome is 18,609 bp long, with an overall G + C content of 36.4 mol%, and 25 open reading frames (ORFs). The sequence contains 46 potential promoters, 6 transcription terminators, and no tRNAs. Most of the ORFs show a high degree of similarity to B103 (NC_004165). Two noteworthy findings were made. First, one of the predicted proteins, ORF 19, shows high sequence similarity to the bacteriocin biosynthesis protein from Bacillus cereus. From this information, we propose that the VMY22 phage is at an intermediate phase in its coevolution with its bacterial host. Second, seven of the hypothetical proteins appear to be unique to this cold-active B. cereus phage (i.e., not found in temperate-active B. cereus phages). These observations add to our current knowledge about the coevolution of bacteriophages and their hosts. The identification of a novel group of gene and protein structures and functions will lead to a better understanding of cold-adaptation mechanisms in bacteria and their bacteriophages. PMID:26941234

  1. Comparison of hand hygiene procedures for removing Bacillus cereus spores.

    Science.gov (United States)

    Sasahara, Teppei; Hayashi, Shunji; Hosoda, Kouichi; Morisawa, Yuji; Hirai, Yoshikazu

    2014-01-01

    Bacillus cereus is a spore-forming bacterium. B. cereus occasionally causes nosocomial infections, in which hand contamination with the spores plays an important role. Therefore, hand hygiene is the most important practice for controlling nosocomial B. cereus infections. This study aimed to determine the appropriate hand hygiene procedure for removing B. cereus spores. Thirty volunteers' hands were experimentally contaminated with B. cereus spores, after which they performed 6 different hand hygiene procedures. We compared the efficacy of the procedures in removing the spores from hands. The alcohol-based hand-rubbing procedures scarcely removed them. The soap washing procedures reduced the number of spores by more than 2 log10. Extending the washing time increased the spore-removing efficacy of the washing procedures. There was no significant difference in efficacy between the use of plain soap and antiseptic soap. Handwashing with soap is appropriate for removing B. cereus spores from hands. Alcohol-based hand-rubbing is not effective. PMID:25252644

  2. Characterization of toxin complex gene clusters and insect toxicity of bacteria representing four sub-groups of Pseudomonas fluorescens

    Science.gov (United States)

    Ten strains representing four lineages of Pseudomonas (P. chlororaphis, P. corrugata, P. koreensis, and P. fluorescens subgroups) were evaluated for toxicity to the tobacco hornworm Manduca sexta and the fruit fly Drosophila melanogaster. The three strains within the P. chlororaphis subgroup exhibi...

  3. To Reveal or To Cloak? Effects of Identity Salience on Stereotype Threat Responses in Avatar-Represented Group Contexts

    OpenAIRE

    Jong-Eun Roselyn Lee

    2009-01-01

    With rapid advances in digital technologies, the popularity of avatars — digital representations of people in computer-mediated environments — is growing. Avatars allow people to visually represent their offline social identity, or selectively render certain layer(s) of their social identity less identifiable or unidentifiable in online environments. The present research investigated how African Americans, whose racial identity often suffers negative stereotyping, responded to stereotype thre...

  4. Chemical and immunological comparison of surface fibrils of strains representing six taxonomic groups of Actinomyces viscosus and Actinomyces naeslundii.

    OpenAIRE

    Masuda, N.; Ellen, R P; Fillery, E D; Grove, D A

    1983-01-01

    Human isolates of Actinomyces viscosus and Actinomyces naeslundii have been divided into six clusters in a numerical taxonomy study. Surface fibrils of strains representing these clusters were isolated and purified. Chemical analyses revealed that the major component of all fibrils was protein and that although differences in percentages of specific amino acid residues were found, the relative proportions of basic, acidic, polar uncharged, and nonpolar amino acids were rather similar among cl...

  5. The Retention and Success of Under-Represented Groups in a Bachelor of Education Program in New Zealand

    Science.gov (United States)

    Millward, Pamela; Turner, Rolf; Van Der Linden, Deirdre

    2012-01-01

    For several decades researchers have raised questions regarding factors that enable undergraduate students, particularly those from ethnic minority groups living in low socio-economic areas, to persist with their studies to degree completion. Seeking answers to these questions becomes more urgent as universities around the world enrol increasingly…

  6. Communication of 1 October 2009 received from the Resident Representative of Hungary to the Agency on behalf of the Participating Governments of the Nuclear Suppliers Group

    International Nuclear Information System (INIS)

    The Director General has received a letter dated 1 October 2009 from the Resident Representative of Hungary to the Agency on behalf of the Participating Governments of the Nuclear Suppliers Group. Attached to this letter is an updated version of a paper entitled 'The Nuclear Suppliers Group: Its Origins, Role and Activities.' The original version of this paper was issued as INFCIRC/539 on 15 September 1997: revisions were issued on 17 April 2000, 16 September 2003 and 30 May 2005

  7. Invasive Bacillus cereus Infection in a Renal Transplant Patient: A Case Report and Review

    OpenAIRE

    Susan John; John Neary; Lee, Christine H

    2012-01-01

    Bacillus cereus is a common cause of gastrointestinal diseases. The majority of individuals with B cereus-related food poisoning recover without any specific treatment. It can, however, rarely cause invasive disease in immunocompromised patients.

  8. Invasive Bacillus cereus infection in a renal transplant patient: A case report and review.

    Science.gov (United States)

    John, Susan; Neary, John; Lee, Christine H

    2012-01-01

    Bacillus cereus is a common cause of gastrointestinal diseases. The majority of individuals with B cereus-related food poisoning recover without any specific treatment. It can, however, rarely cause invasive disease in immunocompromised patients. PMID:24294281

  9. The water cycle, a potential source of the bacterial pathogen Bacillus cereus

    OpenAIRE

    Julien Brillard; Dupont, Christian M. S.; Odile Berge; Claire Dargaignaratz; Stéphanie Oriol-Gagnier; Claude Doussan; Véronique Broussolle; Marina Gillon; Thierry Clavel; Annette Bérard

    2015-01-01

    The behaviour of the sporulating soil-dwelling Bacillus cereus sensu lato (B. cereus sl) which includes foodborne pathogenic strains has been extensively studied in relation to its various animal hosts. The aim of this environmental study was to investigate the water compartments (rain and soil water, as well as groundwater) closely linked to the primary B. cereus sl reservoir, for which available data are limited. B. cereus sl was present, primarily as spores, in all of the tested compartmen...

  10. Teacher Autonomy in the United States: Establishing a Standard Definition, Validation of a Nationally Representative Construct and an Investigation of Policy Affected Teacher Groups

    Science.gov (United States)

    Gwaltney, Kevin Dale

    2012-01-01

    This effort: 1) establishes an autonomy definition uniquely tailored for teaching, 2) validates a nationally generalizable teacher autonomy construct, 3) demonstrates that the model describes and explains the autonomy levels of particular teacher groups, and 4) verifies the construct can represent teacher autonomy in other empirical models. The…

  11. Draft Genome Sequence of Bacillus cereus LCT-BC25, Isolated from Space Flight

    OpenAIRE

    Zhang, Xuelin; Wang, Tong; Su, Longxiang; Zhou, Lisha; Li, Tianzhi; Wang, Junfeng; Liu, Yan; Jiang, Xuege; Wu, Chunyan; Liu, Changting

    2014-01-01

    Bacillus cereus strain LCT-BC25, which was carried by the Shenzhou VIII spacecraft, traveled in space for about 398 h. To investigate the response of B. cereus to space environments, we determined the genome sequence of B. cereus strain LCT-BC25, which was isolated after space flight.

  12. Genome Sequence of Bacillus cereus Phage vB_BceS-MY192

    OpenAIRE

    Yang, Yong; Zhan, Li; Chen, Jiancai; Zhang, Yunyi; Sun, Yi; Yang, Zhangnv; Jiang, Liping; Zhu, Hanping; Zhang, Yanjun; Lu, Yiyu; Mei, Lingling

    2016-01-01

    Bacillus cereus is an opportunistic foodborne pathogen. The phage vB_BceS-MY192 was isolated from B. cereus 192 in a cooked rice sample. The temperate phage belongs to the Siphoviridae family, Caudovirales order. Here we announce the phage genome sequence and its annotation, which may expand the understanding of B. cereus siphophages.

  13. Cd-Resistant Strains of B. cereus S5 with Endurance Capacity and Their Capacities for Cadmium Removal from Cadmium-Polluted Water

    Science.gov (United States)

    Wu, Huiqing; Wu, Qingping; Wu, Guojie; Gu, Qihui; Wei, Linting

    2016-01-01

    The goal of this study was to identify Cd-resistant bacterial strains with endurance capacity and to evaluate their ability to remove cadmium ions from cadmium-polluted water. The Bacillus cereusS5 strain identified in this study had the closest genetic relationship with B. cereus sp. Cp1 and performed well in the removal of Cd2+ions from solution. The results showed that both the live and dead biomasses of the Cd2+-tolerant B. cereus S5 strain could absorb Cd2+ ions in solution but that the live biomass of the B. cereus S5 strain outperformed the dead biomass at lower Cd2+concentrations. An analysis of the cadmium tolerance genes of B. cereus S5 identified ATPase genes that were associated with cadmium tolerance and involved in the ATP pumping mechanism. The FTIR spectra revealed the presence of amino, carboxyl and hydroxyl groups on the pristine biomass and indicated that the cadmium ion removal ability was related to the structure of the strain. The maximum absorption capacity of the B. cereus S5 strain in viable spore biomass was 70.16 mg/g (dry weight) based on a pseudo-second-order kinetic model fit to the experimental data. The Langmuir and Langmuir-Freundlich isotherm adsorption models fit the cadmium ion adsorption data well, and the kinetic curves indicated that the adsorption rate was second-order. For Cd2+ concentrations (mg/L) of 1–109 mg/L, good removal efficiency (>80%) was achieved using approximately 3.48–10.3 g/L of active spore biomass of the B. cereus S5 strain. A cadmium-tolerant bacteria-activated carbon-immobilized column could be used for a longer duration and exhibited greater treatment efficacy than the control column in the treatment of cadmium-polluted water. In addition, a toxicity assessment using mice demonstrated that the biomass of the B. cereus S5 strain and its fermentation products were non-toxic. Thus, the isolated B. cereus S5 strain can be considered an alternative biological adsorbent for use in emergency responses to

  14. Purification, crystallization and preliminary X-ray characterization of Bacillus cereus arylamine N-acetyltransferase 3 [(BACCR)NAT3

    International Nuclear Information System (INIS)

    B. cereus arylamine N-acetyltransferase 3 was expressed, purified and crystallized. X-ray diffraction data were collected to 2.42 Å resolution and the crystals belonged to the monoclinic space group C121. Arylamine N-acetyltransferases (NATs) are xenobiotic metabolizing enzymes (XMEs) that catalyze the acetylation of arylamines. All functional NATs described to date possess a strictly conserved Cys-His-Asp catalytic triad. Here, the purification, crystallization and preliminary X-ray characterization of Bacillus cereus arylamine N-acetyltransferase 3 [(BACCR)NAT3], a putative NAT isoenzyme that possesses a unique catalytic triad containing a glutamate residue, is reported. The crystal diffracted to 2.42 Å resolution and belonged to the monoclinic space group C121, with unit-cell parameters a = 90.44, b = 44.52, c = 132.98 Å, β = 103.8°

  15. Isolation and Identification of a new Bacillus cereus strain and Characterization of its Neopullulanase

    Directory of Open Access Journals (Sweden)

    Soheila Davaeifar

    2015-03-01

    Full Text Available Identification and use of more efficient enzymes in the food and pharmaceutical industries is the focus of many researchers. The aim of this study was to search for a new bacterial strain capable of producing high levels of pullulanase applicable to biotechnology, the starch bioprocessing and food industries. A new pullulan hydrolyzing Bacillus strain was isolated and designated SDK2. Morphological and biochemical tests identified the strain as a putative Bacillus cereus strain, which was further characterized and confirmed through 16s rRNA sequencing, and was submitted to GeneBank, under the accession number FR6864500. Quantative analysis of the strain’s pullulanase activity was carried out by the Dintrosalicyclic (DNS acid-based assay. Thin layer chromatography (TLC of the culture supernatant, identified the extracellular pullulanase as neopullulanase. Effects of temperature and pH on pullulanase activity were also studied. The optimum conditions for enzyme activity, as represented by 60o C and a pH of 7, resulted in an activity of 13.43 U/ml, which is much higher than some of the previously reported activities. However, growth of B. cereus SDK2 was also observed at a pH range of 5 to 10, and temperatures of 30 oC to 50 oC. The effect of metal ions and reagents, such as Mg+2, Ca+2, Zn+2, Cu+2, Fe+2, Ni+2 on enzyme activity showed that Ca+2 ions increased pullulan activity, whereas the other ions and reagents inhibited pullulanase activity. The ability of B. cereus SDK2 to produce high levels of neopullulanase stable at 60 oC that can generate panose from pullulan, make this newly isolated strain a valuable source of debranching enzyme for biotechnology, the starch bioprocess and medical industries.

  16. Communication of 1 October 2009 received from the Resident Representative of Hungary to the Agency on behalf of the participating Governments of the Nuclear Suppliers Group

    International Nuclear Information System (INIS)

    The Director General has received a letter dated 1 October 2009 from the Resident Representative of Hungary to the Agency on behalf of the Participating Governments of the Nuclear Suppliers Group.1 Attached to this letter is an updated version of a paper entitled 'The Nuclear Suppliers Group: Its Origins, Role and Activities. The original version of this paper was issued as INFCIRC/539 on 15 September 1997: revisions were issued on 17 April 2000, 16 September 2003 and 30 May 2005. As requested in the letter, the revised version of the paper, attached hereto, is being circulated to Member States of the IAEA

  17. Produktion von poly- und monoklonalen Antikörpern gegen Staphylococcus aureus, Bacillus cereus und Sporen von Bacillus cereus zur Entwicklung eines bioaffinitätschromatographischen Schnellnachweises

    OpenAIRE

    Wiescher, Fabian Mathias Moritz

    2013-01-01

    Produktion von poly- und monoklonalen Antikörpern gegen Staphylococcus aureus, Bacillus cereus und Sporen von Bacillus cereus in Mäusen und Kaninchen, Charakterisierung der Antikörper mittels Enzym-Immunoassays, Immunfluoreszenz, Immunoblots etc., Einsatz der Antikörper in einem bioaffinitätschromatographischen Schnellnachweis mittels monolithischem Säulenmaterial.

  18. YwdL in Bacillus cereus: its role in germination and exosporium structure.

    Directory of Open Access Journals (Sweden)

    Cassandra Terry

    Full Text Available In members of the Bacillus cereus group the outermost layer of the spore is the exosporium, which interacts with hosts and the environment. Efforts have been made to identify proteins of the exosporium but only a few have so far been characterised and their role in determining spore architecture and spore function is still poorly understood. We have characterised the exosporium protein, YwdL. ΔywdL spores have a more fragile exosporium, subject to damage on repeated freeze-thawing, although there is no evidence of altered resistance properties, and coats appear intact. Immunogold labelling and Western blotting with anti-YwdL antibodies identified YwdL to be located exclusively on the inner surface of the exosporium of B. cereus and B. thuringiensis. We conclude that YwdL is important for formation of a robust exosporium but is not required to maintain the crystalline assembly within the basal layer or for attachment of the hairy nap structure. ΔywdL spores are unable to germinate in response to CaDPA, and have altered germination properties, a phenotype that confirms the expected defect in localization of the cortex lytic enzyme CwlJ in the coat.

  19. Naphthalene degradation and biosurfactant activity by Bacillus cereus 28BN

    Energy Technology Data Exchange (ETDEWEB)

    Tuleva, B.; Christova, N. [Inst. of Microbiology, Bulgarian Academy of Sciences, Sofia (Bulgaria); Jordanov, B.; Nikolova-Damyanova, B. [Inst. of Organic Chemistry, Sofia (Bulgaria); Petrov, P. [National Center of Infectious and Parasitic Diseases, Sofia (Bulgaria)

    2005-08-01

    Biosurfactant activity and naphthalene degradation by a new strain identified as Bacillus cereus 28BN were studied. The strain grew well and produced effective biosurfactants in the presence of n-alkanes, naphthalene, crude oil and vegetable oils. The biosurfactants were detected by the surface tension lowering of the medium, thin layer chromatography and infrared spectra analysis. With (2%) naphthalene as the sole carbon source, high levels of rhamnolipids at a concentration of 2.3 g l{sup -1} were determined in the stationary growth. After 20 d of incubation 72 {+-} 4% of the initial naphthalene was degraded. This is the first report for a Bacillus cereus rhamnolipid producing strain that utilized naphthalene under aerobic conditions. The strain looks promising for application in environmental technologies. (orig.)

  20. DNA fingerprinting of Bacillus cereus from diverse sources by restriction fragment length polymorphism analysis

    OpenAIRE

    Swarnakaran Hemalatha; Narasimhan Banu

    2010-01-01

    Bacillus cereus is an opportunistic pathogen causing food poisoning manifested by diarrhoeal or emetic syndrome. It is closely related to animal and human pathogens Bacillus anthracis and the insect pathogen Bacillus thuringiensis. In the present study, antibiotic resistance, heavy metal tolerance & molecular typing of Bacillus cereus from diverse sources such as soil, sewage water, air, fresh water, sea water and milk were studied. Bacillus cereus resistant to Penicillin (10 units/ml) an...

  1. Bacteriophage PBC1 and Its Endolysin as an Antimicrobial Agent against Bacillus cereus

    OpenAIRE

    Kong, Minsuk; Ryu, Sangryeol

    2015-01-01

    Bacillus cereus is an opportunistic human pathogen responsible for food poisoning and other, nongastrointestinal infections. Due to the emergence of multidrug-resistant B. cereus strains, the demand for alternative therapeutic options is increasing. To address these problems, we isolated and characterized a Siphoviridae virulent phage, PBC1, and its lytic enzymes. PBC1 showed a very narrow host range, infecting only 1 of 22 B. cereus strains. Phylogenetic analysis based on the major capsid pr...

  2. Meningitis due to Bacillus cereus: A Case Report and Review of the Literature

    OpenAIRE

    Stevens, Michael P.; Kara Elam; Gonzalo Bearman

    2012-01-01

    Bacillus cereus is infrequently associated with invasive central nervous system (CNS) disease. Infection is associated with conditions that lead to reduced host immunity and provide direct access to the CNS, such as spinal anesthesia and ventricular tubes and shunts. A case of ventriculitis secondary to B cereus in a patient receiving intrathecal chemotherapy is reported, along with a review of the current literature. B cereus can colonize medical devices, thus posing a risk for invasive dise...

  3. Respiratory systems of the Bacillus cereus mother cell and forespore.

    OpenAIRE

    Escamilla, J E; R. Ramírez; Del-Arenal, P; Aranda, A.

    1986-01-01

    The respiratory systems of the mother cells and forespores of Bacillus cereus were compared throughout the maturation stages (III to VI) of sporulation. The results indicated that both cell compartments contain the same assortment of oxidoreductases and cytochromes. However membrane fractions from young forespores were clearly distinct from those of the mother cell, i.e., lower content of cytochrome aa3, lower cytochrome c oxidase activity, higher concentration of cytochrome o, and a lower se...

  4. Biodegradation of Eugenol by Bacillus Cereus Strain PN24

    OpenAIRE

    Kadakol, Jagannath C.; Kamanavalli, Chandrappa M.

    2010-01-01

    Bacillus cereus PN24 was isolated from soil by a conventional enrichment culture method using eugenol as a sole source of carbon and energy. The organism also utilized eugenol, 4-vinyl guaiacol, vanillin, vanillic acid and protocatechuic acid as growth substrates. The organism degraded eugenol to protocatechuic acid, which was further metabolized by a β-ketoadipate pathway. On the other hand, the intermediate of the eugenol-degrading pathway, such as ferulic acid was not detected in the cultu...

  5. Genotypic Diversity among Bacillus cereus and Bacillus thuringiensis Strains

    OpenAIRE

    Carlson, Cathrine Rein; Caugant, Dominique A; Kolstø, Anne-Brit

    1994-01-01

    Twenty-four strains of Bacillus cereus were analyzed by pulsed-field gel electrophoresis (PFGE) and compared with 12 Bacillus thuringiensis strains. In addition, the 36 strains were examined for variation in 15 chromosomal genes encoding enzymes (by multilocus enzyme electrophoresis [MEE]). The genome of each strain had a distinct NotI restriction enzyme digestion profile by PFGE, and the 36 strains could be assigned to 27 multilocus genotypes by MEE. However, neither PFGE nor MEE analysis co...

  6. Production of Alpha Amylase by Bacillus cereus in Submerged Fermentation

    Directory of Open Access Journals (Sweden)

    Helen H. Raplong

    2014-09-01

    Full Text Available Microorganisms have the ability to secrete enzymes when they are grown in the presence of certain substrates. Amylases are among the most important industrial enzymes and are of great significance in biotechnological studies. Bacteria belonging to the genus Bacillus were isolated using mannitol egg yolk polymyxin B (MYP agar a highly selective media for Bacillus cereus isolation. The isolates were tested for α-amylase production on nutrient agar supplemented with starch and in submerged fermentation. The bacteria isolated and identified (using the Microgen Bacillus identification kit were all Bacillus cereus and SB2 had the largest zone of hydrolysis of 12mm on nutrient agar supplemented with starch as well as the highest enzyme activity of 1.62U/ml. Amylase activity of 2.56U/ml was obtained after 24 hours incubation in submerged fermentation. When amylase enzyme production parameters where optimized, maximum amylase activity was obtained at a pH of 6.5, temperature of 350C, incubation time of 24 hours and 4% inoculums concentration. Bacillus cereus SB2 is a potential isolate for alpha-amylase production with soluble starch as the sole carbon source in submerged fermentation.

  7. Laundry detergent compatibility of the alkaline protease from Bacillus cereus.

    Science.gov (United States)

    Banik, Rathindra Mohan; Prakash, Monika

    2004-01-01

    The endogenous protease activity in various commercially available laundry detergents of international companies was studied. The maximum protease activity was found at 50 degrees C in pH range 10.5-11.0 in all the tested laundry detergents. The endogenous protease activity in the tested detergents retained up to 70% on incubation at 40 degrees C for 1 h, whereas less than 30% activity was only found on incubation at 50 degrees C for 1 h. The alkaline protease from an alkalophilic strain of Bacillus cereus was studied for its compatibility in commercial detergents. The cell free fermented broth from shake flask culture of the organism showed maximum activity at pH 10.5 and 50 degrees C. The protease from B. cereus showed much higher residual activity (more than 80%) on incubation with laundry detergents at 50 degrees C for 1 h or longer. The protease enzyme from B. cereus was found to be superior over the endogenous proteases present in the tested commercial laundry detergents in comparison to the enzyme stability during the washing at higher temperature, e.g., 40-50 degrees C. PMID:15293947

  8. Occurrence and characterization of toxigenic Bacillus cereus in food and infant feces

    Institute of Scientific and Technical Information of China (English)

    Sameer; Rushdi; Organji; Hussein; Hasan; Abulreesh; Khaled; Elbanna; Gamal; Ebrahim; Haridy; Osman; Manal; Khider

    2015-01-01

    Objective: To investigate the true incidence of Bacillus cereus(B. cereus) in food and children diarrhea cases. Methods: A total of 110 samples of various dairy products such as raw milk, long life pasteurized milk, yoghurt and infant powdered milk formulas, raw rice, and feces were examined for the presence of B. cereus by selective plating on mannitol-egg-yolk-polymyxin agar. Confirmation of B. cereus was carried out by biochemical tests and PCR. Identification of non-B. cereus isolates was carried out by 16 S r DNA sequencing. Antimicrobial susceptibility was done by disk diffusion method.Results: Overall 35 samples(31.8%, n = 110) yielded Bacillus-like growth. Of which 19 samples(54.28%) were positive for B. cereus. All isolates were positive for enterotoxin production. No psychrotolerant B. cereus strains were detected in all samples. All B. cereus isolates were resistant to penicillin G, but susceptible to vancomycin, erythromycin and clindamycin. Conclusions: The results of this study confirm the importance of including B. cereus in disease control and prevention programs, as well as in routine clinical and food quality control laboratories in both Saudi Arabia and Egypt.

  9. Characterization and Metal Detoxification Potential of Moderately Thermophilic Bacillus cereus from Geothermal Springs of Himalaya

    OpenAIRE

    Aslam Khan Ghalib; Muhammad Yasin; Muhammad Faisal

    2014-01-01

    Two thermophilic Bacillus cereus strains (B. cereus-TA2 and B. cereus-TA4) used in the present study were isolated from the geothermal spring of Hunza valley, Gilgit, Pakistan. They showed the ability to withstand and grow at high temperature (85°C). Both these strains could resist multiple metals (copper, cadmium, mercury, manganese, zinc, arsenic, chromium and selenium). Strain B. cereus-TA4 reduced Cr (VI) at pH 5.0 to 9.0 but maximum reduction (83%) was observed at pH 7.0 after 48 h when ...

  10. Production and Characterization of Monoclonal Antibodies against Vegetative Cells of Bacillus cereus

    OpenAIRE

    Charni, Nadine; Perissol, Claude; Le Petit, Jean; Rugani, Nathalie

    2000-01-01

    Two monoclonal antibodies (MAbs) against Bacillus cereus were produced. The MAbs (8D3 and 9B7) were selected by enzyme-linked immunosorbent assay for their reactivity with B. cereus vegetative cells. They reacted with B. cereus vegetative cells while failing to recognize B. cereus spores. Immunoblotting revealed that MAb 8D3 recognized a 22-kDa antigen, while MAb 9B7 recognized two antigens with molecular masses of approximately 58 and 62 kDa. The use of MAbs 8D3 and 9B7 in combination to dev...

  11. Bacillus cereus bacteremia and multiple brain abscesses during acute lymphoblastic leukemia induction therapy.

    Science.gov (United States)

    Hansford, Jordan R; Phillips, Marianne; Cole, Catherine; Francis, Joshua; Blyth, Christopher C; Gottardo, Nicholas G

    2014-04-01

    Bacillus cereus can cause serious infections in immunosuppressed patients. This population may be susceptible to B. cereus pneumonia, bacteremia, cellulitis, and rarely cerebral abscess. Here we report an 8-year-old boy undergoing induction therapy for acute lymphoblastic leukemia who developed multifocal B. cereus cerebral abscesses, highlighting the propensity for B. cereus to develop cerebral abscesses. A review of the literature over the past 25 years identified another 11 cases (3 children and 8 adults) of B. cereus cerebral abscess in patients undergoing cancer therapy. B. cereus cerebral abscesses were associated with a high mortality rate (42%) and significant morbidity. Notably, B. cereus bacteremia with concomitant cerebral abscess was associated with induction chemotherapy for acute leukemia in both children and adults (10 of 12 case reports). Our case report and review of the literature highlights the propensity for B. cereus to develop cerebral abscess(es). Therefore, early consideration for neuroimaging should be given for any neutropenic cancer patient identified with B. cereus bacteremia, in particular those with acute leukemia during induction therapy. PMID:23619116

  12. Assessment of hydrophobicity and roughness of stainless steel adhered by an isolate of Bacillus cereus from a dairy plant

    OpenAIRE

    Patrícia Campos Bernardes; Nélio José de Andrade; Sukarno Olavo Ferreira; João Paulo Natalino de Sá; Emiliane Andrade Araújo; Deyse Maria Zanom Delatorre; Lívia Maria Pinheiro Luiz

    2010-01-01

    The interaction between the surface of stainless steel and Bacillus cereus was studied in terms of the characteristics of interfacial interaction determined from the measurement of the contact angle of the surface of B. cereus and stainless steel in the presence or absence of B. cereus adherence. The microtopographies and the roughness of the surface of stainless steel and stainless steel adhered by B. cereus were evaluated with the help of atomic force microscopy and perfilometry. The strain...

  13. Genetic relationships between sympatric populations of Bacillus cereus and Bacillus thuringiensis, as revealed by rep-PCR genomic fingerprinting

    OpenAIRE

    Ana Paula S Peruca; Vilas-Bôas, Gislayne T.; OMN Arantes

    2008-01-01

    The bacterial strain Bacillus cereus is closely related to Bacillus thuringiensis, although any genetic relationship between the two strains is still in debate. Using rep-PCR genomic fingerprinting, we established the genetic relationships between Brazilian sympatric populations of B. cereus and B. thuringiensis simultaneously collected from two geographically separate sites. We observed the formation of both B. thuringiensis and B. cereus clusters, as well as strains of B. cereus that are mo...

  14. Effect of hydrolyzed copra meal separately or in combination with Bacillus cereus var. toyoi on growth performance of broiler chickens

    Directory of Open Access Journals (Sweden)

    Karina Ferreira Duarte

    2014-09-01

    Full Text Available The effects of mannanase-hydrolyzed copra meal (MCM and MCM + probiotic Bacillus cereus var. toyoi (TY on growth performance and gut morphometry of broiler chickens were investigated. A total of 1120-one-day-old Cobb chicks were distributed in a completely randomized design with 4 diet treatment groups. Dietary treatments were (1 negative control; (2 positive control (avilamycin 10 ppm; (3 0.1% MCM for basal diets (4 0.1% MCM + 0.05% TY. The best feed conversion ratio (FCR, body weight (BW, productivity index (PI was obtained with 0.1% MCM + 0.05% TY at 42 days of age. With regard to productivity index, every supplementation group had a better rate when compared to that in negative group. Although 0.1% MCM supplemented alone is worse than positive group, it reveals a significantly better value than when it is combined with 0.1% MCM and 0.05% TY. The combination of mannanase-hydrolyzed copra meal with Bacillus cereus var. toyoi improved broiler performance and duodenum and jejunum mucous morphometry, when compared to the negative, positive and 0.1% MCM alone supplementation groups. The combination of MCM and TY probiotics is capable of improving intestinal morphology by behaving like a good growth promoter, with possibility of being an alternative to antibiotics.

  15. Concerted action of sphingomyelinase and non-hemolytic enterotoxin in pathogenic Bacillus cereus.

    Directory of Open Access Journals (Sweden)

    Viktoria M Doll

    Full Text Available Bacillus cereus causes food poisoning and serious non-gastrointestinal-tract infections. Non-hemolytic enterotoxin (Nhe, which is present in most B. cereus strains, is considered to be one of the main virulence factors. However, a B. cereus ΔnheBC mutant strain lacking Nhe is still cytotoxic to intestinal epithelial cells. In a screen for additional cytotoxic factors using an in vitro model for polarized colon epithelial cells we identified B. cereus sphingomyelinase (SMase as a strong inducer of epithelial cell death. Using single and double deletion mutants of sph, the gene encoding for SMase, and nheBC in B. cereus we demonstrated that SMase is an important factor for B. cereus cytotoxicity in vitro and pathogenicity in vivo. SMase substantially complemented Nhe induced cytotoxicity in vitro. In addition, SMase but not Nhe contributed significantly to the mortality rate of larvae in vivo in the insect model Galleria mellonella. Our study suggests that the role of B. cereus SMase as a secreted virulence factor for in vivo pathogenesis has been underestimated and that Nhe and SMase complement each other significantly to cause full B. cereus virulence hence disease formation.

  16. Persistent Bacillus cereus Bacteremia in 3 Persons Who Inject Drugs, San Diego, California, USA.

    Science.gov (United States)

    Schaefer, Gabrielle; Campbell, Wesley; Jenks, Jeffrey; Beesley, Cari; Katsivas, Theodoros; Hoffmaster, Alex; Mehta, Sanjay R; Reed, Sharon

    2016-09-01

    Bacillus cereus is typically considered a blood culture contaminant; however, its presence in blood cultures can indicate true bacteremia. We report 4 episodes of B. cereus bacteremia in 3 persons who inject drugs. Multilocus sequence typing showed that the temporally associated infections were caused by unrelated clones. PMID:27533890

  17. Draft Genome Sequence of Bacillus cereus Strain F, Isolated from Ancient Permafrost

    OpenAIRE

    Brenner, Evgeniy V.; Brouchkov, Anatoli V.; Kurilshikov, Alexander M.; Griva, Gennady I.; Kashuba, Elena; Kashuba, Vladimir I.; Melefors, O; Repin, Vladimir E.; Melnikov, Vladimir P.; Vlassov, Valentin V

    2013-01-01

    Bacillus cereus strain F was isolated and cultured from a sample of permafrost, aged presumably about 3 million years, on the Mammoth Mountain (62°56′N, 133°59′E). These genome data provide the basis to investigate Bacillus cereus F, identified as a long-term survivor of the extremely cold and close environment.

  18. Native Valve Bacillus cereus Endocarditis in a Non-Intravenous-Drug-Abusing Patient

    OpenAIRE

    Thomas, Benjamin S.; Bankowski, Matthew J.; Lau, William K. K.

    2012-01-01

    Bacillus cereus is a rare cause of endocarditis, typically associated with intravenous drug abuse, rheumatic heart disease, prosthetic heart valves, pacemakers, or immunodeficiency. We present the first case of native valve Bacillus cereus endocarditis with no apparent risk factors. The patient had a fulminant course requiring emergent valve replacement.

  19. A new chemically defined medium for the growth and sporulation of Bacillus cereus strains in anaerobiosis

    OpenAIRE

    Abbas, Amina aïcha; Tichit-Planchon, Stella; Jobin, Michel

    2014-01-01

    A new chemically defined liquid medium, MODS, was developed for the aerobic growth and anaerobic growth and sporulation of Bacillus cereus strains. The comparison of sporulation capacity of 18 strains of B. cereus has shown effective growth and spore production in anaerobiosis.

  20. Detection and expression of enterotoxin genes in plant-associated strains of Bacillus cereus

    Science.gov (United States)

    Bacillus cereus is an environmental microbe that commonly inhabits plants and soil. Twenty five plant-associated B. cereus isolates were obtained from apple, cacao, tomato, and potato. The isolates were screened for the presence and expression of enterotoxin B (BcET) components of the nonhemolytic e...

  1. Plant compounds enhance assay sensitivity for detection of active bacillus cereus toxin

    Science.gov (United States)

    Bacillus cereus is an important food pathogen, producing emetic and diarrheal syndromes, the latter mediated by enterotoxins. It has been estimated that there are 84,000 cases of B. cereus food poisoning in the US each year, with an annual cost of USD 36 million. The ability to sensitively trace and...

  2. Purification, crystallization and preliminary X-ray characterization of Bacillus cereus arylamine N-acetyltransferase 3 [(BACCR)NAT3].

    Science.gov (United States)

    Kubiak, Xavier; Pluvinage, Benjamin; Li de la Sierra-Gallay, Inès; Weber, Patrick; Haouz, Ahmed; Dupret, Jean-Marie; Rodrigues-Lima, Fernando

    2012-02-01

    Arylamine N-acetyltransferases (NATs) are xenobiotic metabolizing enzymes (XMEs) that catalyze the acetylation of arylamines. All functional NATs described to date possess a strictly conserved Cys-His-Asp catalytic triad. Here, the purification, crystallization and preliminary X-ray characterization of Bacillus cereus arylamine N-acetyltransferase 3 [(BACCR)NAT3], a putative NAT isoenzyme that possesses a unique catalytic triad containing a glutamate residue, is reported. The crystal diffracted to 2.42 Å resolution and belonged to the monoclinic space group C121, with unit-cell parameters a = 90.44, b = 44.52, c = 132.98 Å, β = 103.8°. PMID:22297998

  3. Radiosensitization of Bacillus cereus spores in minced meat treated with cinnamaldehyde

    Science.gov (United States)

    Ayari, S.; Dussault, D.; Jerbi, T.; Hamdi, M.; Lacroix, M.

    2012-08-01

    Minced meat beef inoculated with Bacillus cereus spores was treated with four essential oil constituents. The active compounds were sprayed separately onto the meat in order to determine the concentration needed to reduce by 1 log the population of B. cereus spores. Cinnamaldehyde was the best antimicrobial compound selected. It was mixed with ascorbic acid and/or sodium pyrophosphate decahydrate and tested for its efficiency to increase the relative radiation sensitivity (RRS) of B. cereus spores in minced meat packed under air. Results demonstrated that the radiation treatment in presence of the cinnamaldehyde and sodium phosphate decahydrate increased the RRS of B. cereus spores by two fold. The study revealed also that the irradiation of raw beef meat pre-treated with cinnamaldehyde produced an inhibition of the growth of B. cereus count during refrigerated storage. This technology seems to be compatible with industrial meat processing.

  4. Radiosensitization of Bacillus cereus spores in minced meat treated with cinnamaldehyde

    International Nuclear Information System (INIS)

    Minced meat beef inoculated with Bacillus cereus spores was treated with four essential oil constituents. The active compounds were sprayed separately onto the meat in order to determine the concentration needed to reduce by 1 log the population of B. cereus spores. Cinnamaldehyde was the best antimicrobial compound selected. It was mixed with ascorbic acid and/or sodium pyrophosphate decahydrate and tested for its efficiency to increase the relative radiation sensitivity (RRS) of B. cereus spores in minced meat packed under air. Results demonstrated that the radiation treatment in presence of the cinnamaldehyde and sodium phosphate decahydrate increased the RRS of B. cereus spores by two fold. The study revealed also that the irradiation of raw beef meat pre-treated with cinnamaldehyde produced an inhibition of the growth of B. cereus count during refrigerated storage. This technology seems to be compatible with industrial meat processing.

  5. The PlcR virulence regulon of Bacillus cereus.

    Directory of Open Access Journals (Sweden)

    Michel Gohar

    Full Text Available PlcR is a Bacillus cereus transcriptional regulator, which activates gene expression by binding to a nucleotidic sequence called the 'PlcR box'. To build a list of all genes included in the PlcR regulon, a consensus sequence was identified by directed mutagenesis. The reference strain ATCC14579 sequenced genome was searched for occurrences of this consensus sequence to produce a virtual regulon. PlcR control of these genes was confirmed by comparing gene expression in the reference strain and its isogenic Delta-plcR strain using DNA microarrays, lacZ fusions and proteomics methods. The resulting list included 45 genes controlled by 28 PlcR boxes. Forty of the PlcR controlled proteins were exported, of which 22 were secreted in the extracellular medium and 18 were bound or attached to cell wall structures (membrane or peptidoglycan layer. The functions of these proteins were related to food supply (phospholipases, proteases, toxins, cell protection (bacteriocins, toxins, transporters, cell wall biogenesis and environment-sensing (two-component sensors, chemotaxis proteins, GGDEF family regulators. Four genes coded for cytoplasmic regulators. The PlcR regulon appears to integrate a large range of environmental signals, including food deprivation and self cell-density, and regulate the transcription of genes designed to overcome obstacles that hinder B. cereus growth within the host: food supply, host barriers, host immune defenses, and competition with other bacterial species. PlcR appears to be a key component in the efficient adaptation of B. cereus to its host environment.

  6. Bacillus cereus un patógeno importante en el control microbiológico de los alimentos / Bacillus cereus an important pathogen the microbiological control of food

    Directory of Open Access Journals (Sweden)

    Jennifer Sánchez

    2016-05-01

    Full Text Available Resumen Bacillus cereus es una bacteria genéticamente diversa que se encuentra comúnmente en el ambiente. Contamina los alimentos afectando la salud humana, al ingerir el microorganismo y/o sus toxinas, la emética o las enterotoxinas. En Colombia son escasos los reportes de intoxicación por B. cereus y se estima que hay un gran subregistro. Por lo anterior, se recomienda aumentar la vigilancia de este patógeno y realizar estudios sobre aspectos relevantes que permitan aplicar medidas de control para disminuir las intoxicaciones por B. cereus. El objetivo de esta revisión bibliográfica es presentar información actualizada sobre B. cereus, que incluye aspectos de su biología, taxonomía, toxinas, alimentos que contamina y metodologías para detectar, prevenir y controlar este microorganismo. La información presentada es de utilidad para el público en general, especialmente personas vinculadas al sector de alimentos, inocuidad alimentaria y control de procesos. / Abstract Bacillus cereus is a genetically diverse bacterium commonly found in the environment. It contaminates food, thus affecting human health upon ingestion of the microorganism and/or its toxins, the emetic or enterotoxins. In Colombia, reports of intoxication by B. cereus are scarce and under-registration is presumed. Because of this, it is recommended to increase surveillance of this pathogen and to develop studies on relevant aspects that allow the application of control measures to reduce intoxications by B. cereus. The aim of this review is to present current information on B. cereus, including aspects of its biology, taxonomy, toxins, food that it contaminates and methodologies for the detection, prevention and control of this microorganism. This information is useful for the general public, especially people involved with the food sector, food safety and process control.

  7. Arthromitus (Bacillus cereus) symbionts in the cockroach Blaberus giganteus: dietary influences on bacterial development and population density

    Science.gov (United States)

    Feinberg, L.; Jorgensen, J.; Haselton, A.; Pitt, A.; Rudner, R.; Margulis, L.

    1999-01-01

    The filamentous spore-forming bacterium Arthromitus, discovered in termites, millipedes, sow bugs and other soil-dwelling arthropods by Leidy (1850), is the intestinal stage of Bacillus cereus. We extend the range of Arthromitus habitats to include the hindgut of Blaberus giganteus, the large tropical American cockroach. The occurrence and morphology of the intestinal form of the bacillus were compared in individual cockroaches (n=24) placed on four different diet regimes: diurnally maintained insects fed (1) dog food, (2) soy protein only, (3)purified cellulose only, and (4) a dog food-fed group maintained in continuous darkness. Food quality exerted strong influence on population densities and developmental stages of the filamentous bacterium and on fecal pellet composition. The most dramatic rise in Arthromitus populations, defined as the spore-forming filament intestinal stage, occurred in adult cockroaches kept in the dark on a dog food diet. Limited intake of cellulose or protein alone reduced both the frequency of Arthromitus filaments and the rate of weight gain of the insects. Spores isolated from termites, sow bugs, cockroaches and moths, grown on various hard surfaces display a branching mobility and resistance to antibiotics characteristic to group I Bacilli whose members include B. cereus, B. circulans, B. alvei and B. macerans. DNA isolated from pure cultures of these bacilli taken from the guts of Blaberus giganteus (cockroach), Junonia coenia (moth), Porcellio scaber (sow bug) and Cryptotermes brevis (termite) and subjected to Southern hybridization with a 23S-5S B. subtilis ribosomal sequence probe verified that they are indistinguishable from laboratory strains of Bacillus cereus.

  8. The Arthromitus stage of Bacillus cereus: intestinal symbionts of animals

    Science.gov (United States)

    Margulis, L.; Jorgensen, J. Z.; Dolan, S.; Kolchinsky, R.; Rainey, F. A.; Lo, S. C.

    1998-01-01

    In the guts of more than 25 species of arthropods we observed filaments containing refractile inclusions previously discovered and named "Arthromitus" in 1849 by Joseph Leidy [Leidy, J. (1849) Proc. Acad. Nat. Sci. Philadelphia 4, 225-233]. We cultivated these microbes from boiled intestines of 10 different species of surface-cleaned soil insects and isopod crustaceans. Literature review and these observations lead us to conclude that Arthromitus are spore-forming, variably motile, cultivable bacilli. As long rod-shaped bacteria, they lose their flagella, attach by fibers or fuzz to the intestinal epithelium, grow filamentously, and sporulate from their distal ends. When these organisms are incubated in culture, their life history stages are accelerated by light and inhibited by anoxia. Characterization of new Arthromitus isolates from digestive tracts of common sow bugs (Porcellio scaber), roaches (Gromphodorhina portentosa, Blaberus giganteus) and termites (Cryptotermes brevis, Kalotermes flavicollis) identifies these flagellated, spore-forming symbionts as a Bacillus sp. Complete sequencing of the 16S rRNA gene from four isolates (two sow bug, one hissing roach, one death's head roach) confirms these as the low-G+C Gram-positive eubacterium Bacillus cereus. We suggest that B. cereus and its close relatives, easily isolated from soil and grown on nutrient agar, enjoy filamentous growth in moist nutrient-rich intestines of healthy arthropods and similar habitats.

  9. Disinfection of Preexisting Contamination of BACILLUS CEREUS on Stainless Steel when Using Glycoconjugate Solution

    Science.gov (United States)

    Pavan, Casey; Tarasenko, Olga

    2011-06-01

    Stainless steel is ubiquitous in our modern world, however it can become contaminated. This can endanger our health. The aim of our study is to disinfect stainless steel using Bacillus cereus as a model organism. Bacillus cereus is a microbe that is ubiquitous in nature, specifically soil. B. cereus is known to cause illness in humans. To prevent this, we propose to use a glycoconjugate solution (GS) for disinfection of stainless steel after it is contamination by B. cereus spores. In this study, two GS (9, 10) were tested for disinfection effectiveness on B. cereus spores on the surface of stainless steel foil (AISI-Series 200/300/400, THERMA-FOIL, Dayville, CT 0241). The disinfection rate of each GS was assessed by exposing the steel surface to B. cereus spores first and allowing them to settle for 24 hours. GS was used to treat the contaminated surface. The steel is washed and the resulting solution is plated on tryptic soy agar (TSA) plates. The GS with the fewest colony forming unit (CFU) formed on TSA is determined to be the most efficient during disinfection. Results show that both GS demonstrate a strong ability to disinfect B. cereus spores. Between the two, GS 9 shows the highest disinfection efficacy by killing approximately 99.5% of spores. This is a drastic improvement over the 0-20% disinfection of the control. Based on this we find that studied GS do have the capacity to act as a disinfectant on stainless steel.

  10. Disinfection of preexisting contamination of bacillus cereus on stainless steel when using glycoconjugate solution

    International Nuclear Information System (INIS)

    Stainless steel is ubiquitous in our modern world, however it can become contaminated. This can endanger our health. The aim of our study is to disinfect stainless steel using Bacillus cereus as a model organism. Bacillus cereus is a microbe that is ubiquitous in nature, specifically soil. B. cereus is known to cause illness in humans. To prevent this, we propose to use a glycoconjugate solution (GS) for disinfection of stainless steel after it is contamination by B. cereus spores. In this study, two GS (9, 10) were tested for disinfection effectiveness on B. cereus spores on the surface of stainless steel foil (AISI-Series 200/300/400, THERMA-FOIL, Dayville, CT 0241). The disinfection rate of each GS was assessed by exposing the steel surface to B. cereus spores first and allowing them to settle for 24 hours. GS was used to treat the contaminated surface. The steel is washed and the resulting solution is plated on tryptic soy agar (TSA) plates. The GS with the fewest colony forming unit (CFU) formed on TSA is determined to be the most efficient during disinfection. Results show that both GS demonstrate a strong ability to disinfect B. cereus spores. Between the two, GS 9 shows the highest disinfection efficacy by killing approximately 99.5% of spores. This is a drastic improvement over the 0-20% disinfection of the control. Based on this we find that studied GS do have the capacity to act as a disinfectant on stainless steel.

  11. Genetic diversity of clinical isolates of Bacillus cereus using multilocus sequence typing

    Directory of Open Access Journals (Sweden)

    Pruckler James M

    2008-11-01

    Full Text Available Abstract Background Bacillus cereus is most commonly associated with foodborne illness (diarrheal and emetic but is also an opportunistic pathogen that can cause severe and fatal infections. Several multilocus sequence typing (MLST schemes have recently been developed to genotype B. cereus and analysis has suggested a clonal or weakly clonal population structure for B. cereus and its close relatives B. anthracis and B. thuringiensis. In this study we used MLST to determine if B. cereus isolates associated with illnesses of varying severity (e.g., severe, systemic vs. gastrointestinal (GI illness were clonal or formed clonal complexes. Results A retrospective analysis of 55 clinical B. cereus isolates submitted to the Centers for Disease Control and Prevention between 1954 and 2004 was conducted. Clinical isolates from severe infections (n = 27, gastrointestinal (GI illness (n = 18, and associated isolates from food (n = 10 were selected for analysis using MLST. The 55 isolates were diverse and comprised 38 sequence types (ST in two distinct clades. Of the 27 isolates associated with serious illness, 13 clustered in clade 1 while 14 were in clade 2. Isolates associated with GI illness were also found throughout clades 1 and 2, while no isolates in this study belonged to clade 3. All the isolates from this study belonging to the clade 1/cereus III lineage were associated with severe disease while isolates belonging to clade1/cereus II contained isolates primarily associated with severe disease and emetic illness. Only three STs were observed more than once for epidemiologically distinct isolates. Conclusion STs of clinical B. cereus isolates were phylogenetically diverse and distributed among two of three previously described clades. Greater numbers of strains will need to be analyzed to confirm if specific lineages or clonal complexes are more likely to contain clinical isolates or be associated with specific illness, similar to B. anthracis and

  12. Biomineralization of Pb(II) into Pb-hydroxyapatite induced by Bacillus cereus 12-2 isolated from Lead-Zinc mine tailings.

    Science.gov (United States)

    Chen, Zhi; Pan, Xiaohong; Chen, Hui; Guan, Xiong; Lin, Zhang

    2016-01-15

    The remediation of Pb(II) through biomineralization is rergarded as a promising technique as well as an interesting phenomenon for transforming heavy metals from mobile species into very stable minerals in the environment. Studies are well needed for in-depth understanding the mechanism of Pb(II) immobilized by bacteria. In the present study, we investigated the uptake and biomineralization of Pb(II) using Bacillus cereus 12-2 isolated from lead-zinc mine tailings. The maximum Pb(II) uptake capacity of B. cereus 12-2 was 340 mg/g at pH 3.0. Zeta potential analyses and selective passivation experiments demonstrated that electrostatic attraction was the main force driving the uptake of Pb(II), while the carboxyl, amide and phosphate functional groups of the bacteria provided the binding sites for immobilizing Pb(II). XRD and TEM investigation revealed that the Pb(II) loaded on bacteria could be stepwise transformed into rod-shaped Ca2.5Pb7.5(OH)2(PO4)6 nanocrystal. Combined with protein denaturalization experiments, we proposed that the biomineralization of Pb(II) possibly consisted of two steps: (1) Rapid biosorption of Pb(II) on B. cereus 12-2 through the synergy of electrostatic attraction, ionic exchange and chelating activity of functional groups; (2) enzyme-mediated mineral transformation from amorphous precipitate to rod-shaped crystalline minerals happening gradually inside the bacteria. PMID:26468754

  13. Life of the Aquifer: Improving Earth Science Education for Teachers and Students in High Schools of Under-represented Groups on the North Carolina Coastal Plain

    Science.gov (United States)

    Farley, M. B.; Phillips, P. L.; McBroom, R.

    2007-12-01

    Life of the Aquifer is a program to improve Earth Science education in local public high schools. Geologic awareness among the local population is low because southeastern N.C. are on the Coastal Plain where rocks are not visible. This has made instruction in Earth Science, now required in North Carolina high schools, difficult. Our approach is to use groundwater, source of local public water, as a theme to organize instruction in geology. More than 70% of the student population in Robeson County, a rural low-wealth area, is from groups under- represented in the geosciences (46% Native American and 31% African American). Linking basic concepts in geology to groundwater is a way to show how geology is real and affects society. Our project engages teachers and students in active inquiry of the functioning of local aquifers from recharge to groundwater production. Although data on water levels in the Black Creek aquifer have been collected, there has been little formal investigation because serious problems with groundwater have not been noted to date. Nonetheless, the hydraulic head of Black Creek Aquifer wells has been declining. We started by improving skills of local Earth Science teachers, because most have had no formal education in geology. The teachers attended workshops on basic geology, groundwater, and exercises based on local groundwater data. The workshops also included field trips to outcrops exposing the local aquifer, 100 km away in South Carolina. We also showed teachers how each topic addresses Competency Goals in the Standard Course of Study. By using our instructional modules, the teachers assist their students to develop spatial reasoning skills by analyzing maps. Student geologic knowledge is increased by learning how the components of a groundwater system form as a result of geologic processes and collecting data from the Internet on changes in groundwater systems over time. Our remaining implementation activity is installation of wells to

  14. The genome of a Bacillus isolate causing anthrax in chimpanzees combines chromosomal properties of B. cereus with B. anthracis virulence plasmids.

    Directory of Open Access Journals (Sweden)

    Silke R Klee

    Full Text Available Anthrax is a fatal disease caused by strains of Bacillus anthracis. Members of this monophyletic species are non motile and are all characterized by the presence of four prophages and a nonsense mutation in the plcR regulator gene. Here we report the complete genome sequence of a Bacillus strain isolated from a chimpanzee that had died with clinical symptoms of anthrax. Unlike classic B. anthracis, this strain was motile and lacked the four prohages and the nonsense mutation. Four replicons were identified, a chromosome and three plasmids. Comparative genome analysis revealed that the chromosome resembles those of non-B. anthracis members of the Bacillus cereus group, whereas two plasmids were identical to the anthrax virulence plasmids pXO1 and pXO2. The function of the newly discovered third plasmid with a length of 14 kbp is unknown. A detailed comparison of genomic loci encoding key features confirmed a higher similarity to B. thuringiensis serovar konkukian strain 97-27 and B. cereus E33L than to B. anthracis strains. For the first time we describe the sequence of an anthrax causing bacterium possessing both anthrax plasmids that apparently does not belong to the monophyletic group of all so far known B. anthracis strains and that differs in important diagnostic features. The data suggest that this bacterium has evolved from a B. cereus strain independently from the classic B. anthracis strains and established a B. anthracis lifestyle. Therefore we suggest to designate this isolate as "B. cereus variety (var. anthracis".

  15. Vaccine Protection against Bacillus cereus-Mediated Respiratory Anthrax-Like Disease in Mice

    OpenAIRE

    Oh, So-Young; Maier, Hannah; Schroeder, Jay; Richter, G. Stefan; Elli, Derek; Musser, James M.; Quenee, Lauriane E.; Missiakas, Dominique M.; Schneewind, Olaf

    2013-01-01

    Bacillus cereus strains harboring a pXO1-like virulence plasmid cause respiratory anthrax-like disease in humans, particularly in welders. We developed mouse models for intraperitoneal as well as aerosol challenge with spores of B. cereus G9241, harboring pBCXO1 and pBC218 virulence plasmids. Compared to wild-type B. cereus G9241, spores with a deletion of the pBCXO1-carried protective antigen gene (pagA1) were severely attenuated, whereas spores with a deletion of the pBC218-carried protecti...

  16. A cluster of Bacillus cereus bacteremia cases among injection drug users.

    Science.gov (United States)

    Benusic, Michael A; Press, Natasha M; Hoang, Linda Mn; Romney, Marc G

    2015-01-01

    Bacillus cereus is a ubiquitous spore-forming organism that is infrequently implicated in extraintestinal infections. The authors report three cases of B cereus bacteremia among injection drug users presenting within one month to an urban tertiary care hospital. Treatment with intravenous vancomycin was successful in all three cases. While temporal association suggested an outbreak, molecular studies of patient isolates using pulsed-field gel electrophoresis did not suggest a common source. A review of the association of B cereus infections with heroin use and treatment of this pathogen is provided. PMID:26015795

  17. Structural and biochemical characterization of the Bacillus cereus 3-hydroxyisobutyrate dehydrogenase.

    Science.gov (United States)

    Park, Sun Cheol; Kim, Pyeung-Hyeun; Lee, Geun-Shik; Kang, Seung Goo; Ko, Hyun-Jeong; Yoon, Sung-Il

    2016-06-01

    The 3-hydroxyisobutyrate dehydrogenase (HIBADH) family catalyzes the NAD(+)- or NADP(+)-dependent oxidation of various β-hydroxyacid substrates into their cognate semialdehydes for diverse metabolic pathways. Because HIBADH group members exhibit different substrate specificities, the substrate-recognition mode of each enzyme should be individually characterized. In the current study, we report the biochemical and structural analysis of a HIBADH group enzyme from Bacillus cereus (bcHIBADH). bcHIBADH mediates a dehydrogenation reaction on S-3-hydroxyisobutyrate substrate with high catalytic efficiency in an NAD(+)-dependent manner; it also oxidizes l-serine and 3-hydroxypropionate with lower activity. bcHIBADH consists of two domains and is further assembled into a functional dimer rather than a tetramer that has been commonly observed in other prokaryotic HIBADH group members. In the bcHIBADH structure, the interdomain cleft forms a putative active site and simultaneously accommodates both an NAD(+) cofactor and a substrate mimic. Our structure-based comparative analysis highlights structural motifs that are important in the cofactor and substrate recognition of the HIBADH group. PMID:27120461

  18. Representing dispositions

    Directory of Open Access Journals (Sweden)

    Röhl Johannes

    2011-08-01

    Full Text Available Abstract Dispositions and tendencies feature significantly in the biomedical domain and therefore in representations of knowledge of that domain. They are not only important for specific applications like an infectious disease ontology, but also as part of a general strategy for modelling knowledge about molecular interactions. But the task of representing dispositions in some formal ontological systems is fraught with several problems, which are partly due to the fact that Description Logics can only deal well with binary relations. The paper will discuss some of the results of the philosophical debate about dispositions, in order to see whether the formal relations needed to represent dispositions can be broken down to binary relations. Finally, we will discuss problems arising from the possibility of the absence of realizations, of multi-track or multi-trigger dispositions and offer suggestions on how to deal with them.

  19. Characterization of arabinogalactan-rich mucilage from Cereus triangularis cladodes.

    Science.gov (United States)

    Petera, B; Delattre, C; Pierre, G; Wadouachi, A; Elboutachfaiti, R; Engel, E; Poughon, L; Michaud, P; Fenoradosoa, T A

    2015-01-01

    Cereus triangularis (Cactaceae) is a cactus used in food decoction as a traditional medicine in the North region of Madagascar to reduce stomach ache and intestinal diseases. Hydrocolloids were sequentially extracted from its cladodes with a yield of 24% (240 mg/g based on dried cladodes powder). Structural analyses has revealed that this polysaccharide with a molecular mass of 8430,000g/mol was mainly composed of a galactan backbone of a (1 → 4) linked β-d-Galp residues probably substituted at position 3 by L-arabinofuranosyl residues. In vitro antioxidant activity of this arabinogalactan-rich fraction was detected and quantified by radical DPPH scavenging, hydroxyl radical scavenging, radical anion superoxide scavenging and reducing power method. PMID:25965496

  20. Cereus peruvianus (Koubo new cactus fruit for the world

    Directory of Open Access Journals (Sweden)

    Yosef Mizrahi

    2014-03-01

    Full Text Available Several different species of the columnar cacti of the genera Stenocereus and Pachycereus, were introduced into different semi-arid ecozones in Israel and most of these efforts were of disappointing outcomes, the only exception being the Cereus peruvianus (L. Miller,which bore plenty of fruits, some of them of good taste. The original seeds of this plant were obtained from the late Mr. Amram (Ron Kodish, who collected seeds from various private gardens in Southern California which bore fruits of reasonable qualities. The initial success of this species led us to initiate an intensive research study, and today it is already fruit-crop, marketed mainly in Israel under the name " Koubo" . This paper will describe our work of domestication of this new cactus fruit crop in Israel.

  1. Recent research progress with phospholipase C from Bacillus cereus.

    Science.gov (United States)

    Lyu, Yan; Ye, Lidan; Xu, Jun; Yang, Xiaohong; Chen, Weiwei; Yu, Hongwei

    2016-01-01

    Phospholipase C (PLC) catalyzes the hydrolysis of phospholipids to produce phosphate monoesters and diacylglycerol. It has many applications in the enzymatic degumming of plant oils. PLC Bc , a bacterial PLC from Bacillus cereus, is an optimal choice for this activity in terms of its wide substrate spectrum, high activity, and approved safety. Unfortunately, its large-scale production and reliable high-throughput screening of PLC Bc remain challenging. Herein, we summarize the research progress regarding PLC Bc with emphasis on the screening methods, expression systems, catalytic mechanisms and inhibitor of PLC Bc . This review hopefully will inspire new achievements in related areas, to promote the sustainable development of PLC Bc and its application. PMID:26437973

  2. Biodegradation and corrosion behavior of manganese oxidizer Bacillus cereus ACE4 in diesel transporting pipeline

    International Nuclear Information System (INIS)

    The degradation problem of petroleum products arises since hydrocarbon acts as an excellent food source for a wide variety of microorganisms. Microbial activity leads to unacceptable level of turbidity, corrosion of pipeline and souring of stored product. The present study emphasizes the role of Bacillus cereus ACE4 on degradation of diesel and its influence on corrosion of API 5LX steel. A demonstrating bacterial strain ACE4 was isolated from corrosion products and 16S rRNA gene sequence analysis showed that it has more than 99% similarity with B. cereus. The biodegradation and corrosion studies revealed that B. cereus degraded the aliphatic protons and aromatic protons in diesel and is capable of oxidizing ferrous/manganese into oxides. This is the first report that discloses the involvement of manganese oxidizer B. cereus ACE4 on biodegradation of diesel and its influence on corrosion in a tropical country pipeline

  3. Presence of Bacillus cereus in Packaged Some Spices and Herbs Sold in Istanbul

    Directory of Open Access Journals (Sweden)

    Harun Aksu

    2000-01-01

    Full Text Available Ninety-three samples of packaged spices and herbs were collected from different retail shops in Istanbul, Turkey. They were examined for the presence and number of Bacillus cereus. It was determined that fifty-nine samples (63.44% contained more 100 cfu/g of B.cereus, with counts ranging from 102 to 3.2x103 cfu/g. In the 34 samples (36.56%, B.cereus were less 102 cfu/g. Only 5 samples (5.38% had counts between 103-104 cfu/g. The results suggest that incidence of B.cereus was very high in spices and herbs, and therefore should not be ignored in food industry, especially in the meat industry and mass catering establishments.

  4. Occurrence and significance of Bacillus cereus and Bacillus thuringiensis in ready-to-eat food

    DEFF Research Database (Denmark)

    Rosenquist, Hanne; Ørum-Smidt, Lasse; Andersen, Sigrid R;

    2005-01-01

    had at least one gene or component involved in human diarrhoeal disease, while emetic toxin was related to only one B. cereus strain. A new observation was that 31 out of the 40 randomly selected B. cereus-like strains could be classified as Bacillus thuringiensis due to crystal production and......Among 48,901 samples of ready-to-eat food products at the Danish retail market, 0.5% had counts of Bacillus cereus-like bacteria above 10(4) cfu g(-1). The high counts were most frequently found in starchy, cooked products, but also in fresh cucumbers and tomatoes. Forty randomly selected strains....../or content of cry genes. Thus, a large proportion of the B. cereus-like organisms present in food may belong to B. thuringiensis....

  5. Relapsing peritonitis with Bacillus cereus in a patient on continuous ambulatory peritoneal dialysis.

    Science.gov (United States)

    Magnussen, Eyð Tausen; Vang, Amanda Gratton; Á Steig, Torkil; Gaini, Shahin

    2016-01-01

    We present a case where Bacillus cereus was determined to be the causative agent of relapsing peritonitis in a patient on continuous ambulatory peritoneal dialysis (CAPD). The patient, a 70-year-old man from the Faroe Islands, was admitted with relapsing peritonitis four times over a 3-month period. Peritoneal cultures were positive for growth of B. cereus, a rare bacterial cause of peritonitis. The cultures demonstrated susceptibility to vancomycin, and therefore the patient was treated with intraperitoneal vancomycin, intraperitoneal gentamycin and oral ciprofloxacin. As a result of the relapsing B. cereus peritonitis diagnosis and a CT scan showing contraction of the peritoneum after longstanding inflammation, the peritoneal catheter was removed and the patient converted to haemodialysis. To date, the patient has not been readmitted due to peritonitis. A lack of proper hygiene when changing the dialysis bag was the suspected source of infection with B. cereus. PMID:27118739

  6. Detection and expression of enterotoxin genes in endophytic strains of Bacillus cereus

    OpenAIRE

    Melnick, Rachel L; Testen, Anna L.; Poleatewich, A.M.; Backman, Paul A.; Bailey, B. A.

    2012-01-01

    The aim of this study was to determine whether endophytic Bacillus cereus isolates from agronomic crops possessed genes for the nonhaemolytic enterotoxin (Nhe) and haemolysin BL (HBL) and, therefore, have the potential to cause diarrheal illness in humans.

  7. Meningitis due to Bacillus cereus: A case report and review of the literature.

    Science.gov (United States)

    Stevens, Michael P; Elam, Kara; Bearman, Gonzalo

    2012-01-01

    Bacillus cereus is infrequently associated with invasive central nervous system (CNS) disease. Infection is associated with conditions that lead to reduced host immunity and provide direct access to the CNS, such as spinal anesthesia and ventricular tubes and shunts. A case of ventriculitis secondary to B cereus in a patient receiving intrathecal chemotherapy is reported, along with a review of the current literature. B cereus can colonize medical devices, thus posing a risk for invasive disease. Despite aggressive treatment with broad-spectrum anti-infectives, the mortality of CNS invasive B cereus is high. Clinicians should not dismiss Gram-positive rods resembling Bacillus species from normally sterile sites as contaminants in critically ill patients. Appropriate antibiotic therapy should be promptly initiated to limit morbidity and mortality. PMID:23449377

  8. Whole-Genome Sequences of 94 Environmental Isolates of Bacillus cereus Sensu Lato

    OpenAIRE

    Van der Auwera, Géraldine A.; Feldgarden, Michael; Kolter, Roberto; Mahillon, Jacques

    2013-01-01

    Bacillus cereus sensu lato is a species complex that includes the anthrax pathogen Bacillus anthracis and other bacterial species of medical, industrial, and ecological importance. Their phenotypes of interest are typically linked to large plasmids that are closely related to the anthrax plasmids pXO1 and pXO2. Here, we present the draft genome sequences of 94 isolates of B. cereus sensu lato, which were chosen for their plasmid content and environmental origins.

  9. Whole-Genome Sequences of 94 Environmental Isolates of Bacillus cereus Sensu Lato

    OpenAIRE

    Van der Auwera, Géraldine A.; Feldgarden, Michael; Kolter, Roberto; Mahillon, Jacques

    2013-01-01

    Bacillus cereus sensu lato is a species complex that includes the anthrax pathogen Bacillus anthracis and other bacterial species of medical, industrial, and ecological importance. Their phenotypes of interest are typically linked to large plasmids that are closely related to the anthrax plasmids pXO1 and pXO2. Here, we present the draft genome sequences of 94 isolates of B. cereus sensu lato, which were chosen for their plasmid content and environmental origins.

  10. Zwittermicin A-producing strains of Bacillus cereus from diverse soils.

    OpenAIRE

    Stabb, E V; Jacobson, L. M.; Handelsman, J

    1994-01-01

    Bacillus cereus UW85 produces a novel aminopolyol antibiotic, zwittermicin A, that contributes to the ability of UW85 to suppress damping-off of alfalfa caused by Phytophthora medicaginis. UW85 produces a second antibiotic, provisionally designated antibiotic B, which also contributes to suppression of damping-off but has not been structurally defined yet and is less potent than zwittermicin A. The purpose of this study was to isolate genetically diverse strains of B. cereus that produce zwit...

  11. Evaluation of the Sporicidal Activity of Ethanol Extract of Arctium lappa Root against Bacillus cereus

    OpenAIRE

    Vajihe Karbasizade; Arezoo Dabiri

    2014-01-01

    Background: Bacillus cereus is one of the most common causes of food spoilage, keratitis, endophthalmitis, and panophthalmitis. These bacteria produce spores which are resistant to chemical and physical agents. Nowadays, the sporicidal properties of plants have been considered as alternatives to chemical sporicidal agents. Materials and Methods: In this empirical-experimental study the effect of ethanol extract of edible burdock (Arctium lappa) root has been studied on Bacillus cereus spo...

  12. Identification and analysis of the antigens detected by two commercial Bacillus cereus diarrheal enterotoxin immunoassay kits.

    OpenAIRE

    Beecher, D J; Wong, A C

    1994-01-01

    The usefulness of two commercial immunoassays for the detection of diarrheal enterotoxin of Bacillus cereus is unclear because the identity of the enterotoxin(s) has not been proven and the kits detect different proteins. We found that the Bacillus cereus Enterotoxin-Reversed Passive Latex Agglutination kit (Oxoid) detects the L2 component from hemolysin BL, and the Bacillus Diarrhoeal Enterotoxin Visual Immunoassay (Tecra) detects two apparently nontoxic proteins.

  13. Infective endocarditis due to Bacillus cereus in a pregnant female: A case report and literature review

    OpenAIRE

    Mahek Shah; Soumya Patnaik; Supakanya Wongrakpanich; Yaser Alhamshari; Talal Alnabelsi

    2015-01-01

    Incidence of infective endocarditis during pregnancy is around 0.006% with high maternal and fetal mortality. Bacillus cereus is an extremely rare cause for endocarditis in intravenous drug abusers (IVDA) or those with valvular disease or devices such as pacemakers. We report a case of B. cereus endocarditis, which, to the best of our knowledge, has never been reported in pregnancy. A 30-year-old, 25-week pregnant female presented with right shoulder pain, swelling and erythema on the lateral...

  14. Air-liquid interface biofilms of Bacillus cereus: formation, sporulation, and dispersion

    OpenAIRE

    Wijman, J.G.E.; Leeuw, van der, R.; Moezelaar, R.; Zwietering, M.H.; Abee, T.

    2007-01-01

    Biofilm formation by Bacillus cereus was assessed using 56 strains of B. cereus, including the two sequenced strains, ATCC 14579 and ATCC 10987. Biofilm production in microtiter plates was found to be strongly dependent on incubation time, temperature, and medium, as well as the strain used, with some strains showing biofilm formation within 24 h and subsequent dispersion within the next 24 h. A selection of strains was used for quantitative analysis of biofilm formation on stainless steel co...

  15. Differentiation between spores of Bacillus anthracis and Bacillus cereus by a quantitative immunofluorescence technique.

    OpenAIRE

    Phillips, A. P.; Martin, K L; Broster, M G

    1983-01-01

    A quantitative immunofluorescence assay based on fiber optic microscopy was used to measure the reaction of formalized spores of Bacillus anthracis and Bacillus cereus isolates with fluorescein conjugates prepared by hyperimmunization with B. anthracis Vollum spores. The spores of 11 of the 20 B. cereus strains reacted with the anti-anthrax conjugate to such an extent that they were indistinguishable from the spores of the several B. anthracis isolates tested. However, absorption of the conju...

  16. A Cluster of Bacillus cereus Bacteremia Cases among Injection Drug Users

    OpenAIRE

    Benusic, Michael A; Press, Natasha M; Linda MN Hoang; Romney, Marc G.

    2015-01-01

    Bacillus cereus is a ubiquitous spore-forming organism that is infrequently implicated in extraintestinal infections. The authors report three cases of B cereus bacteremia among injection drug users presenting within one month to an urban tertiary care hospital. Treatment with intravenous vancomycin was successful in all three cases. While temporal association suggested an outbreak, molecular studies of patient isolates using pulsed-field gel electrophoresis did not suggest a common source. A...

  17. PENGARUH EKSTRAK ANDALIMAN (Zanthoxyium acanthopodium DC TERHADAP PERMEABILITAS DAN HIDROFOBISITAS Bacillus cereus [Effect of Andaliman (Zanthoxylum acanthopodium DC Extracts upon Permeability and Hidrophobicity of Bacillus cereus

    Directory of Open Access Journals (Sweden)

    Sedarnawati Yasni2

    2005-04-01

    Full Text Available Andaliman spice is usually added as one of main spices in cooked fish and meat. Andaliman seeds were extracted using maceration method with nonpolar, semipolar and polar solvents. The result showed that the three kinds of andaliman extract had antibacterial activity on Bacillus cereus, especially during exponential phase (8 hour incubation period. Ethyl-acetate extract of Andaliman showed the highest antibacterial activity toward B. cereus with MIC and MBC values being 0.2% and 0.8% respectively. The permeability of B. cereus was observed at the dose of 2.5 MIC and 60.30% hydrophobicity leakage was obtained at 6% andaliman extracted by ethyl-acetate.

  18. Modeling of Bacillus cereus distribution in pasteurized milk at the time of consumption

    Directory of Open Access Journals (Sweden)

    Ľubomír Valík

    2013-02-01

    Full Text Available Normal 0 21 false false false SK X-NONE X-NONE Modelling of Bacillus cereus distribution, using data from pasteurized milk produced in Slovakia, at the time of consumption was performed in this study. The Modular Process Risk Model (MPRM methodology was applied to over all the consecutive steps in the food chain. The main factors involved in the risk of being exposed to unacceptable levels of B. cereus (model output were the initial density of B. cereus after milk pasteurization, storage temperatures and times (model input. Monte Carlo simulations were used for probability calculation of B. cereus density. By applying the sensitivity analysis influence of the input factors and their threshold values on the final count of B. cereus were determined. The results of the general case exposure assessment indicated that almost 14 % of Tetra Brik cartons can contain > 104 cfu/ml of B. cereus at the temperature distribution taken into account and time of pasteurized milk consumption. doi:10.5219/264

  19. Proteomic evidences for rex regulation of metabolism in toxin-producing Bacillus cereus ATCC 14579.

    Directory of Open Access Journals (Sweden)

    Sabrina Laouami

    Full Text Available The facultative anaerobe, Bacillus cereus, causes diarrheal diseases in humans. Its ability to deal with oxygen availability is recognized to be critical for pathogenesis. The B. cereus genome comprises a gene encoding a protein with high similarities to the redox regulator, Rex, which is a central regulator of anaerobic metabolism in Bacillus subtilis and other Gram-positive bacteria. Here, we showed that B. cereus rex is monocistronic and down-regulated in the absence of oxygen. The protein encoded by rex is an authentic Rex transcriptional factor since its DNA binding activity depends on the NADH/NAD+ ratio. Rex deletion compromised the ability of B. cereus to cope with external oxidative stress under anaerobiosis while increasing B. cereus resistance against such stress under aerobiosis. The deletion of rex affects anaerobic fermentative and aerobic respiratory metabolism of B. cereus by decreasing and increasing, respectively, the carbon flux through the NADH-recycling lactate pathway. We compared both the cellular proteome and exoproteome of the wild-type and Δrex cells using a high throughput shotgun label-free quantitation approach and identified proteins that are under control of Rex-mediated regulation. Proteomics data have been deposited to the ProteomeXchange with identifier PXD000886. The data suggest that Rex regulates both the cross-talk between metabolic pathways that produce NADH and NADPH and toxinogenesis, especially in oxic conditions.

  20. Properties of the Bacillus Cereus strain used in probiotic CenBiot Propriedades da cepa de Bacillus cereus utilizada no probiótico CenBiot

    OpenAIRE

    Carlos Gil-Turnes; Andrea Freitas dos Santos; Flávia Weykamp da Cruz; Alegani Vieira Monteiro

    1999-01-01

    Bacillus cereus CenBiot fulfilled the requirements to be used as probiotic. The spores showed D80 of 14 hs, inhibited Escherichia coli and Yersinia pseudotuberculosis after 24 hs in associative culture, were innocuous for suckling and adult mice and were not inhibited by antibiotics at low concentrations.Bacillus cereus CenBiot possui as características necessárias para ser utilizada como probiótico. Os esporos apresentaram D80 de 14 hs, inibiram Escherichia coli e Yersinia pseudotuberculosis...

  1. Bacillus cereus un patógeno importante en el control microbiológico de los alimentos / Bacillus cereus an important pathogen the microbiological control of food

    OpenAIRE

    Jennifer Sánchez; Margarita Correa; Laura M. Castañeda-Sandoval

    2016-01-01

    Resumen Bacillus cereus es una bacteria genéticamente diversa que se encuentra comúnmente en el ambiente. Contamina los alimentos afectando la salud humana, al ingerir el microorganismo y/o sus toxinas, la emética o las enterotoxinas. En Colombia son escasos los reportes de intoxicación por B. cereus y se estima que hay un gran subregistro. Por lo anterior, se recomienda aumentar la vigilancia de este patógeno y realizar estudios sobre aspectos relevantes que permitan aplicar medidas de co...

  2. Deletion of the sigB Gene in Bacillus cereus ATCC 14579 Leads to Hydrogen Peroxide Hyperresistance

    OpenAIRE

    Schaik, van, G.; Zwietering, M.H.; Vos, de, W.M.; Abee, T.

    2005-01-01

    The sigB gene of Bacillus cereus ATCC 14579 encodes the alternative sigma factor σB. Deletion of sigB in B. cereus leads to hyperresistance to hydrogen peroxide. The expression of katA, which encodes one of the catalases of B. cereus, is upregulated in the sigB deletion mutant, and this may contribute to the hydrogen peroxide-resistant phenotype.

  3. Evaluation of the representativeness of a Dutch non-malformed control group for the general pregnant population : are these controls useful for EUROCAT?

    NARCIS (Netherlands)

    Jentink, J.; Zetstra-van der Woude, A.P.; Bos, Jens; De Jong-Van den Berg, L.T.

    2011-01-01

    Purpose A case-control study is the most powerful design to test the risk of specific congenital malformations associated with a specific drug. However, malformation registries often lack non-malformed controls. For the Dutch EUROCAT, we collected a non-malformed control group: the 'Healthy Pregnant

  4. Custo adaptativo da indução de resistência em feijoeiro mediada pela rizobactéria Bacillus cereus ou acibenzolar-S-metil: atividade de enzimas, síntese de fenóis e lignina e biomassa Fitness cost of induced resistance in bean plants by the rhizobacteria Bacillus cereus or acibenzolar-S-methyl: enzymes activities, phenol and lignin synthesis, and biomass

    Directory of Open Access Journals (Sweden)

    Odair José Kuhn

    2010-06-01

    synthesis and plant growth were evaluated too. It was observed that the inducers protected the bean plants against X. axonopodis pv. phaseoli. The ASM increased the activity of peroxidase, chitinase and β-1,3-glucanase, while B. cereus only increased peroxidase activity. Unlike B. cereus, the ASM increased lignin synthesis and decreased phenolic compound content and plant growth. Therefore, the resistance induced by ASM represents high fitness costs for bean plants, while the resistance induced by B. cereus represents low cost and its potential use can be explored.

  5. Post-traumatic stress symptoms and childhood abuse categories in a national representative sample for a specific age group: associations to body mass index

    OpenAIRE

    Roenholdt, Stine; Nina N. Beck; Sidsel H. Karsberg; Elklit, Ask

    2012-01-01

    Background: Studies of specific groups such as military veterans have found that posttraumatic stress disorder (PTSD) is linked to adverse health outcomes including unhealthy weight. The aim of this study was to examine the relationship between PTSD symptoms, experiences of childhood trauma and weight in a community sample. Methods: A stratified random probability survey was conducted in Denmark by the Danish National Centre for Social Research between 2008 and 2009 with 2,981 participants bo...

  6. Widening access to UK medical education for under-represented socioeconomic groups: modelling the impact of the UKCAT in the 2009 cohort

    OpenAIRE

    Tiffin, P. A.; Dowell, J. S.; McLachlan, J.C.

    2012-01-01

    Objective: To determine whether the use of the UK clinical aptitude test (UKCAT) in the medical schools admissions process reduces the relative disadvantage encountered by certain sociodemographic groups. Design: Prospective cohort study. Setting: Applicants to 22 UK medical schools in 2009 that were members of the consortium of institutions utilising the UKCAT as a component of their admissions process. Participants: 8459 applicants (24 844 applications) to UKCAT consortium membe...

  7. Statement delivered in the Board of Governors on 28 November 2008 by the Resident Representative of Zimbabwe on behalf of the group of members of the African Union concerning the appointment of the Director General

    International Nuclear Information System (INIS)

    On 28 November 2008, the Resident Representative of Zimbabwe to the Agency delivered a statement in the Board of Governors, on behalf of the group of members of the African Union, concerning the appointment of the Director General. As requested in the statement, the statement is herewith circulated for the information of Member States

  8. Isolation and characterization of an acrylamide-degrading Bacillus cereus.

    Science.gov (United States)

    Shukor, M Y; Gusmanizar, N; Azmi, N A; Hamid, M; Ramli, J; Shamaan, N A; Syed, M A

    2009-01-01

    Several local acrylamide-degrading bacteria have been isolated. One of the isolate that exhibited the highest growth on acrylamide as a nitrogen source was then further characterized. The isolate was tentatively identified as Bacillus cereus strain DRY135 based on carbon utilization profiles using Biolog GP plates and partial 16S rDNA molecular phylogeny. The isolate grew optimally in between the temperatures of 25 and 30 degrees C and within the pH range of 6.8 to 7.0. Glucose, fructose, lactose, maltose, mannitol, citric acid and sucrose supported growth with glucose being the best carbon source. Different concentrations of acrylamide ranging from 100 to 4000 mg l(-1) incorporated into the growth media shows that the highest growth was obtained at acrylamide concentrations of between 500 to 1500 mg l(-1). At 1000 mg l(-1) of acrylamide, degradation was 90% completed after ten days of incubation with concomitant cell growth. The metabolite acrylic acid was detected in the media during degradation. Other amides such as methacrylamide, nicotinamide, acetamide, propionamide and urea supported growth with the highest growth supported by acetamide, propionamide and urea. Strain DRY135, however was not able to assimilate 2-chloroacetamide. The characteristics of this isolate suggest that it would be useful in the bioremediation of acrylamide. PMID:20112864

  9. Investigation of the Bacillus cereus phosphonoacetaldehyde hydrolase catalytic mechanism

    International Nuclear Information System (INIS)

    The enzyme phosphonoacetaldehyde hydrolase (phosphonatase) from Bacillus cereus catalyzes the conversion of phosphonoacetaldehyde and phosphate. We have demonstrated that phosphonatase is inactivated when incubated with either acetaldehyde or phosphonoacetaldehyde for short time periods at low temperature in the presence of NaBH4. This result suggests that the Schiff base mechanism is operative since such treatment might be expected to inactivate the enzyme by reducing an iminium cation mechanistic intermediate. The inactivation process was shown to be highly specific for a single lysine residue. Incubation of phosphonatase with [3H]-NaBH4 and phosphonacetaldehyde [14C]-acetaldehyde and NaBH4 or [C2-3H]- phosphonoacetaldehyde and NaBH4 resulted in radiolabeled inactivated enzyme. Tryptic hydrolysis and reverse phase HPLC chromatography of the resulting digests demonstrated that the [C2 - 3H]- phosphonoacetaldehyde/NaBH4 methodology afforded the most specifically tritium labeled, inactivated phosphonatase. The radiolabeled, active site peptide was purified to homogeneity and its amino acid sequence was determined

  10. Vacuum Distillation Residue Upgrading by an Indigenous Bacillus Cereus

    Directory of Open Access Journals (Sweden)

    Mitra Sadat Tabatabaee

    2013-07-01

    Full Text Available Background:Biological processing of heavy fractions of crude oils offers less severe process conditions and higher selectivity for refining. Biochemical Processes are expected to be low demand energy processes and certainly ecofriendly.Results:A strain of biosurfactant producing bacterium was isolated from an oil contaminated soil at Tehran refinery distillation unit. Based on selected phenotypic and genotypic characteristic including morphology, biochemical proprety, and 16 SrRNA sequencing identified as a novel strain of Bacillus cereus (JQ178332. This bacterium endures a wide range of pH, salinity and temperature. This specific strain utilizes both paraffin and anthracene as samples of aliphatic and polycyclic aromatic hydrocarbons. The ability of this bacterium to acquire all its energy and chemical requirements from Vacuum Distillation Residue (VR, as a net sample of problematic hydrocarbons in refineries, was studied. SARA test ASTM D4124-01 revealed 65.5% decrease in asphaltenic, 22.1% in aliphatics and 30.3% in Aromatics content of the VR in MSM medium. Further results with 0.9% saline showed 55% decrease in asphaltene content and 2.1% Aromatics respectively.Conclusion:Remarkable abilities of this microorganism propose its application in an ecofriendly technology to upgrade heavy crude oils.

  11. Post-traumatic stress symptoms and childhood abuse categories in a national representative sample for a specific age group: associations to body mass index

    Directory of Open Access Journals (Sweden)

    Sidsel H. Karsberg

    2012-06-01

    Full Text Available Background: Studies of specific groups such as military veterans have found that posttraumatic stress disorder (PTSD is linked to adverse health outcomes including unhealthy weight. The aim of this study was to examine the relationship between PTSD symptoms, experiences of childhood trauma and weight in a community sample. Methods: A stratified random probability survey was conducted in Denmark by the Danish National Centre for Social Research between 2008 and 2009 with 2,981 participants born in 1984, achieving a response rate of 67%. The participants were interviewed with a structured interview with questions pertaining PTSD symptomatology, exposure to childhood abuse, exposure to potentially traumatizing events, height, and weight. Underweight was defined by a body mass index (BMI <18.5, overweight was defined by a BMI ≥25 and <30 and obesity was defined by a BMI ≥30. Results: PTSD symptomatology and childhood abuse were significantly associated with both underweight and overweight/obesity. Childhood emotional abuse was especially associated with underweight, whereas sexual abuse and overall abuse were particularly associated with overweight/obesity. Conclusion: These findings indicate that health care professionals may benefit from assessing PTSD and childhood abuse in the treatment of both overweight and underweight individuals.

  12. Architecture and High-Resolution Structure of Bacillus thuringiensis and Bacillus cereus Spore Coat Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Plomp, M; Leighton, T; Wheeler, K; Malkin, A

    2005-02-18

    We have utilized atomic force microscopy (AFM) to visualize the native surface topology and ultrastructure of Bacillus thuringiensis and Bacillus cereus spores in water and in air. AFM was able to resolve the nanostructure of the exosporium and three distinctive classes of appendages. Removal of the exosporium exposed either a hexagonal honeycomb layer (B. thuringiensis) or a rodlet outer spore coat layer (B. cereus). Removal of the rodlet structure from B. cereus spores revealed an underlying honeycomb layer similar to that observed with B. thuringiensis spores. The periodicity of the rodlet structure on the outer spore coat of B. cereus was {approx}8 nm, and the length of the rodlets was limited to the cross-patched domain structure of this layer to {approx}200 nm. The lattice constant of the honeycomb structures was {approx}9 nm for both B. cereus and B. thuringiensis spores. Both honeycomb structures were composed of multiple, disoriented domains with distinct boundaries. Our results demonstrate that variations in storage and preparation procedures result in architectural changes in individual spore surfaces, which establish AFM as a useful tool for evaluation of preparation and processing ''fingerprints'' of bacterial spores. These results establish that high-resolution AFM has the capacity to reveal species-specific assembly and nanometer scale structure of spore surfaces. These species-specific spore surface structural variations are correlated with sequence divergences in a spore core structural protein SspE.

  13. Shelf Life Extension of Cheddar Processed Cheese Using Polyethylene Coating Films of Nisin against Bacillus cereus

    Directory of Open Access Journals (Sweden)

    Nizar Issa Alrabadi

    2012-01-01

    Full Text Available Antimicrobial food packaging is vital issue. This study aimed to test shelf life extension of Cheddar Processed Cheese at room temperature using low-density polyethylene (LDPE films incorporating nisin against Bacillus cereus. In particular, the efficiency of different treatments was tested against Bacillus cereus. Different concentrations (0, 500, 1000, 2000, 4000, 8000, 16000 IU mL-1 of nisin were used in activating (coating LDPE films. There was no mainly clear difference in inhibition zone from 2000 to 16000 IU, so that a concentration of 2000 IU was used for active packaging. Four different treatments were tested in cheese: samples without coating; samples without coating and inculcated by Bacillus cereus; samples coating by polyethylene films that activated by nisin without inoculation and samples coating by the same films and inoculated by Bacillus cereus. Microbiological analyses including total count, spore forming bacteria and yeast and moulds of the cheese samples were performed during 8 months. Results indicated that the cheese which coated with polyethylene films that treated with nisin regardless whether it was inculcated or not were free of Bacillus cereus bacteria.

  14. Gamma radiation effect on Bacillus cereus spores inoculated in black pepper

    International Nuclear Information System (INIS)

    It had been analyzed 37 samples of worn out black pepper and in 85% of these samples was observed the presence of Bacillus cereus in numbers of up to 4,6 x 104 UFC/g. The population of aerobic mesofilis bacteria varied of 2,8 x 105 the 1,9 x 108 UFC/g. The black pepper used during the experiment was evaluated, evidencing the aerobic presence of one aerobic mesofilis microbiota of, approximately, 2,6 x 106 UFC/g, consisting, mainly, for species of the Bacillus sort. It was observed that the absence of B. cereus, coliforms, filamentous fungus and leavenings. The evaluation of the irradiation of the black pepper inoculated with 106 UFC/g of B. cereus spores of with doses of gamma radiation varying between 2 and 10 kGy evidenced that doses up to 5 kGy had been enough to reduce the counting of, approximately, 106 UFC/g of aerobic mesofilis organisms and 104 UFC/g of B. cereus spores the not detectable numbers by the used methodology. The dose of reduction decimal (D10) for the inoculated B. cereus spores in black pepper was of 1,78 kGy

  15. Detection of toxin genes and RAPD analysis of bacillus cereus isolates from different soil types

    Directory of Open Access Journals (Sweden)

    Savic Dejana

    2015-01-01

    Full Text Available The aim of this study was to detect genes for enterotoxins (hbla, entFM and bceT and for emetic toxin (cer, to determine antibiotic resistance, and to estimate intraspecies diversity in B. cereus isolates by RAPD analysis. B. cereus was identified in 12 out of 117 indigenous Bacillus spp. using the classical microbiological methods and PCR. All isolates were resistant to penicillin and ampicillin, two to tetracyclin and four to trimethoprim-sulphamethoxazole. Also, all isolates produced inducible penicillinases and β-lactamase. Toxin genes were detected with PCR. EntFM and cer genes were present in all isolates, hbla in all, but two, and bceT in none. RAPD analysis was performed with four different primers, two of them designed for this study. The intraspecies diversity revealed 10 different patterns at the 90% similarity level. Two separate clusters were formed regardless of a soil type or utilization. The detection of genes encoding toxins in all B. cereus isolates indicated these bacteria as potentially pathogenic and seriously for human health. Regardless of a soil type or utilization, the RAPD analysis showed high intraspecies heterogeneity in B. cereus isolates. To the best of our knowledge, this is the first study to analyse the presence of entero- and emetic toxin genes and genetic heterogeneity in B. cereus isolates from different soil types and different soil utilization in Serbia. [Projekat Ministarstva nauke Republike Srbije, br. TR37006

  16. Simultaneous removal of chlorothalonil and nitrate by Bacillus cereus strain NS1

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Yiqiang [Department of Environmental Sciences, University of California, Riverside, Riverside, CA-92521 (United States)]. E-mail: yqzhang@ucr.edu; Lu Jianhang [Department of Environmental Sciences, University of California, Riverside, Riverside, CA-92521 (United States); Wu Laosheng [Department of Environmental Sciences, University of California, Riverside, Riverside, CA-92521 (United States); Chang, Andrew [Department of Environmental Sciences, University of California, Riverside, Riverside, CA-92521 (United States); Frankenberger, William T. [Department of Environmental Sciences, University of California, Riverside, Riverside, CA-92521 (United States)

    2007-09-01

    Elevated NO{sub 3} {sup -} and chlorothalonil (CTN) have been found in production nursery recycling ponds. Bacillus cereus strain NS1 isolated from nursery recycling pond sediment was assessed for its ability to reduce NO{sub 3} {sup -} and degrade CTN in a mineral medium. The results showed that the efficiency of NO{sub 3} {sup -} reduction and CTN degradation by B. cereus strain NS1 were related to the nature of organic carbon sources added to the medium. In the medium amended with 100 mg/L yeast extract, 86% of NO{sub 3} {sup -} (100 mg/L) and 99% of CTN (78 {mu}g/L) were simultaneously removed by B. cereus strain NS1 during the first day of the experiment. It took 6 days for the removal of 82-93% of NO{sub 3} {sup -} and 87-91% of CTN in the media containing glucose and acetate. B. cereus strain NS1 needed organic carbon as energy sources and electron donors to respire NO{sub 3} {sup -}, and simultaneously degrade CTN. These results suggest that B. cereus strain NS1 may have great potential to remediate NO{sub 3} {sup -} and CTN contaminated water in nursery recycling ponds.

  17. Bacillus cereus Response to a Proanthocyanidin Trimer, a Transcriptional and Functional Analysis.

    Science.gov (United States)

    Tamura, Tomoko; Ozawa, Megumi; Tanaka, Naoto; Arai, Soichi; Mura, Kiyoshi

    2016-07-01

    Proanthocyanidins are abundant in peanut skin, and in this study, the antibacterial effects of a peanut skin extract (PSE) against food-borne bacteria were investigated to find its minimum inhibitory concentration. Food-borne gram-positive bacteria, and in particular Bacillus cereus, was more sensitive to PSE. In particular, the inhibitory activity of epicatechin-(4β → 6)-epicatechin-(2β → O→7, 4β → 8)-catechin (EEC), a proanthocyanidin trimer from peanut skin, against B. cereus was stronger than that of procyanidin A1, a proanthocyanidin dimer. DNA microarray analysis of B. cereus treated with EEC was carried out, with a finding that 597 genes were significantly up-regulated. Analysis of the up-regulated genes suggested that EEC disrupted the normal condition of the cell membrane and wall of B. cereus and alter its usual nutritional metabolism. Moreover, treatment of B. cereus with EEC inhibited glucose uptake, suggesting that EEC affects the cell-surface adsorption. PMID:27061585

  18. Simultaneous removal of chlorothalonil and nitrate by Bacillus cereus strain NS1

    International Nuclear Information System (INIS)

    Elevated NO3- and chlorothalonil (CTN) have been found in production nursery recycling ponds. Bacillus cereus strain NS1 isolated from nursery recycling pond sediment was assessed for its ability to reduce NO3- and degrade CTN in a mineral medium. The results showed that the efficiency of NO3- reduction and CTN degradation by B. cereus strain NS1 were related to the nature of organic carbon sources added to the medium. In the medium amended with 100 mg/L yeast extract, 86% of NO3- (100 mg/L) and 99% of CTN (78 μg/L) were simultaneously removed by B. cereus strain NS1 during the first day of the experiment. It took 6 days for the removal of 82-93% of NO3- and 87-91% of CTN in the media containing glucose and acetate. B. cereus strain NS1 needed organic carbon as energy sources and electron donors to respire NO3-, and simultaneously degrade CTN. These results suggest that B. cereus strain NS1 may have great potential to remediate NO3- and CTN contaminated water in nursery recycling ponds

  19. Development of a double-antibody sandwich ELISA for rapid detection of Bacillus Cereus in food.

    Science.gov (United States)

    Zhu, Longjiao; He, Jing; Cao, Xiaohan; Huang, Kunlun; Luo, Yunbo; Xu, Wentao

    2016-01-01

    Bacillus cereus is increasingly recognized as one of the major causes of food poisoning in the industrialized world. In this paper, we describe a sensitive double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) that was developed for rapid detection of B. cereus in food to minimize the risk of contamination. The polyclonal antibody (pAb) and monoclonal antibodies (mAbs) specific to B. cereus were generated from rabbit antiserum and mouse ascites, respectively, using the octanoic acid/saturated ammonium sulfate precipitation method and protein A-sepharose columns. IgG-isotype mAbs were specially developed to undergo a novel peripheral multiple sites immunization for rapid gain of hybridomas and a subtractive screen was used to eliminate cross reactivity with closely related species such as Bacillus thuringiensis, B. subtilis, B. licheniformis and B. perfringens. The linear detection range of the method was approximately 1 × 10(4)-2.8 × 10(6) cells/mL with a detection limit (LOD) of 0.9 × 10(3) cells/mL. The assay was able to detect B. cereus when the samples were prepared in meat with various pathogens. The newly developed analytical method provides a rapid method to sensitively detect B. cereus in food specimens. PMID:26976753

  20. Infective endocarditis due to Bacillus cereus in a pregnant female: A case report and literature review.

    Science.gov (United States)

    Shah, Mahek; Patnaik, Soumya; Wongrakpanich, Supakanya; Alhamshari, Yaser; Alnabelsi, Talal

    2015-01-01

    Incidence of infective endocarditis during pregnancy is around 0.006% with high maternal and fetal mortality. Bacillus cereus is an extremely rare cause for endocarditis in intravenous drug abusers (IVDA) or those with valvular disease or devices such as pacemakers. We report a case of B. cereus endocarditis, which, to the best of our knowledge, has never been reported in pregnancy. A 30-year-old, 25-week pregnant female presented with right shoulder pain, swelling and erythema on the lateral aspect of deltoid muscle from large abscess over her deltoid muscle. She was found to have a vegetation on the native tricuspid valve. Cultures from abscess fluid and blood cultures grew B. cereus, she was appropriately treated with antimicrobials and had favorable outcomes. There are cereus endocarditis reported but none during pregnancy. When cultures grow unusual organisms the case must be thoroughly investigated. This case illustrates a rare situation (endocarditis in pregnancy) with an unusual outcome (B. cereus) on an uncommon valve (tricuspid valve). PMID:26793477

  1. Infective endocarditis due to Bacillus cereus in a pregnant female: A case report and literature review

    Directory of Open Access Journals (Sweden)

    Mahek Shah

    2015-01-01

    Full Text Available Incidence of infective endocarditis during pregnancy is around 0.006% with high maternal and fetal mortality. Bacillus cereus is an extremely rare cause for endocarditis in intravenous drug abusers (IVDA or those with valvular disease or devices such as pacemakers. We report a case of B. cereus endocarditis, which, to the best of our knowledge, has never been reported in pregnancy. A 30-year-old, 25-week pregnant female presented with right shoulder pain, swelling and erythema on the lateral aspect of deltoid muscle from large abscess over her deltoid muscle. She was found to have a vegetation on the native tricuspid valve. Cultures from abscess fluid and blood cultures grew B. cereus, she was appropriately treated with antimicrobials and had favorable outcomes. There are <20 cases of B. cereus endocarditis reported but none during pregnancy. When cultures grow unusual organisms the case must be thoroughly investigated. This case illustrates a rare situation (endocarditis in pregnancy with an unusual outcome (B. cereus on an uncommon valve (tricuspid valve.

  2. Quantification of the Effects of Salt Stress and Physiological State on Thermotolerance of Bacillus cereus ATCC 10987 and ATCC 14579

    NARCIS (Netherlands)

    Besten, den H.M.W.; Mataragas, M.; Moezelaar, R.; Abee, T.; Zwietering, M.H.

    2006-01-01

    The food-borne pathogen Bacillus cereus can acquire enhanced thermal resistance through multiple mechanisms. Two Bacillus cereus strains, ATCC 10987 and ATCC 14579, were used to quantify the effects of salt stress and physiological state on thermotolerance. Cultures were exposed to increasing concen

  3. Draft Genome Sequence of Bacillus cereus Strain BcFL2013, a Clinical Isolate Similar to G9241

    OpenAIRE

    Gee, Jay E.; Marston, Chung K.; Sammons, Scott A.; Burroughs, Mark A.; Hoffmaster, Alex R.

    2014-01-01

    Bacillus cereus strains, such as G9241, causing anthrax-like illnesses have recently been discovered. We report the genome sequence of a clinical strain, B. cereus BcFL2013, which is similar to G9241, recovered from a patient in Florida.

  4. 40 CFR 180.1181 - Bacillus cereus strain BPO1; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus cereus strain BPO1; exemption... FOOD Exemptions From Tolerances § 180.1181 Bacillus cereus strain BPO1; exemption from the requirement of a tolerance. An exemption from the requirement of a tolerance for residues of the Bacillus...

  5. Prevalence of Bacillus cereus in milk and rice grains collected from great Cairo

    International Nuclear Information System (INIS)

    Sixty two Samples of heat treated milk, raw rice grains and Cheetos (XO-Snacks) were collected from supermarkets of great Cairo. Seventeen out of 25 milk samples (68%) gave detectable count of B. cereus on MYP medium. These positive samples count was ranging from 1.5 X 101 cfu/ml to 11.3X102 cfu/ml. Eighteen out of 25 Samples of raw rice grains (72%) gave also detectable count on MYP medium also. The count of positive rice grains was ranging from 2.0X101 cfu/g to 11.5X103 cfu /ml. However one Sample out of 12 Samples (8%) of Cheetos (Snacks) was positive with count 3.0X102 cfu /g. Gamma irradiation reduced the total bacterial count and B. cereus count gradually. Eight kGy reduced total bacterial count and Bacillus cereus count by 3.1 and 2.2 log cycles respectively.

  6. BACILLUS CEREUS EM PRODUTOS LÁCTEOS - UMA REVISÃO

    OpenAIRE

    Maike Taís Maziero; Luciano dos Santos Bersot

    2011-01-01

    Bacillus cereus é uma bactéria termodúrica, formadora de esporos, capaz de se multiplicar em temperatura de refrigeração. Pode causar dois tipos de doenças de origem alimentar: a síndrome emética e a síndrome diarréica. Além do aspecto epidemiológico, B. cereus causa defeitos tecnológicos em produtos lácteos, relacionados com a produção de lipases e proteases. A presença de B. cereus em produtos lácteos vem sendo relatada por pesquisas feitas em vários países, bem como os defeitos tecnológico...

  7. Bacillus cereus maisto produktuose ir jų nustatymo metodai (apžvalga)

    OpenAIRE

    Šalomskienė, J.; Bartiuk, T.

    2006-01-01

    Straipsnyje pateiktas Bacillus cereus rūšies bakterijų apibūdinimas, jų paplitimo vietos, patekimo į maisto produktus būdai. Nurodytas maisto produktų užterštumas B. cereus (106/g), kuriam esant gali atsirasti produkto ydos (kartus ir apkartęs skonis, nešvarus, vaisių ir mielių kvapas ir kt.) ir susidaryti toksinų. B. cereus gali sukelti dviejų tipų žarnyno sutrikimus – diarėjinį ir emetinį apsinuodijimą. Terminis apdorojimas produktų gamybos metu sunaikina vegetatyvines ląsteles, tačiau tik ...

  8. Formation of cereulide and enterotoxins by Bacillus cereus in fermented African locust beans

    DEFF Research Database (Denmark)

    Thorsen, Line; Azokpota, Paulin; Munk Hansen, Bjarne; Rønsbo, Mie Hvillum; Nielsen, Kristian Fog; Hounhouigan, D. Joseph; Jakobsen, Mogens

    2011-01-01

    Afitin, iru and sonru are three spontaneously fermented African locust bean Benin condiments. The fermentation processes are exothermic, with temperatures mostly being above 40 °C. A total of 19 predominant Bacillus cereus isolates from afitin, iru and sonru, were investigated. The enterotoxin...... inoculated with emetic (cereulide producing) B. cereus Ba18H2/RIF supported growth at 25, 30 and 40 °C with highly different maximum cereulide productions of 6 ± 5, 97 ± 3 and 0.04 ± 0.02 μg/g beans, respectively (48 h). For non-autoclaved cooked beans inoculated with 2, 4 and 6 log10 B. cereus Ba18H2/RIF...

  9. Purification, crystallization and preliminary X-ray analysis of the peptidoglycan N-acetylglucosamine deacetylase BC1960 from Bacillus cereus in the presence of its substrate (GlcNAc)6

    International Nuclear Information System (INIS)

    The peptidoglycan N-acetylglucosamine (GlcNAc) deacetylase BC1960 from B. cereus was crystallized in the presence of the substrate (GlcNAc)6. The crystals belonged to space group P41212 and diffracted to 2.38 Å resolution. The peptidoglycan N-acetylglucosamine (GlcNAc) deacetylase BC1960 from Bacillus cereus (EC 3.5.1.33), an enzyme consisting of 275 amino acids, was crystallized in the presence of its substrate (GlcNAc)6. The crystals belonged to the tetragonal space group P41212, with unit-cell parameters a = b = 92.7, c = 242.9 Å and four molecules in the asymmetric unit. A complete data set was collected at 100 K to a resolution of 2.38 Å using synchrotron radiation

  10. A genomic region involved in the formation of adhesin fibers in Bacillus cereus biofilms

    Directory of Open Access Journals (Sweden)

    Joaquín eCaro-Astorga

    2015-01-01

    Full Text Available Bacillus cereus is a bacterial pathogen that is responsible for many recurrent disease outbreaks due to food contamination. Spores and biofilms are considered the most important reservoirs of B. cereus in contaminated fresh vegetables and fruits. Biofilms are bacterial communities that are difficult to eradicate from biotic and abiotic surfaces because of their stable and extremely strong extracellular matrix. These extracellular matrixes contain exopolysaccharides, proteins, extracellular DNA, and other minor components. Although B. cereus can form biofilms, the bacterial features governing assembly of the protective extracellular matrix are not known. Using the well-studied bacterium B. subtilis as a model, we identified two genomic loci in B. cereus, which encodes two orthologs of the amyloid-like protein TasA of B. subtilis and a SipW signal peptidase. Deletion of this genomic region in B. cereus inhibited biofilm assembly; notably, mutation of the putative signal peptidase SipW caused the same phenotype. However, mutations in tasA or calY did not completely prevent biofilm formation; strains that were mutated for either of these genes formed phenotypically different surface attached biofilms. Electron microscopy studies revealed that TasA polymerizes to form long and abundant fibers on cell surfaces, whereas CalY does not aggregate similarly. Heterologous expression of this amyloid-like cassette in a B. subtilis strain lacking the factors required for the assembly of TasA amyloid-like fibers revealed i the involvement of this B. cereus genomic region in formation of the air-liquid interphase pellicles and ii the intrinsic ability of TasA to form fibers similar to the amyloid-like fibers produced by its B. subtilis ortholog.

  11. Successful Treatment of Bacillus cereus Bacteremia in a Patient with Propionic Acidemia.

    Science.gov (United States)

    Aygun, Fatma Deniz; Aygun, Fatih; Cam, Halit

    2016-01-01

    Bacillus cereus can cause serious, life-threatening, systemic infections in immunocompromised patients. The ability of microorganism to form biofilm on biomedical devices can be responsible for catheter-related bloodstream infections. Other manifestations of severe disease are meningitis, endocarditis, osteomyelitis, and surgical and traumatic wound infections. The most common feature in true bacteremia caused by Bacillus is the presence of an intravascular catheter. Herein, we report a case of catheter-related bacteremia caused by B. cereus in a patient with propionic acidemia. PMID:27195164

  12. Successful Treatment of Bacillus cereus Bacteremia in a Patient with Propionic Acidemia

    Directory of Open Access Journals (Sweden)

    Fatma Deniz Aygun

    2016-01-01

    Full Text Available Bacillus cereus can cause serious, life-threatening, systemic infections in immunocompromised patients. The ability of microorganism to form biofilm on biomedical devices can be responsible for catheter-related bloodstream infections. Other manifestations of severe disease are meningitis, endocarditis, osteomyelitis, and surgical and traumatic wound infections. The most common feature in true bacteremia caused by Bacillus is the presence of an intravascular catheter. Herein, we report a case of catheter-related bacteremia caused by B. cereus in a patient with propionic acidemia.

  13. Successful Treatment of Bacillus cereus Bacteremia in a Patient with Propionic Acidemia

    Science.gov (United States)

    Aygun, Fatih; Cam, Halit

    2016-01-01

    Bacillus cereus can cause serious, life-threatening, systemic infections in immunocompromised patients. The ability of microorganism to form biofilm on biomedical devices can be responsible for catheter-related bloodstream infections. Other manifestations of severe disease are meningitis, endocarditis, osteomyelitis, and surgical and traumatic wound infections. The most common feature in true bacteremia caused by Bacillus is the presence of an intravascular catheter. Herein, we report a case of catheter-related bacteremia caused by B. cereus in a patient with propionic acidemia. PMID:27195164

  14. Two capsular polysaccharides enable Bacillus cereus G9241 to cause anthrax-like disease

    OpenAIRE

    Oh, So-Young; Budzik, Jonathan M.; Garufi, Gabriella; Schneewind, Olaf

    2011-01-01

    Bacillus cereus G9241 causes an anthrax-like respiratory illness in humans, however the molecular mechanisms of disease pathogenesis are not known. Genome sequencing identified two putative virulence plasmids proposed to provide for anthrax toxin (pBCXO1) and/or capsule expression (pBC218). We report here that B. cereus G9241 causes anthrax-like disease in immune-competent mice, which is dependent on each of the two virulence plasmids. pBCXO1 encodes pagA1, the homolog of anthrax protective a...

  15. Resistance and biosorption mechanism of silver ions by Bacillus cereus biomass

    Institute of Scientific and Technical Information of China (English)

    Li Li; Qing Hu; Jinghai Zeng; Hongyan Qi; Guoqiang Zhuang

    2011-01-01

    Biosorption of silver ions onto Bacillus cereus biomass was investigated.Overall kinetic experiments were performed for the determination of the necessary contact time for the attainment of equilibrium.It was found that the overall biosorption process was best described by pseudo second-order kinetic model.The crystals detected by scanning electron microscope and X-ray photoelectron spectroscopy suggested the precipitation was a possible mechanism of biosorption.The molecular genetics of silver resistance of B.cereus biomass was also detected and illustrated by a whole cell sensor tool.

  16. Regulation of toxin production by Bacillus cereus and its food safety implications.

    Science.gov (United States)

    Ceuppens, Siele; Rajkovic, Andreja; Heyndrickx, Marc; Tsilia, Varvara; Van De Wiele, Tom; Boon, Nico; Uyttendaele, Mieke

    2011-08-01

    Toxin expression is of utmost importance for the food-borne pathogen B. cereus, both in food poisoning and non-gastrointestinal host infections as well as in interbacterial competition. Therefore it is no surprise that the toxin gene expression is tightly regulated by various internal and environmental signals. An overview of the current knowledge regarding emetic and diarrheal toxin transcription and expression is presented in this review. The food safety aspects and management tools such as temperature control, food preservatives and modified atmosphere packaging are discussed specifically for B. cereus emetic and diarrheal toxin production. PMID:21417966

  17. Mechanism and site of inhibition of Bacillus cereus spore outgrowth by nitrosothiols

    International Nuclear Information System (INIS)

    Structure vs. activity studies demonstrate that nitrosothiols inhibit outgrowth of B. cereus spores by reversible covalent bond formation with sensitive spore components. Kinetic studies of the binding of nitrosothiols and iodoacetate, a known sulfhydryl reagent, show that they complete for the same spore sites. Since two other nitrite derivatives, the Perigo factor and the transferrin inhibitor, interfere with iodoacetate label uptake in a kinetically similar fashion, all of these compounds may inhibit spore outgrowth by interacting with the same spore thiol groups. Disruption of spores which have been inhibited by radioactive iodoacetate demonstrates that much of the label is incorporated into a membrane-rich fraction that sediments as a single peak on a sucrose density gradient. SDS gel electrophoresis and autofluorography allows the identification of four intensely labelled proteins with molecular weights of 13,000, 28,000, 29,000, and 30,000. If the iodoacetate labelling is carried out in the presence of nitrosothiol, incorporation is greatly reduced into all components. When germinating spores are labelled with succinate or the lactose analog, o-nitrophenylgalactopyranoside, a significant reduction in the amount of label bound is also observed suggesting that two iodoacetate-reactive sites may be the succinate and lactose permease systems. Severe decreases in the transport of succinate and lactose into iodoacetate and nitrosothiol inhibited spores further implicates a nitrosothiol (iodoacetate) permease interaction. Iodoacetate and nitrosothiols therefore may exert their inhibitory effects by interfering with critical membrane protein sulfhydryl groups, possibly by a a covalent modification mechanism. Some of these sensitive thiols may be involved in active transport processes

  18. Study of the antibacterial effects of chitosans on Bacillus cereus (and its spores) by atomic force microscopy imaging and nanoindentation

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Joao C. [Escola Superior de Biotecnologia, Universidade Catolica Portuguesa, Rua Dr. Antonio Bernardino de Almeida, 4200-072 Porto (Portugal); Eaton, Peter, E-mail: peter.eaton@fc.up.pt [REQUIMTE, Departamento de Quimica, Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal); Gomes, Ana M.; Pintado, Manuela E.; Xavier Malcata, F. [Escola Superior de Biotecnologia, Universidade Catolica Portuguesa, Rua Dr. Antonio Bernardino de Almeida, 4200-072 Porto (Portugal)

    2009-07-15

    Bacillus cereus is a Gram-positive, spore-forming bacterium that is widely distributed in nature. Its intrinsic thermal resistance coupled with the extraordinary resistance against common food preservation techniques makes it one of the most frequent food-poisoning microorganisms causing both intoxications and infections. In order to control B. cereus growth/sporulation, and hence minimize the aforementioned hazards, several antimicrobial compounds have been tested. The aim of this work was to assess by atomic force microscopy (AFM) the relationship between the molecular weight (MW) of chitosan and its antimicrobial activity upon both vegetative and resistance forms of B. cereus. The use of AFM imaging studies helped us to understand how chitosans with different MW act differently upon B. cereus. Higher MW chitosans (628 and 100 kDa) surrounded both forms of B. cereus cells by forming a polymer layer-which eventually led to the death of the vegetative form by preventing the uptake of nutrients yet did not affect the spores since these can survive for extended periods without nutrients. Chitooligosaccharides (COS) (<3 kDa), on the other hand, provoked more visible damages in the B. cereus vegetative form-most probably due to the penetration of the cells by the COS. The use of COS by itself on B. cereus spores was not enough for the destruction of a large number of cells, but it may well weaken the spore structure and its ability to contaminate, by inducing exosporium loss.

  19. Study of the antibacterial effects of chitosans on Bacillus cereus (and its spores) by atomic force microscopy imaging and nanoindentation

    International Nuclear Information System (INIS)

    Bacillus cereus is a Gram-positive, spore-forming bacterium that is widely distributed in nature. Its intrinsic thermal resistance coupled with the extraordinary resistance against common food preservation techniques makes it one of the most frequent food-poisoning microorganisms causing both intoxications and infections. In order to control B. cereus growth/sporulation, and hence minimize the aforementioned hazards, several antimicrobial compounds have been tested. The aim of this work was to assess by atomic force microscopy (AFM) the relationship between the molecular weight (MW) of chitosan and its antimicrobial activity upon both vegetative and resistance forms of B. cereus. The use of AFM imaging studies helped us to understand how chitosans with different MW act differently upon B. cereus. Higher MW chitosans (628 and 100 kDa) surrounded both forms of B. cereus cells by forming a polymer layer-which eventually led to the death of the vegetative form by preventing the uptake of nutrients yet did not affect the spores since these can survive for extended periods without nutrients. Chitooligosaccharides (COS) (<3 kDa), on the other hand, provoked more visible damages in the B. cereus vegetative form-most probably due to the penetration of the cells by the COS. The use of COS by itself on B. cereus spores was not enough for the destruction of a large number of cells, but it may well weaken the spore structure and its ability to contaminate, by inducing exosporium loss.

  20. Phenotypic and Transcriptomic Analyses of Mildly and Severely Salt-Stressed Bacillus cereus ATCC 14579 Cells

    NARCIS (Netherlands)

    Besten, den H.M.W.; Mols, J.M.; Moezelaar, R.; Zwietering, M.H.; Abee, T.

    2009-01-01

    Bacteria are able to cope with the challenges of a sudden increase in salinity by activating adaptation mechanisms. In this study, exponentially growing cells of the pathogen Bacillus cereus ATCC 14579 were exposed to both mild (2.5% [wt/vol] NaCl) and severe (5% [wt/vol] NaCl) salt stress condition

  1. Lessons learnt from a birthday party: a Bacillus cereus outbreak, Bari, Italy, January 2012

    Directory of Open Access Journals (Sweden)

    Domenico Martinelli

    2013-12-01

    Full Text Available INTRODUCTION: Bacillus cereus, a ubiquitous bacterium, can be isolated in various starchy food items, causing both emetic and diarrhoeal disease. The real burden of B. cereus outbreaks is actually poorly known in Italy. We report a B. cereus foodborne outbreak that occurred in a pub in Bari (Italy on January 22nd 2012 during a birthday party, promptly reported by the pub owner. MATERIALS AND METHODS: Between January 22nd and 24th 2012, we performed a retrospective cohort study among the guests of the party to identify risk factors associated with illness. Leftovers of different meals were available for microbiological analysis. Faecal specimens were collected from cases. RESULTS: A total of 12 cases among the 13 customers (attack rate: 92% were reported. All cases had consumed basmati rice and sweet and sour vegetables (aetiological fraction: 100%. B. cereus was isolated from both basmati rice served during the party and faecal specimens. DISCUSSION: The close collaboration between the pub owner and the public health officers and the possibility to test food leftovers and stool samples contributed to prevent further cases.

  2. Plant Compounds Enhance the Assay Sensitivity for Detection of Active Bacillus cereus Toxin

    Directory of Open Access Journals (Sweden)

    Reuven Rasooly

    2015-03-01

    Full Text Available Bacillus cereus is an important food pathogen, producing emetic and diarrheal syndromes, the latter mediated by enterotoxins. The ability to sensitively trace and identify this active toxin is important for food safety. This study evaluated a nonradioactive, sensitive, in vitro cell-based assay, based on B. cereus toxin inhibition of green fluorescent protein (GFP synthesis in transduced monkey kidney Vero cells, combined with plant extracts or plant compounds that reduce viable count of B. cereus in food. The assay exhibited a dose dependent GFP inhibition response with ~25% inhibition at 50 ng/mL toxin evaluated in culture media or soy milk, rice milk or infant formula, products associated with food poisonings outbreak. The plant extracts of green tea or bitter almond and the plant compounds epicatechin or carvacrol were found to amplify the assay response to ~90% inhibition at the 50 ng/mL toxin concentration greatly increasing the sensitivity of this assay. Additional studies showed that the test formulations also inhibited the growth of the B. cereus bacteria, likely through cell membrane disruption. The results suggest that the improved highly sensitive assay for the toxin and the rapid inactivation of the pathogen producing the toxin have the potential to enhance food safety.

  3. Characterization and Metal Detoxification Potential of Moderately Thermophilic Bacillus cereus from Geothermal Springs of Himalaya

    Directory of Open Access Journals (Sweden)

    Aslam Khan Ghalib

    2014-08-01

    Full Text Available Two thermophilic Bacillus cereus strains (B. cereus-TA2 and B. cereus-TA4 used in the present study were isolated from the geothermal spring of Hunza valley, Gilgit, Pakistan. They showed the ability to withstand and grow at high temperature (85°C. Both these strains could resist multiple metals (copper, cadmium, mercury, manganese, zinc, arsenic, chromium and selenium. Strain B. cereus-TA4 reduced Cr (VI at pH 5.0 to 9.0 but maximum reduction (83% was observed at pH 7.0 after 48 h when initially supplied with 200 µg mL-1of K2CrO4. Lower initial concentrations such as 100 µg mL-1 supported higher reduction (90 to 95% than that of high concentration such as 500 µg mL-1 (20 to 30%. Both the strains reduced nearly 70% of Se (IV after 48 h of growth at pH 7.0 when initially supplied with 200 µg mL-1 of Na2SeO3. The optimum temperature for maximum Se (IV reduction was 45°C for both the strains.

  4. Anthrax Toxin-Expressing Bacillus cereus Isolated from an Anthrax-Like Eschar.

    Science.gov (United States)

    Marston, Chung K; Ibrahim, Hisham; Lee, Philip; Churchwell, George; Gumke, Megan; Stanek, Danielle; Gee, Jay E; Boyer, Anne E; Gallegos-Candela, Maribel; Barr, John R; Li, Han; Boulay, Darbi; Cronin, Li; Quinn, Conrad P; Hoffmaster, Alex R

    2016-01-01

    Bacillus cereus isolates have been described harboring Bacillus anthracis toxin genes, most notably B. cereus G9241, and capable of causing severe and fatal pneumonias. This report describes the characterization of a B. cereus isolate, BcFL2013, associated with a naturally occurring cutaneous lesion resembling an anthrax eschar. Similar to G9241, BcFL2013 is positive for the B. anthracis pXO1 toxin genes, has a multi-locus sequence type of 78, and a pagA sequence type of 9. Whole genome sequencing confirms the similarity to G9241. In addition to the chromosome having an average nucleotide identity of 99.98% when compared to G9241, BcFL2013 harbors three plasmids with varying homology to the G9241 plasmids (pBCXO1, pBC210 and pBFH_1). This is also the first report to include serologic testing of patient specimens associated with this type of B. cereus infection which resulted in the detection of anthrax lethal factor toxemia, a quantifiable serum antibody response to protective antigen (PA), and lethal toxin neutralization activity. PMID:27257909

  5. Occurrence and behavior of Bacillus cereus in naturally contaminated ricotta salata cheese during refrigerated storage.

    Science.gov (United States)

    Spanu, Carlo; Scarano, Christian; Spanu, Vincenzo; Pala, Carlo; Casti, Daniele; Lamon, Sonia; Cossu, Francesca; Ibba, Michela; Nieddu, Gavino; De Santis, Enrico P L

    2016-09-01

    The present study shows the fate of Bacillus cereus in refrigerated ricotta salata cheese during shelf-life. 144 ricotta salata cheese belonging to nine naturally contaminated batches were stored refrigerated and analyzed at 24 h, 30, 60 and 90 days of storage. Total bacterial count, B. cereus spores and vegetative forms, intrinsic properties and composition were determined. The presence of spores was sporadic while the prevalence and the level of B. cereus vegetative cells decreased respectively from 83.3 % to 4.65 ± 0.74 cfu g(-1) at the beginning of the observation period to 33.3 % and 1.99 ± 0.55 cfu g(-1) after 90 days. No information is currently available on the fate of B. cereus in ricotta salata. The production process of ricotta salata includes steps such as whey heating followed by slow cooling of clots, which expose to the risk of spore germination and successive growth to levels compatible with toxins production. The prolonged refrigerated storage was not favorable to sporulation, explaining the successive death of vegetative cells. The present study demonstrate the potential risk of food poisoning as consequence of pre-formed emetic toxins in ricotta salata. Food safety of ricotta salata relies on the rapid refrigeration of the product during critical phases for cereulide production. PMID:27217369

  6. Plant compounds enhance the assay sensitivity for detection of active Bacillus cereus toxin.

    Science.gov (United States)

    Rasooly, Reuven; Hernlem, Bradley; He, Xiaohua; Friedman, Mendel

    2015-03-01

    Bacillus cereus is an important food pathogen, producing emetic and diarrheal syndromes, the latter mediated by enterotoxins. The ability to sensitively trace and identify this active toxin is important for food safety. This study evaluated a nonradioactive, sensitive, in vitro cell-based assay, based on B. cereus toxin inhibition of green fluorescent protein (GFP) synthesis in transduced monkey kidney Vero cells, combined with plant extracts or plant compounds that reduce viable count of B. cereus in food. The assay exhibited a dose dependent GFP inhibition response with ~25% inhibition at 50 ng/mL toxin evaluated in culture media or soy milk, rice milk or infant formula, products associated with food poisonings outbreak. The plant extracts of green tea or bitter almond and the plant compounds epicatechin or carvacrol were found to amplify the assay response to ~90% inhibition at the 50 ng/mL toxin concentration greatly increasing the sensitivity of this assay. Additional studies showed that the test formulations also inhibited the growth of the B. cereus bacteria, likely through cell membrane disruption. The results suggest that the improved highly sensitive assay for the toxin and the rapid inactivation of the pathogen producing the toxin have the potential to enhance food safety. PMID:25767986

  7. Isolation and identification of protective compounds from culture media of growing spores of Bacillus cereus

    International Nuclear Information System (INIS)

    A fraction increasing the resistance of resting spores to UV-irradiation and high temperature has been isolated from the culture medium at the stage of B. cereus at. 96 spore initiation. Amino acid analysis, gas chromatography, electrophoresis, and TLC of the products of acidic and alkaline hydrolysis of the isolated fraction demonstrated that the active component of the fraction was the lipoteichoic acid

  8. Antimicrobial activities of tea catechins and theaflavins and tea extracts against Bacillus cereus

    Science.gov (United States)

    We evaluated the antimicrobial activities of seven green tea catechins and four black tea theaflavins, generally referred to as flavonoids, as well as the aqueous extracts (infusions) of 36 commercial black, green, oolong, white, and herbal teas against Bacillus cereus (strain RM3190) incubated at 2...

  9. Genome Sequence of Bacillus cereus Phage vB_BceS-MY192.

    Science.gov (United States)

    Yang, Yong; Zhan, Li; Chen, Jiancai; Zhang, Yunyi; Sun, Yi; Yang, Zhangnv; Jiang, Liping; Zhu, Hanping; Zhang, Yanjun; Lu, Yiyu; Mei, Lingling

    2016-01-01

    ITALIC! Bacillus cereusis an opportunistic foodborne pathogen. The phage vB_BceS-MY192 was isolated from ITALIC! B. cereus192 in a cooked rice sample. The temperate phage belongs to the ITALIC! Siphoviridaefamily, ITALIC! Caudoviralesorder. Here we announce the phage genome sequence and its annotation, which may expand the understanding of ITALIC! B. cereussiphophages. PMID:27103733

  10. The potential of flow cytometry in the study of Bacillus cereus.

    Science.gov (United States)

    Cronin, U P; Wilkinson, M G

    2010-01-01

    Flow cytometry (FCM) is a rapid method allowing the acquisition of multiparametric data from thousands of individual cells within a sample. As well as measuring the intrinsic light scattering properties of cells, a plethora of fluorescent dyes may be employed to yield information on macromolecule content, surface antigens present or physiological status. Despite FCM's indispensability within other fields e.g. immunology, it is underutilized within microbiological research. In this review, a strong case is presented for the potential of FCM in the study of Gram-positive spore-former, Bacillus cereus. Previous reports where FCM was successfully used in the study of B. cereus are reviewed along with relevant studies involving other members of the genus. Under headings reflecting common research themes associated with B. cereus, specific instances where FCM has generated novel data, providing a unique insight into the organism, are discussed. Further applications are posited, based on the authors' own research with FCM and B. cereus and work extant in the broader field of microbial cytometry. The authors conclude that, while the expense of equipment and reagents is an undeniable disadvantage, FCM is a technique capable of generating significantly novel data and allows the design and execution of experiments that are not possible with any other technique. PMID:19486207

  11. A quantitative microbiological exposure assessment model for Bacillus cereus in REPFEDs.

    Science.gov (United States)

    Daelman, Jeff; Membré, Jeanne-Marie; Jacxsens, Liesbeth; Vermeulen, An; Devlieghere, Frank; Uyttendaele, Mieke

    2013-09-16

    One of the pathogens of concern in refrigerated and processed foods of extended durability (REPFED) is psychrotrophic Bacillus cereus, because of its ability to survive pasteurisation and grow at low temperatures. In this study a quantitative microbiological exposure assessment (QMEA) of psychrotrophic B. cereus in REPFEDs is presented. The goal is to quantify (i) the prevalence and concentration of B. cereus during production and shelf life, (ii) the number of packages with potential emetic toxin formation and (iii) the impact of different processing steps and consumer behaviour on the exposure to B. cereus from REPFEDs. The QMEA comprises the entire production and distribution process, from raw materials over pasteurisation and up to the moment it is consumed or discarded. To model this process the modular process risk model (MPRM) was used (Nauta, 2002). The product life was divided into nine modules, each module corresponding to a basic process: (1) raw material contamination, (2) cross contamination during handling, (3) inactivation during preparation, (4) growth during intermediate storage, (5) partitioning of batches in portions, (6) mixing portions to create the product, (7) recontamination during assembly and packaging, (8) inactivation during pasteurisation and (9) growth during shelf life. Each of the modules was modelled and built using a combination of newly gathered and literature data, predictive models and expert opinions. Units (batch/portion/package) with a B. cereus concentration of 10(5)CFU/g or more were considered 'risky' units. Results show that the main drivers of variability and uncertainty are consumer behaviour, strain variability and modelling error. The prevalence of B. cereus in the final products is estimated at 48.6% (±0.01%) and the number of packs with too high B. cereus counts at the moment of consumption is estimated at 4750 packs per million (0.48%). Cold storage at retail and consumer level is vital in limiting the exposure

  12. Crystallization and preliminary X-ray crystallographic analysis of peptide deformylase (PDF) from Bacillus cereus in ligand-free and actinonin-bound forms

    International Nuclear Information System (INIS)

    Peptide deformylase (PDF) from B. cereus has been overexpressed, purified and crystallized in ligand-free and actinonin-bound forms. Diffraction data have been collected from these crystals to 1.7 and 2.0 Å resolution, respectively. In bacteria, protein expression initiates with an N-formyl group and this needs to be removed in order to ensure proper bacterial growth. These formylation and deformylation processes are unique to eubacteria; therefore, inhibition of these would provide a novel antibacterial therapy. Deformylation is carried out by peptide deformylase (PDF). PDF from Bacillus cereus, one of the major pathogenic bacteria, was cloned into expression plasmid pET-28a (Novagen), overexpressed in Escherichia coli BL21 (DE3) and purified to high quality. Crystals have been obtained of both ligand-free PDF and PDF to which actinonin, a highly potent naturally occurring inhibitor, is bound. Both crystals belong to space group P212121, with unit-cell parameters a = 42.72, b = 44.04, c = 85.19 Å and a = 41.31, b = 44.56, c = 84.47 Å, respectively. Diffraction data were collected to 1.7 Å resolution for the inhibitor-free crystals and to 2.0 Å resolution for the actinonin-bound crystals

  13. Crystallization and preliminary X-ray data analysis of the pXO1 plasmid-partitioning factor TubZ from Bacillus cereus

    International Nuclear Information System (INIS)

    B. cereus TubZ was cocrystallized with GDP and diffraction data were collected to 2.1 Å resolution. TubZ is a structural homologue of tubulin and FtsZ GTPases, which are involved in the type III plasmid-partitioning system. TubZ assembles into polymers in a GTP-dependent manner and drives plasmid segregation as ‘cytomotive’ filaments. In this study, C-terminally truncated TubZ from Bacillus cereus was crystallized in the presence or absence of GDP by the hanging-drop vapour-diffusion method. The crystal of TubZ in complex with GDP belonged to the monoclinic space group P21, with unit-cell parameters a = 67.05, b = 84.49, c = 67.66 Å, β = 92.92°, and was non-isomorphous with GDP-bound TubZ previously crystallized in the presence of the slowly hydrolysable GTP analogue GTPγS. TubZ was also crystallized in the free form and the crystal belonged to space group P21, with unit-cell parameters a = 53.91, b = 65.54, c = 58.18 Å, β = 106.19°. Data were collected to 1.7 and 2.1 Å resolution for the free and GDP-bound forms, respectively

  14. Inactivation of Enterobacter sakazakii, Bacillus cereus, and Salmonella typhimurium in powdered weaning food by electron-beam irradiation

    International Nuclear Information System (INIS)

    Inactivation of Enterobacter sakazakii, Bacillus cereus, and Salmonella typhimurium were evaluated in powdered weaning food using electron-beam irradiation. E. sakazakii, B. cereus, and S. typhimurium were eliminated by irradiation at 16, 8, and 8 kGy, respectively. The D10-vlaues of E. sakazakii, B. cereus, and S. typhimurium inoculated on powdered weaning food were 4.83, 1.22, and 0.98 kGy, respectively. The results suggest that electron-beam irradiation should inhibit the growth of pathogenic bacteria on baby food without impairing qualities

  15. Inactivation of Enterobacter sakazakii, Bacillus cereus, and Salmonella typhimurium in powdered weaning food by electron-beam irradiation

    Science.gov (United States)

    Hong, Yun-Hee; Park, Ji-Yong; Park, Jong-Hyun; Chung, Myong-Soo; Kwon, Ki-Sung; Chung, Kyungsook; Won, Misun; Song, Kyung-Bin

    2008-09-01

    Inactivation of Enterobacter sakazakii, Bacillus cereus, and Salmonella typhimurium were evaluated in powdered weaning food using electron-beam irradiation. E. sakazakii, B. cereus, and S. typhimurium were eliminated by irradiation at 16, 8, and 8 kGy, respectively. The D10-vlaues of E. sakazakii, B. cereus, and S. typhimurium inoculated on powdered weaning food were 4.83, 1.22, and 0.98 kGy, respectively. The results suggest that electron-beam irradiation should inhibit the growth of pathogenic bacteria on baby food without impairing qualities.

  16. Transitory UV resistance during germination of UV-sensitive spores produced by a mutant of Bacillus cereus 569

    International Nuclear Information System (INIS)

    A mutant of Bacillus cereus 569, designated 2422 is unable to excise cyclobutane-type dimers and spore-specific photoproducts from the DNA of UV-irradiated vegetative cells and dormant spores. The deficiency in the excision repair mechanism was found to be at the post-incision step in the exonuclease-mediated removal of the photoproducts. During germination, the mutant B. cereus 2422 exhibits UV-resistance and an efficient photoproduct removal which is followed by DNA repair synthesis. The data presented indicate the existence of germinative excision repair in B. cereus 569. (author)

  17. A microbial method of geochemical exploration. A study of using soil bacillus cereus method to prospect for Au and U

    International Nuclear Information System (INIS)

    The mineral exploration using Bacillus cereus in soils belongs to the microbial geochemistry. This paper deals with exploration principle, field operation procedure, measurement techniques in laboratory, geological effectiveness of preliminary test in the field and some problems in the measurement that must be noted using Bacellus cereus in soils method. Obvious Bacellus cereus counts of anomalies were measured in known concealed gold deposits (occurrences) and uranium deposits (occurrences). In addition, a test was made in the potential area of uranium mineralization in the periphery of uranium (molybdenum) deposit and the geological effectiveness are more ideal

  18. Bacillus cereus septicemia in a patient with acute lymphoblastic leukemia: A case report and review of the literature.

    Science.gov (United States)

    Chou, Ya-Ling; Cheng, Shin-Nan; Hsieh, Kao-Hsian; Wang, Chih-Chien; Chen, Shyi-Jou; Lo, Wen-Tsung

    2013-08-01

    Bacillus cereus is an aerobic Gram-positive, spore-forming, rod-shaped bacterium that is responsible for foodborne illnesses. We report on a 15-year-old girl with B-cell acute lymphoblastic leukemia, who fell into a somnolent state after presenting with a 12-hour history of fever, muscle soreness, myalgia in both calves, sore throat, and vomiting. Fulminant septicemic syndrome caused by B. cereus was finally identified. The aim of this work is the introduction of B. cereus as a differential diagnosis of sepsis in patients with acute leukemia in induction chemotherapy, to prevent delayed treatment. PMID:23927823

  19. Inactivation of Bacillus cereus vegetative cells by gastric acid and bile during in vitro gastrointestinal transit

    Directory of Open Access Journals (Sweden)

    Ceuppens Siele

    2012-10-01

    Full Text Available Abstract Background The foodborne pathogen Bacillus cereus can cause diarrhoeal food poisoning by production of enterotoxins in the small intestine. The prerequisite for diarrhoeal disease is thus survival during gastrointestinal passage. Methods Vegetative cells of 3 different B. cereus strains were cultivated in a real composite food matrix, lasagne verde, and their survival during subsequent simulation of gastrointestinal passage was assessed using in vitro experiments simulating transit through the human upper gastrointestinal tract (from mouth to small intestine. Results No survival of vegetative cells was observed, despite the high inoculum levels of 7.0 to 8.0 log CFU/g and the presence of various potentially protective food components. Significant fractions (approx. 10% of the consumed inoculum of B. cereus vegetative cells survived gastric passage, but they were subsequently inactivated by bile exposure in weakly acidic intestinal medium (pH 5.0. In contrast, the low numbers of spores present (up to 4.0 log spores/g showed excellent survival and remained viable spores throughout the gastrointestinal passage simulation. Conclusion Vegetative cells are inactivated by gastric acid and bile during gastrointestinal passage, while spores are resistant and survive. Therefore, the physiological form (vegetative cells or spores of the B. cereus consumed determines the subsequent gastrointestinal survival and thus the infective dose, which is expected to be much lower for spores than vegetative cells. No significant differences in gastrointestinal survival ability was found among the different strains. However, considerable strain variability was observed in sporulation tendency during growth in laboratory medium and food, which has important implications for the gastrointestinal survival potential of the different B. cereus strains.

  20. Comparative Bioinformatics and Experimental Analysis of the Intergenic Regulatory Regions of Bacillus cereus hbl and nhe Enterotoxin Operons and the Impact of CodY on Virulence Heterogeneity.

    Science.gov (United States)

    Böhm, Maria-Elisabeth; Krey, Viktoria M; Jeßberger, Nadja; Frenzel, Elrike; Scherer, Siegfried

    2016-01-01

    Bacillus cereus is a food contaminant with greatly varying enteropathogenic potential. Almost all known strains harbor the genes for at least one of the three enterotoxins Nhe, Hbl, and CytK. While some strains show no cytotoxicity, others have caused outbreaks, in rare cases even with lethal outcome. The reason for these differences in cytotoxicity is unknown. To gain insight into the origin of enterotoxin expression heterogeneity in different strains, the architecture and role of 5' intergenic regions (5' IGRs) upstream of the nhe and hbl operons was investigated. In silico comparison of 142 strains of all seven phylogenetic groups of B. cereus sensu lato proved the presence of long 5' IGRs upstream of the nheABC and hblCDAB operons, which harbor recognition sites for several transcriptional regulators, including the virulence regulator PlcR, redox regulators ResD and Fnr, the nutrient-sensitive regulator CodY as well as the master regulator for biofilm formation SinR. By determining transcription start sites, unusually long 5' untranslated regions (5' UTRs) upstream of the nhe and hbl start codons were identified, which are not present upstream of cytK-1 and cytK-2. Promoter fusions lacking various parts of the nhe and hbl 5' UTR in B. cereus INRA C3 showed that the entire 331 bp 5' UTR of nhe is necessary for full promoter activity, while the presence of the complete 606 bp hbl 5' UTR lowers promoter activity. Repression was caused by a 268 bp sequence directly upstream of the hbl transcription start. Luciferase activity of reporter strains containing nhe and hbl 5' IGR lux fusions provided evidence that toxin gene transcription is upregulated by the depletion of free amino acids. Electrophoretic mobility shift assays showed that the branched-chain amino acid sensing regulator CodY binds to both nhe and hbl 5' UTR downstream of the promoter, potentially acting as a nutrient-responsive roadblock repressor of toxin gene transcription. PlcR binding sites are

  1. Comparative Bioinformatics and Experimental Analysis of the Intergenic Regulatory Regions of Bacillus cereus hbl and nhe Enterotoxin Operons and the Impact of CodY on Virulence Heterogeneity

    Science.gov (United States)

    Böhm, Maria-Elisabeth; Krey, Viktoria M.; Jeßberger, Nadja; Frenzel, Elrike; Scherer, Siegfried

    2016-01-01

    Bacillus cereus is a food contaminant with greatly varying enteropathogenic potential. Almost all known strains harbor the genes for at least one of the three enterotoxins Nhe, Hbl, and CytK. While some strains show no cytotoxicity, others have caused outbreaks, in rare cases even with lethal outcome. The reason for these differences in cytotoxicity is unknown. To gain insight into the origin of enterotoxin expression heterogeneity in different strains, the architecture and role of 5′ intergenic regions (5′ IGRs) upstream of the nhe and hbl operons was investigated. In silico comparison of 142 strains of all seven phylogenetic groups of B. cereus sensu lato proved the presence of long 5′ IGRs upstream of the nheABC and hblCDAB operons, which harbor recognition sites for several transcriptional regulators, including the virulence regulator PlcR, redox regulators ResD and Fnr, the nutrient-sensitive regulator CodY as well as the master regulator for biofilm formation SinR. By determining transcription start sites, unusually long 5′ untranslated regions (5′ UTRs) upstream of the nhe and hbl start codons were identified, which are not present upstream of cytK-1 and cytK-2. Promoter fusions lacking various parts of the nhe and hbl 5′ UTR in B. cereus INRA C3 showed that the entire 331 bp 5′ UTR of nhe is necessary for full promoter activity, while the presence of the complete 606 bp hbl 5′ UTR lowers promoter activity. Repression was caused by a 268 bp sequence directly upstream of the hbl transcription start. Luciferase activity of reporter strains containing nhe and hbl 5′ IGR lux fusions provided evidence that toxin gene transcription is upregulated by the depletion of free amino acids. Electrophoretic mobility shift assays showed that the branched-chain amino acid sensing regulator CodY binds to both nhe and hbl 5′ UTR downstream of the promoter, potentially acting as a nutrient-responsive roadblock repressor of toxin gene transcription. Plc

  2. Crystalliferous Bacillus cereus group bacteria from a Maryland hardwood forest are dominated by psychrotolerant strains

    Science.gov (United States)

    Crystal forming Bacillus spp. were isolated from soil samples collected at different elevations within a mixed hardwood forest in central Maryland, and their phylogenetic relationships determined by multilocus sequence analysis. The vast majority of isolates obtained were associated with two phylog...

  3. Crystallization and preliminary X-ray crystallographic studies of a PduO-type ATP:cob(I)alamin adenosyltransferase from Bacillus cereus

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ae Kyung [Division of Biotechnology, College of Life Sciences, Korea University, Seoul 136-713 (Korea, Republic of); Moon, Jin Ho [Insititute of Life Sciences and Natural Resources, Korea University, Seoul 136-713 (Korea, Republic of); Lee, Sung Haeng [Department of Medicine, Medical Research Center (MRC), College of Medicine, Chosun University, Gwangju 501-759 (Korea, Republic of); Chi, Young Min, E-mail: ezeg@korea.ac.kr [Division of Biotechnology, College of Life Sciences, Korea University, Seoul 136-713 (Korea, Republic of)

    2008-07-01

    Orthorhombic crystals of a PduO-type ATP:cob(I)alamin adenosyltransferase from B. cereus were obtained both as an apoenzyme and in the presence of Mg{sup 2+} and ATP. Cobalamin adenosyltransferases transfer a 5′-deoxyadenosyl moiety from ATP and covalently attach it to the cobalt(I) ion of the corrin ring of cobalamin to generate adenosylcobalamin. The PduO-type adenosyltransferase from Bacillus cereus was overexpressed in Escherichia coli, purified and crystallized as the apoenzyme as well as in complex with Mg{sup 2+} and ATP (MgATP). Diffraction data were collected to 1.9 Å resolution for the native crystals and 2.0 Å resolution for the complexed crystals. Both crystals belonged to the orthorhombic space group C222{sub 1}; the native crystals have unit-cell parameters a = 64.93, b = 137.08, c = 158.55 Å. The asymmetric unit contained one trimer, with a corresponding V{sub M} of 2.69 Å{sup 3} Da{sup −1}.

  4. Crystallization and preliminary X-ray crystallographic studies of a PduO-type ATP:cob(I)alamin adenosyltransferase from Bacillus cereus

    International Nuclear Information System (INIS)

    Orthorhombic crystals of a PduO-type ATP:cob(I)alamin adenosyltransferase from B. cereus were obtained both as an apoenzyme and in the presence of Mg2+ and ATP. Cobalamin adenosyltransferases transfer a 5′-deoxyadenosyl moiety from ATP and covalently attach it to the cobalt(I) ion of the corrin ring of cobalamin to generate adenosylcobalamin. The PduO-type adenosyltransferase from Bacillus cereus was overexpressed in Escherichia coli, purified and crystallized as the apoenzyme as well as in complex with Mg2+ and ATP (MgATP). Diffraction data were collected to 1.9 Å resolution for the native crystals and 2.0 Å resolution for the complexed crystals. Both crystals belonged to the orthorhombic space group C2221; the native crystals have unit-cell parameters a = 64.93, b = 137.08, c = 158.55 Å. The asymmetric unit contained one trimer, with a corresponding VM of 2.69 Å3 Da−1

  5. Effect of endophytic Bacillus cereus ERBP inoculation into non-native host: Potentials and challenges for airborne formaldehyde removal.

    Science.gov (United States)

    Khaksar, Gholamreza; Treesubsuntorn, Chairat; Thiravetyan, Paitip

    2016-10-01

    Phytoremediation could be a cost-effective, environmentally friendly approach for the treatment of indoor air. However, some drawbacks still dispute the expediency of phytotechnology. Our objectives were to investigate the competency of plant growth-promoting (PGP) endophytic Bacillus cereus ERBP (endophyte root blue pea), isolated from the root of Clitoria ternatea, to colonize and stabilize within Zamioculcas zamiifolia and Euphorbia milii as non-native hosts without causing any disease or stress symptoms. Moreover, the impact of B. cereus ERBP on the natural shoot endophytic community and for the airborne formaldehyde removal capability of non-native hosts was assessed. Non-native Z. zamiifolia was effectively inoculated with B. cereus ERBP through soil as the most efficient method of endophyte inoculation. Denaturing gradient gel electrophoresis profiling of the shoot endophytic community verified the colonization and stability of B. cereus ERBP within its non-native host during a 20-d fumigation period without interfering with the natural shoot endophytic diversity of Z. zamiifolia. B. cereus ERBP conferred full protection to its non-native host against formaldehyde phytotoxicity and enhanced airborne formaldehyde removal of Z. zamiifolia whereas non-inoculated plants suffered from formaldehyde phytotoxicity because their natural shoot endophytic community was detrimentally affected by formaldehyde. In contrast, B. cereus ERBP inoculation into non-native E. milii deteriorated airborne formaldehyde removal of the non-native host (compared to a non-inoculated one) as B. cereus ERBP interfered with natural shoot endophytic community of E. milii, which caused stress symptoms and stimulated ethylene biosynthesis. Non-native host inoculation with PGP B. cereus ERBP could bear potentials and challenges for airborne formaldehyde removal. PMID:27362296

  6. Bacillus cereus AR156-Induced Resistance to Colletotrichum acutatum Is Associated with Priming of Defense Responses in Loquat Fruit

    OpenAIRE

    Wang, Xiaoli; Wang, Lei; Wang, Jing; Jin, Peng; Liu, Hongxia; Zheng, Yonghua

    2014-01-01

    The effectiveness of a biocontrol agent Bacillus cereus AR156 for control of anthracnose rot caused by Colletotrichum acutatum in harvested loquat fruit and the possible mechanisms of its action have been investigated. Treatment of fruit with B. cereus AR156 resulted in lower disease incidence and smaller lesion diameters compared with that of untreated fruit. The treatment enhanced activities of defense-related enzymes including chitinase, β-1, 3-glucanase, phenylalanine ammonia-lyase, perox...

  7. Effects of nisin and temperature on survival, growth, and enterotoxin production characteristics of psychrotrophic Bacillus cereus in beef gravy.

    OpenAIRE

    Beuchat, L. R.; Clavero, M R; Jaquette, C B

    1997-01-01

    The presence of psychrotrophic enterotoxigenic Bacillus cereus in ready-to-serve meats and meat products that have not been subjected to sterilization treatment is a public health concern. A study was undertaken to determine the survival, growth, and diarrheal enterotoxin production characteristics of four strains of psychrotrophic B. cereus in brain heart infusion (BHI) broth and beef gravy as affected by temperature and supplementation with nisin. A portion of unheated vegetative cells from...

  8. Bacillus cereus in Infant Foods: Prevalence Study and Distribution of Enterotoxigenic Virulence Factors in Isfahan Province, Iran

    OpenAIRE

    Ebrahim Rahimi; Fahimeh Abdos; Hassan Momtaz; Zienab Torki Baghbadorani; Mohammad Jalali

    2013-01-01

    This study was carried out in order to investigate the presences of Bacillus cereus and its enterotoxigenic genes in infant foods in Isfahan, Iran. Overall 200 infant foods with various based were collected and immediately transferred to the laboratory. All samples were culture and the genomic DNA was extracted from colonies with typical characters of Bacillus cereus. The presences of enterotoxigenic genes were investigated using the PCR technique. Eighty-four of two hundred samples (42%) wer...

  9. Spontaneous Bacterial Peritonitis (SBP) caused by Bacillus Cereus in an Alcoholic Patient: Case Report and Review of Literature

    OpenAIRE

    Bhattacharyya, Sayan; Ansari, Mohammad Aftab Alam; Sarfraz, Asim; Jaiswal, Nitesh; Singh, Siddharth

    2015-01-01

    Spontaneous bacterial peritonitis (SBP) is infection of peritoneal covering of the abdomen caused by bacteria, without any known etiology. Common known predisposing factors are cirrhosis of liver and old age among others. Bacillus cereus is an uncommon cause of SBP and often wrongly interpreted as a contaminant. We hereby report a case of peritonitis in chronic alcoholic, elderly male patient presenting in the outpatient department. Bacillus cereus is often regarded as contaminant but must be...

  10. Differentiation Between Bacillus thuringiensis and Bacillus cereus by 16S rDNA-PCR and ERIC-PCR

    Institute of Scientific and Technical Information of China (English)

    LI Haitao; LIU Dongming; GAO Jiguo

    2011-01-01

    16S rDNA and ERIC (Enterobacteia Repetitive Intergenic Consensus Sequences) based on PCR method were tested for the effectiveness of the differentiation of B. thuringiensis and B. cereus. 16S rDNA-PCR primers were designed based on the sequence difference in variable regions of B. cereus 16S rDNA and B. thuringiensis 16S rDNA, 16S rDNA-PCR showed no obvious difference between B. cereus and B. thuringiensis. The only difference was that one 1600-bp amplificon could be obtained from all the three B. Cereus strains, and none amplificon from any B. thuringiensis strains. ERIC was optimized based on previous reports. The genonlic DNA was used for the template of ER1C-PCR, and the following DNA fingerprints were analyzed by the agarose gel electrophoresis. The results showed that DNA fingerprint of three B. thuringiensis strains had a unique amplicon less than 100-bp, while DNA fingerprint of three B. cereus" strains had none. Moreover, DNA fingerprint of B. cereus showed a 700-bp amplicon, but didn't have any DNA fingerprints ofB. thuringiensis genome. Therefore, ERIC-PCR technique should be able to be used for the differentiation of B. thuringiensis and B. cereus.

  11. Root exudate-induced alterations in Bacillus cereus cell wall contribute to root colonization and plant growth promotion.

    Directory of Open Access Journals (Sweden)

    Swarnalee Dutta

    Full Text Available The outcome of an interaction between plant growth promoting rhizobacteria and plants may depend on the chemical composition of root exudates (REs. We report the colonization of tobacco, and not groundnut, roots by a non-rhizospheric Bacillus cereus (MTCC 430. There was a differential alteration in the cell wall components of B. cereus in response to the REs from tobacco and groundnut. Attenuated total reflectance infrared spectroscopy revealed a split in amide I region of B. cereus cells exposed to tobacco-root exudates (TRE, compared to those exposed to groundnut-root exudates (GRE. In addition, changes in exopolysaccharides and lipid-packing were observed in B. cereus grown in TRE-amended minimal media that were not detectable in GRE-amended media. Cell-wall proteome analyses revealed upregulation of oxidative stress-related alkyl hydroperoxide reductase, and DNA-protecting protein chain (Dlp-2, in response to GRE and TRE, respectively. Metabolism-related enzymes like 2-amino-3-ketobutyrate coenzyme A ligase and 2-methylcitrate dehydratase and a 60 kDa chaperonin were up-regulated in response to TRE and GRE. In response to B. cereus, the plant roots altered their exudate-chemodiversity with respect to carbohydrates, organic acids, alkanes, and polyols. TRE-induced changes in surface components of B. cereus may contribute to successful root colonization and subsequent plant growth promotion.

  12. ENUMERATION OF Bacillus cereus IN “FUBÁ” OF CORN (Zea mays. L. ENUMERAÇÃO DE Bacillus cereus EM FUBÁ DE MILHO (Zea mays L.

    Directory of Open Access Journals (Sweden)

    Albenones José de Mesquita

    2007-09-01

    Full Text Available

    A hundred (100 samples of “fubá” were examined, in relation to the incidence of Bacillus cereus, obtained by different technological processes (common “fubá” and previously cooked “fubá” and sold in the retail market in Goiânia - GO. The results of the examination showed that 23% of the samples was contaminated, of this percentual, 39.1% of the contaminations occurred in samples of previously cooked “fubá” and 60.9% in samples of common “fubá”. This in relation of the two products clearly showed the more accurate technological process that the previously cooked “fubá” was brought under. It was also observed that the totality of the analyzed samples showed enumerations below the limit established by the Brazilian microbiologic standard that establishes a limit of 10³ cells of Bacillus cereus for a gram of the food.

    Foram examinadas 100 amostras de fubá de milho, em relação à incidência de Bacillus cereus, obtidas através de processamentos tecnológicos diferentes (fubá comum e fubá pré-cozido e comercializadas no mercado varejista de Goiânia - GO. Os resultados revelaram que 23% das amostras estavam contaminadas, deste percentual, 39,1% das contaminações ocorreram em amostras de fubá pré-cozido e 60,9%, em amostras de fubá comum. Esta considerável diferença, observada em termos percentuais em relação aos dois produtos evidenciou o processamento tecnológico mais rigoroso a que foi submetido o fubá pré-cozido. Observou-se, também, que a totalidade das amostras analisadas apresentou enumerações abaixo do limite estabelecido pelo padrão microbiológico brasileiro que determina um limite de 10³ células de B. cereus por gama do alimento.

  13. Antimicrobial potential of flavoring ingredients against Bacillus cereus in a milk-based beverage.

    Science.gov (United States)

    Pina-Pérez, Maria C; Rodrigo, Dolores; Martínez-López, Antonio

    2013-11-01

    Natural ingredients--cinnamon, cocoa, vanilla, and anise--were assessed based on Bacillus cereus vegetative cell growth inhibition in a mixed liquid whole egg and skim milk beverage (LWE-SM), under different conditions: ingredient concentration (1, 2.5, and 5% [wt/vol]) and incubation temperature (5, 10, and 22 °C). According to the results obtained, ingredients significantly (pCinnamon was the most bacteriostatic ingredient and cocoa the most bactericidal one when they were added at 5% (wt/vol) and beverages were incubated at 5 °C. The bactericidal effect of cocoa 5% (wt/vol) reduced final B. cereus log10 counts (log Nf, log10 (colony-forming units/mL)) by 4.10 ± 0.21 log10 cycles at 5 °C. PMID:23909775

  14. Lactoferrin and transferrin fragments react with nitrite to form an inhibitor of Bacillus cereus spore outgrowth.

    OpenAIRE

    Custer, M C; Hansen, J N

    1983-01-01

    Tryptone is a pancreatic digest of casein which contains a heterogeneous mixture of substances that react with nitrite when heated in the presence of sodium thioglycolate to form a bacteriostatic agent which inhibits outgrowth of Bacillus cereus T spores. The substances which are precursors to the bacteriostatic agent can be fractionated on the basis of molecular size and charge and have properties which indicate that they are fragments of lactoferrin, an iron-binding glycoprotein. The bacter...

  15. Production of fungal protein by solid substrate fermentation of cactus Cereus peruvianus and Opuntia ficus indica

    OpenAIRE

    Moises A. Oliveira; Claudenice Rodrigues; Edson Marques dos Reis; Jorge Nozaki

    2001-01-01

    Agricultural wastes from cactus Cereus peruvianus and Opuntia ficus indica were investigated for protein production by solid substrate fermentation. Firstly, the polyelectrolytes were extracted and used in water cleaning as auxiliary of flocculation and coagulation. The remaining fibrous material and peels were used as substrate for fermentation with Aspergillus niger. Glucoamylase and cellulase were the main enzymes produced. Amino acids were determined by HPLC and protein by Lowry's method....

  16. Isolation, identification and characterization of Bacillus cereus from the dairy environment.

    OpenAIRE

    te Giffel, M.C.

    1997-01-01

    In this thesis the occurrence of Bacillus cereus in the milk production and processing environment was investigated. Isolates were identified biochemically and by DNA probes based on the variable regions of 16S rRNA. Further characterization was carried out using biochemical and molecular typing, in order to determine the major contamination sources of milk. Furthermore, properties in relation to carbohydrate utilization, growth at low temperatures and enterotoxin production were examined.B. ...

  17. Tracking cereulide producing Bacillus cereus in foods, papermaking and biowaste management

    OpenAIRE

    Hoornstra, Douwe

    2014-01-01

    Bacillus cereus is a ubiquitous food poisoning bacterium, but only producers of the emetic toxin, cereulide can be life threatening. Therefore a fast and reliable method is needed for identifying strains that produce the toxin. In this thesis the previously developed sperm bioassay was refined into a tool for the detection of microbially produced mitochondria toxic substances. This refined tool, Sperm Combi Assay effectively detected not only cereulide, but also other mitochondrial toxic subs...

  18. Conjugation in Bacillus cereus: how does the biofilm lifestyle impact on transfer efficiency?

    OpenAIRE

    Vanzieleghem, Thomas; Modrie, Pauline; Mahillon, Jacques; IWA : Processes in Biofilms

    2011-01-01

    Bacterial evolution has mainly been driven by Horizontal Gene Tranfers (HGT). Among these, conjugation and mobilization have been described for over fifty years, in liquid media. However, it is now generally admitted that, in nature, bacteria are mostly found in interface-associated communities. The perspective of elucidating how the biofilm lifestyle impacts on HGT has recently gained in interest. This study focused on surface colonizer Bacillus cereus sensu lato, an opportunistic food-borne...

  19. Transcriptional responses of Bacillus cereus towards challenges with the polysaccharide chitosan

    OpenAIRE

    Hilde Mellegård; Ákos T Kovács; Toril Lindbäck; Christensen, Bjørn E.; Kuipers, Oscar P.; Granum, Per E.

    2011-01-01

    The antibacterial activity of the polysaccharide chitosan towards different bacterial species has been extensively documented. The response mechanisms of bacteria exposed to this biopolymer and the exact molecular mechanism of action, however, have hardly been investigated. This paper reports the transcriptome profiling using DNA microarrays of the type-strain of Bacillus cereus (ATCC 14579) exposed to subinhibitory concentrations of two water-soluble chitosan preparations with defined chemic...

  20. Evaluation of Bacillus cereus and Bacillus pumilus metabolites for anthelmintic activity

    OpenAIRE

    M L Vijaya Kumar; Thippeswamy, B.; I L Kuppust; Naveenkumar, K. J.; C K Shivakumar

    2015-01-01

    Objective: To assess the anthelmintic acivity of Bacillus cereus and Bacillus pumilus metabolites. Materials and Methods: The successive solvent extractions with petroleum ether, ethyl acetate and methanol. The solvent extracts were tested for anthelmintic activity against Pheretima posthuma at 20 mg/ml concentration. The time of paralysis and time of death of the worms was determined for all the extracts. Albendazole was taken as a standard reference and sterile water as a control. Results: ...

  1. Successful Treatment of Bacillus cereus Bacteremia in a Patient with Propionic Acidemia

    OpenAIRE

    Aygun, Fatma Deniz; Aygun, Fatih; Cam, Halit

    2016-01-01

    Bacillus cereus can cause serious, life-threatening, systemic infections in immunocompromised patients. The ability of microorganism to form biofilm on biomedical devices can be responsible for catheter-related bloodstream infections. Other manifestations of severe disease are meningitis, endocarditis, osteomyelitis, and surgical and traumatic wound infections. The most common feature in true bacteremia caused by Bacillus is the presence of an intravascular catheter. Herein, we report a case ...

  2. EXAFS investigation of uranium(VI) complexes formed at Bacillus cereus and Bacillus sphaericus surfaces

    International Nuclear Information System (INIS)

    Uranium(VI) complex formation at vegetative cells and spores of Bacillus cereus and Bacillus sphaericus was studied using uranium LII-edge and LIII-edge extended X-ray absorption fine structure (EXAFS) spectroscopy. A comparison of the measured equatorial U-O distances and other EXAFS structural parameters of uranyl species formed at the Bacillus strains with those of the uranyl structure family indicates that the uranium is predominantly bound as uranyl complexes with phosphoryl residues. (orig.)

  3. Biofilm Formation by Bacillus cereus Is Influenced by PlcR, a Pleiotropic Regulator

    OpenAIRE

    Hsueh, Yi-Huang; Somers, Eileen B.; Lereclus, Didier; Wong, Amy C. Lee

    2006-01-01

    The ΔplcR mutant of Bacillus cereus strain ATCC 14579 developed significantly more biofilm than the wild type and produced increased amounts of biosurfactant. Biosurfactant production is required for biofilm formation and may be directly or indirectly repressed by PlcR, a pleiotropic regulator. Coating polystyrene plates with surfactin, a biosurfactant from Bacillus subtilis, rescued the deficiency in biofilm formation by the wild type.

  4. L-asparaginase production by mangrove derived Bacillus cereus MAB5:optimization by response surface methodology

    Institute of Scientific and Technical Information of China (English)

    ThenmozhiC; SankarR; KaruppiahV; SampathkumarP

    2011-01-01

    Objective:To isolate marine bacteria, statistically optimize them for maximum asparaginase production. Methods:In the present study, statistically based experimental designs were applied to maximize the production of L-asparaginase from bacterial strain of Bacillus cereus (B. cereus) MAB5 (HQ675025) isolated and identified by 16S rDNA sequencing from mangroves rhizosphere sediment. Results:Plackett-Barman design was used to identify the interactive effect of the eight variables viz. yeast extract, soyabean meal, glucose, magnesium sulphate, KH2PO4, wood chips, aspargine and sodium chloride. All the variables are denoted as numerical factors and investigated at two widely spaced intervals designated as-1 (low level) and+1 (high level). The effect of individual parameters on L-asparaginase production was calculated. Soyabean meal, aspargine, wood chips and sodium chloride were found to be the significant among eight variables. The maximum amount of L-asparaginase produced (51.54 IU/mL) from the optimized medium containing soyabean meal (6.282 8 g/L), aspargine (5.5 g/L), wood chips (1.383 8 g/L) and NaCl (4.535 4 g/L). Conclusions:The study revealed that, it is useful to produce the maximum amount of L-asparaginase from B. cereus MAB5 for the treatment of various infections and diseases.

  5. Arsenic release by indigenous bacteria Bacillus cereus from aquifer sediments at Datong Basin, northern China

    Science.gov (United States)

    Xie, Zuoming; Wang, Yanxin; Duan, Mengyu; Xie, Xianjun; Su, Chunli

    2011-03-01

    Endemic arsenic poisoning due to long-term drinking of high arsenic groundwater has been reported in Datong Basin, northern China. To investigate the effects of microbial activities on arsenic mobilization in contaminated aquifers, Bacillus cereus ( B. cereus) isolated from high arsenic aquifer sediments of the basin was used in our microcosm experiments. The arsenic concentration in the treatment with both bacteria and sodium citrate or glucose had a rapid increase in the first 18 d, and then, it declined. Supplemented with bacteria only, the concentration could increase on the second day. By contrast, the arsenic concentration in the treatment supplemented with sodium citrate or glucose was kept very low. These results indicate that bacterial activities promoted the release of arsenic in the sediments. Bacterial activities also influenced other geochemical parameters of the aqueous phase, such as pH, Eh, and the concentrations of dissolved Fe, Mn, and Al that are important controls on arsenic release. The removal of Fe, Mn, and Al from sediment samples was observed with the presence of B. cereus. The effects of microbial activities on Fe, Mn, and Al release were nearly the same as those on As mobilization. The pH values of the treatments inoculated with bacteria were lower than those without bacteria, still at alkaline levels. With the decrease of Eh values in treatments inoculated with bacteria, the microcosms became more reducing and are thus favorable for arsenic release.

  6. Extended genetic analysis of Brazilian isolates of Bacillus cereus and Bacillus thuringiensis

    Directory of Open Access Journals (Sweden)

    Viviane Zahner

    2013-02-01

    Full Text Available Multiple locus sequence typing (MLST was undertaken to extend the genetic characterization of 29 isolates of Bacillus cereus and Bacillus thuringiensis previously characterized in terms of presence/absence of sequences encoding virulence factors and via variable number tandem repeat (VNTR. Additional analysis involved polymerase chain reaction for the presence of sequences (be, cytK, inA, pag, lef, cya and cap, encoding putative virulence factors, not investigated in the earlier study. MLST analysis ascribed novel and unique sequence types to each of the isolates. A phylogenetic tree was constructed from a single sequence of 2,838 bp of concatenated loci sequences. The strains were not monophyletic by analysis of any specific housekeeping gene or virulence characteristic. No clear association in relation to source of isolation or to genotypic profile based on the presence or absence of putative virulence genes could be identified. Comparison of VNTR profiling with MLST data suggested a correlation between these two methods of genetic analysis. In common with the majority of previous studies, MLST was unable to provide clarification of the basis for pathogenicity among members of the B. cereus complex. Nevertheless, our application of MLST served to reinforce the notion that B. cereus and B. thuringiensis should be considered as the same species.

  7. Extended genetic analysis of Brazilian isolates of Bacillus cereus and Bacillus thuringiensis

    Science.gov (United States)

    Zahner, Viviane; Silva, Ana Carolina Telles de Carvalho e; de Moraes, Gabriela Pinhel; McIntosh, Douglas; de Filippis, Ivano

    2013-01-01

    Multiple locus sequence typing (MLST) was undertaken to extend the genetic characterization of 29 isolates of Bacillus cereus and Bacillus thuringiensis previously characterized in terms of presence/absence of sequences encoding virulence factors and via variable number tandem repeat (VNTR). Additional analysis involved polymerase chain reaction for the presence of sequences (be, cytK, inA, pag, lef, cya and cap), encoding putative virulence factors, not investigated in the earlier study. MLST analysis ascribed novel and unique sequence types to each of the isolates. A phylogenetic tree was constructed from a single sequence of 2,838 bp of concatenated loci sequences. The strains were not monophyletic by analysis of any specific housekeeping gene or virulence characteristic. No clear association in relation to source of isolation or to genotypic profile based on the presence or absence of putative virulence genes could be identified. Comparison of VNTR profiling with MLST data suggested a correlation between these two methods of genetic analysis. In common with the majority of previous studies, MLST was unable to provide clarification of the basis for pathogenicity among members of the B. cereus complex. Nevertheless, our application of MLST served to reinforce the notion that B. cereus and B. thuringiensis should be considered as the same species. PMID:23440117

  8. Bacillus cereus X5 Enhanced Bio-Organic Fertilizers Effectively Control Root-Knot Nematodes (Meloidogyne sp.)

    Institute of Scientific and Technical Information of China (English)

    XIAO Tong-Jian; CHEN Fang; GAO Chao; ZHAO Qing-Yun; SHEN Qi-Rong; RAN Wei

    2013-01-01

    The efficacy of Bacillus cereus X5 as a potential biological control agent against root-knot nematodes was evaluated in vitro by examining second-stage juvenile mortality and egg hatching rate under addition of culture filtrate and in planta by application of bio-organic fertilizers enhanced with B.cereus X5,B.thuringiensis BTG,or Trichoderma harzianum SQR-T037 alone or together in greenhouse and field experiments.The biofumigation of the root-knot nematode-infested soil with organic materials (chicken manure,pig manure and rice straw) alone or in combination with B.cereus X5 was also conducted in greenhouse experiments.In laboratory,the filtrate of B.cereus X5 more effectively reduced egg hatching rates during the incubation period for 14 d and more effectively killed the second-stage juvenile during the incubation period of 24 h than that of B.thuringiensis BTG.The highest dry shoot weights for greenhouse tomatoes and field muskmelons were found in both the treatment consisting of the bio-organic fertilizer enhanced with the three biocontrol agents and the treatment consisting of the bio-organic fertilizer enhanced only with B.cereus X5.The two bio-organic fertilizers achieved better nematicidal effects than those enhanced only with B.thuringiensis BTG or T.harzianum SQR-T037.B.cereus X5 also enhanced effect of biofumigation,which resulted in increased plant biomass and reduced nematode counts in the roots and rhizosphere soil.Therefore,these results suggested that biological control of root-knot nematodes both in greenhouses and fields could be effectively achieved by using B.cereus X5 and agricultural wastes.

  9. Characterization and Exposure Assessment of Emetic Bacillus cereus and Cereulide Production in Food Products on the Dutch Market.

    Science.gov (United States)

    Biesta-Peters, Elisabeth G; Dissel, Serge; Reij, Martine W; Zwietering, Marcel H; in't Veld, Paul H

    2016-02-01

    The emetic toxin cereulide, which can be produced by Bacillus cereus, can be the cause of food poisoning upon ingestion by the consumer. The toxin causes vomiting and is mainly produced in farinaceous food products. This article includes the prevalence of B. cereus and of cereulide in food products in The Netherlands, a characterization of B. cereus isolates obtained, cereulide production conditions, and a comparison of consumer exposure estimates with those of a previous exposure assessment. Food samples (n = 1,489) were tested for the presence of B. cereus; 5.4% of the samples contained detectable levels (>10(2) CFU/g), and 0.7% contained levels above 10(5) CFU/g. Samples (n = 3,008) also were tested for the presence of cereulide. Two samples (0.067%) contained detectable levels of cereulide at 3.2 and 5.4 μg/kg of food product. Of the 481 tested isolates, 81 produced cereulide and/or contained the ces gene. None of the starch-positive and hbl-containing isolates possessed the ces gene, whereas all strains contained the nhe genes. Culture of emetic B. cereus under nonoptimal conditions revealed a delay in onset of cereulide production compared with culture under optimal conditions, and cereulide was produced in all cases when B. cereus cells had been in the stationary phase for some time. The prevalence of cereulide-contaminated food approached the prevalence of contaminated products estimated in an exposure assessment. The main food safety focus associated with this pathogen should be to prevent germination and growth of any B. cereus present in food products and thus prevent cereulide production in foods. PMID:26818983

  10. Bacillus cereus as indicator in the sterilization of residual water with high energy electrons

    International Nuclear Information System (INIS)

    One of the main causes of water pollution is the presence of microorganisms that provoke infections, moreover of chemical substances. The processes of residual water treatment finally require of the disinfection for its use or final disposition. The radiation technology for the residual water treatment by mean of electron beams is an innovator process because as well as decomposing the chemical substance or to degrade them, also it provokes a disinfection by which this is proposed as alternative for disinfection of residual water, with the purpose in reusing the water treated in the agriculture, recreation and industry among others secondary activities, solving environmental or health problems. The objective of this work is to evaluate the use of Bacillus cereus as biological indicator in the disinfection by radiation, using High Energy Electrons. To fulfil with this objective, the work was developed in three stages, the first one consisted in the acquisition, propagation and conservation of the Bacillus cereus stumps, considering Escherichia coli and Salmonella typhimurium as pathogenic germs present in residual water. Moreover, the inocule standardization and the conditions of the Electron accelerator Type Pelletron. In the second stage it was performed the irradiation of aqueous samples of the microorganisms simulating biological pollution and the application to problem samples of a treatment plant sited in the Lerma River zone of mixed residual water. And in the third stage was performed a regression analysis to the reported survival for each kind of microorganisms. The results obtained show that with the use of Electron beams was reduced 6 logarithmic units de E. coli at 129 Gy, for S. typhimurium it was reduced 8 logarithmic units at 383 Gy and the B. cereus at 511 Gy was reduced 6.8 logarithmic units. Of the problem samples irradiated at 500 Gy, the concentration of the total account diminished from 8.70 x 107 UFC/ml to 550 UFC/ml, the presence of B. Cereus

  11. Capsules, toxins and AtxA as virulence factors of emerging Bacillus cereus biovar anthracis.

    Directory of Open Access Journals (Sweden)

    Christophe Brézillon

    2015-04-01

    Full Text Available Emerging B. cereus strains that cause anthrax-like disease have been isolated in Cameroon (CA strain and Côte d'Ivoire (CI strain. These strains are unusual, because their genomic characterisation shows that they belong to the B. cereus species, although they harbour two plasmids, pBCXO1 and pBCXO2, that are highly similar to the pXO1 and pXO2 plasmids of B. anthracis that encode the toxins and the polyglutamate capsule respectively. The virulence factors implicated in the pathogenicity of these B. cereus bv anthracis strains remain to be characterised. We tested their virulence by cutaneous and intranasal delivery in mice and guinea pigs; they were as virulent as wild-type B. anthracis. Unlike as described for pXO2-cured B. anthracis, the CA strain cured of the pBCXO2 plasmid was still highly virulent, showing the existence of other virulence factors. Indeed, these strains concomitantly expressed a hyaluronic acid (HA capsule and the B. anthracis polyglutamate (PDGA capsule. The HA capsule was encoded by the hasACB operon on pBCXO1, and its expression was regulated by the global transcription regulator AtxA, which controls anthrax toxins and PDGA capsule in B. anthracis. Thus, the HA and PDGA capsules and toxins were co-regulated by AtxA. We explored the respective effect of the virulence factors on colonisation and dissemination of CA within its host by constructing bioluminescent mutants. Expression of the HA capsule by itself led to local multiplication and, during intranasal infection, to local dissemination to the adjacent brain tissue. Co-expression of either toxins or PDGA capsule with HA capsule enabled systemic dissemination, thus providing a clear evolutionary advantage. Protection against infection by B. cereus bv anthracis required the same vaccination formulation as that used against B. anthracis. Thus, these strains, at the frontier between B. anthracis and B. cereus, provide insight into how the monomorphic B. anthracis may have

  12. Assessment of CcpA-mediated catabolite control of gene expression in Bacillus cereus ATCC 14579

    Directory of Open Access Journals (Sweden)

    Buist Girbe

    2008-04-01

    Full Text Available Abstract Background The catabolite control protein CcpA is a transcriptional regulator conserved in many Gram-positives, controlling the efficiency of glucose metabolism. Here we studied the role of Bacillus cereus ATCC 14579 CcpA in regulation of metabolic pathways and expression of enterotoxin genes by comparative transcriptome analysis of the wild-type and a ccpA-deletion strain. Results Comparative analysis revealed the growth performance and glucose consumption rates to be lower in the B. cereus ATCC 14579 ccpA deletion strain than in the wild-type. In exponentially grown cells, the expression of glycolytic genes, including a non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase that mediates conversion of D-glyceraldehyde 3-phosphate to 3-phospho-D-glycerate in one single step, was down-regulated and expression of gluconeogenic genes and genes encoding the citric acid cycle was up-regulated in the B. cereus ccpA deletion strain. Furthermore, putative CRE-sites, that act as binding sites for CcpA, were identified to be present for these genes. These results indicate CcpA to be involved in the regulation of glucose metabolism, thereby optimizing the efficiency of glucose catabolism. Other genes of which the expression was affected by ccpA deletion and for which putative CRE-sites could be identified, included genes with an annotated function in the catabolism of ribose, histidine and possibly fucose/arabinose and aspartate. Notably, expression of the operons encoding non-hemolytic enterotoxin (Nhe and hemolytic enterotoxin (Hbl was affected by ccpA deletion, and putative CRE-sites were identified, which suggests catabolite repression of the enterotoxin operons to be CcpA-dependent. Conclusion The catabolite control protein CcpA in B. cereus ATCC 14579 is involved in optimizing the catabolism of glucose with concomitant repression of gluconeogenesis and alternative metabolic pathways. Furthermore, the results point to metabolic control

  13. Characterization of Exopolysaccharides Produced by Bacillus cereus and Brachybacterium sp. Isolated from Asian Sea Bass (Lates calcarifer

    Directory of Open Access Journals (Sweden)

    Mohamed Orsod

    2012-09-01

    Full Text Available Aims: EPS extracted from marine bacteria, which associated with Asian sea bass has potential antimicrobial activities.Methodology and Results: Two marine Bacteria were isolated from Asian sea bass (Lates calcarifer obtained from aquaculture farm, located at Johor bahru Malaysia. 16S rRNA analysis for bacteria identity revealed that bacteria ors1 had 99 % identity to Bacillus cereus and ors2 had 96 % identity with Brachybacterium sp. All bacteria shared many similarities and variation in terms of biochemical reactions and microscopic observation. Exopolysaccharides (EPSs were extracted and purified from bacteria as they produced mucous colonies. Average analysis of EPS components showed 50 % carbohydrates, 26 % protein and 24 % fatty acids. The FTIR analysis confirmed the functional groups of the EPS. Screening for antimicrobial activities assays using Kirby-Bauer methods against both grams positive and negative had shown presence of inhibition zones.Conclusion, significance and impact of study: This study recommends that bacteria isolated from Asian sea bass are having antimicrobial activities and could be used as a potential source for the development of marine drugs.

  14. Evaluation of the Toxicity and Toxicokinetics of Cereulide from an Emetic Bacillus cereus Strain of Milk Origin.

    Science.gov (United States)

    Cui, Yifang; Liu, Yuan; Liu, Xiaoye; Xia, Xi; Ding, Shuangyang; Zhu, Kui

    2016-01-01

    Bacillus cereus is an opportunistic foodborne agent causing food poisoning and many infectious diseases. The heat-stable emetic toxin cereulide is one of the most prevalent toxins produced by pathogenic B. cereus, resulting in symptoms such as emesis and liver failure. In the present work, the toxicity and toxicokinetics of cereulide from an emetic B. cereus isolate (CAU45) of raw milk were evaluated. The production of cereulide was tested by a cytotoxicity test and enzyme immunoassay, and confirmed by the presence of the ces (cereulide synthetase) gene and the ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. All results showed that the amount and toxicity of cereulide produced by CAU45 was 7 to 15.3 folds higher than the reference emetic B. cereus DSMZ 4312. Cereulide in plasma was collected at different time points after a single intravenous injection to evaluate its toxicokinetics in rabbits. The maximum concentration of cereulide was achieved in 2.6 ± 3.4 h after administration, with the elimination half-life of 10.8 ± 9.1 h, which expands our understanding of the toxic effects of cereulide. Together, it suggests that urgent sanitary practices are needed to eliminate emetic toxins and emetic B. cereus in raw milk. PMID:27275834

  15. Quantitative Prevalence and Toxin Gene Profile of Bacillus cereus from Ready-to-Eat Vegetables in South Korea.

    Science.gov (United States)

    Chon, Jung-Whan; Yim, Jin-Hyeok; Kim, Hong-Seok; Kim, Dong-Hyeon; Kim, Hyunsook; Oh, Deog-Hwan; Kim, Soo-Ki; Seo, Kun-Ho

    2015-09-01

    Ready-to-eat (RTE) foods such as prepared vegetables are becoming an increasingly popular food choice. Since RTE vegetables are not commonly sterilized by heat treatment, contamination with foodborne pathogens such as Bacillus cereus (B. cereus) is a major concern. The objective of this study was to assess the quantitative prevalence and toxin gene profiles of B. cereus strains isolated from RTE vegetables. We found that 70 of the 145 (48%) tested retail vegetable salad and sprout samples were positive for B. cereus. The B. cereus isolates harbored at least one enterotoxin gene. The detection rates of nheABC, hblCDA, cytK, and entFM enterotoxin genes among all isolates were 97.1%, 100%, 81.4%, and 98.6%, respectively. No strain carried the emetic toxin genes. Only 4 strains (5.7%) from the 70 isolates were psychrotrophic and were able to grow at 7°C. All of the psychrotrophic isolates possessed at least 1 enterotoxin gene. PMID:26317539

  16. Toxin profiles of Bacillus cereus occurring in high numbers in spontaneously fermented African locust beans (Parkia biglobosa)

    DEFF Research Database (Denmark)

    Thorsen, Line; Azokpota, Paulin; Hansen, Bjarne Munk; Jakobsen, Mogens

    Bacillus cereus was reported to occur in high numbers (up to 107 CFU/g) during spontaneous fermentation of three different traditional Benin condiments; afitin, iru and sonru made from African locust beans. A total of nineteen B. cereus isolates from the ferments, were examined for the presence of...

  17. Effects of potential probiotic Bacillus cereus EN25 on growth, immunity and disease resistance of juvenile sea cucumber Apostichopus japonicus.

    Science.gov (United States)

    Zhao, Yancui; Yuan, Lei; Wan, Junli; Sun, Zhenxing; Wang, Yiyan; Sun, Hushan

    2016-02-01

    This study was conducted to determine effects of potential probiotic Bacillus cereus EN25 (isolated from mud of sea cucumber culturing water bodies) on growth, immunity and disease resistance against Vibrio splendidus infection in juvenile sea cucumbers Apostichopus japonicus. Animals were respectively fed diets with B. cereus EN25 at 0 (control), 10(5), 10(7) and 10(9) CFU/g for 30 days. Results showed that dietary B. cereus EN25 had no significant effects on growth, total coelomocytes counts and acid phosphatase activity of A. japonicus (P > 0.05). Dietary EN25 at 10(7) CFU/g had significantly improved the phagocytosis, respiratory burst activity and total nitric oxide synthase activity of animals (P japonicus (P > 0.05), whereas dietary EN25 at 10(9) CFU/g had significantly decreased its activity (P japonicus. PMID:26723266

  18. Representing Others in a Public Good Game

    Directory of Open Access Journals (Sweden)

    Karen Evelyn Hauge

    2015-09-01

    Full Text Available In many important public good situations the decision-making power and authority is delegated to representatives who make binding decisions on behalf of a larger group. The purpose of this study is to compare contribution decisions made by individuals with contribution decisions made by group representatives. We present the results from a laboratory experiment that compares decisions made by individuals in inter-individual public good games with decisions made by representatives on behalf of their group in inter-group public good games. Our main finding is that contribution behavior differs between individuals and group representatives, but only for women. While men’s choices are equally self-interested as individuals and group representatives, women make less self-interested choices as group representatives.

  19. An antibiotic, heavy metal resistant and halotolerant Bacillus cereus SIU1 and its thermoalkaline protease

    Directory of Open Access Journals (Sweden)

    Vikram Surendra

    2010-07-01

    Full Text Available Abstract Background Many workers have reported halotolerant bacteria from saline conditions capable of protease production. However, antibiotic resistance and heavy metal tolerance pattern of such organisms is not documented very well. Similarly, only a few researchers have reported the pattern of pH change of fermentation medium during the course of protease production. In this study, we have isolated a halotolerant Bacillus cereus SIU1 strain from a non-saline environment and studied its antibiotic and heavy metal resistance pattern. The isolate produces a thermoalkaline protease and changes the medium pH during the course of fermentation. Thermostability of protease was also studied for 30 min. Results Seventy bacterial strains isolated from the soils of Eastern Uttar Pradesh, India were screened for protease production. All of them exhibited protease activity. However, 40% bacterial isolates were found good protease producers as observed by caseinolytic zones on milk agar plates. Among them, culture S-4 was adjudged as the best protease producer, and was identified as Bacillus cereus by morphological, biochemical and 16 S rDNA sequence analyses. The isolate was resistant to heavy metals (As2+, Pb2+, Cs1+ and antibiotics (penicillin, lincomycin, cloxacillin, pefloxacin. Its growth behavior and protease production was studied at 45°C and pH 9.0. The protease units of 88 ml-1 were noted in unoptimized modified glucose yeast extract (GYE medium during early stationary phase at 20 h incubation period. The enzyme was stable in the temperature range of 35°-55°C. Conclusions An antibiotic and heavy metal resistant, halotolerant Bacillus cereus isolate is capable of producing thermoalkaline protease, which is active and stable at pH 9.0 and 35°-55°C. This isolate may be useful in several industrial applications owing to its halotolerance and antibiotic and heavy metal resistance characteristics.

  20. Structural and catalytic properties of L-alanine dehydrogenase from Bacillus cereus.

    Science.gov (United States)

    Porumb, H; Vancea, D; Mureşan, L; Presecan, E; Lascu, I; Petrescu, I; Porumb, T; Pop, R; Bârzu, O

    1987-04-01

    Alanine dehydrogenase from Bacillus cereus, a non-allosteric enzyme composed of six identical subunits, was purified to homogeneity by chromatography on blue-Sepharose and Sepharose 6B-CL. Like other pyridine-linked dehydrogenases, alanine dehydrogenase is inhibited by Cibacron blue, competitively with respect to NADH and noncompetitively with respect to pyruvate. The enzyme was inactivated by 0.1 M glycine/HCl (pH 2) and reactivated by 0.1 M phosphate (pH 8) supplemented with NAD+ or NADH. The reactivation was characterized by sigmoidal kinetics indicating a complex mechanism involving rate-limiting folding and association steps. Cibacron blue interfered with renaturation, presumably by competition with NADH. Chromatography on Sepharose 6B-CL of the partially renatured alanine dehydrogenase led to the separation of several intermediates, but only the hexamer was characterized by enzymatic activity. By immobilization on Sepharose 4B, alanine dehydrogenase from B. cereus retained 66% of the specific activity of the soluble enzyme. After denaturation of immobilized alanine dehydrogenase with 7 M urea, 37% of the initial protein was still bound to Sepharose, indicating that on the average the hexamer was attached to the matrix via, at most, two subunits. The ability of the denatured, immobilized subunits to pick up subunits from solution shows their capacity to fold back to the native conformation after urea treatment. The formation of "hybrids" between subunits of enzyme from B. cereus and Bacillus subtilis demonstrates the close resemblance of the tertiary and quaternary structures of alanine dehydrogenases from these species. PMID:3104322

  1. Effect of combined radiation and NaOCl/ultrasonication on reduction of Bacillus cereus spores in rice

    International Nuclear Information System (INIS)

    In this study, ionizing radiation in combination with sodium hypochlorite (NaOCl) and ultrasonication (US) was examined for its effectiveness in reducing Bacillus cereus F4810/72 spores in raw rice. We also evaluated whether the combined processing would produce synergistic effects compared to the individual treatments. The concentration of the initial B. cereus spore was approximately 2.9 log10 CFU/g. After 0.1, 0.2 and 0.3 kGy irradiation treatment, spore populations were reduced by 1.3, 1.4 and 1.6 log10 CFU/g, respectively. In the case of combined gamma irradiation and NaOCl/US treatment, the reduction was higher than those of each single treatment. The combined treatment of 0.1, 0.2 and 0.3 kGy and NaOCl (600–1000 ppm)/US (5–20 min) completely destroyed the spores in raw rice while the spores were not completely destroyed in the control treatment (0 kGy). These results indicated that it could be more effective to combine NaOCl with low dose gamma irradiation than high dose (concentration) of individual disinfection treatment to destroy B. cereus spores in food such as raw rice. - Highlights: ► B. cereus spores are frequently found in raw rice. ► Following irradiation, the raw rice were treated with NaOCl and US simultaneously. ► Significantly, combined disinfection treatments destroyed B. cereus in raw rice. ► Synergistic effects against B. cereus were observed for all combined treatment. ► Combined methods could be more efficient than a single disinfection method.

  2. Isolation and Characterisation of a Reserve Protein from the Seeds of Cereus jamacaru (Cactaceae)

    OpenAIRE

    Itayguara Ribeiro da Costa; Petrônio Augusto Simão de Souza; Carlos Bloch Jr.; Romulo Marino Llamoca-Zárate; Francisco A. P. Campos

    2001-01-01

    We describe here the isolation and characterisation of a major reserve protein from the seeds of Cereus jamacaru. (Cactaceae). This protein has a molecular mass of 5319 kDa and was isolated by a combination of gel filtration chromatography and reverse phase HPLC. The amino acid composition of the protein was determined and it was shown to have similarities with the amino acid composition of several proteins from the 2S albumin storage protein family. The usefulness of this protein as a molecu...

  3. Characterization and genomic analysis of chromate resistant and reducing Bacillus cereus strain SJ1

    Directory of Open Access Journals (Sweden)

    He Minyan

    2010-08-01

    Full Text Available Abstract Background Chromium is a toxic heavy metal, which primarily exists in two inorganic forms, Cr(VI and Cr(III. Chromate [Cr(VI] is carcinogenic, mutational, and teratogenic due to its strong oxidizing nature. Biotransformation of Cr(VI to less-toxic Cr(III by chromate-resistant and reducing bacteria has offered an ecological and economical option for chromate detoxification and bioremediation. However, knowledge of the genetic determinants for chromate resistance and reduction has been limited so far. Our main aim was to investigate chromate resistance and reduction by Bacillus cereus SJ1, and to further study the underlying mechanisms at the molecular level using the obtained genome sequence. Results Bacillus cereus SJ1 isolated from chromium-contaminated wastewater of a metal electroplating factory displayed high Cr(VI resistance with a minimal inhibitory concentration (MIC of 30 mM when induced with Cr(VI. A complete bacterial reduction of 1 mM Cr(VI was achieved within 57 h. By genome sequence analysis, a putative chromate transport operon, chrIA1, and two additional chrA genes encoding putative chromate transporters that likely confer chromate resistance were identified. Furthermore, we also found an azoreductase gene azoR and four nitroreductase genes nitR possibly involved in chromate reduction. Using reverse transcription PCR (RT-PCR technology, it was shown that expression of adjacent genes chrA1 and chrI was induced in response to Cr(VI but expression of the other two chromate transporter genes chrA2 and chrA3 was constitutive. In contrast, chromate reduction was constitutive in both phenotypic and gene expression analyses. The presence of a resolvase gene upstream of chrIA1, an arsenic resistance operon and a gene encoding Tn7-like transposition proteins ABBCCCD downstream of chrIA1 in B. cereus SJ1 implied the possibility of recent horizontal gene transfer. Conclusion Our results indicate that expression of the chromate

  4. DNA as an Adhesin: Bacillus cereus Requires Extracellular DNA To Form Biofilms▿ †

    OpenAIRE

    Vilain, Sébastien; Pretorius, Jakobus M.; Theron, Jacques; Brözel, Volker S.

    2009-01-01

    The soil saprophyte Bacillus cereus forms biofilms at solid-liquid interfaces. The composition of the extracellular polymeric matrix is not known, but biofilms of other bacteria are encased in polysaccharides, protein, and also extracellular DNA (eDNA). A Tn917 screen for strains impaired in biofilm formation at a solid-liquid interface yielded several mutants. Three mutants deficient in the purine biosynthesis genes purA, purC, and purL were biofilm impaired, but they grew planktonically lik...

  5. Spontaneous Bacterial Peritonitis (SBP) caused by Bacillus Cereus in an Alcoholic Patient: Case Report and Review of Literature.

    Science.gov (United States)

    Bhattacharyya, Sayan; Ansari, Mohammad Aftab Alam; Sarfraz, Asim; Jaiswal, Nitesh; Singh, Siddharth

    2015-02-01

    Spontaneous bacterial peritonitis (SBP) is infection of peritoneal covering of the abdomen caused by bacteria, without any known etiology. Common known predisposing factors are cirrhosis of liver and old age among others. Bacillus cereus is an uncommon cause of SBP and often wrongly interpreted as a contaminant. We hereby report a case of peritonitis in chronic alcoholic, elderly male patient presenting in the outpatient department. Bacillus cereus is often regarded as contaminant but must be carefully identified and correlated clinically in case of isolation from peritoneal fluid. PMID:25859458

  6. Microbial based assay for specific detection of β-lactam group of antibiotics in milk

    OpenAIRE

    Das, Sougata; Kumar, Naresh; Vishweswaraiah, Raghu Hirikyathanahalli; Haldar, Lopamudra; Gaare, Manju; Singh, Vinai Kumar; Puniya, Anil Kumar

    2011-01-01

    The spore forming Bacillus cereus (66) was screened for the induction of β-lactamase in presence of an inducer using iodometric assay. A significant induction in marker enzyme was observed in B. cereus 66 at maximum residual limit (MRL) of penicillin, ampicillin, cloxacillin, amoxicillin, cefalexin, and cephazolin belonging to β-lactam group of antibiotics. A microbial based assay, where enzyme induction was optimized at pH 7.0, temperature 30°C, and whey powder (0.25%) after 4 h of incubatio...

  7. Bacillus cereus AR156 primes induced systemic resistance by suppressing miR825/825* and activating defense-related genes in Arabidopsis.

    Science.gov (United States)

    Niu, Dongdong; Xia, Jing; Jiang, Chunhao; Qi, Beibei; Ling, Xiaoyu; Lin, Siyuan; Zhang, Weixiong; Guo, Jianhua; Jin, Hailing; Zhao, Hongwei

    2016-04-01

    Small RNAs play an important role in plant immune responses. However, their regulatory function in induced systemic resistance (ISR) is nascent. Bacillus cereus AR156 is a plant growth-promoting rhizobacterium that induces ISR in Arabidopsis against bacterial infection. Here, by comparing small RNA profiles of Pseudomonas syringae pv. tomato (Pst) DC3000-infected Arabidopsis with and without AR156 pretreatment, we identified a group of Arabidopsis microRNAs (miRNAs) that are differentially regulated by AR156 pretreatment. miR825 and miR825* are two miRNA generated from a single miRNA gene. Northern blot analysis indicated that they were significantly downregulated in Pst DC3000-infected plants pretreated with AR156, in contrast to the plants without AR156 pretreatment. miR825 targets two ubiquitin-protein ligases, while miR825* targets toll-interleukin-like receptor (TIR)-nucleotide binding site (NBS) and leucine-rich repeat (LRR) type resistance (R) genes. The expression of these target genes negatively correlated with the expression of miR825 and miR825*. Moreover, transgenic plants showing reduced expression of miR825 and miR825* displayed enhanced resistance to Pst DC3000 infection, whereas transgenic plants overexpressing miR825 and miR825* were more susceptible. Taken together, our data indicates that Bacillus cereus AR156 pretreatment primes ISR to Pst infection by suppressing miR825 and miR825* and activating the defense related genes they targeted. PMID:26526683

  8. Communication dated 15 April 2014 received from the Resident Representative of Norway to the Agency regarding the Working Group on Best Practices for Voluntary and Confidential Government-to-Government Communications on the Transport of MOX Fuel, High Level Radioactive Waste and, as appropriate, Irradiated Nuclear Fuel by Sea

    International Nuclear Information System (INIS)

    The Director General has received a communication dated 15 April 2014 from the Resident Representative of Norway to the Agency, referring to the Report of the Working Group on Best Practices for Voluntary and Confidential Government-to-Government Communications on the Transport of MOX Fuel, High Level Radioactive Waste and, as appropriate, Irradiated Nuclear Fuel by Sea. The communication and, as requested by the Resident Representative, the Report of the Working Group are circulated herewith for information

  9. Biogenesis of antibacterial silver nanoparticles using the endophytic bacterium Bacillus cereus isolated from Garcinia xanthochymus

    Institute of Scientific and Technical Information of China (English)

    Swetha Sunkar; C Valli Nachiyar

    2012-01-01

    Objective:To synthesize the ecofriendly nanoparticles, which is viewed as an alternative to the chemical method which initiated the use of microbes like bacteria and fungi in their synthesis. Methods: The current study uses the endophytic bacterium Bacillus cereus isolated from the Garcinia xanthochymus to synthesize the silver nanoparticles (AgNPs). The AgNPs were synthesized by reduction of silver nitrate solution by the endophytic bacterium after incubation for 3-5 d at room temperature. The synthesis was initially observed by colour change from pale white to brown which was confirmed by UV-Vis spectroscopy. The AgNPs were further characterized using FTIR, SEM-EDX and TEM analyses. Results:The synthesized nanoparticles were found to be spherical with the size in the range of 20-40 nm which showed a slight aggregation. The energy-dispersive spectra of the nanoparticle dispersion confirmed the presence of elemental silver. The AgNPs were found to have antibacterial activity against a few pathogenic bacteria like Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella typhi and Klebsiella pneumoniae. Conclusions:The endophytic bacteria identified as Bacillus cereus was able to synthesize silver nanoparticles with potential antibacterial activity.

  10. Production and characterization of poly-3-hydroxybutyrate from Bacillus cereus PS 10.

    Science.gov (United States)

    Sharma, Priyanka; Bajaj, Bijender Kumar

    2015-11-01

    Usage of renewable raw materials for production of fully degradable bioplastics (bacterial poly-3-hydroxybutyrate, PHB) has gained immense research impetus considering recalcitrant nature of petroleum based plastics, dwindling fossil fuel feed stocks, and associated green house gas emissions. However, high production cost of PHB is the major bottleneck for its wide range industrial applications. In current study, Bacillus cereus PS 10, a recent isolate, efficiently utilized molasses, an abundantly available by-product from sugar industries as sole carbon source for growth and PHB production. Most influential bioprocess variables i.e. molasses, pH and NH4Cl were identified based on Plackett-Burman-designed experiments. Design of experiment approach (response surface methodology) was further employed for optimization of these bioprocess variables, and an enhanced PHB yield (57.5%) was obtained. PHB produced by Bacillus cereus PS 10 was investigated using various physico-chemical approaches viz. thermogravimetric analysis, proton and carbon NMR ((1)H and (13)C) spectroscopy, melting point, elemental analysis and polarimetry for its detail characterization, and assessment for industrial application potential. PMID:26257381

  11. Production of Bio polymer (PHB) from Whey by Local Strain of Bacillus cereus

    International Nuclear Information System (INIS)

    The local strain Bacillus cereus S3, which isolated from the soil attached to the rice root, was employed for PHB production from whey and soya extract as the main carbon and nitrogen sources. Some supplements such as (0.5 g) tryptone and (0.5 g) NaCl were added to 75 ml whey and 25 ml soya extract to optimize the PHB accumulation medium. Different parameters including; initial ph of the medium, working volume, NaCl concentration and inoculum age and size; were carried out under shaking flask conditions (150 rpm) at 30 degree C for 48 h of incubation to enhance the PHB accumulation. The maximum PHB accumulation (2.42 gl-1) was achieved at ph 6, 100 ml working volume, (0.5-2%) NaCl, at 60 h and 4 ml inoculum age and size, respectively. An experiment was conducted to investigate the effect of gamma irradiation on the activity of B. cereus S3 towards PHB accumulation. At dose level 1.5 kGy the maximum PHB accumulation obtained was 3.2 gl-1

  12. Detection of Anthrax Simulants with Microcalorimetric Spectroscopy: Bacillus subtilis and Bacillus cereus Spores

    Science.gov (United States)

    Arakawa, Edward T.; Lavrik, Nickolay V.; Datskos, Panos G.

    2003-04-01

    Recent advances in the development of ultrasensitive micromechanical thermal detectors have led to the advent of novel subfemtojoule microcalorimetric spectroscopy (CalSpec). On the basis of principles of photothermal IR spectroscopy combined with efficient thermomechanical transduction, CalSpec provides acquisition of vibrational spectra of microscopic samples and absorbates. We use CalSpec as a method of identifying nanogram quantities of biological micro-organisms. Our studies focus on Bacillus subtilis and Bacillus cereus spores as simulants for Bacillus anthracis spores. Using CalSpec, we measured IR spectra of B. subtilis and B. cereus spores present on surfaces in nanogram quantities (approximately 100 -1000 spores). The spectra acquired in the wavelength range of 690 -4000 cm-1 (2.5 -14.5 μm) contain information-rich vibrational signatures that reflect the different ratios of biochemical makeup of the micro-organisms. The distinctive features in the spectra obtained for the two types of micro-organism can be used to distinguish between the spores of the Bacillus family. As compared with conventional IR and Fourier-transform IR microscopic spectroscopy techniques, the advantages of the present technique include significantly improved sensitivity (at least a full order of magnitude), absence of expensive IR detectors, and excellent potential for miniaturization.

  13. Evaluation of the Sporicidal Activity of Ethanol Extract of Arctium lappa Root against Bacillus cereus

    Directory of Open Access Journals (Sweden)

    Vajihe Karbasizade

    2014-10-01

    Full Text Available Background: Bacillus cereus is one of the most common causes of food spoilage, keratitis, endophthalmitis, and panophthalmitis. These bacteria produce spores which are resistant to chemical and physical agents. Nowadays, the sporicidal properties of plants have been considered as alternatives to chemical sporicidal agents. Materials and Methods: In this empirical-experimental study the effect of ethanol extract of edible burdock (Arctium lappa root has been studied on Bacillus cereus spores. In this investigation, the suspensions of tested microorganisms were cultured in sporulating agar. Sporulation process was assessed by optical microscopy following the staining of spores. Then the produced spores were exposed to various concentrations (100, 150, 200, 250, 300 mg/mL of ethanol extract of edible burdock (Arctium lappa root and finally the remaining spores were counted. With increasing concentrations of ethanol extract, the number of spores declined. Results: Pearson correlation showed inverse relation between the spores count and concentration of ethanol extract of edible burdock (Arctium lappa root (r=-0.765, p<0.001. The most effective extract concentration was 300 mg /mL. Conclusion: Ethanol extract of edible burdock (Arctium lappa root, has sporicidal activity. Only, the sporicidal nature of ethanol extract has been evaluated by this study; therefore, the assessment of other extracts and essences is necessary.

  14. Pastörize Sütlerde Bacillus cereus'un Varlığı

    OpenAIRE

    Özdemir, Haydar

    2003-01-01

    Bu çalışma, Ankara'da, Haziran, Temmuz ve Ağustos aylarında satışa sunulan ve farklı 5 firmaya ait toplam 120 adet pastörize süt örneğinde B. cereus'unvarlığı ve kontaminasyon düzeyinin belirlenmesi amacıyla yapılmıştır. Analiz bulguları çerçevesinde, toplam 120 adet pastörize süt örneğinin 56'sında (%46,6) B. cereus saptanmış olup, kontaminasyon düzeyi örneklerin 9'unda (%7,5) 103 kob/ml, 28'inde (%23,3)102 kob/ml, 19'unda (%15,8) 10 kob/ml, 64'ünde (%53,3)...

  15. Antagonistics against pathogenic Bacillus cereus in milk fermentation by Lactobacillus plantarum ZDY2013 and its anti-adhesion effect on Caco-2 cells against pathogens.

    Science.gov (United States)

    Zhang, Zhihong; Tao, Xueying; Shah, Nagendra P; Wei, Hua

    2016-04-01

    Lactobacillus plantarum ZDY2013 is a potential probiotic isolated from fermented bean acid. In this study, we aimed to evaluate the in vitro antimicrobial activity of this organism against Bacillus cereus in milk fermentation, the antiadhesion ability on intestinal epithelial cells, as well as its ability to abrogate the cytotoxic effect and expression levels of genes. We found no antimicrobial activity produced by L. plantarum once the pH was adjusted to 6.0 and 7.0. The pH decreased continuously when L. plantarum and B. cereus were co-incubated during milk fermentation, which caused a decrease in the B. cereus counts. Antiadhesion assays showed that L. plantarum can significantly inhibit the adhesion of enterotoxin-producing B. cereus ATCC14579 and pathogenic B. cereus HN001 by inhibition, competition, and displacement. The supernatants of B. cereus, either alone or in conjunction with L. plantarum, caused damage to the membrane integrity of Caco-2 cells to release lactate dehydrogenase. In addition, L. plantarum tended to attenuate proinflammatory cytokine and oxidative stress gene expression on Caco-2 cells, inducing with B. cereus HN001 supernatants. This study provided systematic insights into the antagonistic effect of L. plantarum ZDY2013, and the information may be helpful to explore potential control measures for preventing food poisoning by lactic acid bacteria. PMID:26830743

  16. Quantitative analysis of population heterogeneity of the adaptive salt stress response and growth capacity of Bacillus cereus ATCC 14579

    NARCIS (Netherlands)

    Besten, den H.M.W.; Ingham, C.J.; Hylckama Vlieg, van J.E.T.; Beerthuyzen, M.M.; Zwietering, M.H.; Abee, T.

    2007-01-01

    Bacterial populations can display heterogeneity with respect to both the adaptive stress response and growth capacity of individual cells. The growth dynamics of Bacillus cereus ATCC 14579 during mild and severe salt stress exposure were investigated for the population as a whole in liquid culture.

  17. Aislamiento e identificación de Bacillus cereus a partir de dos variantes de arroz comercial (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Irasema Pérez-Portuondo

    2011-01-01

    Full Text Available Bacillus cereus es una bacteria habitante común del suelo, de importancia tanto para la salud pública como para la Biotecnología. Con el objetivo de aislar ejemplares de esta bacteria para su utilización en estudios posteriores, así como de evaluar su permanencia en el arroz cocido, se desarrolló el protocolo propuesto por Kramer y cols. (1982. Con este fin, se tomaron muestras de arroz en grano con cáscara y de arroz cocido y se buscaron bacterias con propiedades hemolíticas y lecitinasa positiva. La identificación de los aislados se realizó mediante pruebas morfológicas y bioquímicas. Se obtuvieron 14 aislados, ocho de los cuales reunían las características distintivas de B. cereus, comparados con B. cereus ATCC 11778, incluida la resistencia a antibióticos. No se observó presencia de cuerpos parasporales típica de B. thuringiensis. Se comprobó que en el arroz cocido, transcurridas ocho horas de la cocción, pueden aislarse bacterias hemolíticas y lecitinasa positivas, en mayor número si este es conservado a temperatura ambiente, lo que convierte este alimento en potencialmente peligroso para su consumo. Estos resultados sugieren también la posibilidad de emplear al arroz como fuente para aislamiento de B. cereus.

  18. A probability model for enterotoxin production of Bacillus cereus as a function of pH and temperature

    Science.gov (United States)

    Bacillus cereus is frequently isolated from a variety of foods including vegetables, dairy products, meat, and other raw and processed foods. The bacterium is capable of producing enterotoxin and emetic toxin that can cause severe nausea, vomiting and diarrhea. The objectives of this study were to a...

  19. Bacillus cereus AR156-induced resistance to Colletotrichum acutatum is associated with priming of defense responses in loquat fruit.

    Directory of Open Access Journals (Sweden)

    Xiaoli Wang

    Full Text Available The effectiveness of a biocontrol agent Bacillus cereus AR156 for control of anthracnose rot caused by Colletotrichum acutatum in harvested loquat fruit and the possible mechanisms of its action have been investigated. Treatment of fruit with B. cereus AR156 resulted in lower disease incidence and smaller lesion diameters compared with that of untreated fruit. The treatment enhanced activities of defense-related enzymes including chitinase, β-1, 3-glucanase, phenylalanine ammonia-lyase, peroxidase and polyphenoloxidase, and promoted accumulation of H2O2. Total phenolic content and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity were also increased by treatment. Transcripts of three defense-related genes were enhanced only in fruit undergoing both B. cereus AR156 treatment and C. acutatum inoculation compared with those receiving either intervention alone. These results suggest that the disease resistance against C. acutatum in loquat fruit is enhanced by B. cereus AR156 and that the induced resistance is associated with induction and priming of defense responses in the fruit.

  20. Bacillus cereus AR156-induced resistance to Colletotrichum acutatum is associated with priming of defense responses in loquat fruit.

    Science.gov (United States)

    Wang, Xiaoli; Wang, Lei; Wang, Jing; Jin, Peng; Liu, Hongxia; Zheng, Yonghua

    2014-01-01

    The effectiveness of a biocontrol agent Bacillus cereus AR156 for control of anthracnose rot caused by Colletotrichum acutatum in harvested loquat fruit and the possible mechanisms of its action have been investigated. Treatment of fruit with B. cereus AR156 resulted in lower disease incidence and smaller lesion diameters compared with that of untreated fruit. The treatment enhanced activities of defense-related enzymes including chitinase, β-1, 3-glucanase, phenylalanine ammonia-lyase, peroxidase and polyphenoloxidase, and promoted accumulation of H2O2. Total phenolic content and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity were also increased by treatment. Transcripts of three defense-related genes were enhanced only in fruit undergoing both B. cereus AR156 treatment and C. acutatum inoculation compared with those receiving either intervention alone. These results suggest that the disease resistance against C. acutatum in loquat fruit is enhanced by B. cereus AR156 and that the induced resistance is associated with induction and priming of defense responses in the fruit. PMID:25386680

  1. Enhanced transformation efficiency of recalcitrant Bacillus cereus and Bacillus weihenstephanensis isolates upon in vitro methylation of plasmid DNA

    NARCIS (Netherlands)

    Nierop Groot, M.N.; Nieboer, F.; Abee, T.

    2008-01-01

    Digestion patterns of chromosomal DNAs of Bacillus cereus and Bacillus weihenstephanensis strains suggest that Sau3AI-type restriction modification systems are widely present among the isolates tested. In vitro methylation of plasmid DNA was used to enhance poor plasmid transfer upon electroporation

  2. Recipes for Antimicrobial Wine Marinades against Bacillus cereus, Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella enterica

    Science.gov (United States)

    We evaluated bactericidal activities of several antimicrobial wine recipes consisting of red and white wine extracts of oregano leaves with added garlic juice and oregano oil against Bacillus cereus, Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella enterica. Dose-response plots were...

  3. Direct-Imaging-Based Quantification of Bacillus cereus ATCC 14579 Population Heterogeneity at a Low Incubation Temperature▿

    OpenAIRE

    Besten, den, H.; Garcia, D.; Moezelaar, R.; Zwietering, M.H.; Abee, T.

    2009-01-01

    Bacillus cereus ATCC 14579 was cultured in microcolonies on Anopore strips near its minimum growth temperature to directly image and quantify its population heterogeneity at an abusive refrigeration temperature. Eleven percent of the microcolonies failed to grow during low-temperature incubation, and this cold-induced population heterogeneity could be partly attributed to the loss of membrane integrity of individual cells.

  4. Draft Genome Sequences of Supercritical CO[subscript 2]-Tolerant Bacteria Bacillus subterraneus MITOT1 and Bacillus cereus MIT0214

    OpenAIRE

    Peet, Kyle C.; Thompson, Janelle R.

    2015-01-01

    We report draft genome sequences of Bacillus subterraneus MITOT1 and Bacillus cereus MIT0214 isolated through enrichment of samples from geologic sequestration sites in pressurized bioreactors containing a supercritical (sc) CO[subscript 2] headspace. Their genome sequences expand the phylogenetic range of sequenced bacilli and allow characterization of molecular mechanisms of scCO[subscript 2] tolerance.

  5. Enhanced transformation efficiency of recalcitrant Bacillus cereus and Bacillus weihenstephanensis isolates upon in vitro methylation of plasmid DNA

    OpenAIRE

    Nierop Groot, M.N.; Nieboer, F.; Abee, T.

    2008-01-01

    Digestion patterns of chromosomal DNAs of Bacillus cereus and Bacillus weihenstephanensis strains suggest that Sau3AI-type restriction modification systems are widely present among the isolates tested. In vitro methylation of plasmid DNA was used to enhance poor plasmid transfer upon electroporation to recalcitrant strains that carry Sau3AI restriction barriers.

  6. Detection of viable enterotoxin-producing Bacillus cereus and analysis of toxigenicity from ready-to-eat foods and infant formula milk powder by multiplex PCR.

    Science.gov (United States)

    Zhang, Zhihong; Feng, Lixia; Xu, Hengyi; Liu, Chengwei; Shah, Nagendra P; Wei, Hua

    2016-02-01

    Bacillus cereus is responsible for several outbreaks of foodborne diseases due to its emetic toxin and enterotoxin. Enterotoxins, cytotoxin K (CytK), nonhemolytic enterotoxin (Nhe), and hemolysin BL (Hbl), have been recorded in several diarrheal cases due to food poisoning from B. cereus. The objective of this study was to develop a rapid and accurate method that combines multiplex PCR with propidium monoazide to selectively detect viable cells of enterotoxin-producing B. cereus in milk powder, noodles, and rice, and investigate the distribution of enterotoxins in 62 strains of B. cereus in Jiangxi province, China. The specificity of primers of 3 enterotoxins (i.e., cytK, nheA, and hblD) of B. cereus was verified by inclusivity and exclusivity tests using single PCR. Upon optimization of multiplex PCR conditions, it was found that the detection limit of viable cells was 10(2) cfu/mL of B. cereus in pure culture. By enrichment for 3 or 4 h and propidium monoazide pretreatment, a protocol for detection of viable cells as low as 2.2×10(1) cfu/g in spiked food (e.g., milk powder, noodles, and rice) was established and proved valid even under the interference of non-Bacillus cereus at as high as 10(5) cfu/g. Moreover, the protocol based on multiplex PCR for detection was applied for the analysis of distribution of toxin gene of B. cereus, and the results showed a regional feature for toxin gene distribution, indicating that potential toxigenicity of B. cereus should be evaluated further. PMID:26686715

  7. Toxin profiles of Bacillus cereus occurring in high numbers in spontaneously fermented African locust beans (Parkia biglobosa)

    DEFF Research Database (Denmark)

    Thorsen, Line; Azokpota, Paulin; Hansen, Bjarne Munk; Jakobsen, Mogens

    The microbiology of the naturally fermented African condiments Afiitin, iru and sonru produced in Benin from locust beans, has recently been studied showing high Bacillus cereus counts of log7CFU/g (Azokpota, 2005). A total of 19 B. cereus strains isolated from the three condiments showed to be...... potentially pathogenic by harboring and expressing enterotoxin and emetic genes. Isolates from afiitin were the most cytotoxic as detected by a Vero-cell assay, while an isolate from sonru was a potent cereulide producer. Interestingly B. cereus food poisoning frm the consumption of the fermented condiments...

  8. Effect of glass filtered solar radiation and of 2,4 dinitrophenol on growth of Bacillus cereus and on its survival after far-UV irradiation

    International Nuclear Information System (INIS)

    Effect of 2,4 dinitrophenol (DNP) and of glass filtered solar radiation (GFSR) on growth of B. cereus is similative. Far-UV radiation induce killing in cell suspension of B. cereus. Pretreatment with GFSR and post-treatment with DNP increases the survival of B. cereus irradiated with far-UV. The increase in survival is proportional to the period of growth delay. However, 60 min pretreatment with GFSR causes increase in survival maximally. It is postulated that GFSR impairs the oxidative metabolism of cell by destroying a protein involved in this process. (auth.)

  9. Fabrication of an electrochemical DNA-based biosensor for Bacillus cereus detection in milk and infant formula.

    Science.gov (United States)

    Izadi, Zahra; Sheikh-Zeinoddin, Mahmoud; Ensafi, Ali A; Soleimanian-Zad, Sabihe

    2016-06-15

    This paper describes fabrication of a DNA-based Au-nanoparticle modified pencil graphite electrode (PGE) biosensor for detection of Bacillus cereus, causative agent of two types of food-borne disease, i.e., emetic and diarrheal syndrome. The sensing element of the biosensor was comprised of gold nanoparticles (GNPs) self-assembled with single-stranded DNA (ssDNA) of nheA gene immobilized with thiol linker on the GNPs modified PGE. The size, shape and dispersion of the GNPs were characterized by field emission scanning electron microscope (FESEM). Detection of B. cereus was carried out based on an increase in the charge transfer resistance (Rct) of the biosensor due to hybridization of the ss-DNA with target DNA. An Atomic force microscope (AFM) was used to confirm the hybridization. The biosensor sensitivity in pure cultures of B. cereus was found to be 10(0) colony forming units per milliliter (CFU/mL) with a detection limit of 9.4×10(-12)molL(-1). The biosensor could distinguish complementary from mismatch DNA sequence. The proposed biosensor exhibited a rapid detection, low cost, high sensitivity to bacterial contamination and could exclusively and specifically detect the target DNA sequence of B. cereus from other bacteria that can be found in dairy products. Moreover, the DNA biosensor exhibited high reproducibility and stability, thus it may be used as a suitable biosensor to detect B. cereus and to become a portable system for food quality control. PMID:26896793

  10. Cloning and expression of vgb gene in Bacillus cereus, improve phenol and p-nitrophenol biodegradation

    Science.gov (United States)

    Vélez-Lee, Angel Eduardo; Cordova-Lozano, Felipe; Bandala, Erick R.; Sanchez-Salas, Jose Luis

    2016-02-01

    In this work, the vgb gene from Vitrocilla stercoraria was used to genetically modify a Bacillus cereus strain isolated from pulp and paper wastewater effluent. The gene was cloned in a multicopy plasmid (pUB110) or uni-copy gene using a chromosome integrative vector (pTrpBG1). B. cereus and its recombinant strains were used for phenol and p-nitrophenol biodegradation using aerobic or micro-aerobic conditions and two different temperatures (i.e. 37 and 25 °C). Complete (100%) phenol degradation was obtained for the strain where the multicopy of vgb gene was present, 98% for the strain where uni-copy gene was present and 45% for wild type strain for the same experimental conditions (i.e. 37 °C and aerobic condition). For p-nitrophenol degradation at the same conditions, the strain with the multi-copy vgb gene was capable to achieve 50% of biodegradation, ∼100% biodegradation was obtained using the uni-copy strain and ∼24% for wild type strain. When the micro-aerobic condition was tested, the biodegradation yield showed a significant decreased. The biodegradation trend observed for aerobic was similar for micro-aerobic assessments: the modified strains showed higher degradation rates when compared with wild type strain. For all experimental conditions, the highest p-nitrophenol degradation was observed using the strain with uni-copy of vgb gene. Besides the increase of biodegradative capability of the strain, insertion of the vgb gene was observed able to modify other morphological characteristics such as avoiding the typical flake formation in the B. cereus culture. In both cases, the modification seems to be related with the enhancement of oxygen supply to the cells generated by the vgb gene insertion. The application of the genetically modified microorganism (GMM) to the biodegradation of pollutants in contaminated water possesses high potential as an environmentally friendly technology to facing this emergent problem.

  11. Transcriptional responses of Bacillus cereus towards challenges with the polysaccharide chitosan.

    Directory of Open Access Journals (Sweden)

    Hilde Mellegård

    Full Text Available The antibacterial activity of the polysaccharide chitosan towards different bacterial species has been extensively documented. The response mechanisms of bacteria exposed to this biopolymer and the exact molecular mechanism of action, however, have hardly been investigated. This paper reports the transcriptome profiling using DNA microarrays of the type-strain of Bacillus cereus (ATCC 14579 exposed to subinhibitory concentrations of two water-soluble chitosan preparations with defined chemical characteristics (molecular weight and degree of acetylation (F(A. The expression of 104 genes was significantly altered upon chitosan A (weight average molecular weight (M(w 36.0 kDa, F(A = 0.01 exposure and 55 genes when treated with chitosan B (M(w 28.4 kDa, F(A = 0.16. Several of these genes are involved in ion transport, especially potassium influx (BC0753-BC0756. Upregulation of a potassium transporting system coincides with previous studies showing a permeabilizing effect on bacterial cells of this polymer with subsequent loss of potassium. Quantitative PCR confirmed the upregulation of the BC0753 gene encoding the K(+-transporting ATPase subunit A. A markerless gene replacement method was used to construct a mutant strain deficient of genes encoding an ATP-driven K(+ transport system (Kdp and the KdpD sensor protein. Growth of this mutant strain in potassium limiting conditions and under salt stress did not affect the growth pattern or growth yield compared to the wild-type strain. The necessity of the Kdp system for potassium acquisition in B. cereus is therefore questionable. Genes involved in the metabolism of arginine, proline and other cellular constituents, in addition to genes involved in the gluconeogenesis, were also significantly affected. BC2798 encoding a chitin binding protein was significantly downregulated due to chitosan exposure. This study provides insight into the response mechanisms of B. cereus to chitosan treatment and

  12. Transcriptional responses of Bacillus cereus towards challenges with the polysaccharide chitosan.

    Science.gov (United States)

    Mellegård, Hilde; Kovács, Ákos T; Lindbäck, Toril; Christensen, Bjørn E; Kuipers, Oscar P; Granum, Per E

    2011-01-01

    The antibacterial activity of the polysaccharide chitosan towards different bacterial species has been extensively documented. The response mechanisms of bacteria exposed to this biopolymer and the exact molecular mechanism of action, however, have hardly been investigated. This paper reports the transcriptome profiling using DNA microarrays of the type-strain of Bacillus cereus (ATCC 14579) exposed to subinhibitory concentrations of two water-soluble chitosan preparations with defined chemical characteristics (molecular weight and degree of acetylation (F(A))). The expression of 104 genes was significantly altered upon chitosan A (weight average molecular weight (M(w)) 36.0 kDa, F(A) = 0.01) exposure and 55 genes when treated with chitosan B (M(w) 28.4 kDa, F(A) = 0.16). Several of these genes are involved in ion transport, especially potassium influx (BC0753-BC0756). Upregulation of a potassium transporting system coincides with previous studies showing a permeabilizing effect on bacterial cells of this polymer with subsequent loss of potassium. Quantitative PCR confirmed the upregulation of the BC0753 gene encoding the K(+)-transporting ATPase subunit A. A markerless gene replacement method was used to construct a mutant strain deficient of genes encoding an ATP-driven K(+) transport system (Kdp) and the KdpD sensor protein. Growth of this mutant strain in potassium limiting conditions and under salt stress did not affect the growth pattern or growth yield compared to the wild-type strain. The necessity of the Kdp system for potassium acquisition in B. cereus is therefore questionable. Genes involved in the metabolism of arginine, proline and other cellular constituents, in addition to genes involved in the gluconeogenesis, were also significantly affected. BC2798 encoding a chitin binding protein was significantly downregulated due to chitosan exposure. This study provides insight into the response mechanisms of B. cereus to chitosan treatment and the

  13. Effects of Aronia melanocarpa Constituents on Biofilm Formation of Escherichia coli and Bacillus cereus

    Directory of Open Access Journals (Sweden)

    Marie Bräunlich

    2013-12-01

    Full Text Available Many bacteria growing on surfaces form biofilms. Adaptive and genetic changes of the microorganisms in this structure make them resistant to antimicrobial agents. Biofilm-forming organisms on medical devices can pose serious threats to human health. Thus, there is a need for novel prevention and treatment strategies. This study aimed to evaluate the ability of Aronia melanocarpa extracts, subfractions and compounds to prevent biofilm formation and to inhibit bacterial growth of Escherichia coli and Bacillus cereus in vitro. It was found that several aronia substances possessed anti-biofilm activity, however, they were not toxic to the species screened. This non-toxic inhibition may confer a lower potential for resistance development compared to conventional antimicrobials.

  14. Growth of Bacillus cereus on solid media as affected by agar, sodium chloride, and potassium sorbate.

    Science.gov (United States)

    Stecchini, M L; Del Torre, M; Donda, S; Maltini, E

    2000-07-01

    The effect of two independent variables: microstructure, as modified by the agar content (1.0, 4.0, 7.0%), and water activity (a(w)), as modified by the NaCl content (0.5, 2.5, 4.5%), in the absence or in the presence of potassium sorbate (0.0; 2,000 ppm) on Bacillus cereus growth on solid media was studied. The time to visible growth (TVG) and the radial growth rate (RGR) of colonies were evaluated. TVG was not affected by microstructure and K-sorbate, although when a(w) was reduced, TVG tended to increase. RGR depended on linear effects of microstructure and a(w) variables and their interaction. When K-sorbate was added to cultural media, RGR was reduced significantly. However, in the presence of K-sorbate, RGR was found to change only when a(w) vas varied. PMID:10914662

  15. A Pseudo-tRNA Modulates Antibiotic Resistance in Bacillus cereus

    DEFF Research Database (Denmark)

    Rogers, Theresa E; Ataide, Sandro F; Dare, Kiley;

    2012-01-01

    Bacterial genomic islands are often flanked by tRNA genes, which act as sites for the integration of foreign DNA into the host chromosome. For example, Bacillus cereus ATCC14579 contains a pathogenicity island flanked by a predicted pseudo-tRNA, tRNA(Other), which does not function in translation...... regulatory RNA. These findings illustrate that while integration of genomic islands often leaves tRNA genes intact and functional, in other instances inactivation may generate tRNA-like elements that are then recruited to other functions in the cell........ Deletion of tRNA(Other) led to significant changes in cell wall morphology and antibiotic resistance and was accompanied by changes in the expression of numerous genes involved in oxidative stress responses, several of which contain significant complementarities to sequences surrounding tRNA(Other). This...

  16. Direct recovery of cyclodextringlycosyltransferase from Bacillus cereus using aqueous two-phase flotation.

    Science.gov (United States)

    Lin, Yu Kiat; Show, Pau Loke; Yap, Yee Jiun; Tan, Chin Ping; Ng, Eng-Poh; Ariff, Arbakariya B; Mohamad Annuar, Mohamad Suffian B; Ling, Tau Chuan

    2015-12-01

    Purification of cyclodextrin glycosyl transferase (CGTase) from Bacillus cereus using polyethylene glycol (PEG)-potassium phosphates aqueous two-phase flotation (ATPF) system was studied in this paper. The effects of varying PEG molecular weight, tie-line length (TLL) value, volume ratio (VR), pH value, crude concentration and gas nitrogen flotation time were investigated. The optimal condition for purification of CGTase was attained at 18.0% (w/w) PEG 8000, 7.0% (w/w) potassium phosphates, VR of 3.0, 20% (w/w) crude load at pH 7, and 80 min nitrogen flotation time at a flow rate of 5 L/min. With this optimal condition, purification factor (PFT) of 21.8 and a yield (YT) of 97.1% were attained. CGTase was successfully purified in a single downstream processing step using the ATPF. PMID:26111602

  17. Crystallization and preliminary X-ray analysis of a phosphopentomutase from Bacillus cereus

    Energy Technology Data Exchange (ETDEWEB)

    Panosian, Timothy D.; Nannemann, David P.; Bachmann, Brian O.; Iverson, T.M. (Vanderbilt)

    2013-09-18

    Phosphopentomutases (PPMs) interconvert D-ribose 5-phosphate and {alpha}-D-ribose 1-phosphate to link glucose and nucleotide metabolism. PPM from Bacillus cereus was overexpressed in Escherichia coli, purified to homogeneity and crystallized. Bacterial PPMs are predicted to contain a di-metal reaction center, but the catalytically relevant metal has not previously been identified. Sparse-matrix crystallization screening was performed in the presence or absence of 50 mM MnCl{sub 2}. This strategy resulted in the formation of two crystal forms from two chemically distinct conditions. The crystals that formed with 50 mM MnCl{sub 2} were more easily manipulated and diffracted to higher resolution. These results suggest that even if the catalytically relevant metal is not known, the crystallization of putative metalloproteins may still benefit from supplementation of the crystallization screens with potential catalytic metals.

  18. Optimization of Pulsed-field Gel Electrophoresis Procedure for Bacillus cereus.

    Science.gov (United States)

    Zhang, Hui Juan; Pan, Zhuo; Wei, Jian Chun; Zhang, En Min; Cai, Hong; Liang, Xu Dong; Li, Wei

    2016-03-01

    In order to develop a rapid and reliable method for B. cereus genotyping, factors influencing PFGE results, including preparation of bacterial cells embedded in agarose, lysis of embedded cells, enzymatic digestion of intact genomic DNA, and electrophoresis parameters allowing for reproducible and meaningful DNA fragment separation, were controlled. Optimal cellular growth (Luria-Bertani agar plates for 12-18 h) and lysis conditions (4 h incubation with 500 µg/mL lysozyme) produced sharp bands on the gel. Restriction enzyme NotI was chosen as the most suitable. Twenty-two isolates were analyzed by NotI digestion, using three electrophoretic parameters (EPs). The EP-a was optimal for distinguishing between isolates. The optimized protocol could be completed within 40 h which is a significant improvement over the previous methods. PMID:27109136

  19. Characterization of melanin produced by a wild-type strain of Bacillus cereus

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jianping; CAI Jun; DENG Yinyue; CHEN Yuehua; REN Gaixin

    2007-01-01

    Bacillus cereus 58 (Bc58)is a UV-resistant wild type strain that has an ability to produce a sorrel pigment induced by L-tyrosine.The Fourier-transform infrared (FT-IR)spectra and chemical tests of its pigment are similar to that of the standard melanin (Sigma).A bioassay shows that the LC50 of a Bacillus thuringiensis (Bt)formulation added with the melanin of Bc58 and exposed to UV for 5 h is 16.1 μg/ml,which is similar to that of the Bt formulation without UV treatment,however,it is almost double that of the Bt formulation exposed to UV without the melanin of Bc58.The result of SDS-PAGE indicates that the melanin of Bc58 can protect the insecticidal crystal proteins from degradation.This suggests that it is an excellent UV protective agent for the insecticidal crystal proteins of the Bt formulation.

  20. Delay in growth induced by glass filtered solar radiation in Bacillus cereus

    International Nuclear Information System (INIS)

    Growth delay caused by glass-filtered solar radiation in B. Cereus depends on the time of exposure and age of the culture. However this radiation does not bring about total destruction of bacterial cells. The injurious effect is annulled and normal growth pattern is restored after certain hours in the growth medium. Amino acids present in the medium, are essential for recovery. Inclusion of chloramphenicol in the medium does not bring about restitution of growth of the irradiated cells. Thus it can be presumed that some chloramphenical susceptible protein(s) is damaged due to glass-filtered solar-radiation and the interval observed between irradiation and restoration is in all probability, utilized by the bacterial cells in the resynthesis or repair of the damaged protein. (author)

  1. Mutation effect of MeV protons on bioflocculant bacteria Bacillus cereus

    International Nuclear Information System (INIS)

    A 3.2 MeV proton beam was used to irradiate bioflocculant bacteria (Bacillus cereus) to achieve mutation. The ion fluence ranged from 1011 to 1014/cm2. Most of the bacteria were killed when the ion fluence reached 1012 ions/cm2. The survival ratio drops in an exponential way on further increasing the ion fluence. The flocculating activity of 7 samples out of 51 showed a positive change, and a perfect mutant C7-23 with a stable high capacity of bioflocculant production was found. RAPD measurements showed that a new lane appears in this sample. The flocculating activity of the C7-23 bacteria increased by factors of 22%, 54% and 217% under pH values of 4, 7 or 10, respectively

  2. Structural basis of the phospholipase C activity in neutral sphingomyelinase from Bacillus cereus

    International Nuclear Information System (INIS)

    Degradation of cell membrane and mucosa, of which phospholipids are major components, and production of lipid mediators are roles of phospholipases from pathogenic bacteria to grow, survive and spread in the host organism. The studies on the enzymes the important for the pathobiology of bacterial infectious disease. The crystal structure of Sphingomyelinase from Bacillus cereus revealed the structure basis of the phospholipase C and hemolysis activities in a divalent cation dependent manner. The water-bridged double divalent cations were concluded to be the catalytic architecture to the phospholipase C activity. In addition, the β-hairpin structure with aromatic amino acid residues was shown to be involved in the membrane binding of the enzyme as a part of the hemolysis activity. (author)

  3. Influence of heat and radiation on the germinability and viability of B. cereus BIS-59 spores

    International Nuclear Information System (INIS)

    Spores of Bicillus cereus BIS-59, isolated in this laboratory from shrimps, exhibited an exponential gamma radiation survival curve with a d10 value of 400 krad as compared with a D10 value of 30 krad for the vegetative cells. The D10 value of DPA-depleted spores was also 400 krad indicating that DPA does not influence the radiation response of these spores. Maximum germination monitored with irradiated spores was 60 percent as compared with 80 percent in case of unirradiated spores. Radiation-induced inhibition of the germination processes was not dose dependent. Heat treatment (15 min at 80 C) to spores resulted in activation of the germination process; however, increase in heating time (30 min and 60 min) increased the germination lag period. DPA-depleted spores were less heat resistant than normal spores and exhibited biphasic exponential inactivation. (author)

  4. Mutation effect of MeV protons on bioflocculant bacteria Bacillus cereus

    Science.gov (United States)

    Yang, Y. N.; Ren, N.; Xue, J. M.; Yang, J.; Rong, B. L.

    2007-09-01

    A 3.2 MeV proton beam was used to irradiate bioflocculant bacteria (Bacillus cereus) to achieve mutation. The ion fluence ranged from 1011 to 1014/cm2. Most of the bacteria were killed when the ion fluence reached 1012 ions/cm2. The survival ratio drops in an exponential way on further increasing the ion fluence. The flocculating activity of 7 samples out of 51 showed a positive change, and a perfect mutant C7-23 with a stable high capacity of bioflocculant production was found. RAPD measurements showed that a new lane appears in this sample. The flocculating activity of the C7-23 bacteria increased by factors of 22%, 54% and 217% under pH values of 4, 7 or 10, respectively.

  5. Efecto Antagónico del Kefir sobre Endosporas y Células Vegetativas de Bacillus Cereus y Clostridium Perfringens Antagonistic Effect of the Kefir on Endospores and Vegetative Cells of Bacillus Cereus and Clostridium Perfringens

    Directory of Open Access Journals (Sweden)

    Ricardo J Anselmo

    2010-01-01

    Full Text Available Se estudió el efecto bactericida del kéfir sobre endosporas y células vegetativas de Bacillus cereus y Clostridium perfringens inoculados en kéfir durante su almacenamiento. Muestras de kéfir de dos procedencias, uno de origen italiano y otro peruano, fueron inoculadas con una población conocida de B. cereus y Cl. perfringens (10(6 UFC/mL y conservados a 4ºC durante 30 días. Cada dos días se realizó un recuento de bacterias lácticas, de levaduras, de los patógenos agregados y se determinó el pH. La población de células vegetativas de B. cereus se redujo a niveles no detectables en 14 días de almacenamiento y la de sus endosporas en 20 días de almacenamiento. Respecto a Cl. perfringens se redujo la población de células vegetativas y de endosporas a niveles no detectables en 14 y 18 días de almacenamiento, respectivamente. Los resultados confirman los efectos bactericidas de los cultivos iniciadores del kéfir.The bactericide effect of the kefir was studied on endospores and vegetative cells of Bacillus cereus and Clostridium perfringens inoculated in kefir during its storage. Samples of kefir of two different origins, one Italian and the other Peruvian were inoculated with a well-known population of B. cereus and Cl. perfringens (10(6 UFC/mL and conserved at 4ºC during 30 days. Every two days it was carried out a recount of lactic bacteria, of yeasts, of the pathogenic added and the pH was determined. The population of vegetative cells of B. cereus reduced to non detectable levels in 14 days of storage and of its endospores in 20 days of storage. Regarding Cl. perfringens the population of vegetative cells and its endospores reduced to non detectable levels in 14 and 18 days of storage, respectively. The results confirm the bactericide effects of the starter cultures of kefir.

  6. The representative animal

    OpenAIRE

    Harrison, J. M.

    1994-01-01

    The anthropocentric approach to the study of animal behavior uses representative nonhuman animals to understand human behavior. This approach raises problems concerning the comparison of the behavior of two different species. The datum of behavior analysis is the behavior of humans and representative animal phenotypes. The behavioral phenotype is the product of the ontogeny and phylogeny of each species, and this requires that contributions of genotype as well as behavioral history to experim...

  7. Identification and Characterization of Bacillus cereus SW7-1 in Bombyx mori (Lepidoptera: Bombycidae).

    Science.gov (United States)

    Li, Guan-Nan; Xia, Xue-Juan; Zhao, Huan-Huan; Sendegeya, Parfait; Zhu, Yong

    2015-01-01

    The bacterial diseases of silkworms cause significant reductions in sericulture and result in huge economic loss. This study aimed to identify and characterize a pathogen from diseased silkworm. SW7-1, a pathogenic bacterial strain, was isolated from the diseased silkworm. The strain was identified on the basis of its bacteriological properties and 16S rRNA gene sequence. The colony was round, slightly convex, opaque, dry, and milky on a nutrient agar medium, the colony also exhibited jagged edges. SW7-1 was Gram-positive, without parasporal crystal, and 0.8-1.2 by 2.6-3.4 µm in length, resembling long rods with rounded ends. The strain was positive to most of the physiological biochemical tests used in this study. The strain could utilize glucose, sucrose, and maltose. The results of its 16S rRNA gene sequence analysis revealed that SW7-1 shared the highest sequence identity (>99%) with Bacillus cereus strain 14. The bacterial strain was highly susceptible to gentamycin, streptomycin, erythromycin, norfloxacin, and ofloxacin and moderately susceptible to tetracycline and rifampicin. It exhibited resistance to other antibiotics. SW7-1 had hemolytic activity and could produce extracellular casease, lipase, and amylase. SW7-1 could reproduce septicemia-like symptoms with high mortality rate when re-fed to healthy silkworm. .The median lethal concentration (LC50) was 5.45 × 10(4) cfu/ml. Thus, SW7-1 was identified as B. cereus, which is a pathogen for silkworm and human infections are possible. PMID:26411789

  8. Isolation and characterization of a furfural-degrading bacterium Bacillus cereus sp. strain DS1.

    Science.gov (United States)

    Zheng, Dan; Bao, Jianguo; Lu, Jueming; Gao, Chunlei

    2015-02-01

    Furfural was found to be the main organic pollutant in the wastewater coming from the Diosgenin factory. This substance is derived from acidic pentosan in Dioscorea zingiberensis and is also found in a variety of agricultural byproducts, including corncobs, oat, wheat bran, and sawdust. It is regarded as a toxicant and an inhibitor to the growth of microorganism in both sewage disposal and biological fermentation. A furfural-degrading strain (DS1) was isolated from activated sludge of wastewater treatment plant in a diosgenin factory by continuous enrichment culture. The strain was identified as Bacillus cereus based on morphological, physiological tests, as well as on 16S rDNA sequence and Biolog analyses. The capacity of this strain to grow on a mineral salt medium, utilizing furfural as the sole carbon and energy source to degrade furfural, was investigated in this study. Under the condition of pH 9.0, temperature 35 °C, with rotating speed of 150 rpm, and an inoculum of 6 %, the strain showed that the furfural degradation capacity reaches 35 % in 7 days, as measured by high-performance liquid chromatography. The addition of inorganic carbon sources could bring down the biodegradation efficiency of the furfural. The strain DS1 showed better furfural removal capacity, as compared to other inorganic carbon sources in the media. Furthermore, a furfural concentration of as high as 4,000 mg L(-1) was tolerated by the culture. The capacity to degrade furfural was demonstrated for the first time by using the genus B. cereus. This study suggests the possible application in biodegradation strategies. PMID:25274411

  9. Structural basis of the substrate specificity of Bacillus cereus adenosine phosphorylase

    Energy Technology Data Exchange (ETDEWEB)

    Dessanti, Paola [Cornell University, Ithaca, NY 14853-1301 (United States); Università di Sassari, (Italy); Zhang, Yang [Cornell University, Ithaca, NY 14853-1301 (United States); Allegrini, Simone [Università di Sassari, (Italy); Tozzi, Maria Grazia [Università di Pisa, (Italy); Sgarrella, Francesco [Università di Sassari, (Italy); Ealick, Steven E., E-mail: see3@cornell.edu [Cornell University, Ithaca, NY 14853-1301 (United States)

    2012-03-01

    Adenosine phosphorylase from B. cereus shows a strong preference for adenosine over other 6-oxopurine nucleosides. Mutation of Asp204 to asparagine reduces the efficiency of adenosine cleavage but does not affect inosine cleavage, effectively reversing the substrate specificity. The structures of D204N complexes explain these observations. Purine nucleoside phosphorylases catalyze the phosphorolytic cleavage of the glycosidic bond of purine (2′-deoxy)nucleosides, generating the corresponding free base and (2′-deoxy)ribose 1-phosphate. Two classes of PNPs have been identified: homotrimers specific for 6-oxopurines and homohexamers that accept both 6-oxopurines and 6-aminopurines. Bacillus cereus adenosine phosphorylase (AdoP) is a hexameric PNP; however, it is highly specific for 6-aminopurines. To investigate the structural basis for the unique substrate specificity of AdoP, the active-site mutant D204N was prepared and kinetically characterized and the structures of the wild-type protein and the D204N mutant complexed with adenosine and sulfate or with inosine and sulfate were determined at high resolution (1.2–1.4 Å). AdoP interacts directly with the preferred substrate through a hydrogen-bond donation from the catalytically important residue Asp204 to N7 of the purine base. Comparison with Escherichia coli PNP revealed a more optimal orientation of Asp204 towards N7 of adenosine and a more closed active site. When inosine is bound, two water molecules are interposed between Asp204 and the N7 and O6 atoms of the nucleoside, thus allowing the enzyme to find alternative but less efficient ways to stabilize the transition state. The mutation of Asp204 to asparagine led to a significant decrease in catalytic efficiency for adenosine without affecting the efficiency of inosine cleavage.

  10. Structural basis of the substrate specificity of Bacillus cereus adenosine phosphorylase

    International Nuclear Information System (INIS)

    Adenosine phosphorylase from B. cereus shows a strong preference for adenosine over other 6-oxopurine nucleosides. Mutation of Asp204 to asparagine reduces the efficiency of adenosine cleavage but does not affect inosine cleavage, effectively reversing the substrate specificity. The structures of D204N complexes explain these observations. Purine nucleoside phosphorylases catalyze the phosphorolytic cleavage of the glycosidic bond of purine (2′-deoxy)nucleosides, generating the corresponding free base and (2′-deoxy)ribose 1-phosphate. Two classes of PNPs have been identified: homotrimers specific for 6-oxopurines and homohexamers that accept both 6-oxopurines and 6-aminopurines. Bacillus cereus adenosine phosphorylase (AdoP) is a hexameric PNP; however, it is highly specific for 6-aminopurines. To investigate the structural basis for the unique substrate specificity of AdoP, the active-site mutant D204N was prepared and kinetically characterized and the structures of the wild-type protein and the D204N mutant complexed with adenosine and sulfate or with inosine and sulfate were determined at high resolution (1.2–1.4 Å). AdoP interacts directly with the preferred substrate through a hydrogen-bond donation from the catalytically important residue Asp204 to N7 of the purine base. Comparison with Escherichia coli PNP revealed a more optimal orientation of Asp204 towards N7 of adenosine and a more closed active site. When inosine is bound, two water molecules are interposed between Asp204 and the N7 and O6 atoms of the nucleoside, thus allowing the enzyme to find alternative but less efficient ways to stabilize the transition state. The mutation of Asp204 to asparagine led to a significant decrease in catalytic efficiency for adenosine without affecting the efficiency of inosine cleavage

  11. Detection of Multiple Resistances, Biofilm Formation and Conjugative Transfer of Bacillus cereus from Contaminated Soils.

    Science.gov (United States)

    Anjum, Reshma; Krakat, Niclas

    2016-03-01

    The purpose of this study was to detect microbial resistances to a set of antibiotics/pesticides (multi-resistance) within pesticide and antibiotic-contaminated alluvial soils and to identify the corresponding antibiotic resistance genes (ARGs). To assess whether identified multi-resistant isolates are able to construct biofilms, several biofilm formation and conjugation experiments were conducted. Out of 35 isolates, six strains were used for filter mating experiments. Nine strains were identified by 16S rDNA gene sequence analyses and those were closely related to Pseudomonas sp., Citrobacter sp., Acinetobacter sp., Enterobacter sp., and in addition, Bacillus cereus was chosen for multi-resistant and pesticide-tolerant studies. Antibiotic-resistant and pesticide-tolerant bacterial strains were tested for the presence of ARGs. All nine strains were containing multiple ARGs (ampC, ermB, ermD, ermG, mecA, tetM) in different combinations. Interestingly, only strain WR34 (strongly related to Bacillus cereus) exhibited a high biofilm forming capacity on glass beads. Results obtained by filter mating experiments demonstrated gene transfer frequencies from 10(-5) to 10(-8). This study provides evidence that alluvial soils are hot spots for the accumulation of antibiotics, pesticides and biofilm formation. Particularly high resistances to tetracycline, ampicillin, amoxicillin and methicillin were proved. Apparently, isolate WR34 strongly correlated to a pathogenic organism had high potential to deploy biofilms in alluvial soils. Thus, we assume that loosened and unconsolidated soils investigated pose a high risk of an enhanced ARG prevalence. PMID:26650381

  12. Fate and effect of ingested Bacillus cereus spores and vegetative cells in the intestinal tract of human-flora-associated rats

    DEFF Research Database (Denmark)

    Wilcks, Andrea; Hansen, Bjarne Munk; Hendriksen, Niels Bohse; Licht, Tine Rask

    2006-01-01

    The fate and effect of Bacillus cereus F4433/73R in the intestine of human-flora-associated rats was studied using bacteriological culturing techniques and PCR-denaturing gradient gel electrophoresis in combination with cell assays and immunoassays for detection of enterotoxins. In faecal samples...... from animals receiving vegetative cells, only few B. cereus cells were detected. Spores survived the gastric barrier well, and were in some cases detected up to 2 weeks after ingestion. Selective growing revealed no major changes in the intestinal flora during passage of B. cereus. However, denaturing...... gradient gel electrophoresis analysis with universal 16S rRNA gene primers revealed significant changes in the intestinal microbiota of animals dosed with spores. Vero cell assays and a commercial kit (BCET-RPLA) did not reveal any enterotoxin production from B. cereus F4433/73R in the intestinal tract....

  13. Representing culture in interstellar messages

    Science.gov (United States)

    Vakoch, Douglas A.

    2008-09-01

    As scholars involved with the Search for Extraterrestrial Intelligence (SETI) have contemplated how we might portray humankind in any messages sent to civilizations beyond Earth, one of the challenges they face is adequately representing the diversity of human cultures. For example, in a 2003 workshop in Paris sponsored by the SETI Institute, the International Academy of Astronautics (IAA) SETI Permanent Study Group, the International Society for the Arts, Sciences and Technology (ISAST), and the John Templeton Foundation, a varied group of artists, scientists, and scholars from the humanities considered how to encode notions of altruism in interstellar messages . Though the group represented 10 countries, most were from Europe and North America, leading to the group's recommendation that subsequent discussions on the topic should include more globally representative perspectives. As a result, the IAA Study Group on Interstellar Message Construction and the SETI Institute sponsored a follow-up workshop in Santa Fe, New Mexico, USA in February 2005. The Santa Fe workshop brought together scholars from a range of disciplines including anthropology, archaeology, chemistry, communication science, philosophy, and psychology. Participants included scholars familiar with interstellar message design as well as specialists in cross-cultural research who had participated in the Symposium on Altruism in Cross-cultural Perspective, held just prior to the workshop during the annual conference of the Society for Cross-cultural Research . The workshop included discussion of how cultural understandings of altruism can complement and critique the more biologically based models of altruism proposed for interstellar messages at the 2003 Paris workshop. This paper, written by the chair of both the Paris and Santa Fe workshops, will explore the challenges of communicating concepts of altruism that draw on both biological and cultural models.

  14. Inhibition of Bacillus cereus growth by bacteriocin producing Bacillus subtilis isolated from fermented baobab seeds (maari) is substrate dependent.

    Science.gov (United States)

    Kaboré, Donatien; Nielsen, Dennis Sandris; Sawadogo-Lingani, Hagrétou; Diawara, Bréhima; Dicko, Mamoudou Hama; Jakobsen, Mogens; Thorsen, Line

    2013-03-01

    Maari is a spontaneously alkaline fermented food condiment made from baobab tree seeds. Due to the spontaneous nature of maari fermentations growth of the opportunistic human pathogen Bacillus cereus is occasionally observed. Bacillus subtilis strains are important for alkaline seed fermentations because of their enzymatic activities contributing to desirable texture, flavor and pH development. Some B. subtilis strains have antimicrobial properties against B. cereus. In the present work, three bacteriocin producing B. subtilis strains (B3, B122 and B222) isolated from maari were tested. The production of antimicrobial activity by the three strains was found to be greatly influenced by the substrate. All three B. subtilis strains produced antimicrobial activity against B. cereus NVH391-98 in BHI broth as determined by the agar well diffusion assay, whereas no antimicrobial activity was detected in whole cooked baobab seeds and in 10% (w/v) grinded baobab seeds. Incorporation of BHI with up to 5% (w/w) grinded baobab seeds enhanced the antimicrobial activity of B. subtilis compared with pure BHI in a strain dependent manner. Incorporation of BHI with 50% (w/w) baobab grinded seeds decreased the antimicrobial activity. Addition of the inorganic salts FeCl₃, MgSO₄ and MnSO₄ has previously been reported to increase bacteriocin production of B. subtilis, but the addition of these salts to 10% (w/v) grinded baobab seed broth did not cause antimicrobial activity. Survival of B. cereus NVH391-98 in co-culture with B. subtilis was tested in BHI broth, 10% (w/v) grinded baobab seed based broth and during baobab seed fermentation to produce maari. B. cereus NVH391-98 grew well in all three substrates in mono-culture. All the 3 B. subtilis strains were able to decrease B. cereus NVH391-98 to levels below the detection limit (starter culture candidates originating from maari which are able to prevent pathogen outgrowth remain to be identified. PMID:23376785

  15. Detection and sequencing of plasmid encoded tetracycline resistance determinants (tetA andtetB) from food-borneBacillus cereus isolates

    Institute of Scientific and Technical Information of China (English)

    Mudasir Ali Rather; Rabinder Singh Aulakh; Jatinder Paul Singh Gill; Abdul Qayoom Mir; Mir Nadeem Hassan

    2012-01-01

    Objective:To investigate the detection and sequencing of plasmid encoded tetracycline resistance genes(tetA andtetB) from food-borne and standard strains ofBacillus cereus(B. cereus).Methods:APCR was carried out to detect the tetracycline resistance genes(tetA and tetB) in food-borneB. cereus strains and the amplified products were sequenced.Results:The phenotypic resistance against tetracycline was observed in39 of the118 food-borne isolates and two reference strains(MTCC430 andMTCC1307) ofB. cereus.Among the phenotypically resistant isolates,tetA was detected in36 food-borne isolates and two reference strains(MTCC 430 andMTCC1307), whereas,tetB was detected in12 food-borne isolates andMTCC1307 strain. Conclusions:A close association was therefore found between phenotypic resistance against tetracycline and presence of tetracycline resistance genes.ThetetA andtetB gene fragments were amplified, purified and sequenced.The gene sequences of the isolates studied herein were found similar to tetA andtetB gene sequences of other bacteria available inNCBI.The occurrence oftetA and tetB genes inB. cereus indicate the horizontal transfer of antibiotic resistance determinants from other bacteria intoB. cereus.The transfer of these resistant determinants to other potentially pathogenic bacteria may be a matter of great concern.

  16. Involvement of calcium and dipicolinic acid in the resistance of Bacillus cereus BIS-59 spores to u.v. and gamma radiations

    International Nuclear Information System (INIS)

    The role of dipicolinic acid (DPA) in determining the resistance of Bacillus cereus spores to u.v. and gamma radiation was investigated. B. cereus BIS-59 spores containing varying amounts of DPA were prepared by appropriate compositional adjustments in the secondary media. Compared with spores containing 6% DPA (dry weight) those containing 0.8% DPA were far more sensitive to u.v. radiation. Similar u.v. radiation sensitivity was also found in respect of a DPA-less mutant of B. cereus T 6A 1. Pre-treatment of DPA deficient spores (of wild type or mutant B. cereus) with DPA or the presence of DPA during irradiation resulted in increased resistance of these spores to u.v. radiation. In the range 0.2 to 1% DPA content of spores of B. cereus BIS-59, a striking inverse relationship could be discerned between the DPA content and the number of spore photo-products (5-thymidyl, 5,6-dihydrothymine) formed in DNA and spore viability. The resistance of B. cereus spores to gamma radiation did not seem to be influenced by their DPA content. (author)

  17. Efecto Antagónico del Kefir sobre Endosporas y Células Vegetativas de Bacillus Cereus y Clostridium Perfringens Antagonistic Effect of the Kefir on Endospores and Vegetative Cells of Bacillus Cereus and Clostridium Perfringens

    OpenAIRE

    Ricardo J Anselmo; Silvia S Viora; Pablo A Ojeda; Lucía I Lausada

    2010-01-01

    Se estudió el efecto bactericida del kéfir sobre endosporas y células vegetativas de Bacillus cereus y Clostridium perfringens inoculados en kéfir durante su almacenamiento. Muestras de kéfir de dos procedencias, uno de origen italiano y otro peruano, fueron inoculadas con una población conocida de B. cereus y Cl. perfringens (10(6) UFC/mL) y conservados a 4ºC durante 30 días. Cada dos días se realizó un recuento de bacterias lácticas, de levaduras, de los patógenos agregados y se determinó e...

  18. Ces locus embedded proteins control the non-ribosomal synthesis of the cereulide toxin in emetic Bacillus cereus on multiple levels

    Science.gov (United States)

    Lücking, Genia; Frenzel, Elrike; Rütschle, Andrea; Marxen, Sandra; Stark, Timo D.; Hofmann, Thomas; Scherer, Siegfried; Ehling-Schulz, Monika

    2015-01-01

    The emetic toxin cereulide produced by Bacillus cereus is synthesized by the modular enzyme complex Ces that is encoded on a pXO1-like megaplasmid. To decipher the role of the genes adjacent to the structural genes cesA/cesB, coding for the non-ribosomal peptide synthetase (NRPS), gene inactivation- and overexpression mutants of the emetic strain F4810/72 were constructed and their impact on cereulide biosynthesis was assessed. The hydrolase CesH turned out to be a part of the complex regulatory network controlling cereulide synthesis on a transcriptional level, while the ABC transporter CesCD was found to be essential for post-translational control of cereulide synthesis. Using a gene inactivation approach, we show that the NRPS activating function of the phosphopantetheinyl transferase (PPtase) embedded in the ces locus was complemented by a chromosomally encoded Sfp-like PPtase, representing an interesting example for the functional interaction between a plasmid encoded NRPS and a chromosomally encoded activation enzyme. In summary, our results highlight the complexity of cereulide biosynthesis and reveal multiple levels of toxin formation control. ces operon internal genes were shown to play a pivotal role by acting at different levels of toxin production, thus complementing the action of the chromosomal key transcriptional regulators AbrB and CodY. PMID:26528255

  19. The Role of Active Site Flexible Loops in Catalysis and of Zinc in Conformational Stability of Bacillus cereus 569/H/9 β-Lactamase.

    Science.gov (United States)

    Montagner, Caroline; Nigen, Michaël; Jacquin, Olivier; Willet, Nicolas; Dumoulin, Mireille; Karsisiotis, Andreas Ioannis; Roberts, Gordon C K; Damblon, Christian; Redfield, Christina; Matagne, André

    2016-07-29

    Metallo-β-lactamases catalyze the hydrolysis of most β-lactam antibiotics and hence represent a major clinical concern. The development of inhibitors for these enzymes is complicated by the diversity and flexibility of their substrate-binding sites, motivating research into their structure and function. In this study, we examined the conformational properties of the Bacillus cereus β-lactamase II in the presence of chemical denaturants using a variety of biochemical and biophysical techniques. The apoenzyme was found to unfold cooperatively, with a Gibbs free energy of stabilization (ΔG(0)) of 32 ± 2 kJ·mol(-1) For holoBcII, a first non-cooperative transition leads to multiple interconverting native-like states, in which both zinc atoms remain bound in an apparently unaltered active site, and the protein displays a well organized compact hydrophobic core with structural changes confined to the enzyme surface, but with no catalytic activity. Two-dimensional NMR data revealed that the loss of activity occurs concomitantly with perturbations in two loops that border the enzyme active site. A second cooperative transition, corresponding to global unfolding, is observed at higher denaturant concentrations, with ΔG(0) value of 65 ± 1.4 kJ·mol(-1) These combined data highlight the importance of the two zinc ions in maintaining structure as well as a relatively well defined conformation for both active site loops to maintain enzymatic activity. PMID:27235401

  20. Bioaccumulation of cerium and neodymium by Bacillus cereus isolated from rare earth environments of Chavara and Manavalakurichi, India

    International Nuclear Information System (INIS)

    Rare earth elements (REEs) are among the common minerals in the Rare earth environment that are very precious and also enhance soil properties. The aim of this present study is to evaluate the accumulation of REEs by bacterial isolates of rare earth environment. Morphological and biochemical characterization were done for 37 bacterial isolates and also molecular studies were carried out using 16S rRNA sequencing method. The assessment of REEs composition in soil samples of Chavara and Manavalakurichi analyzed using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) showed the abundance of Cerium and Neodymium among lanthanides. The bioaccumulation study of rare earth elements by Bacillus cereus were accomplished employing FT-IR spectrum and ICP-OES analysis. The significant accumulation of rare earth elements especially Cerium and Neodymium was noticed in Bacillus cereus isolated from rare earth environment. (author)

  1. Biodegradation of real petroleum wastewater by immobilized hyper phenol-tolerant strains of Bacillus cereus in a fluidized bed bioreactor

    OpenAIRE

    Banerjee, Aditi; Ghoshal, Aloke K.

    2016-01-01

    Microbial bioremediation of petroleum wastewater by phenol-degrading-bacteria holds promise in circumventing the issue of petroleum-spill related pollution. Herein, biodegradation of petroleum wastewater samples collected from oil refinery site was carried out in a fluidized bed bioreactor by Ca-alginate immobilized biomass of phenol-degrading strains of Bacillus cereus (AKG1 MTCC9817 and AKG2 MTCC9818). Degradation performance of the system was evaluated by measuring the changes in chemical ...

  2. Cost-effective-substrates for production of poly-β-hydroxybutyrate by a newly isolated Bacillus cereus PS-10.

    Science.gov (United States)

    Sharma, Priyanka; Bajaj, Bijender Kumar

    2015-11-01

    Poly-β-hydroxybutyrate (PHB) may serve as one of the imperative substitutes for petroleum derived plastics because of their close functional analogy and biodegradation quality. In the present study, PHB producing ability of bacterial isolates was examined on low-cost agro industrial residues. Isolate PS-10 from domestic waste landfills, identified as Bacillus cereus PS-10 produced and accumulated appreciable amount of PHB. Bacillus cereus PS-10 was capable of using a wide variety of agro-based residues viz. maize bran, rice husk, wood waste, molasses, whey etc. as cost-effective carbon sources for PHB production. Molasses at 3% (w/v) supported maximum PHB production (9.5 gl(-1)) and was followed by glycerol (8.9 gl(-1)) at 2% (w/v). Certain carbon sources like almond shell powder and walnut shell powder are being reported for the first time for PHB production and supported reasonable PHB yield i.e. 6.6 and 4.6 gl(-1), respectively. Different cost-effective nitrogen sources like corn steep liquor, chick pea bran, soy bean meal, mustard cake etc. were used for PHB production. Highest PHB production was observed at pH 7 (9.6 gl(-1)) after 48 hrs of fermentation, although B. cereus PS-10 grew and produced PHB over pH range of 5-9. Optimum inoculum level for maximum PHB production was found to be 5% v/v (A600 0.9; approximately 10(8) cfu ml(-1)). Fourier transform infrared spectroscopy (FT-IR) analysis of the extracted PHB showed characteristic peaks (1721.95, 1632.19 and 2926.43 cm(-1)) similar to standard PHB. Melting point of PHB was found to be 185°C. Bacillus cereus PS-10 may be a sound PHB producer, especially by exploiting low cost substrates. PMID:26688964

  3. Bacillus cereus food poisoning associated with fried rice at two child day care centers--Virginia, 1993.

    Science.gov (United States)

    1994-03-18

    Bacillus cereus, an infectious cause of foodborne illness, accounted for 2% of outbreaks with confirmed etiology that were reported to CDC during 1973-1987 (1). On July 21, 1993, the Lord Fairfax (Virginia) Health District received reports of acute gastrointestinal illness that occurred among children and staff at two jointly owned child day care centers following a catered lunch. This report summarizes the investigation of this outbreak. PMID:8121375

  4. Iron acquisition in Bacillus cereus: the roles of IlsA and bacillibactin in exogenous ferritin iron mobilization.

    Directory of Open Access Journals (Sweden)

    Diego Segond

    2014-02-01

    Full Text Available In host-pathogen interactions, the struggle for iron may have major consequences on the outcome of the disease. To overcome the low solubility and bio-availability of iron, bacteria have evolved multiple systems to acquire iron from various sources such as heme, hemoglobin and ferritin. The molecular basis of iron acquisition from heme and hemoglobin have been extensively studied; however, very little is known about iron acquisition from host ferritin, a 24-mer nanocage protein able to store thousands of iron atoms within its cavity. In the human opportunistic pathogen Bacillus cereus, a surface protein named IlsA (Iron-regulated leucine rich surface protein type A binds heme, hemoglobin and ferritin in vitro and is involved in virulence. Here, we demonstrate that IlsA acts as a ferritin receptor causing ferritin aggregation on the bacterial surface. Isothermal titration calorimetry data indicate that IlsA binds several types of ferritins through direct interaction with the shell subunits. UV-vis kinetic data show a significant enhancement of iron release from ferritin in the presence of IlsA indicating for the first time that a bacterial protein might alter the stability of the ferritin iron core. Disruption of the siderophore bacillibactin production drastically reduces the ability of B. cereus to utilize ferritin for growth and results in attenuated bacterial virulence in insects. We propose a new model of iron acquisition in B. cereus that involves the binding of IlsA to host ferritin followed by siderophore assisted iron uptake. Our results highlight a possible interplay between a surface protein and a siderophore and provide new insights into host adaptation of B. cereus and general bacterial pathogenesis.

  5. Postincision steps of photoproduct removal in a mutant of Bacillus cereus 569 that produces UV-sensitive spores.

    OpenAIRE

    Weinberger, S; Evenchick, Z; Hertman, I

    1983-01-01

    An excision-defective mutant of Bacillus cereus 569 is normal in incision and repair synthesis, but rejoining of incision breaks is defective, resulting in accumulation of low-molecular-weight DNA after UV irradiation. The defect in removal of photoproducts by exonuclease after incision renders both vegetative cells and dormant spores of the mutant sensitive to UV. A similarity is indicated to the uvrD mutation described recently in Escherichia coli.

  6. Combined effect of anaerobiosis, low pH and cold temperatures on the growth capacities of psychrotrophic Bacillus cereus.

    Science.gov (United States)

    Guérin, Alizée; Dargaignaratz, Claire; Broussolle, Véronique; Clavel, Thierry; Nguyen-The, Christophe

    2016-10-01

    Psychrotrophic strains of the foodborne pathogen Bacillus cereus can multiply during the refrigerated storage of food products. The aim of this study was to determine the impact of anaerobiosis on the growth of two psychrotrophic B. cereus strains exposed to acidic pH at a cold temperature in a laboratory medium. At 10 °C, growth occurred at pH values equal to or higher than 5.7 during anaerobiosis, whereas aerobic growth was observed from pH 5.4. Growth rates during aerobiosis were similar at pH 5.4 and pH 7. No growth was observed for the two tested strains at 8 °C without oxygen regardless of the pH; however, both strains grew at this temperature from pH 5.4 in the presence of oxygen. These pH growth limits in aerobiosis are consistent with those reported for different strains and different foods or media, but no other studies have described anaerobic growth at acidic pH values. The maximal B. cereus concentration was approximately 6.0 log10 CFU/ml for cultures in the absence of oxygen and approximately 8.0 log10 CFU/ml for cultures in the presence of oxygen. In conclusion, we found that the combination of anaerobiosis, pH < 5.7 at 10 °C, or anaerobiosis and temperatures ≤8 °C prevent psychrotrophic B. cereus growth. PMID:27375252

  7. Phosphatidylinositol-specific phospholipase C from Bacillus cereus combines intrinsic phosphotransferase and cyclic phosphodiesterase activities: A 31P NMR study

    International Nuclear Information System (INIS)

    The inositol phosphate products formed during the cleavage of phosphatidylinositol by phosphatidylinositol-specific phospholipase C from Bacillus cereus were analyzed by 31P NMR. 31P NMR spectroscopy can distinguish between the inositol phosphate species and phosphatidylinositol. Chemical shift values (with reference to phosphoric acid) observed are -0.41, 3.62, 4.45, and 16.30 ppm for phosphatidylinositol, myo-inositol 1-monophosphate, myo-inositol 2-monophosphate, and myo-inositol 1,2-cyclic monophosphate, respectively. It is shown that under a variety of experimental conditions this phospholipase C cleaves phosphatidylinositol via an intramolecular phosphotransfer reaction producing diacylglycerol and D-myo-inositol 1,2-cyclic monophosphate. The authors also report the new and unexpected observation that the phosphatidylinositol-specific phospholipase C from B. cereus is able to hydrolyze the inositol cyclic phosphate to form D-myo-inositol 1-monophosphate. The enzyme, therefore, possesses phosphotransferase and cyclic phosphodiesterase activities. The second reaction requires thousandfold higher enzyme concentrations to be observed by 31P NMR. This reaction was shown to be regiospecific in that only the 1-phosphate was produced and stereospecific in that only D-myo-inositol 1,2-cyclic monophosphate was hydrolyzed. Inhibition with a monoclonal antibody specific for the B.cereus phospholipase C showed that the cyclic phosphodiesterase activity is intrinsic to the bacterial enzyme. They propose a two-step mechanism for the phosphatidyl-inositol-specific phospholipase C from B. cereus involving sequential phosphotransferase and cyclic phosphodiesterase activities. This mechanism bears a resemblance to the well-known two-step mechanism of pancreatic ribonuclease, RNase A

  8. ANTIBACTERIAL EFFECT OF GARLIC (ALLIUM SATIVUM) AND GINGER (ZINGIBER OFFICINALE) AGAINST STAPHYLOCOCCUS AUREUS, SALMONELLA TYPHI, ESCHERICHIA COLI AND BACILLUS CEREUS

    OpenAIRE

    Bandna Chand

    2013-01-01

    Antibacterial activity of extracts of Allium sativum (garlic) and Zingiber officinale (ginger) has been evaluated against four different bacteria namely Escherichia coli, Salmonella Typhi, Staphylococcus aureus and Bacillus cereus. Two methods were used to determine the antimicrobial activity of garlic and ginger extracts namely disk diffusion method and agar well diffusion method. Garlic extract exhibited excellent antibacterial activity against all four test organisms while ginger extract s...

  9. A new species of Lachesilla (Psocodea: 'Psocoptera': Lachesillidae from Dominica, representing a new species group Una especie nueva de Lachesilla (Psocodea: 'Psocoptera': Lachesillidae de Dominica, que representa un nuevo grupo de especies

    Directory of Open Access Journals (Sweden)

    Alfonso N. García Aldrete

    2011-06-01

    Full Text Available A new species of Lachesilla, from Cabrits National Park, St. John's Parish, Dominica, is here described and illustrated. The phallosome is V-shaped, and it is autapomorphic in having the distal ends of the apodeme arms articulated to each clasper. Based on these characters, a new species group is created, close to the L. forcepeta and L. palmera species groups (the latter also diagnosed in this paper. The holotype is deposited in the National Insect Collection (CNIN, Instituto de Biología, Universidad Nacional Autónoma de México, Mexico City.Se describe e ilustra una nueva especie de Lachesilla, procedente de Cabrits National Park, St. John's Parish, Dominica. El falosoma tiene forma de V, y es autapomórfico en tener los extremos distales de los brazos articulados a cada clásper. Con base en estos caracteres, se crea un nuevo grupo de especies, cercano a los grupos de L. forcepeta y L. palmera (este último también definido en este trabajo. El holotipo está depositado en la Colección Nacional de Insectos (CNIN, alojada en el Instituto de Biología de la Universidad Nacional Autónoma de México, México, D. F.

  10. Glucose 6P binds and activates HlyIIR to repress Bacillus cereus haemolysin hlyII gene expression.

    Directory of Open Access Journals (Sweden)

    Elisabeth Guillemet

    Full Text Available Bacillus cereus is a Gram-positive spore-forming bacterium causing food poisoning and serious opportunistic infections. These infections are characterized by bacterial accumulation despite the recruitment of phagocytic cells. We have previously shown that B. cereus Haemolysin II (HlyII induces macrophage cell death by apoptosis. In this work, we investigated the regulation of the hlyII gene. We show that HlyIIR, the negative regulator of hlyII expression in B. cereus, is especially active during the early bacterial growth phase. We demonstrate that glucose 6P directly binds to HlyIIR and enhances its activity at a post-transcriptional level. Glucose 6P activates HlyIIR, increasing its capacity to bind to its DNA-box located upstream of the hlyII gene, inhibiting its expression. Thus, hlyII expression is modulated by the availability of glucose. As HlyII induces haemocyte and macrophage death, two cell types that play a role in the sequestration of nutrients upon infection, HlyII may induce host cell death to allow the bacteria to gain access to carbon sources that are essential components for bacterial growth.

  11. The survival and growth of Bacillus cereus in boiled and fried rice in relation to outbreaks of food poisoning.

    Science.gov (United States)

    Gilbert, R J; Stringer, M F; Peace, T C

    1974-12-01

    A number of outbreaks of food poisoning attributed to Bacillus cereus have been reported recently and all have been associated with cooked rice usually from Chinese restaurants and ;take-away' shops.Tests were made to assess the heat resistance of B. cereus spores in aqueous suspension, the growth of the organism in boiled rice stored at temperatures in the range 4-55 degrees C., and the effect of cooking and storage on the growth of the organism in boiled and fried rice. The spores of B. cereus survived cooking and were capable of germination and outgrowth. The optimum temperature for growth in boiled rice was between 30 degrees and 37 degrees C. and growth also occurred during storage at 15 degrees and 43 degrees C.To prevent further outbreaks it is suggested that rice should be boiled in smaller quantities on several occasions during the day, thereby reducing the storage time before frying. After boiling the rice should either be kept hot (> 63 degrees C.) or cooled quickly and transferred to a refrigerator within 2 hr. of cooking. Boiled or fried rice must not be stored under warm conditions especially in the range 15-50 degrees C. PMID:4216605

  12. Purification of a thermostable chitinase from Bacillus cereus by chitin affinity and its application in microbial community changes in soil.

    Science.gov (United States)

    Liang, Tzu-Wen; Hsieh, Tung-Yen; Wang, San-Lang

    2014-06-01

    A thermostable chitinase was purified by chitin affinity from the culture supernatant of Bacillus cereus TKU028 with shrimp head powder (SHP) as the sole carbon/nitrogen source. TKU028 chitinase was purified using a one-step affinity adsorbent system, and the molecular mass of TKU028 chitinase (approximately 40 kDa) was then determined using SDS-PAGE. The enzyme was stable for 60 min at temperatures below 60 °C and stable over a broad pH range of 4-9 for 60 min. In addition, the temporal changes of a bacterial community in mangrove river sediment of the Tamsui River with added SHP were also analysed by PCR-denaturing gradient gel electrophoresis to investigate the effects of B. cereus TKU028 on the degradation of SHP. The 6-week incubation sample of SHP and B. cereus TKU028-amended mangrove river sediment displayed the highest amount of biomass, reducing sugar and total sugar, and some variance of bacterial community composition existed in the soils. PMID:24342954

  13. Probiotic actions of Bacillus cereus var. toyoi and Saccharomyces boulardii in silver catfish (Rhamdia quelen larvae culture

    Directory of Open Access Journals (Sweden)

    Diego Moreira de Souza

    2012-03-01

    Full Text Available The objective of this study was to evaluate the use of Bacillus cereus var. toyoi and Saccharomyces boulardii as probiotics to improve Rhamdia quelen culture. Six hundred larvaes (0.16±0.07 g were divided in three replicate tanks (25-L recirculation, 20 ºC, photoperiod of 12 h light/12 h darkness per treatment and were randomly assigned to the following treatments: Bacillus cereus var. toyoi; Saccharomyces boulardii; B. toyoi and S. boulardii; and control (without probiotic addition for a period of 30 days. The fish were fed five times daily (56% crude protein - Supra alevino inicial® and the probiotics were applied in water once a day. The doses of probiotics were 5 × 10(8 and 2 × 10(9 CFU (colony forming unit/mL for B. cereus var. toyoi and S. boulardii, respectively. Both probiotics have an inhibitory effect in vitro against Vibrio carchariae and are able to grow in media prepared with fishery water; however, no effect was observed on growth parameters when they were administered to Rhamdia quelen larvae.

  14. Isolation and Molecular Characterization of Potential Plant Growth Promoting Bacillus cereus GGBSTD1 and Pseudomonas spp. GGBSTD3 from Vermisources

    Directory of Open Access Journals (Sweden)

    Balayogan Sivasankari

    2014-01-01

    Full Text Available Vermicompost was prepared from leaf materials of Gliricidia sepium + Cassia auriculata + Leucaena leucocephala with cow dung (1 : 1 : 2 using Eudrilus eugeniae (Kinberg and Eisenia fetida for 60 days. Nineteen bacterial strains which have the capability to fix nitrogen, solubilize inorganic phosphate, and produce phytohormones were isolated from vermicompost, vermisources, and earthworm (fore, mid, and hind guts and tested for plant growth studies. Among the bacterial strains only five strains had both activities; among the five Bacillus spp. showed more nitrogen fixing activity and Pseudomonas spp. showed more phosphate solubilizing activity. Hence these bacterial strains were selected for further molecular analysis and identified Bacillus cereus GGBSTD1 and Pseudomonas spp. GGBSTD3. Plant growth studies use these two organisms separately and as consortium (Bacillus cereus + Pseudomonas spp. in (1 : 1 ratio at different concentrations using Vigna unguiculata (L. Walp. at different day intervals. The germination percent, shoot length, root length, leaf area, chlorophyll a content of the leaves, chlorophyll b content of the leaves, total chlorophyll content of the leaves, fresh weight of the whole plant, and dry weight of the whole plant were significantly enhanced by the consortium (Bacillus cereus + Pseudomonas spp. of two organisms at 5 mL concentrations on the 15th day compared to others.

  15. Effect of combined radiation and NaOCl/ultrasonication on reduction of Bacillus cereus spores in rice

    Science.gov (United States)

    Ha, Ji-Hyoung; Kim, Hyun-Joo; Ha, Sang-Do

    2012-08-01

    In this study, ionizing radiation in combination with sodium hypochlorite (NaOCl) and ultrasonication (US) was examined for its effectiveness in reducing Bacillus cereus F4810/72 spores in raw rice. We also evaluated whether the combined processing would produce synergistic effects compared to the individual treatments. The concentration of the initial B. cereus spore was approximately 2.9 log10 CFU/g. After 0.1, 0.2 and 0.3 kGy irradiation treatment, spore populations were reduced by 1.3, 1.4 and 1.6 log10 CFU/g, respectively. In the case of combined gamma irradiation and NaOCl/US treatment, the reduction was higher than those of each single treatment. The combined treatment of 0.1, 0.2 and 0.3 kGy and NaOCl (600-1000 ppm)/US (5-20 min) completely destroyed the spores in raw rice while the spores were not completely destroyed in the control treatment (0 kGy). These results indicated that it could be more effective to combine NaOCl with low dose gamma irradiation than high dose (concentration) of individual disinfection treatment to destroy B. cereus spores in food such as raw rice.

  16. Photoproduct formation and repair capacity in a mutant of Bacillus cereus 569 producing UV-sensitive spores

    International Nuclear Information System (INIS)

    A mutant of Bacillus cereus 569 UV sensitive in both vegetative and sporal stages was isolated by N-methyl-N'-nitro-N-nitrosoguanidine (NTG) mutagenesis followed by selection on mitomycin C. The UV-sensitive mutant designated as B. cereus 2422 exhibited normal content of dipicolinic acid (DPA) and resistance to X-rays and ethyl methanesulphonate. The photoproduct type and amount, induced by a given UV dose, was similar in either cells or spores of both the mutant 2422 and the wild-type ancestor. The mutant 2422 excised cyclobutane thymine dimers only to a limited extent (20%) as compared with 80% removal in the wild type. Removal of a spore-specific photoproduct (TDHT) during germination proceeded to a similar extent in B. cereus 2422 and the wild-type parent. However, under growing conditions, an additional removal of the TDHT was observed only in the wild-type strain. Liquid holding recovery occurred in irradiated wild-type cells, but not in mutant cells. Spontaneous revertants were isolated that regained UV resistance simultaneously in both the vegetative and sporal stage. (orig./AJ)

  17. Biocatalytic Resolution of Rac-α-Ethyl-2-Oxo-Pyrrolidineacetic Acid Methyl Ester by Immobilized Recombinant Bacillus cereus Esterase.

    Science.gov (United States)

    Zheng, Jian-Yong; Liu, Yin-Yan; Luo, Wei-Feng; Zheng, Ren-Chao; Ying, Xiang-Xian; Wang, Zhao

    2016-04-01

    A new esterase-producing strain (Bacillus cereus WZZ001) which exhibiting high hydrolytic activity and excellent enantioselectivity on rac-α-ethyl-2-oxo-pyrrolidineacetic acid methyl ester (R, S-1) has been isolated from soil sample by our laboratory. In this study, the stereoselective hydrolysis of (R, S-1) was performed using the recombinant Bacillus cereus esterase which expressed in Escherichia coli BL21 (DE3). Under the optimized conditions of pH 8.0, 35 °C, and concentration of substrate 400 mM, a successful enzymatic resolution was achieved with an e.e. s of 99.5 % and conversion of 49 %. Immobilization considerably increased the reusability of the recombinant esterase; the immobilized enzyme showed excellent reusability during 6 cycles of repeated 2 h reactions at 35 °C. Thereby, it makes the recombinant B. cereus esterase a usable biocatalyst for industrial application. PMID:26695776

  18. Spectroscopic studies of the iron and manganese reconstituted tyrosyl radical in Bacillus cereus ribonucleotide reductase R2 protein.

    Directory of Open Access Journals (Sweden)

    Ane B Tomter

    Full Text Available Ribonucleotide reductase (RNR catalyzes the rate limiting step in DNA synthesis where ribonucleotides are reduced to the corresponding deoxyribonucleotides. Class Ib RNRs consist of two homodimeric subunits: R1E, which houses the active site; and R2F, which contains a metallo cofactor and a tyrosyl radical that initiates the ribonucleotide reduction reaction. We studied the R2F subunit of B. cereus reconstituted with iron or alternatively with manganese ions, then subsequently reacted with molecular oxygen to generate two tyrosyl-radicals. The two similar X-band EPR spectra did not change significantly over 4 to 50 K. From the 285 GHz EPR spectrum of the iron form, a g(1-value of 2.0090 for the tyrosyl radical was extracted. This g(1-value is similar to that observed in class Ia E. coli R2 and class Ib R2Fs with iron-oxygen cluster, suggesting the absence of hydrogen bond to the phenoxyl group. This was confirmed by resonance Raman spectroscopy, where the stretching vibration associated to the radical (C-O, ν(7a = 1500 cm(-1 was found to be insensitive to deuterium-oxide exchange. Additionally, the (18O-sensitive Fe-O-Fe symmetric stretching (483 cm(-1 of the metallo-cofactor was also insensitive to deuterium-oxide exchange indicating no hydrogen bonding to the di-iron-oxygen cluster, and thus, different from mouse R2 with a hydrogen bonded cluster. The HF-EPR spectrum of the manganese reconstituted RNR R2F gave a g(1-value of ∼2.0094. The tyrosyl radical microwave power saturation behavior of the iron-oxygen cluster form was as observed in class Ia R2, with diamagnetic di-ferric cluster ground state, while the properties of the manganese reconstituted form indicated a magnetic ground state of the manganese-cluster. The recent activity measurements (Crona et al., (2011 J Biol Chem 286: 33053-33060 indicates that both the manganese and iron reconstituted RNR R2F could be functional. The manganese form might be very important, as it has 8

  19. Bacillus cereus as indicator in the sterilization of residual water with high energy electrons; Bacillus cereus como indicador en la desinfeccion de aguas residuales con electrones de alta energia

    Energy Technology Data Exchange (ETDEWEB)

    Mejia Z, E

    2000-07-01

    One of the main causes of water pollution is the presence of microorganisms that provoke infections, moreover of chemical substances. The processes of residual water treatment finally require of the disinfection for its use or final disposition. The radiation technology for the residual water treatment by mean of electron beams is an innovator process because as well as decomposing the chemical substance or to degrade them, also it provokes a disinfection by which this is proposed as alternative for disinfection of residual water, with the purpose in reusing the water treated in the agriculture, recreation and industry among others secondary activities, solving environmental or health problems. The objective of this work is to evaluate the use of Bacillus cereus as biological indicator in the disinfection by radiation, using High Energy Electrons. To fulfil with this objective, the work was developed in three stages, the first one consisted in the acquisition, propagation and conservation of the Bacillus cereus stumps, considering Escherichia coli and Salmonella typhimurium as pathogenic germs present in residual water. Moreover, the inocule standardization and the conditions of the Electron accelerator Type Pelletron. In the second stage it was performed the irradiation of aqueous samples of the microorganisms simulating biological pollution and the application to problem samples of a treatment plant sited in the Lerma River zone of mixed residual water. And in the third stage was performed a regression analysis to the reported survival for each kind of microorganisms. The results obtained show that with the use of Electron beams was reduced 6 logarithmic units de E. coli at 129 Gy, for S. typhimurium it was reduced 8 logarithmic units at 383 Gy and the B. cereus at 511 Gy was reduced 6.8 logarithmic units. Of the problem samples irradiated at 500 Gy, the concentration of the total account diminished from 8.70 x 10{sup 7} UFC/ml to 550 UFC/ml, the presence of B

  20. OSMOSE experiment representativity studies

    International Nuclear Information System (INIS)

    The OSMOSE program aims at improving the neutronic predictions of advanced nuclear fuels through measurements in the MINERVE facility at the CEA-Cadarache (France) on samples containing the following separated actinides: Th-232, U-233, U-234, U-235, U-236, U-238, Np-237, Pu-238, Pu-239, Pu-240, Pu-241, Pu-242, Am-241, Am-243, Cm-244 and Cm-245. The goal of the experimental measurements is to produce a database of reactivity-worth measurements in different neutron spectra for the separated heavy nuclides. This database can then be used as a benchmark for integral reactivity-worth measurements to verify and validate reactor analysis codes and integral cross-section values for the isotopes tested. In particular, the OSMOSE experimental program will produce very accurate sample reactivity-worth measurements for a series of actinides in various spectra, from very thermalized to very fast. The objective of the analytical program is to make use of the experimental data to establish deficiencies in the basic nuclear data libraries, identify their origins, and provide guidelines for nuclear data improvements in coordination with international programs. To achieve the proposed goals, seven different neutron spectra can be created in the MINERVE facility: UO2 dissolved in water (representative of over-moderated LWR systems), UO2 matrix in water (representative of LWRs), a mixed oxide fuel matrix, two thermal spectra containing large epithermal components (representative of under-moderated reactors), a moderated fast spectrum (representative of fast reactors which have some slowing down in moderators such as lead-bismuth or sodium), and a very hard spectrum (representative of fast reactors with little moderation from reactor coolant). The different spectra are achieved by changing the experimental lattice within the MINERVE reactor. The experimental lattice is the replaceable central part of MINERVE, which establishes the spectrum at the sample location. This configuration

  1. OSMOSE experiment representativity studies.

    Energy Technology Data Exchange (ETDEWEB)

    Aliberti, G.; Klann, R.; Nuclear Engineering Division

    2007-10-10

    The OSMOSE program aims at improving the neutronic predictions of advanced nuclear fuels through measurements in the MINERVE facility at the CEA-Cadarache (France) on samples containing the following separated actinides: Th-232, U-233, U-234, U-235, U-236, U-238, Np-237, Pu-238, Pu-239, Pu-240, Pu-241, Pu-242, Am-241, Am-243, Cm-244 and Cm-245. The goal of the experimental measurements is to produce a database of reactivity-worth measurements in different neutron spectra for the separated heavy nuclides. This database can then be used as a benchmark for integral reactivity-worth measurements to verify and validate reactor analysis codes and integral cross-section values for the isotopes tested. In particular, the OSMOSE experimental program will produce very accurate sample reactivity-worth measurements for a series of actinides in various spectra, from very thermalized to very fast. The objective of the analytical program is to make use of the experimental data to establish deficiencies in the basic nuclear data libraries, identify their origins, and provide guidelines for nuclear data improvements in coordination with international programs. To achieve the proposed goals, seven different neutron spectra can be created in the MINERVE facility: UO2 dissolved in water (representative of over-moderated LWR systems), UO2 matrix in water (representative of LWRs), a mixed oxide fuel matrix, two thermal spectra containing large epithermal components (representative of under-moderated reactors), a moderated fast spectrum (representative of fast reactors which have some slowing down in moderators such as lead-bismuth or sodium), and a very hard spectrum (representative of fast reactors with little moderation from reactor coolant). The different spectra are achieved by changing the experimental lattice within the MINERVE reactor. The experimental lattice is the replaceable central part of MINERVE, which establishes the spectrum at the sample location. This configuration

  2. Adhesion and removal kinetics of Bacillus cereus biofilms on Ni-PTFE modified stainless steel.

    Science.gov (United States)

    Huang, Kang; McLandsborough, Lynne A; Goddard, Julie M

    2016-01-01

    Biofilm control remains a challenge to food safety. A well-studied non-fouling coating involves codeposition of polytetrafluoroethylene (PTFE) during electroless plating. This coating has been reported to reduce foulant build-up during pasteurization, but opportunities remain in demonstrating its efficacy in inhibiting biofilm formation. Herein, the initial adhesion, biofilm formation, and removal kinetics of Bacillus cereus on Ni-PTFE-modified stainless steel (SS) are characterized. Coatings lowered the surface energy of SS and reduced biofilm formation by > 2 log CFU cm(-2). Characterization of the kinetics of biofilm removal during cleaning demonstrated improved cleanability on the Ni-PTFE coated steel. There was no evidence of biofilm after cleaning by either solution on the Ni-PTFE coated steel, whereas more than 3 log and 1 log CFU cm(-2) of bacteria remained on the native steel after cleaning with water and an alkaline cleaner, respectively. This work demonstrates the potential application of Ni-PTFE non-fouling coatings on SS to improve food safety by reducing biofilm formation and improving the cleaning efficiency of food processing equipment. PMID:27020838

  3. Antioxidant and DNA Damage Protecting Activity of Exopolysaccharides from the Endophytic Bacterium Bacillus cereus SZ1

    Directory of Open Access Journals (Sweden)

    Li Ping Zheng

    2016-02-01

    Full Text Available An endophytic bacterium was isolated from the Chinese medicinal plant Artemisia annua L. The phylogenetic and physiological characterization indicated that the isolate, strain SZ-1, was Bacillus cereus. The endophyte could produce an exopolysaccharide (EPS at 46 mg/L. The 1,1-diphenyl-2-picrylhydracyl (DPPH radical scavenging activity of the EPS reached more than 50% at 3–5 mg/mL. The EPS was also effective in scavenging superoxide radical in a concentration dependent fashion with an EC50 value of 2.6 mg/mL. The corresponding EC50 for scavenging hydroxyl radical was 3.1 mg/mL. Moreover, phenanthroline-copper complex-mediated chemiluminescent emission of DNA damage was both inhibited and delayed by EPS. The EPS at 0.7–1.7 mg/mL also protected supercoiled DNA strands in plasmid pBR322 against scission induced by Fenton-mediated hydroxyl radical. The preincubation of PC12 cells with the EPS prior to H2O2 exposure increased the cell survival and glutathione (GSH level and catalase (CAT activities, and decreased the level of malondialdehyde (MDA and lactate dehydrogenase (LDH activity in a dose-dependent manner, suggesting a pronounced protective effect against H2O2-induced cytotoxicity. Our study indicated that the EPS could be useful for preventing oxidative DNA damage and cellular oxidation in pharmaceutical and food industries.

  4. Catalytic properties of Sepharose-bound L-alanine dehydrogenase from Bacillus cereus.

    Science.gov (United States)

    Mureşan, L; Vancea, D; Presecan, E; Porumb, H; Lascu, I; Oargă, M; Matinca, D; Abrudan, I; Bârzu, O

    1983-02-15

    (1) L-Alanine dehydrogenase from Bacillus cereus was purified by a two-step chromatographic procedure involving Cibacron-Blue 3G-A Sepharose 4B-CL, and Sepharose 6B-CL, and immobilized on CNBr-activated Sepharose 4B. (2) Following immobilization via two of the six subunits, L-alanine dehydrogenase retained 66% of the specific activity of the soluble enzyme. The affinity of the immobilized enzyme for NH4+, pyruvate and L-alanine, was not different to that of the soluble form. The Km of the Sepharose-bound L-alanine dehydrogenase for pyridine coenzymes was 6-8-times higher than in the soluble case. (3) The stability of L-alanine dehydrogenase towards urea or thermal denaturation was increased by immobilization. (4) The incubation at 37 degrees C for 24 h of the immobilized L-alanine dehydrogenase with 3 M NH4Cl/NH4OH buffer (pH 9) released 70% of the enzyme. The specific activity and the affinity of the 'solubilized' L-alanine dehydrogenase for the pyridine coenzymes was the same as that obtained with the original, soluble L-alanine dehydrogenase. PMID:6404304

  5. Purification and Characterization of a Nonylphenol (NP)-degrading Enzyme from Bacillus cereus.Frankland

    Institute of Scientific and Technical Information of China (English)

    YANG Ge; ZHANG Ying; BAI Yanfen

    2011-01-01

    An extracellular NP-degrading enzyme secreted by Bacillus cereus.Frankland was purified to homogeneity by a combination of ammonium sulfate precipitation,Phenyl-Sepharose hydrophobic-interaction chromatography and DEAE anion-exchange chromatography.On SDS(sodium dodecyl sulfate)-polyacrylamide gel electrophoresis analysis,the purified enzyme showed a relative molecular mass of 58.3 kDa.The depolymerzation of subunits was accompanied with the loss of NP-degrading enzyme activity,and removing denaturing factors by dialysis could restore the dimer structure and enzymatic activity.The enzyme had an isoelectric point of 5.5 and an optimal temperature of 60℃,and was the most active at pH 6.0.The enzymatic activity was stable at pH 4-8 and inhibited by Cu2+.TenN-terminal amino acids were determined to be ASVNSIKIGY,demonstrating that the purified enzyme was a novel one.The hydrolysis pattern of the purified enzyme indicated that the NP-degrading enzyme was an endo NP-degrading enzyme.The extraordinary thermo-stability provided the enzyme with a good prospect to be used as a new tool for clean-production process for textile industry.

  6. Investigation into the mechanism of the Bacillus cereus phosphonoacetaldehyde hydrolase enzyme

    International Nuclear Information System (INIS)

    The enzyme phosphonoacetaldehyde hydrolase, isolated from Bacillus cereus, catalyzes the dephosphonylation of phosphonoacetaldehyde yielding acetaldehyde and phosphate. We determined that the enzyme was inactivated when it was incubated with substrate or acetaldehyde in the presence of NaBH4. The chemical modification was determined to be specific for a single lysine residue by the use of active site radiolabeling methodologies. Phosphonatase was incubated with [3H]-NaBH4 and phosphonoacetaldehyde, [14C]-acetaldehyde/NaBH4, and with [C2-3H]-phosphonoacetaldehyde/NaBH4 which yielded radiolabeled enzyme. The latter of these experiments yielded the most specifically labeled phosphonatase as determined by RP-HPLC separation of the peptides generated by a tryptic digest of the enzyme. The active site peptide was purified to homogeneity and its primary structure determined. var-epsilon-N-Ethyl-L-lysine was identified as the radiolabeled component of the sequence. Acetonyl phosphonate was able to protect phosphonatase from phosphonoacetaldehyde/NaBH4 induced inactivation which suggests that the lysine is in the active site

  7. Structural basis of the substrate specificity of Bacillus cereus adenosine phosphorylase

    Energy Technology Data Exchange (ETDEWEB)

    Dessanti, Paola; Zhang, Yang; Allegrini, Simone; Tozzi, Maria Grazia; Sgarrella, Francesco; Ealick, Steven E. (Cornell); (Sassari); (Pisa)

    2012-10-08

    Purine nucleoside phosphorylases catalyze the phosphorolytic cleavage of the glycosidic bond of purine (2{prime}-deoxy)nucleosides, generating the corresponding free base and (2{prime}-deoxy)ribose 1-phosphate. Two classes of PNPs have been identified: homotrimers specific for 6-oxopurines and homohexamers that accept both 6-oxopurines and 6-aminopurines. Bacillus cereus adenosine phosphorylase (AdoP) is a hexameric PNP; however, it is highly specific for 6-aminopurines. To investigate the structural basis for the unique substrate specificity of AdoP, the active-site mutant D204N was prepared and kinetically characterized and the structures of the wild-type protein and the D204N mutant complexed with adenosine and sulfate or with inosine and sulfate were determined at high resolution (1.2-1.4 {angstrom}). AdoP interacts directly with the preferred substrate through a hydrogen-bond donation from the catalytically important residue Asp204 to N7 of the purine base. Comparison with Escherichia coli PNP revealed a more optimal orientation of Asp204 towards N7 of adenosine and a more closed active site. When inosine is bound, two water molecules are interposed between Asp204 and the N7 and O6 atoms of the nucleoside, thus allowing the enzyme to find alternative but less efficient ways to stabilize the transition state. The mutation of Asp204 to asparagine led to a significant decrease in catalytic efficiency for adenosine without affecting the efficiency of inosine cleavage.

  8. Crystallization and preliminary X-ray analysis of a phosphopentomutase from Bacillus cereus

    International Nuclear Information System (INIS)

    Two crystal forms of an Mn2+-dependent phosphopentomutase were identified from chemically distinct conditions by sparse-matrix screening with and without the inclusion of 50 mM Mn2+. The crystals identified in the presence of Mn2+ were of dramatically better diffraction quality than those identified in the absence of added Mn2+. Phosphopentomutases (PPMs) interconvert d-ribose 5-phosphate and α-d-ribose 1-phosphate to link glucose and nucleotide metabolism. PPM from Bacillus cereus was overexpressed in Escherichia coli, purified to homogeneity and crystallized. Bacterial PPMs are predicted to contain a di-metal reaction center, but the catalytically relevant metal has not previously been identified. Sparse-matrix crystallization screening was performed in the presence or absence of 50 mM MnCl2. This strategy resulted in the formation of two crystal forms from two chemically distinct conditions. The crystals that formed with 50 mM MnCl2 were more easily manipulated and diffracted to higher resolution. These results suggest that even if the catalytically relevant metal is not known, the crystallization of putative metalloproteins may still benefit from supplementation of the crystallization screens with potential catalytic metals

  9. Nanosensors having dipicolinic acid imprinted nanoshell for Bacillus cereus spores detection

    International Nuclear Information System (INIS)

    Molecular imprinted polymers (MIPs) as a recognition element for sensors are increasingly of interest and MIP nanoclusters have started to appear in the literature. In this study, we have proposed a novel thiol ligand-capping method with polymerizable methacryloylamido-cysteine (MAC) attached to gold-silver nanoclusters, reminiscent of a self-assembled monolayer and have reconstructed surface shell by synthetic host polymers based on molecular imprinting method for recognition. In this method, methacryloylamidoantipyrine-terbium ((MAAP)2-Tb(III)) has been used as a new metal-chelating monomer via metal coordination-chelation interactions and dipicolinic acid (DPA) which is main participant of Bacillus cereus spores used as a model. Nanoshell sensors with templates give a cavity that is selective for DPA. The DPA can simultaneously chelate to Tb(III) metal ion and fit into the shape-selective cavity. Thus, the interaction between Tb(III) ion and free coordination spheres has an effect on the binding ability of the gold-silver nanoclusters nanosensor. The binding affinity of the DPA imprinted nanoclusters has been investigated by using the Langmuir and Scatchard methods, and the respective affinity constants (Kaffinity) determined were found to be 1.43 x 104 and 9.1 x 106 mol L-1.

  10. Nanosensors having dipicolinic acid imprinted nanoshell for Bacillus cereus spores detection

    Energy Technology Data Exchange (ETDEWEB)

    Gueltekin, Aytac [Trakya University, Department of Chemistry (Turkey); Ersoez, Arzu [Anadolu University, Department of Chemistry, Faculty of Science, Yunusemre Campus (Turkey); Sarioezlue, Nalan Yilmaz [Anadolu University, Department of Biology (Turkey); Denizli, Adil [Hacettepe University, Department of Chemistry (Turkey); Say, Ridvan, E-mail: rsay@anadolu.edu.t [Anadolu University, Department of Chemistry, Faculty of Science, Yunusemre Campus (Turkey)

    2010-08-15

    Molecular imprinted polymers (MIPs) as a recognition element for sensors are increasingly of interest and MIP nanoclusters have started to appear in the literature. In this study, we have proposed a novel thiol ligand-capping method with polymerizable methacryloylamido-cysteine (MAC) attached to gold-silver nanoclusters, reminiscent of a self-assembled monolayer and have reconstructed surface shell by synthetic host polymers based on molecular imprinting method for recognition. In this method, methacryloylamidoantipyrine-terbium ((MAAP){sub 2}-Tb(III)) has been used as a new metal-chelating monomer via metal coordination-chelation interactions and dipicolinic acid (DPA) which is main participant of Bacillus cereus spores used as a model. Nanoshell sensors with templates give a cavity that is selective for DPA. The DPA can simultaneously chelate to Tb(III) metal ion and fit into the shape-selective cavity. Thus, the interaction between Tb(III) ion and free coordination spheres has an effect on the binding ability of the gold-silver nanoclusters nanosensor. The binding affinity of the DPA imprinted nanoclusters has been investigated by using the Langmuir and Scatchard methods, and the respective affinity constants (K{sub affinity}) determined were found to be 1.43 x 10{sup 4} and 9.1 x 10{sup 6} mol L{sup -1}.

  11. Representative of the municipality

    International Nuclear Information System (INIS)

    Full text of publication follows. The decommissioning of the Vandellos-I nuclear power plant was a big challenge for the host community of Vandellos i l'Hospitalet de l'Infant and the close-by region. Closing down of the facility resulted in a rise of unemployment and a decrease of municipal income. The public was concerned with three issues: safety, transparency and information about the decommissioning, and economic future. Therefore, from the very beginning, municipal governments entered into negotiations with ENRESA on socio-economic benefits, including local employment in dismantling activities, and other types of financial and non-financial compensation. The ADE business association, i.e. a network of business organisations was created that guided the allotment of work to local firms. To satisfy public demand, local municipalities focused on the triad of safety, dialogue and local development, considered the three 'pillars of trust'. A Municipal Monitoring Commission was created, made up of representatives of affected municipalities, the regional government, the ADE business association, trade unions, the local university, the NPP management and ENRESA to monitor the dismantling process and regularly inform the local public. Items that were handled by this Commission included: - Work process monitoring. - Workers. - Materials Control. - Conventional and radioactive or contaminated waste management. - Emanation waste management (liquid and gas) - Safety (training and accidents). - Surveillance (radiological and environmental: dust, noise). - Effects. - Fulfillment of agreed conditions. A number of communication tools and channels were used, e.g., public information meetings, an information centre, the municipal magazine, the municipal radio station, and meetings with representatives of the local press. Particularly innovative was the idea to ask academics from the University of Tarragona to help with 'translating' technical information into language that could

  12. Ocorrência de Bacillus cereus em leite integral e capacidade enterotoxigênica das cepas isoladas Occurrence of Bacillus cereus in Whole milk and enterotoxigenic potential of the isolated strains

    Directory of Open Access Journals (Sweden)

    N.C.M. Rezende-Lago

    2007-12-01

    Full Text Available Pesquisaram-se a presença de Bacillus cereus e a produção de enterotoxinas produzidas por esses microrganismos em 120 amostras de diversos tipos de leite. Bacillus cereus foi isolado e identificado em 22 (73,3%, 15 (50,0%, 29 (96,7% e quatro (13,3% amostras de leite em pó, cru, pasteurizado e UAT (longa vida, respectivamente. Para a detecção de enterotoxinas pela técnica da alça ligada de coelho, foram positivos, respectivamente, três (13,6%, um (7,1% e 10 (35,7% microrganismos isolados das amostras de leite em pó, leite cru e leite pasteurizado. Pelo teste de aumento de permeabilidade vascular, dois (9,1%, um (7,1%, um (3,6% e um (4,0% microrganismos isolados de leite em pó, cru, pasteurizado e UAT apresentaram-se enterotoxigênicos, respectivamente. O uso da técnica de aglutinação passiva em látex demonstrou a produção da toxina diarréica por três (33,3%, sete (63,6%, quatro (30,8% e oito (80,0% microrganismos isolados, respectivamente, de leite em pó, cru, pasteurizado e UAT. Os resultados indicam um risco potencial, podendo colocar em risco a saúde dos consumidores desses produtos.A hundred and twenty samples of different types of milk were examined to the presence of Bacillus cereus and the enterotoxigenic potential of the isolated strains. Bacillus cereus was isolated and identified in 22 (73.0%, 15 (50.0%, 29 (96.7% and four (13.3% samples of powder, raw, pasteurized and UHT milk, respectively. The enterotoxigenicity detection using the rabbit ileal loop assay showed positive, respectively, three (13.6%, one (7.1% and 10 (35.7% isolated strains from powder, raw and pasteurized milk. Using vascular permeability activity assay two (9.1%, one (7.1%, one (3.6% and one (4.0% isolated strains from powder, raw, pasteurized and UHT milk were positive, respectively. The reversed passive latex agglutination test showed diarrheal toxin production by three (33.3%, seven (63.6%, four (30.8% and eight (80.0% strains isolated from

  13. Puerto Rico and Florida manatees represent genetically distinct groups

    Science.gov (United States)

    Hunter, Margaret E.; Mignucci-Giannoni, Antonio A.; Tucker, Kimberly Pause; King, Timothy L.; Bonde, Robert K.; Gray, Brian A.; McGuire, Peter M.

    2012-01-01

    The West Indian manatee (Trichechus manatus) populations in Florida (T. m. latirostris) and Puerto Rico (T. m. manatus) are considered distinct subspecies and are listed together as endangered under the United States Endangered Species Act. Sustained management and conservation efforts for the Florida subspecies have led to the suggested reclassification of the species to a threatened or delisted status. However, the two populations are geographically distant, morphologically distinct, and habitat degradation and boat strikes continue to threaten the Puerto Rico population. Here, 15 microsatellite markers and mitochondrial control region sequences were used to determine the relatedness of the two populations and investigate the genetic diversity and phylogeographic organization of the Puerto Rico population. Highly divergent allele frequencies were identified between Florida and Puerto Rico using microsatellite (F ST = 0.16; R ST = 0.12 (P ST = 0.66; Φ ST = 0.50 (P E = 0.45; NA = 3.9), were similar, but lower than those previously identified in Florida (HE = 0.48, NA = 4.8). Within Puerto Rico, the mitochondrial genetic diversity values (π = 0.001; h = 0.49) were slightly lower than those previously reported (π = 0.002; h = 0.54) and strong phylogeographic structure was identified (F ST global = 0.82; Φ ST global = 0.78 (P < 0.001)). The genetic division with Florida, low diversity, small population size (N = 250), and distinct threats and habitat emphasize the need for separate protections in Puerto Rico. Conservation efforts including threat mitigation, migration corridors, and protection of subpopulations could lead to improved genetic variation in the endangered Puerto Rico manatee population.

  14. Representing objects, relations, and sequences.

    Science.gov (United States)

    Gallant, Stephen I; Okaywe, T Wendy

    2013-08-01

    Vector symbolic architectures (VSAs) are high-dimensional vector representations of objects (e.g., words, image parts), relations (e.g., sentence structures), and sequences for use with machine learning algorithms. They consist of a vector addition operator for representing a collection of unordered objects, a binding operator for associating groups of objects, and a methodology for encoding complex structures. We first develop constraints that machine learning imposes on VSAs; for example, similar structures must be represented by similar vectors. The constraints suggest that current VSAs should represent phrases ("The smart Brazilian girl") by binding sums of terms, in addition to simply binding the terms directly. We show that matrix multiplication can be used as the binding operator for a VSA, and that matrix elements can be chosen at random. A consequence for living systems is that binding is mathematically possible without the need to specify, in advance, precise neuron-to-neuron connection properties for large numbers of synapses. A VSA that incorporates these ideas, Matrix Binding of Additive Terms (MBAT), is described that satisfies all constraints. With respect to machine learning, for some types of problems appropriate VSA representations permit us to prove learnability rather than relying on simulations. We also propose dividing machine (and neural) learning and representation into three stages, with differing roles for learning in each stage. For neural modeling, we give representational reasons for nervous systems to have many recurrent connections, as well as for the importance of phrases in language processing. Sizing simulations and analyses suggest that VSAs in general, and MBAT in particular, are ready for real-world applications. PMID:23607563

  15. HIDROFOBICIDADE DE RIBOTIPOS DE BACILLUS CEREUS ISOLADOS DE INDÚSTRIA DE LATICÍNIOS

    Directory of Open Access Journals (Sweden)

    Emiliane Andrade ARAÚJO

    2010-03-01

    Full Text Available

    A contaminação de superfícies por microrganismos deterioradores e patogênicos é causa de preocupação na indústria de alimentos. Desenvolvimento de biofilmes em ambientes de processamento de alimentos resulta na deterioração do produto e em possíveis riscos para a saúde pública, além de criar sérios problemas nas operações de processamento do fl uido. A adesão da bactéria à superfície é um dos primeiros passos para a formação do biofilme e propriedades físico-químicas da interface bacteriana infl uenciam o processo de adesão microbiana e, consequentemente, os procedimentos operacionais de higienização. A estrutura do biofilme e as características fisiológicas do microrganismo podem conferir resistência aos agentes antimicrobianos, como por exemplo, aos sanitizantes usados no procedimento de higienização. Dentre os fatores que infl uenciam o processo de adesão, as características de hidrofobicidade do microrganismo e da superfície apresentam grande importância nos mecanismos de adesão. As técnicas da medição do ângulo de contato e da coluna de interação hidrofóbica, para determinação da hidrofobicidade de superfícies de ribotipos de Bacillus cereus isolados de indústria de laticínios, foram avaliadas. Observou-se que as quatro superfícies dos ribotipos avaliados apresentaram a mesma classificação quanto à hidrofobicidade tanto pela medida do ângulo de contato com a água quanto pela determinação da energia livre de interação hidrofóbica (ΔGsas TOT. Três ribotipos foram considerados hidrofílicos e um hidrofóbico. Já a técnica da coluna de interação hidrofóbica não mostrou diferença (p>0,05 no percentual de células retidas na coluna, sugerindo que as superfícies dos ribotipos apresentam as mesmas características quanto à hidrofobicidade. Os resultados indicam que a técnica da medição do ângulo de contato é a mais indicada para avaliar a

  16. Radiosensibilisation of bacteria on beef minced by essential oils with special reference to the spores of Bacillus cereus ATCC 7004

    International Nuclear Information System (INIS)

    The radiosensitization of Bacillus Cereus ATCC 7004 spores was evaluated in the presence of thymol, thyme, D-L menthol, trans-cinnamaldehyde and eugenol in ground beef. Meat cattle minced (5 % fat) was inoculated with spores of Bacillus Cereus (10 5 - 10 6 CFU / g), and each compound was added separately at various concentrations. The antimicrobial potential was evaluated in unirradiated meat by determining the MIC in percentage (wt / wt) after 24 h of storage at 4± 1C. Results showed that the best antimicrobial compound was the trans-cinnamaldehyde with MIC of 1.47%, wt/wt. In presence of cinnamaldehyde, the addition of sodium pyrophosphate decahydrate (0.1%, wt/wt) increased significantly (p < 0.05) the relative sensitivity of Bacillus Cereus spores 2 times. However, the presence of ascorbic acid in the media reduced significantly (p < 0.05) the radiosensitivity of bacteria. The combined effect of gamma irradiation in presence of cinnamaldehyde, added with ascorbic acid or sodium pyrophosphate decahydrate, on the microbiological and physico-chemical characteristic of meat samples was evaluated at 2 kGy under air. The use of the active compounds with the irradiation reduced significantly (p < 0.05) the count of total bacteria with a concomitant effect in the extension periods of shelf life. The addition of the cinnamaldehyde induced a significant reduction (p < 0.05) in TVN and free amino acids of irradiated samples. In presence of ascorbic acid the thiobarbituric acid-reactive substances (TBARS) concentration was significantly reduced (P...0.05). A significant reduction (p < 0.05) of a* and C* of color values and a significant increase (p < 0.05 ) of b* value were obtained for the samples treated by the cinnamaldehyde. The application of bioactive films for the immobilization of the essential oils is a good alternate to check their stability during storage time. (Author). 155 refs

  17. Molecular Differences between a Mutase and a Phosphatase: Investigations of the Activation Step in Bacillus cereus Phosphopentomutase

    Energy Technology Data Exchange (ETDEWEB)

    Iverson, T.M.; Panosian, Timothy D.; Birmingham, William R.; Nannemann, David P.; Bachmann, Brian O. (Vanderbilt)

    2012-05-09

    Prokaryotic phosphopentomutases (PPMs) are di-Mn{sup 2+} enzymes that catalyze the interconversion of {alpha}-D-ribose 5-phosphate and {alpha}-D-ribose 1-phosphate at an active site located between two independently folded domains. These prokaryotic PPMs belong to the alkaline phosphatase superfamily, but previous studies of Bacillus cereus PPM suggested adaptations of the conserved alkaline phosphatase catalytic cycle. Notably, B. cereus PPM engages substrates when the active site nucleophile, Thr-85, is phosphorylated. Further, the phosphoenzyme is stable throughout purification and crystallization. In contrast, alkaline phosphatase engages substrates when the active site nucleophile is dephosphorylated, and the phosphoenzyme reaction intermediate is only stably trapped in a catalytically compromised enzyme. Studies were undertaken to understand the divergence of these mechanisms. Crystallographic and biochemical investigations of the PPM{sup T85E} phosphomimetic variant and the neutral corollary PPM{sup T85Q} determined that the side chain of Lys-240 underwent a change in conformation in response to active site charge, which modestly influenced the affinity for the small molecule activator {alpha}-D-glucose 1,6-bisphosphate. More strikingly, the structure of unphosphorylated B. cereus PPM revealed a dramatic change in the interdomain angle and a new hydrogen bonding interaction between the side chain of Asp-156 and the active site nucleophile, Thr-85. This hydrogen bonding interaction is predicted to align and activate Thr-85 for nucleophilic addition to {alpha}-D-glucose 1,6-bisphosphate, favoring the observed equilibrium phosphorylated state. Indeed, phosphorylation of Thr-85 is severely impaired in the PPM{sup D156A} variant even under stringent activation conditions. These results permit a proposal for activation of PPM and explain some of the essential features that distinguish between the catalytic cycles of PPM and alkaline phosphatase.

  18. Reconstitution of Bacillus cereus 5/B/6 metallo-[beta]-lactamase activity with copper

    Energy Technology Data Exchange (ETDEWEB)

    Hilliard, N.P.; Shaw, R.W. (Texas Tech Univ., Lubbock (United States))

    1992-01-01

    Pathogenic bacteria become resistant to [beta]-lactam antibiotics such as penicillins and cephalosporins through the production of enzymes called [beta]-lactamases. The authors have successfully reconstituted the enzymatic activity of the metallo-[beta]-lactamase of Bacillus cereus 5/B/6 purified from an E. coli expression vector system by the addition of Cu(II) to the apoenzyme. This is the first report that copper supports catalytic activity in this enzyme. Maximal activity of the copper-reconstituted enzyme was achieved by a careful addition of a stoichiometric amount of CuSO[sub 4] to 200 [mu]M apoenzyme. Using either benzylpenicillin or cephalosporin C as the substrate, reconstitution of the activity by addition of copper to the apoenzyme resulted in the recovery of approximately 35% of the control activity of the native Zn(II) enzyme. In agreement with previous reports, in the presence of excess Cu(II), the preparation did not possess measurable catalytic activity. Electronic spectra of the copper-reconstituted enzyme displayed adsorption maxima at 394, 698 and 1,022 nm with extinction coefficients of 2,656, 55 and < 3 M[sup [minus]1]cm[sup [minus]1] respectively. Circular dichorism spectra in the ultraviolent region (UVCD) of the copper-reconstituted enzyme were identical with those of the native Zn(II) enzyme. Addition of excess cephalosporin C to the copper-reconstituted enzyme caused a decrease of about 50% of the absorbance of the 394 nm band and the formation of a new feature at 350 nm.

  19. Characterization of Pullulanase Type II from Bacillus cereus H1.5

    Directory of Open Access Journals (Sweden)

    Hii Siew Ling

    2009-01-01

    Full Text Available Problem statement: Pullulanase is one of the important enzymes in starch industry. Search for the pullulanase with distinct features, possibly from easily grown bacterium, is of interest for industrial applications Approach: The extracellular pullulanase produced by Bacillus cereus HI.5 was purified by chromatographic method of DEAE-Sepharose, followed by Superdex gel filtration. The enzyme was characterized in terms of the optimal pH and temperature for activity as well as substrate specificity. Results: The enzyme showed optimal activity at 55°C and pH 6.0. The thermostability and the thermoactivity of the enzyme were increased considerably in the presence of Ca2+. In the present of 2 mM Ca2+, the enzyme had half-life duration of more than 2 h at 50°C. Almost all metal ions had a strong inhibitory effect, except Ca2+ and Mn2+. The Ca2+ had a very strong stimulating effect on the enzyme, increasing its activity by 170%. The enzyme was activated by 2-mercaptoethanol and dithiothreitol, where as N-bromosuccinimide and Schardinger dextrins were inhibitors, suggesting that tryptophan and thiol residues may be important for the activity. The apparent Km and Vmax value for pullulan was 1.1 mg mL-1 and 0.275 µmol min-1, respectively. A relative substrate specificity for hydrolysis of pullulan, amylopectin and soluble starch by this pullulanase was 100, 28.5 and 20.4%, respectively. Conclusion: The enzyme was able to attack specifically the α-1,6 linkages in pullulan to generate maltotriose as the major end product, as well as the α-1,4 linkages in amylopectin and soluble starch leading to the formation of a mixture of maltose and glucose and therefore be classified as a type II pullulanase or an amylopullulanase.

  20. Bacillus cereus cytotoxins Hbl, Nhe and CytK are secreted via the Sec translocation pathway

    Directory of Open Access Journals (Sweden)

    Lindbäck Toril

    2010-11-01

    Full Text Available Abstract Background Bacillus cereus and the closely related Bacillus thuringiensis are Gram positive opportunistic pathogens that may cause food poisoning, and the three secreted pore-forming cytotoxins Hbl, Nhe and CytK have been implicated as the causative agents of diarrhoeal disease. It has been proposed that the Hbl toxin is secreted using the flagellar export apparatus (FEA despite the presence of Sec-type signal peptides. As protein secretion is of key importance in virulence of a microorganism, the mechanisms by which these toxins are secreted were further investigated. Results Sec-type signal peptides were identified in all toxin components, and secretion of Hbl component B was shown to be dependent on an intact Sec-type signal peptide sequence. Further indication that secretion of Hbl, Nhe and CytK is dependent on the Sec translocation pathway, the main pathway on which bacterial secretion relies, was suggested by the observed intracellular accumulation and reduced secretion of the toxins in cultures supplemented with the SecA inhibitor sodium azide. Although a FEA deficient strain (a flhA mutant showed reduced toxin expression and reduced cytotoxicity, it readily secreted overexpressed Hbl B, showing that the FEA is not required for Hbl secretion. Thus, the concurrent lack of flagella and reduced toxin secretion in the FEA deficient strain may point towards the presence of a regulatory link between motility and virulence genes, rather than FEA-dependent toxin secretion. Conclusions The Hbl, Nhe and CytK toxins appear to be secreted using the Sec pathway, and the reduced Hbl expression of a FEA deficient strain was shown not to be due to a secretion defect.

  1. Gold nanoparticles having dipicolinic acid imprinted nanoshell for Bacillus cereus spores recognition

    Energy Technology Data Exchange (ETDEWEB)

    Gueltekin, Aytac [Department of Chemistry, Trakya University, Edirne (Turkey); Ersoez, Arzu; Huer, Deniz [Department of Chemistry, Anadolu University, Eskisehir (Turkey); Sarioezlue, Nalan Yilmaz [Department of Biology, Anadolu University, Eskisehir (Turkey); Denizli, Adil [Department of Chemistry, Hacettepe University, Ankara (Turkey); Say, Ridvan, E-mail: rsay@anadolu.edu.tr [Department of Chemistry, Anadolu University, Eskisehir (Turkey); BIBAM (Plant, Drug and Scientific Research Center) Anadolu University (Turkey)

    2009-10-15

    Taking into account the recognition element for sensors linked to molecular imprinted polymers (MIPs), a proliferation of interest has been witnessed by those who are interested in this subject. Indeed, MIP nanoparticles are theme which recently has come to light in the literature. In this study, we have proposed a novel thiol ligand-capping method with polymerizable methacryloylamidocysteine (MAC) attached to gold nanoparticles, reminiscent of a self-assembled monolayer. Furthermore, a surface shell by synthetic host polymers based on molecular imprinting method for recognition has been reconstructed. In this method, methacryloyl iminodiacetic acid-chrome (MAIDA-Cr(III)) has been used as a new metal-chelating monomer via metal coordination-chelation interactions and dipicolinic acid (DPA) which is the main participant of Bacillus cereus spores has been used as a template. Nanoshell sensors with templates produce a cavity that is selective for DPA. The DPA can simultaneously chelate to Cr(III) metal ion and fit into the shape-selective cavity. Thus, the interaction between Cr(III) ion and free coordination spheres has an effect on the binding ability of the gold nanoparticles nanosensor. The interactions between DPA and MIP particles were studied observing fluorescence measurements. DPA addition caused significant decreases in fluorescence intensity because they induced photoluminescence emission from Au nanoparticles through the specific binding to the recognition sites of the crosslinked nanoshell polymer matrix. The binding affinity of the DPA imprinted nanoparticles has been explored by using the Langmuir and Scatchard methods and the analysis of the quenching results has been performed in terms of the Stern-Volmer equation.

  2. Gold nanoparticles having dipicolinic acid imprinted nanoshell for Bacillus cereus spores recognition

    International Nuclear Information System (INIS)

    Taking into account the recognition element for sensors linked to molecular imprinted polymers (MIPs), a proliferation of interest has been witnessed by those who are interested in this subject. Indeed, MIP nanoparticles are theme which recently has come to light in the literature. In this study, we have proposed a novel thiol ligand-capping method with polymerizable methacryloylamidocysteine (MAC) attached to gold nanoparticles, reminiscent of a self-assembled monolayer. Furthermore, a surface shell by synthetic host polymers based on molecular imprinting method for recognition has been reconstructed. In this method, methacryloyl iminodiacetic acid-chrome (MAIDA-Cr(III)) has been used as a new metal-chelating monomer via metal coordination-chelation interactions and dipicolinic acid (DPA) which is the main participant of Bacillus cereus spores has been used as a template. Nanoshell sensors with templates produce a cavity that is selective for DPA. The DPA can simultaneously chelate to Cr(III) metal ion and fit into the shape-selective cavity. Thus, the interaction between Cr(III) ion and free coordination spheres has an effect on the binding ability of the gold nanoparticles nanosensor. The interactions between DPA and MIP particles were studied observing fluorescence measurements. DPA addition caused significant decreases in fluorescence intensity because they induced photoluminescence emission from Au nanoparticles through the specific binding to the recognition sites of the crosslinked nanoshell polymer matrix. The binding affinity of the DPA imprinted nanoparticles has been explored by using the Langmuir and Scatchard methods and the analysis of the quenching results has been performed in terms of the Stern-Volmer equation.

  3. Gold nanoparticles having dipicolinic acid imprinted nanoshell for Bacillus cereus spores recognition

    Science.gov (United States)

    Gültekin, Aytaç; Ersöz, Arzu; Hür, Deniz; Sarıözlü, Nalan Yılmaz; Denizli, Adil; Say, Rıdvan

    2009-10-01

    Taking into account the recognition element for sensors linked to molecular imprinted polymers (MIPs), a proliferation of interest has been witnessed by those who are interested in this subject. Indeed, MIP nanoparticles are theme which recently has come to light in the literature. In this study, we have proposed a novel thiol ligand-capping method with polymerizable methacryloylamidocysteine (MAC) attached to gold nanoparticles, reminiscent of a self-assembled monolayer. Furthermore, a surface shell by synthetic host polymers based on molecular imprinting method for recognition has been reconstructed. In this method, methacryloyl iminodiacetic acid-chrome (MAIDA-Cr(III)) has been used as a new metal-chelating monomer via metal coordination-chelation interactions and dipicolinic acid (DPA) which is the main participant of Bacillus cereus spores has been used as a template. Nanoshell sensors with templates produce a cavity that is selective for DPA. The DPA can simultaneously chelate to Cr(III) metal ion and fit into the shape-selective cavity. Thus, the interaction between Cr(III) ion and free coordination spheres has an effect on the binding ability of the gold nanoparticles nanosensor. The interactions between DPA and MIP particles were studied observing fluorescence measurements. DPA addition caused significant decreases in fluorescence intensity because they induced photoluminescence emission from Au nanoparticles through the specific binding to the recognition sites of the crosslinked nanoshell polymer matrix. The binding affinity of the DPA imprinted nanoparticles has been explored by using the Langmuir and Scatchard methods and the analysis of the quenching results has been performed in terms of the Stern-Volmer equation.

  4. Prevalence of Bacillus cereus and associated risk factors in Chinese-style fried rice available in the city of Colombo, Sri Lanka.

    Science.gov (United States)

    Perera, Manosha Lakmali; Ranasinghe, Gerard Ranjan

    2012-02-01

    The present study aimed to assess the prevalence of Bacillus cereus and its associated risk factors in Chinese-style fried rice available in Colombo city. In 200 samples of fried rice the prevalence of B. cereus was 56%. The prevalence by variety of fried rice was chicken (20.0%), vegetable (18.0%), seafood (10.0%), egg (5.0%), mixed (2.0%), and beef (1.0%). Of analyzed samples, 28 (14%) had colony counts >10(6) colony forming units per gram (cfu/g), the infectious dose for B. cereus food borne outbreaks. Occurrence of >10(6) cfu/g of B. cereus were associated with storage of boiled rice at room temperature (p=0.030), >4 hours of storage at room temperature (p=0.042) and cooking frequency of more than once per dining session (p=0.017). The type of rice and the quantity boiled per day were not independent risk factors for high B. cereus counts. Majority of B. cereus isolates (53.7%) in this study were not typable. The serotypes observed included H15 (14.3%), H19 (14.3%), and H20 (10.7%). These serotypes are known to be associated with both emetic and diarrheal syndromes. All isolates were sensitive to ciprofloxacin (100%), erythromycin (100%), gentamicin (100%), chloramphenicol (100%), and amikacin (100%) whereas 100% resistance was observed for penicillin with minimal inhibitory concentration range of 32-256 μg/mL. PMID:22085218

  5. The Exosporium of B.cereus Contains a Binding Site for gC1qR/p33: Implication in Spore Attachment and/or Entry.

    Energy Technology Data Exchange (ETDEWEB)

    GHEBREHIWET,B.; TANTRAL, L.; TITMUS, M.A.; PANESSA-WARREN, B.J.; TORTORA, G.T.; WONG, S.S.; WARREN, J.B.

    2008-01-01

    B. cereus, is a member of a genus of aerobic, gram-positive, spore-forming rod-like bacilli, which includes the deadly, B. anthracis. Preliminary experiments have shown that gC1qR binds to B.cereus spores that have been attached to microtiter plates. The present studies were therefore undertaken, to examine if cell surface gC1qR plays a role in B.cereus spore attachment and/or entry. Monolayers of human colon carcinoma (Caco-2) and lung cells were grown to confluency on 6 mm coverslips in shell vials with gentle swirling in a shaker incubator. Then, 2 {micro}l of a suspension of strain SB460 B.cereus spores (3x10{sup 8}/ml, in sterile water), were added and incubated (1-4 h; 36{sup 0} C) in the presence or absence of anti-gC1qR mAb-carbon nanoloops. Examination of these cells by EM revealed that: (1) When B. cereus endospores contacted the apical Caco-2 cell surface, or lung cells, gClqR was simultaneously detectable, indicating upregulation of the molecule. (2) In areas showing spore contact with the cell surface, gClqR expression was often adjacent to the spores in association with microvilli (Caco-2 cells) or cytoskeletal projections (lung cells). (3) Furthermore, the exosporia of the activated and germinating spores were often decorated with mAb-nanoloops. These observations were further corroborated by experiments in which B.cereus spores were readily taken up by monocytes and neutrophils, and this uptake was partially inhibited by mAb 60.11, which recognizes the C1q binding site on gC1qR. Taken together, the data suggest a role, for gC1qR at least in the initial stages of spore attachment and/or entry.

  6. Biocontrol of Aspergillus species on peanut kernels by antifungal diketopiperazine producing Bacillus cereus associated with entomopathogenic nematode.

    Directory of Open Access Journals (Sweden)

    Sasidharan Nishanth Kumar

    Full Text Available The rhabditid entomopathogenic nematode associated Bacillus cereus and the antifungal compounds produced by this bacterium were evaluated for their activity in reducing postharvest decay of peanut kernels caused by Aspergillus species in in vitro and in vivo tests. The results showed that B. cereus had a significant effect on biocontrol effectiveness in in vitro and in vivo conditions. The antifungal compounds produced by the B. cereus were purified using silica gel column chromatography and their structure was elucidated using extensive spectral analyses. The compounds were identified as diketopiperazines (DKPs [cyclo-(L-Pro-Gly, cyclo(L-Tyr-L-Tyr, cyclo-(L-Phe-Gly and cyclo(4-hydroxy-L-Pro-L-Trp]. The antifungal activities of diketopiperazines were studied against five Aspergillus species and best MIC of 2 µg/ml was recorded against A. flavus by cyclo(4-hydroxy-L-Pro-L-Trp. To investigate the potential application of cyclo(4-hydroxy-L-Pro-L-Trp to eliminate fungal spoilage in food and feed, peanut kernels was used as a food model system. White mycelia and dark/pale green spores of Aspergillus species were observed in the control peanut kernels after 2 days incubation. However the fungal growth was not observed in peanut kernels treated with cyclo(4-hydroxy-L-Pro-L-Trp. The cyclo(4-hydroxy-L-Pro-L-Trp was nontoxic to two normal cell lines [fore skin (FS normal fibroblast and African green monkey kidney (VERO] up to 200 µg/ml in MTT assay. Thus the cyclo(4-hydroxy-L-Pro-L-Trp identified in this study may be a promising alternative to chemical preservatives as a potential biopreservative agent which prevent fungal growth in food and feed. To the best of our knowledge, this is the first report demonstrating that the entomopathogenic nematode associated B. cereus and cyclo(4-hydroxy-L-Pro-L-Trp could be used as a biocontrol agents against postharvest fungal disease caused by Aspergillus species.

  7. Trypan Blue Dye Enters Viable Cells Incubated with the Pore-Forming Toxin HlyII of Bacillus cereus

    OpenAIRE

    Tran, Seav-Ly; Puhar, Andrea; Ngo-Camus, Maud; Ramarao, Nalini

    2011-01-01

    Trypan blue is a dye that has been widely used for selective staining of dead tissues or cells. Here, we show that the pore-forming toxin HlyII of Bacillus cereus allows trypan blue staining of macrophage cells, despite the cells remaining viable and metabolically active. These findings suggest that the dye enters viable cells through the pores. To our knowledge, this is the first demonstration that trypan blue may enter viable cells. Consequently, the use of trypan blue staining as a marker ...

  8. Cloning of the beta-amylase gene from Bacillus cereus and characteristics of the primary structure of the enzyme.

    OpenAIRE

    Nanmori, T; M. Nagai; Shimizu, Y.; Shinke, R; Mikami, B

    1993-01-01

    The gene encoding the beta-amylase of Bacillus cereus BQ10-S1 (SpoII) was cloned into Escherichia coli JM 109. A sequenced DNA fragment of 2,001 bp contains the beta-amylase gene. The N-terminal sequences (AVNGKG MNPDYKAYLMAPLKKI), the C-terminal sequences (SHTSSW), and the amino acid sequences of the five regions in the beta-amylase molecules were determined. The mature beta-amylase contains 514 amino acid residues with a molecular mass of 57,885 Da. The amino acid sequence homology with tho...

  9. The effect of nalidixic acid, rifampicin and chloramphenicol on the synthesis of phospholipase C in Bacillus cereus

    International Nuclear Information System (INIS)

    The effect of nalidixic acid, rifampicin and chloramphenicol on the synthesis of phospholipase C (EC 3.1.4.3) has been studied in washed Bacillus cereus cells resuspended in nutrient broth. In the absence of inhibitors, the synthesis showed a biphasic pattern. No synthesis or release of enzyme was found in the presence of chloramphenicol. When rifampicin was added, phospholipase C synthesis for 10-15 min. Nalidixic acid, at concentrations which inhibited DNA synthesis completely, permitted the synthesis of phospholipase C at the same rate and for a similar length of time as rifampicin. (author)

  10. De-hairing protease production by an isolated Bacillus cereus strain AT under solid-state fermentation using cow dung: Biosynthesis and properties

    OpenAIRE

    Vijayaraghavan, Ponnuswamy; Lazarus, Sophia; Vincent, Samuel Gnana Prakash

    2013-01-01

    Agro-industrial residues and cow dung were used as the substrate for the production of alkaline protease by Bacillus cereus strain AT. The bacterial strain Bacillus cereus strain AT produced a high level of protease using cow dung substrate (4813 ± 62 U g−1). Physiological fermentation factors such as the incubation time (72 h), the pH (9), the moisture content (120%), and the inoculum level (6%) played a vital role in the enzyme bioprocess. The enzyme production improved with the supplementa...

  11. Characteristics and phylogeny of Bacillus cereus strains isolated from Maari, a traditional West African food condiment

    DEFF Research Database (Denmark)

    Thorsen, Line; Kando, Christine Kere; Sawadogo, Hagrétou;

    2015-01-01

    cereus occasionally occurs in Maari. This study characterizes succession patterns and pathogenic potential of B. cereus isolated from the raw materials (ash, water from a drilled well (DW) and potash), seed mash throughout fermentation (0-96h), after steam cooking and sun drying (final product) from two......Maari is a spontaneously fermented food condiment made from baobab tree seeds in West African countries. This type of product is considered to be safe, being consumed by millions of people on a daily basis. However, due to the spontaneous nature of the fermentation the human pathogen Bacillus...... production sites of Maari. Aerobic mesophilic bacterial (AMB) counts in raw materials were of 10(5)cfu/ml in DW, and ranged between 6.5×10(3) and 1.2×10(4)cfu/g in potash, 10(9)-10(10)cfu/g in seed mash during fermentation and 10(7) - 10(9) after sun drying. Fifty three out of total 290 AMB isolates were...

  12. Recovery and purification of chitosanase produced by Bacillus cereus using expanded bed adsorption and central composite design.

    Science.gov (United States)

    de Araújo, Nathália Kelly; Pimentel, Vanessa Carvalho; da Silva, Nayane Macedo Portela; de Araújo Padilha, Carlos Eduardo; de Macedo, Gorete Ribeiro; Dos Santos, Everaldo Silvino

    2016-02-01

    This study presents a system for expanded bed adsorption for the purification of chitosanase from broth extract in a single step. A chitosanase-producing strain was isolated and identified as Bacillus cereus C-01 and used to produce chitosanases. The expanded bed adsorption conditions for chitosanase purification were optimized statistically using STREAMLINE(TM) DEAE and a homemade column (2.6 × 30.0 cm). Dependent variables were defined by the quality criteria purification factor (P) and enzyme yield to optimize the chromatographic process. Statistical analyses showed that the optimum conditions for the maximum P were 150 cm/h load flow velocity, 6.0 cm settled bed height, and 7.36 cm distributor height. Distributor height had a strong influence on the process, considerably affecting both the P and enzyme yield. Optimizing the purification variables resulted in an approximately 3.66-fold increase in the P compared with the value under nonoptimized conditions. This system is promising for the recovery of chitosanase from B. cereus C-01 and is economically viable because it promotes the reduction steps. PMID:26638991

  13. Isolation and characterization of glacier VMY22, a novel lytic cold-active bacteriophage of Bacillus cereus

    Institute of Scientific and Technical Information of China (English)

    Xiuling; Ji; Chunjing; Zhang; Yuan; Fang; Qi; Zhang; Lianbing; Lin; Bing; Tang; Yunlin; Wei

    2015-01-01

    As a unique ecological system with low temperature and low nutrient levels, glaciers are considered a "living fossil" for the research of evolution. In this work, a lytic cold-active bacteriophage designated VMY22 against Bacillus cereus MYB41-22 was isolated from Mingyong Glacier in China, and its characteristics were studied. Electron microscopy revealed that VMY22 has an icosahedral head(59.2 nm in length, 31.9 nm in width) and a tail(43.2 nm in length). Bacteriophage VMY22 was classified as a Podoviridae with an approximate genome size of 18 to 20 kb. A one-step growth curve revealed that the latent and the burst periods were 70 and 70 min, respectively, with an average burst size of 78 bacteriophage particles per infected cell. The pH and thermal stability of bacteriophage VMY22 were also investigated. The maximum stability of the bacteriophage was observed to be at pH 8.0 and it was comparatively stable at p H 5.0–9.0. As VMY22 is a cold-active bacteriophage with low production temperature, its characterization and the relationship between MYB41-22 and Bacillus cereus bacteriophage deserve further study.

  14. Emetic Bacillus cereus Are More Volatile Than Thought: Recent Foodborne Outbreaks and Prevalence Studies in Bavaria (2007–2013

    Directory of Open Access Journals (Sweden)

    Ute Messelhäusser

    2014-01-01

    Full Text Available Several Bacillus cereus strains possess the genetic fittings to produce two different types of toxins, the heat-stable cereulide or different heat-labile proteins with enterotoxigenic potential. Unlike the diarrheal toxins, cereulide is (pre-formed in food and can cause foodborne intoxications shortly after ingestion of contaminated food. Based on the widely self-limiting character of cereulide intoxications and rarely performed differential diagnostic in routine laboratories, the real incidence is largely unknown. Therefore, during a 7-year period about 4.300 food samples linked to foodborne illness with a preliminary report of vomiting as well as food analysed in the context of monitoring programs were investigated to determine the prevalence of emetic B. cereus in food environments. In addition, a lux-based real-time monitoring system was employed to assess the significance of the detection of emetic strains in different food matrices and to determine the actual risk of cereulide toxin production in different types of food. This comprehensive study showed that emetic strains are much more volatile than previously thought. Our survey highlights the importance and need of novel strategies to move from the currently taxonomic-driven diagnostic to more risk orientated diagnostics to improve food and consumer safety.

  15. Bacillus cereus Phosphopentomutase Is an Alkaline Phosphatase Family Member That Exhibits an Altered Entry Point into the Catalytic Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Panosian, Timothy D.; Nannemann, David P.; Watkins, Guy R.; Phelan, Vanessa V.; McDonald, W. Hayes; Wadzinski, Brian E.; Bachmann, Brian O.; Iverson, Tina M. (Vanderbilt)

    2011-09-15

    Bacterial phosphopentomutases (PPMs) are alkaline phosphatase superfamily members that interconvert {alpha}-D-ribose 5-phosphate (ribose 5-phosphate) and {alpha}-D-ribose 1-phosphate (ribose 1-phosphate). We investigated the reaction mechanism of Bacillus cereus PPM using a combination of structural and biochemical studies. Four high resolution crystal structures of B. cereus PPM revealed the active site architecture, identified binding sites for the substrate ribose 5-phosphate and the activator {alpha}-D-glucose 1,6-bisphosphate (glucose 1,6-bisphosphate), and demonstrated that glucose 1,6-bisphosphate increased phosphorylation of the active site residue Thr-85. The phosphorylation of Thr-85 was confirmed by Western and mass spectroscopic analyses. Biochemical assays identified Mn{sup 2+}-dependent enzyme turnover and demonstrated that glucose 1,6-bisphosphate treatment increases enzyme activity. These results suggest that protein phosphorylation activates the enzyme, which supports an intermolecular transferase mechanism. We confirmed intermolecular phosphoryl transfer using an isotope relay assay in which PPM reactions containing mixtures of ribose 5-[{sup 18}O{sub 3}]phosphate and [U-{sup 13}C{sub 5}]ribose 5-phosphate were analyzed by mass spectrometry. This intermolecular phosphoryl transfer is seemingly counter to what is anticipated from phosphomutases employing a general alkaline phosphatase reaction mechanism, which are reported to catalyze intramolecular phosphoryl transfer. However, the two mechanisms may be reconciled if substrate encounters the enzyme at a different point in the catalytic cycle.

  16. Effect of iodoacetic acid on 59Fe uptake and aconitase aivity during sporulation of Bacillus cereus T

    International Nuclear Information System (INIS)

    Iodoacetic acid (IAA), a well known inhibitor of glycolysis, inhibited sporulation of B. cereus T when added to the culture just prior to the transition stage at 2-2.5 hr. In the inhibited culture, no considerable aconitase activity and 59Fe uptake were observed. Time studies with IAA in modified G-medium had shown that whenever it was added it prevented further glycolysis of glucose. Addition of IAA at zero hr had no effect on aconitase activity and 59Fe uptake whether glucose was present or absent from the medium. IAA added at rising pH at 3 hr. i.e. after transition period had no effect on the pH characteristics and sporulation of the organism. IAA seems to inhibit the induction of metal transport system. There exists a considerable correlation between aconitase activity and 59Fe uptake during growth and sporulation of B. cereus T in modified G-medium in the presence and absence of glucose. (author)

  17. Structure of the NheA component of the Nhe toxin from Bacillus cereus: implications for function.

    Directory of Open Access Journals (Sweden)

    Magdah Ganash

    Full Text Available The structure of NheA, a component of the Bacillus cereus Nhe tripartite toxin, has been solved at 2.05 Å resolution using selenomethionine multiple-wavelength anomalous dispersion (MAD. The structure shows it to have a fold that is similar to the Bacillus cereus Hbl-B and E. coli ClyA toxins, and it is therefore a member of the ClyA superfamily of α-helical pore forming toxins (α-PFTs, although its head domain is significantly enlarged compared with those of ClyA or Hbl-B. The hydrophobic β-hairpin structure that is a characteristic of these toxins is replaced by an amphipathic β-hairpin connected to the main structure via a β-latch that is reminiscent of a similar structure in the β-PFT Staphylococcus aureus α-hemolysin. Taken together these results suggest that, although it is a member of an archetypal α-PFT family of toxins, NheA may be capable of forming a β rather than an α pore.

  18. ANTIBACTERIAL EFFECT OF GARLIC (ALLIUM SATIVUM AND GINGER (ZINGIBER OFFICINALE AGAINST STAPHYLOCOCCUS AUREUS, SALMONELLA TYPHI, ESCHERICHIA COLI AND BACILLUS CEREUS

    Directory of Open Access Journals (Sweden)

    Bandna Chand

    2013-02-01

    Full Text Available Antibacterial activity of extracts of Allium sativum (garlic and Zingiber officinale (ginger has been evaluated against four different bacteria namely Escherichia coli, Salmonella Typhi, Staphylococcus aureus and Bacillus cereus. Two methods were used to determine the antimicrobial activity of garlic and ginger extracts namely disk diffusion method and agar well diffusion method. Garlic extract exhibited excellent antibacterial activity against all four test organisms while ginger extract showed antibacterial activity against Bacillus cereus and Staphylococcus aureus only. In addition, agar well diffusion method showed higher zone in inhibition when compared with the zone of inhibition produced by the spice of same concentration against the test microorganism by disk diffusion method. Antibiotic sensitivity of the four different bacteria was tested with commercially available antibiotics namely Ciprofloxacin; Oxytetracycline; Vancomycin; Streptomycin; Gentamicin; Tetracycline; Novobiocin; Amikacin and Penicillin G. Penicillin G produced the highest zone of inhibition of 40.00±0.00against Staphylococcus aureus and the lowest zone of inhibition of 0.00±0.00against Escherichia coli.

  19. Literature review on the safety of Toyocerin, a non-toxigenic and non-pathogenic Bacillus cereus var. toyoi preparation.

    Science.gov (United States)

    Williams, Lonnie D; Burdock, George A; Jiménez, Guillermo; Castillo, Marisol

    2009-11-01

    Bacillus cereus var. toyoi is a naturally occurring, non-toxigenic and non-pathogenic strain of B. cereus. Safety studies were conducted on a B. toyoi preparation (Toyocerin, including but not limited to enterotoxicity, eye irritation, genotoxicity, acute, subchronic and chronic toxicity studies and human clinical trials. In rabbits, Toyocerin did not exhibit enterotoxicity and was only slightly irritating to the eyes. It was non-mutagenic in an Ames assay at up to 10,000 microg/plate and did not exhibit clastogenic activity in a chromosomal aberration test at up to 450 mg/ml. It was non-toxic in acute and repeated-dose (30 and 60 days and 1 year) toxicity studies in rats and mice at up to 3 x 10(11)spores/kg bw/day. In an eight-day human clinical trial, Toyocerin did not cause any adverse effects in healthy male and female subjects at 1 x 10(9) and 1 x 10(10)spores/kg bw/day. In feeding trials, Toyocerin not cause any adverse effects in rabbits, pigs, chickens, turkeys and cattle at doses ranging from 8.5 x 10(7) to 4 x 10(9)spores/kg bw/day for durations of 2 weeks to 18 months. Taken together, these studies demonstrate that Toyocerin is safe at the doses tested. PMID:19631708

  20. The Biosynthesis of UDP-D-QuiNAc in Bacillus cereus ATCC 14579.

    Directory of Open Access Journals (Sweden)

    Soyoun Hwang

    Full Text Available N-acetylquinovosamine (2-acetamido-2,6-di-deoxy-D-glucose, QuiNAc is a relatively rare amino sugar residue found in glycans of few pathogenic gram-negative bacteria where it can play a role in infection. However, little is known about QuiNAc-related polysaccharides in gram-positive bacteria. In a routine screen for bacillus glycan grown at defined medium, it was surprising to identify a QuiNAc residue in polysaccharides isolated from this gram-positive bacterium. To gain insight into the biosynthesis of these glycans, we report the identification of an operon in Bacillus cereus ATCC 14579 that contains two genes encoding activities not previously described in gram-positive bacteria. One gene encodes a UDP-N-acetylglucosamine C4,6-dehydratase, (abbreviated Pdeg that converts UDP-GlcNAc to UDP-4-keto-4,6-D-deoxy-GlcNAc (UDP-2-acetamido-2,6-dideoxy-α-D-xylo-4-hexulose; and the second encodes a UDP-4-reductase (abbr. Preq that converts UDP-4-keto-4,6-D-deoxy-GlcNAc to UDP-N-acetyl-quinovosamine in the presence of NADPH. Biochemical studies established that the sequential Pdeg and Preq reaction product is UDP-D-QuiNAc as determined by mass spectrometry and one- and two-dimensional NMR experiments. Also, unambiguous evidence for the conversions of the dehydratase product, UDP-α-D-4-keto-4,6-deoxy-GlcNAc, to UDP-α-D-QuiNAc was obtained using real-time 1H-NMR spectroscopy and mass spectrometry. The two genes overlap by 4 nucleotides and similar operon organization and identical gene sequences were also identified in a few other Bacillus species suggesting they may have similar roles in the lifecycle of this class of bacteria important to human health. Our results provide new information about the ability of Bacilli to form UDP-QuiNAc and will provide insight to evaluate their role in the biology of Bacillus.

  1. Cyclic dipeptides from rhabditid entomopathogenic nematode-associated Bacillus cereus have antimicrobial activities.

    Science.gov (United States)

    Nishanth Kumar, S; Nath, Vishnu Sukumari; Pratap Chandran, R; Nambisan, Bala

    2014-02-01

    The cell free culture filtrate of Bacillus cereus associated with an entomopathogenic nematode, Rhabditis (Oscheius) sp. exhibited strong antimicrobial activity. The ethyl acetate extract of the bacterial culture filtrate was purified by silica gel column chromatography to obtain four bioactive compounds. The structure and absolute stereochemistry of these compounds were determined based on extensive spectroscopic analyses (FABMS, (1)H NMR, (13)C NMR, (1)H-(1)H COSY, (1)H-(13)C HMBC) and Marfey's method. The compounds were identified as cyclic dipeptides (CDPs): cyclo(L-Pro-L-Trp), cyclo(L-Leu-L-Val), cyclo(D-Pro-D-Met), and cyclo(D-Pro-D-Phe), respectively. Compounds recorded significant antibacterial activity against all the test bacteria (Staphylococcus epidermidis, Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa and methicillin-resistant S. aureus) except cyclo(L-Leu-L-Val). Cyclo(L-Leu-L-Val) recorded activity only against Gram positive bacteria. Best antibacterial activity was recorded by cyclo(L-Pro-L-Trp) against S. aureus (4 μg/ml). The four compounds were active against all the five fungi tested (Trichophyton rubrum, Aspergillus flavus, Candida albicans, Candida tropicalis and Cryptococcus neoformans) and the activity was compared with amphotericin B, the standard fungicide. The highest activity of 1 μg/ml by cyclo(L-Pro-L-Trp) was recorded against T. rubrum, a human pathogen responsible for causing athlete's foot, jock itch, and ringworm. The activity of cyclo(L-Pro-L-Trp) against T. rubrum, C. neoformans and C. albicans were better than amphotericin B, the standard antifungal agent. To our knowledge, this is the first report of antifungal activity of CDPs against the human pathogenic fungi T. rubrum and C. neoformans. The four CDPs are nontoxic to healthy human cell line up to 200 μg/ml. We conclude that the bacterium associated with entomopathogenic nematode is promising sources of natural antimicrobial

  2. High-level expression and characterization of two chitinases, ChiCH and ChiCW, of Bacillus cereus 28-9 in Escherichia coli

    International Nuclear Information System (INIS)

    Many chitinase genes have been cloned and sequenced from prokaryotes and eukaryotes but overexpression of chitinases in Escherichia coli cells was less reported. ChiCH and ChiCW of Bacillus cereus 28-9 belong to two distinct groups based on their amino acid sequences of catalytic domains, and in addition, domain structures of two enzymes are different. In this study, we established an ideal method for high-level expression of chitinases in E. coli as glutathione-S-transferase fusion proteins using pGEX-6P-1 vector. Both ChiCH and ChiCW were successfully highly expressed in E. coli cells as soluble GST-chitinase fusion proteins, and recombinant native ChiCH and ChiCW could be purified after cleavage with PreScission protease to remove GST tag. Purified chitinases were used for biochemical characterization of kinetics, hydrolysis products, and binding activities. The results indicate that ChiCW is an endo-chitinase and effectively hydrolyzes chitin and chito-multimers to chito-oligomers and the end product chitobiose, and ChiCH is an exo-chitinase and degrades chito-oligomers to produce chitobiose. Furthermore, due to higher affinity of ChiCW toward colloidal chitin than Avicel, C-terminal domain of ChiCW should be classified as a chitin-binding domain not a cellulose-binding domain although that was revealed as a cellulose-binding domain by conserved domain analysis. Therefore, the method of high-level expression of chitinases is helpful to studies and applications of chitinases

  3. Incestuous rape, abjection, and the colonization of psychic space in Toni Morrison’s The Bluest Eye and Shani Mootoo’s Cereus Blooms at Night

    NARCIS (Netherlands)

    E.M. Koopman (Emy)

    2012-01-01

    textabstractToni Morrison’s The Bluest Eye (1970) and Shani Mootoo’s Cereus Blooms at Night (1996) both apply a strategy of connecting rape to other forms of oppression, suggesting that incest is at least partly the result of the dynamics of being colonized and “othered”. This article brings out the

  4. Germination of Bacillus cereus spores is induced by germinants from differentiated caco-2 cells, a human cell line mimicking the epithelial cells of the small intestine

    OpenAIRE

    Wijnands, L. M.; Dufrenne, J. B.; Leusden, van, F.M.; Abee, T.

    2007-01-01

    Spores of 11 enterotoxigenic strains of Bacillus cereus isolated from foods and humans adhered with similar efficiencies to Caco-2 cells, whereas subsequent germination triggering was observed with only 8 of these strains. Notably, Hep-2 cells did not trigger germination, while spores of all strains displayed similar germination efficiencies in brain heart infusion broth.

  5. De-mercurization of wastewater by Bacillus cereus (JUBT1): Growth kinetics, biofilm reactor study and field emission scanning electron microscopic analysis

    International Nuclear Information System (INIS)

    Graphical abstract: The assembly of biofilm reactor, based on attached growth of Bacillus cereus (JUBT1) on rice husk packing, and an activated carbon filter has been able to ensure the removal of mercury up to near-zero level. Highlights: → A new mercury resistant bacterial strain, Bacillus cereus (JUBT1), has been isolated. → Growth kinetics has been determined. → Biofilm reactor using attached growth of bacteria ensures near-zero level of mercury. → Confinement of mercury is confirmed through energy dispersive spectrometric analysis. - Abstract: Removal of mercuric ions by a mercury resistant bacteria, called Bacillus cereus (JUBT1), isolated from the sludge of a local chlor-alkali industry, has been investigated. Growth kinetics of the bacteria have been determined. A multiplicative, non-competitive relationship between sucrose and mercury ions has been observed with respect to bacterial growth. A combination of biofilm reactor, using attached growth of Bacillus cereus (JUBT1) on rice husk packing, and an activated carbon filter has been able to ensure the removal of mercury up to near-zero level. Energy dispersive spectrometry analysis of biofilm and the activated carbon has proved the transformation of Hg2+ to Hg0 and its confinement in the system.

  6. 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.

    Science.gov (United States)

    Forghani, Fereidoun; Wei, Shuai; Oh, Deog-Hwan

    2016-05-01

    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 . PMID:27296430

  7. De-mercurization of wastewater by Bacillus cereus (JUBT1): Growth kinetics, biofilm reactor study and field emission scanning electron microscopic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ghoshal, Sanjukta; Bhattacharya, Pinaki [Chemical Engineering Department, Jadavpur University Kolkata 700 032, West Bengal (India); Chowdhury, Ranjana, E-mail: ranjana.juchem@gmail.com [Chemical Engineering Department, Jadavpur University Kolkata 700 032, West Bengal (India)

    2011-10-30

    Graphical abstract: The assembly of biofilm reactor, based on attached growth of Bacillus cereus (JUBT1) on rice husk packing, and an activated carbon filter has been able to ensure the removal of mercury up to near-zero level. Highlights: {yields} A new mercury resistant bacterial strain, Bacillus cereus (JUBT1), has been isolated. {yields} Growth kinetics has been determined. {yields} Biofilm reactor using attached growth of bacteria ensures near-zero level of mercury. {yields} Confinement of mercury is confirmed through energy dispersive spectrometric analysis. - Abstract: Removal of mercuric ions by a mercury resistant bacteria, called Bacillus cereus (JUBT1), isolated from the sludge of a local chlor-alkali industry, has been investigated. Growth kinetics of the bacteria have been determined. A multiplicative, non-competitive relationship between sucrose and mercury ions has been observed with respect to bacterial growth. A combination of biofilm reactor, using attached growth of Bacillus cereus (JUBT1) on rice husk packing, and an activated carbon filter has been able to ensure the removal of mercury up to near-zero level. Energy dispersive spectrometry analysis of biofilm and the activated carbon has proved the transformation of Hg{sup 2+} to Hg{sup 0} and its confinement in the system.

  8. Inactivation of Bacillus cereus and Salmonella enterica serovar Typhimurium by aqueous ozone (O3): Modeling and Uv-Vis spectroscopic analysis

    Science.gov (United States)

    Ozone (O3) is a natural antimicrobial agent with potential applications in food industry. In this study, inactivation of Bacillus cereus and Salmonella enterica Typhimurium by aqueous ozone was evaluated. Ozone gas was generated using a domestic ozone generator with an output of 200 mg/hr (approx. 0...

  9. Representative Ensembles in Statistical Mechanics

    OpenAIRE

    V. I. YUKALOV

    2007-01-01

    The notion of representative statistical ensembles, correctly representing statistical systems, is strictly formulated. This notion allows for a proper description of statistical systems, avoiding inconsistencies in theory. As an illustration, a Bose-condensed system is considered. It is shown that a self-consistent treatment of the latter, using a representative ensemble, always yields a conserving and gapless theory.

  10. Presensitization of microorganisms by essential oils treatments to low dose gamma irradiation with special reference to Bacillus cereus ATCC 7004

    International Nuclear Information System (INIS)

    The radiosensitization of B.cereus ATCC 7004 spores was evaluated in the presence of thymol, thyme, D-L menthol, trans-cinnamaldehyde and eugenol in ground beef. Cattle minced meat (5% fat) was inoculated with spores of B.cereus (10 5 - 10 6 CFU/g), and each compound was added separately at various concentrations. The antimicrobial potential was evaluated in unirradiated meat by determining the MIC in percentage (wt/wt) after 24 h of storage at 4 ± 1 C. Results showed that the best antimicrobial compound was the trans-cinnamaldehyde with MIC of 1.47%, wt/wt. In presence of cinnamaldehyde, the addition of sodium pyrophosphate decahydrate (0.1% wt/wt) increased significantly (P < 0.05) the relative sensitivity of B.cereus spores 2 times. However, the presence of ascorbic acid in the media reduced significantly (p<0.05) the radiosensitivity of bacteria. The combined effect of gamma irradiation in presence of cinnamaldehyde, added with ascorbic acid or sodium pyrophosphate decahydrate, on the microbiological and physicochemical characteristic of meat samples was evaluated at 2kGy under air. The use of the active compounds with the irradiation reduced significantly (p<0.05) the count of total bacteria with a concomitant effect in the extension periods of shelf life. The addition of the cinnamaldehyde induced a significant reduction (p<0.05) in TVN and free amino acids of irradiated samples. In presence of ascorbic acid the thiobarbituric acid-reactive amino acids of irradiated samples. In presence of ascorbic acid the thiobarbiturate acid-reactive substances (TBARS) concentration was significantly reduced (p<0.05). A significant reduction (p<0.05) of a* and c* of color values and a significant increase (p<0.05) of b* value were obtained for the samples treated by the cinnamaldehyde. The application of bioactive films for the immobilization of the essential oils is a good alternate to check their stability during storage time

  11. A strain-variable bacteriocin in Bacillus anthracis and Bacillus cereus with repeated Cys-Xaa-Xaa motifs

    Directory of Open Access Journals (Sweden)

    Haft Daniel H

    2009-04-01

    Full Text Available Abstract Bacteriocins are peptide antibiotics from ribosomally translated precursors, produced by bacteria often through extensive post-translational modification. Minimal sequence conservation, short gene lengths, and low complexity sequence can hinder bacteriocin identification, even during gene calling, so they are often discovered by proximity to accessory genes encoding maturation, immunity, and export functions. This work reports a new subfamily of putative thiazole-containing heterocyclic bacteriocins. It appears universal in all strains of Bacillus anthracis and B. cereus, but has gone unrecognized because it is always encoded far from its maturation protein operon. Patterns of insertions and deletions among twenty-four variants suggest a repeating functional unit of Cys-Xaa-Xaa. Reviewers This article was reviewed by Andrei Osterman and Lakshminarayan Iyer.

  12. Properties of ATP dependent deoxyribonuclease and its possible role in deoxyribonucleic acid degradation of bacillus cereus irradiated by ultraviolet light

    International Nuclear Information System (INIS)

    DNA degradation and an increased level of DNAses in the crude extract of irradiated B. cereus culture has been observed. As a result of a more detailed study of ATP dependent DNAse, the optimum pH and ATP dependency, furthermore optimum ATP concentration were established. The enzyme degrades the native DNA at a rate about 4-5 times higher than the thermally denaturated DNA. Samples of the DNA irradiated by increasing doses of U.V.-light were hydrolysed at decreasing rates. The native and U.V. irradiated DNA were degraded at nearly equal rates, on this basis it is supposed that the enzyme preferentially forms a complex with the native rather than with the irradiated DNA

  13. Changes in ultraviolet resistance and photoproduct formation as early events in spore germination of Bacillus cereus T

    International Nuclear Information System (INIS)

    In order to determine the timing of the change in the state of DNA in bacterial spores during the course of germination, L-alanine-induced germination of Bacillus cereus spores was interrupted by 0.3M CaCl2 as an inhibitor, and the resulting semi-refractive spores (spores at the end of the first phase of germination) were examined for UV-resistance and photoproduct formation. Upon UV-irradiation, these spores, still having a semi-refractile core as observed under a phase-contrast microscope, gave rise to mainly the cyclobutane-type thymine dimer. It was concluded that change in the stats of the spore DNA occurs early in the process of germination, i.e. before the refractility of the core is lost. It was also found that CaCl2 markedly prolonged the duration of the transient UV-resistant stage. (author)

  14. Bacillus Cereus GD 55 Strain Improvement by Physical and Chemical Mutagenesis for Enhanced Production of Fibrinolytic Protease

    Directory of Open Access Journals (Sweden)

    E. VENKATA NAGA RAJU

    2013-05-01

    Full Text Available This work has been undertaken to enhance the production of industrially important fibrinolytic protease by subjecting indigenous fibrinolytic protease producing Bacillus cereus to strain improvement by random mutagenesis using ultra-violet (UV irradiation, ethyl methane sulfonate (EMS and ethidium bromide treatment. Mutants were screened on the basis of enzyme assay by spectrophotometer using folin’s phenol reagent. Ethyl methane sulfonate (EMS and ethidium bromide treated Bacillus cereus GD 55 was proved to be the best for optimum production of fibrinolytic protease. The effect of different production parameters such as carbon source, inoculum sizes, pH, temperature, nitrogen source (inorganic and organic and incubation time on fibrinolytic protease production by the mutated bacterial strain was studied. The enzyme production was assayed in submerged fermentation (SmF condition. The maximum fibrinolytic protease production was observed with fructose 1% (18.60 ± 0.62 U/ml, inoculum size level 2% (22.10 ± 0.80 U/ml, pH 8.0 (28.65 ± 0.41 U/ml, temperature 35°C (28.68 ± 0.19 U/ml, NH4NO3 1% (34.24 ± 0.12 U/ml, peptone 1% (35.68 ± 0.27 U/ml and incubation time 48 hours (38.92 ± 0.56 U/ml in the production medium. EMS&EB-15 mutant strains were found to produce 2-4 fold more enzyme. Thus these findings have more impact on enzyme economy for biotechnological applications of microbial fibrinolytic proteases.

  15. Recovery of Heat Treated Bacillus cereus Spores Is Affected by Matrix Composition and Factors with Putative Functions in Damage Repair.

    Science.gov (United States)

    Warda, Alicja K; Tempelaars, Marcel H; Abee, Tjakko; Nierop Groot, Masja N

    2016-01-01

    The ability of spores to recover and grow out after food processing is affected by cellular factors and by the outgrowth conditions. In the current communication we studied the recovery and outgrowth of individually sorted spores in BHI and rice broth media and on agar plates using flow cytometry. We show that recovery of wet heat treated Bacillus cereus ATCC 14579 spores is affected by matrix composition with highest recovery in BHI broth or on rice agar plates, compared to BHI agar plates and rice broth. Data show that not only media composition but also its liquid or solid state affect the recovery of heat treated spores. To determine the impact of factors with putative roles in recovery of heat treated spores, specific genes previously shown to be highly expressed in outgrowing heat-treated spores were selected for mutant construction. Spores of nine B. cereus ATCC 14579 deletion mutants were obtained and their recovery from wet heat treatment was evaluated using BHI and rice broth and agar plates. Deletion mutant spores showed different capacity to recover from heat treatment compared to wild type with the most pronounced effect for a mutant lacking BC5242, a gene encoding a membrane protein with C2C2 zinc finger which resulted in over 95% reduction in recovery compared to the wild type in BHI broth. Notably, similar relative performance of wild type and mutants was observed using the other recovery conditions. We obtained insights on the impact of matrix composition and state on recovery of individually sorted heat treated spores and identified cellular factors with putative roles in this process. These results may provide leads for future developments in design of more efficient combined preservation treatments. PMID:27486443

  16. The Mutation Glu151Asp in the B-Component of the Bacillus cereus Non-Hemolytic Enterotoxin (Nhe) Leads to a Diverging Reactivity in Antibody-Based Detection Systems

    OpenAIRE

    Andrea Didier; Nadja Jeßberger; Victoria Krey; Richard Dietrich; Siegfried Scherer; Erwin Märtlbauer

    2015-01-01

    The ability of Bacillus cereus to cause foodborne toxicoinfections leads to increasing concerns regarding consumer protection. For the diarrhea-associated enterotoxins, the assessment of the non-hemolytic enterotoxin B (NheB) titer determined by a sandwich enzyme immunoassay (EIA) correlates best with in vitro cytotoxicity. In general, the regulation of enterotoxin expression of B. cereus is a coordinately-regulated process influenced by environmental, and probably also by host factors. As lo...

  17. Robust Group Linkage

    OpenAIRE

    Li, Pei; Dong, Xin Luna; Guo, Songtao; Maurino, Andrea; Srivastava, Divesh

    2015-01-01

    We study the problem of group linkage: linking records that refer to entities in the same group. Applications for group linkage include finding businesses in the same chain, finding conference attendees from the same affiliation, finding players from the same team, etc. Group linkage faces challenges not present for traditional record linkage. First, although different members in the same group can share some similar global values of an attribute, they represent different entities so can also...

  18. Representing Learning With Graphical Models

    Science.gov (United States)

    Buntine, Wray L.; Lum, Henry, Jr. (Technical Monitor)

    1994-01-01

    Probabilistic graphical models are being used widely in artificial intelligence, for instance, in diagnosis and expert systems, as a unified qualitative and quantitative framework for representing and reasoning with probabilities and independencies. Their development and use spans several fields including artificial intelligence, decision theory and statistics, and provides an important bridge between these communities. This paper shows by way of example that these models can be extended to machine learning, neural networks and knowledge discovery by representing the notion of a sample on the graphical model. Not only does this allow a flexible variety of learning problems to be represented, it also provides the means for representing the goal of learning and opens the way for the automatic development of learning algorithms from specifications.

  19. Burnout in Customer Service Representatives

    OpenAIRE

    Tariq Jalees; Javed Zeeshan

    2008-01-01

    The purpose and aim of this research was to (1) identify the factors that contributes towards job burnout in sales service representative (2) What are the relationships of these factors (3) To empirically test the relationships of the determinants relating to burnout in customer service representatives. Based on literature survey six different variables related to burnout were identified. The variables were (1) Emotional exhaustion.(2) Reduced personal accomplishment.(3) Job induced tension.(...

  20. Groups as Graphs

    CERN Document Server

    Kandasamy, W B Vasantha

    2009-01-01

    For the first time we represent every finite group in the form of a graph in this book. The authors choose to call these graphs as identity graph, since the main role in obtaining the graph is played by the identity element of the group. This study is innovative because through this description one can immediately look at the graph and say the number of elements in the group G which are self-inversed. Also study of different properties, like the subgroups of a group, normal subgroups of a group, p-sylow subgroups of a group and conjugate elements of a group are carried out using the identity graph of the group in this book. This book has four chapters. The first chapter is introductory. The second chapter represents groups as graphs. In the third chapter, we have defined similar types of graphs for algebraic structures like commutative semigroups, loops, commutative groupoids and commutative rings. The final chapter poses 52 problems.

  1. Bioaccumulation of copper, zinc, cadmium and lead by Bacillus sp., Bacillus cereus, Bacillus sphaericus and Bacillus subtilis Bioacumulação de cobre, zinco, cádmio e chumbo por Bacillus sp., Bacillus cereus, Bacillus sphaericus e Bacillus subtilis

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Augusto da Costa

    2001-03-01

    Full Text Available This work presents some results on the use of microbes from the genus Bacillus for uptake of cadmium, zinc, copper and lead ions. Maximum copper bioaccumulations were 5.6 mol/g biomass for B. sphaericus, 5.9 mol/g biomass for B. cereus and B. subtilis, and 6.4 mol/g biomass for Bacillus sp. Maximum zinc bioaccumulations were 4.3 mol/g biomass for B. sphaericus, 4.6 mol/g biomass for B. cereus, 4.8 mol/g biomass for Bacillus sp. and 5.0 mol/g biomass for B. subtilis. Maximum cadmium bioaccumulations were 8.0 mol/g biomass for B. cereus, 9.5 mol/g biomass for B. subtilis, 10.8 mol/g biomass for Bacillus sp. and 11.8 mol/g biomass for B. sphaericus. Maximum lead biomaccumulations were 0.7 mol/g biomass for B. sphaericus, 1.1 mol/g biomass for B. cereus, 1.4 mol/g biomass for Bacillus sp. and 1.8 mol/g biomass for B. subtilis. The different Bacillus strains tested presented distinct uptake capacities, and the best results were obtained for B. subtilis and B. cereus.Este trabalho apresenta resultados de acumulação dos íons metálicos cádmio, zinco, cobre e chumbo por bactérias do gênero Bacillus. A bioacumulação máxima de cobre foi 5,6 mol/g biomassa para B. sphaericus, 5,9 mol/g biomassa para B. cereus e B. subtilis, e 6,4 mol/g biomassa para Bacillus sp.. A bioacumulação máxima de zinco foi 4,3 mol/g biomassa para B. sphaericus, 4,6 mol/g biomassa para B. cereus, 4,8 mol/g biomassa para Bacillus sp. e 5,0 mol/g biomassa para B. subtilis. A bioacumulação máxima de cádmio foi 8,0 mol/g biomassa para B. cereus, 9,5 mol/g biomassa para B. subtilis, 10,8 mol/g biomassa para Bacillus sp. e 11,8 mol/g biomassa para B. sphaericus. A bioacumulação máxima de chumbo foi 0,7 mol/g biomassa para B. sphaericus, 1,1 mol/g biomassa para B. cereus, 1,4 mol/g biomassa para Bacillus sp. e 1,8 mol/g biomassa para B. subtilis. As distintas linhagens de Bacillus testadas apresentaram variáveis capacidades de carregamento de íons metálicos, sendo os

  2. Inhibitory and Lethal Effects of Aqueous and Ethanolic Extracts of Kelussia odoratissima on Bacillus cereus , Listeria innocua and Escherichia coli "in vitro"

    Directory of Open Access Journals (Sweden)

    Maryam Heidari Sureshjani

    2014-01-01

    Full Text Available Abstract Background and objectives: Karafs Koohi with the scientific name of Kelussia odoratissima and the local name of Keloss belongs to the Apiaceace family, and is a biannual or perennial plant. The present study aims at investigating the antimicrobial effects of the ethanolic and aqueous extracts of Kelussia odoratissima on Bacillus cereus , Listeria innocua and Escherichia coli Materials and methods: In this study, different concentration levels (20, 40, 60, 80 mg/ml of ethanolic and aqueous extracts of Kelussia odoratissima leaves were prepared. The antibacterial effect of extracts were investigated using spreading of the extract on medium surface (pour plate and disk agar diffusion test. Minimum Inhibitory Concentration (MIC( and Minimum Bactericidal Concentration (MBC were also studied using the dilution method .Statistical analysis was carried out by analysis of variance (ANOVA. Results: In disk agar diffusion Method all concentrations of ethanolic extract have inhibitory effect against Bacillus cereus and Listeria innocua. Minimum Inhibitory Concentration (MIC( of Kelussia odoratissima leaves of aqueous and ethanolic extracts for Bacillus cereus and Listeria innocua was 16 and 8 mg/ml and for Escherichia coli was 32and 16 mg/ml, respectively . Minimum Bactericidal Concentration (MBC of Kelussia odoratissima leaves of aqueous and ethanolic extracts for Bacillus cereus and Listeria innocua was 32 and 16 mg/ml and for Escherichia coli was 64 and 32mg/ml, respectively. Escherichia coli exhibited the most resistance against aqueous and ethanol extracts of Kelussia odoratissima leaves. Conclusions: The results showed that the ethanolic extract of Kelussia odoratissima leaves had greater inhibitory effects on the strains studied compared to aqueous extracts in vitro.

  3. NIH 3T3 cells stably transfected with the gene encoding phosphatidylcholine-hydrolyzing phospholipase C from Bacillus cereus acquire a transformed phenotype.

    OpenAIRE

    Johansen, T.; Bjørkøy, G; Overvatn, A; Diaz-Meco, M T; Traavik, T; Moscat, J

    1994-01-01

    In order to determine whether chronic elevation of intracellular diacylglycerol levels generated by hydrolysis of phosphatidylcholine (PC) by PC-hydrolyzing phospholipase C (PC-PLC) is oncogenic, we generated stable transfectants of NIH 3T3 cells expressing the gene encoding PC-PLC from Bacillus cereus. We found that constitutive expression of this gene (plc) led to transformation of NIH 3T3 cells as evidenced by anchorage-independent growth in soft agar, formation of transformed foci in tiss...

  4. Spores from mesophilic Bacillus cereus strains germinate better and grow faster in simulated gastro-intestinal conditions than spores from psychrotrophic strains.

    OpenAIRE

    Wijnands, L. M.; Dufrenne, J. B.; Zwietering, M.H.; van Leusden, F. M.

    2006-01-01

    The species Bacillus cereus, known for its ability to cause food borne disease, consists of a large variety of strains. An important property for discrimination of strains is their growth temperature range. Psychrotrophic strains can grow well at refrigerator temperatures but grow at 37 degrees C with difficulty. Mesophilic strains on the other hand are unable to grow below 10 degrees C, but grow well at 37 degrees C. Spores of six psychrotrophic and six mesophilic strains were investigated f...

  5. Interactive and Single Effects of Ectomycorrhiza Formation and Bacillus cereus on Metallothionein MT1 Expression and Phytoextraction of Cd and Zn by Willows

    OpenAIRE

    Hrynkiewicz, Katarzyna; Dabrowska, Grazyna; Baum, Christel; Niedojadlo, Katarzyna; Leinweber, Peter

    2011-01-01

    Single and joint ectomycorrhizal (+ Hebeloma mesophaeum) and bacterial (+ Bacillus cereus) inoculations of willows (Salix viminalis) were investigated for their potential and mode of action in the promotion of cadmium (Cd) and zinc (Zn) phytoextraction. Dual fungal and bacterial inoculations promoted the biomass production of willows in contaminated soil. Single inoculations either had no effect on the plant growth or inhibited it. All inoculated willows showed increased concentrations of nut...

  6. Stem Bark Extract and Fraction of Persea americana (Mill.) Exhibits Bactericidal Activities against Strains of Bacillus cereus Associated with Food Poisoning

    OpenAIRE

    Akinpelu, David A.; Aiyegoro, Olayinka A.; Akinpelu, Oluseun F.; Okoh, Anthony I.

    2014-01-01

    The study investigates the in vitro antibacterial potentials of stem bark extracts of Persea americana on strains of Bacillus cereus implicated in food poisoning. The crude stem bark extracts and butanolic fraction at a concentration of 25 mg/mL and 10 mg/mL, respectively, exhibited antibacterial activities against test isolates. The zones of inhibition exhibited by the crude extract and the fraction ranged between 10 mm and 26 mm, while the minimum inhibitory concentration values ranged betw...

  7. Modelling the influence of palmitic, palmitoleic, stearic and oleic acids on apparent heat resistance of spores of Bacillus cereus NTCC 11145 and Clostridium sporogenes Pasteur 79.3

    OpenAIRE

    Mvou Lekogo, Brice; Coroller, Louis; Mathot, Anne Gabrielle; Mafart, Pierre; Leguérinel, Ivan

    2010-01-01

    Heat resistance of spores is affected by many factors such as temperature, pH, water activity (aw) and others. Previous studies have reported that free fatty acids can affect the germination and growth of bacterial spores. In this study, we investigated the influence of free fatty acids in heating medium or in recovery medium on the heat resistance of spores of Bacillus cereus NTCC 11145 and Clostridium sporogenes Pasteur 79.3. Four free fatty acids were studied: palmitic, palmitoleic, steari...

  8. Secreted Compounds of the Probiotic Bacillus clausii Strain O/C Inhibit the Cytotoxic Effects Induced by Clostridium difficile and Bacillus cereus Toxins.

    Science.gov (United States)

    Ripert, Gabrielle; Racedo, Silvia M; Elie, Anne-Marie; Jacquot, Claudine; Bressollier, Philippe; Urdaci, Maria C

    2016-06-01

    Although the use of probiotics based on Bacillus strains to fight off intestinal pathogens and antibiotic-associated diarrhea is widespread, the mechanisms involved in producing their beneficial effects remain unclear. Here, we studied the ability of compounds secreted by the probiotic Bacillus clausii strain O/C to counteract the cytotoxic effects induced by toxins of two pathogens, Clostridium difficile and Bacillus cereus, by evaluating eukaryotic cell viability and expression of selected genes. Coincubation of C. difficile and B. cereus toxic culture supernatants with the B. clausii supernatant completely prevented the damage induced by toxins in Vero and Caco-2 cells. The hemolytic effect of B. cereus was also avoided by the probiotic supernatant. Moreover, in these cells, the expression of rhoB, encoding a Rho GTPase target for C. difficile toxins, was normalized when C. difficile supernatant was pretreated using the B. clausii supernatant. All of the beneficial effects observed with the probiotic were abolished by the serine protease inhibitor phenylmethylsulfonyl fluoride (PMSF). Suspecting the involvement of a secreted protease in this protective effect, a protease was purified from the B. clausii supernatant and identified as a serine protease (M-protease; GenBank accession number Q99405). Experiments on Vero cells demonstrated the antitoxic activity of the purified protease against pathogen supernatants. This is the first report showing the capacity of a protease secreted by probiotic bacteria to inhibit the cytotoxic effects of toxinogenic C. difficile and B. cereus strains. This extracellular compound could be responsible, at least in part, for the protective effects observed for this human probiotic in antibiotic-associated diarrhea. PMID:27001810

  9. Cultural skepticism and 'group representation'

    OpenAIRE

    Phillips, Anne

    2011-01-01

    Arguments for group representation have commonly faced three objections: (1) that representing people via their membership of a group promotes sectionalism, parochialism, and the pursuit of vested interests; (2) that it raises impossible questions about which groups qualify for group representation; (3) that it falsely presumes the existence of a group with sufficiently shared interests, perspectives, values, or concerns for some of those group members fairly to represent the others. I have s...

  10. Expression of the genes encoding the CasK/R two-component system and the DesA desaturase during Bacillus cereus cold adaptation.

    Science.gov (United States)

    Diomandé, Sara Esther; Doublet, Bénédicte; Vasaï, Florian; Guinebretière, Marie-Hélène; Broussolle, Véronique; Brillard, Julien

    2016-08-01

    Two-component systems (TCS) allow a cell to elaborate a variety of adaptive responses to environment changes. The recently discovered CasK/R TCS plays a role in the optimal unsaturation of fatty acids necessary for cold adaptation of the foodborne-pathogen Bacillus cereus Here, we showed that the promoter activity of the operon encoding this TCS was repressed during growth at low temperature in the stationary phase in the parental strain when compared to the casK/R mutant, suggesting that CasR negatively regulates the activity of its own promoter in these conditions. The promoter activity of the desA gene encoding the Δ5 fatty acid desaturase, providing unsaturated fatty acids (UFAs) required for low temperature adaptation, was repressed in the casK/R mutant grown at 12°C versus 37°C. This result suggests that CasK/R activates desA expression during B. cereus growth at low temperature, allowing an optimal unsaturation of the fatty acids. In contrast, desA expression was repressed during the lag phase at low temperature in presence of UFAs, in a CasK/R-independent manner. Our findings confirm that the involvement of this major TCS in B. cereus cold adaptation is linked to the upregulation of a fatty acid desaturase. PMID:27435329

  11. Interactive and Single Effects of Ectomycorrhiza Formation and Bacillus cereus on Metallothionein MT1 Expression and Phytoextraction of Cd and Zn by Willows.

    Science.gov (United States)

    Hrynkiewicz, Katarzyna; Dabrowska, Grazyna; Baum, Christel; Niedojadlo, Katarzyna; Leinweber, Peter

    2012-03-01

    Single and joint ectomycorrhizal (+ Hebeloma mesophaeum) and bacterial (+ Bacillus cereus) inoculations of willows (Salix viminalis) were investigated for their potential and mode of action in the promotion of cadmium (Cd) and zinc (Zn) phytoextraction. Dual fungal and bacterial inoculations promoted the biomass production of willows in contaminated soil. Single inoculations either had no effect on the plant growth or inhibited it. All inoculated willows showed increased concentrations of nutritional elements (N, P, K and Zn) and decreased concentrations of Cd in the shoots. The lowest biomass production and concentration of Cd in the willows (+ B. cereus) were combined with the strongest expression of metallothioneins. It seems that biotic stress from bacterial invasion increased the synthesis of these stress proteins, which responded in decreased Cd concentrations. Contents of Cd and Zn in the stems of willows were combination-specific, but were always increased in dual inoculated plants. In conclusion, single inoculations with former mycorrhiza-associated B. cereus strains decreased the phytoextraction efficiency of willows by causing biotic stress. However, their joint inoculation with an ectomycorrhizal fungus is a very promising method for promoting the phytoextraction of Cd and Zn through combined physiological effects on the plant. PMID:22389535

  12. Purification and partial characterization of a novel calcium-binding protein from Bacillus cereus T spores and inhibition of germination by calmodulin antagonists

    International Nuclear Information System (INIS)

    A novel calcium-binding protein has been purified from the dormant spores of Bacillus cereus T. B. cereus T spores were extensively washed, broken, and heated at 90 degree C for 2 min. Using calcium-dependent hydrophobic interaction chromatography plus DEAE-cellulose and hydroxylapatite columns, a single protein was obtained which possessed calcium-binding capacity and some characteristics of calmodulin. This heat-stable protein was retained by hydrophobic matrices or a calmodulin antagonist in a calcium-dependent manner. The crude spore extract displaced bovine brain calmodulin from its antibody in a radioimmunoassay and the immunoreactive specific activity of the partially purified fraction which eluted from phenyl-Sepharose was ca. 200-fold greater than the crude spore extract. Purity of this protein was verified by sodium dodecyl sulfate-polyarcylamide gel electrophoresis and reversed-phase HPLC. Calcium-binding ability was verified with a competitive calcium binding assay using Chelex-100 resin and 45Ca autoradiography. SDS-PAGE and amino acid composition indicated the molecular weight of the protein was 24-kDa. The effects of two calmodulin antagonists, trifluoperazine (TFP) and N-(6-aminohexyl)-5-chloro-1-naphthalene sulfonamide (W-7) on L-alanine-induced germination of Bacillus cereus T spores were examined by measuring commitment to germination, loss of heat resistance, release of calcium, decrease in optical density at 660 nm and phase-contrast microscopy

  13. Marc Treib: Representing Landscape Architecture

    DEFF Research Database (Denmark)

    Braae, Ellen Marie

    The editor of Representing Landscape Architecture, Marc Treib, argues that there is good reason to evaluate the standard practices of representation that landscape architects have been using for so long. In the rush to the promised land of computer design these practices are now in danger of being...... left by the wayside. The 14 often both fitting and well crafted contributions of this publication offer an approach to how landscape architecture has been and is currently represented; in the design study, in presentation, in criticism, and in the creation of landscape architecture....

  14. Blooming rhythms of cactus Cereus peruvianus with nocturnal peak at full moon during seasons of prolonged daytime photoperiod.

    Science.gov (United States)

    Ben-Attia, Mossadok; Reinberg, Alain; Smolensky, Michael H; Gadacha, Wafa; Khedaier, Achraf; Sani, Mamane; Touitou, Yvan; Boughamni, Néziha Ghanem

    2016-01-01

    Cereus peruvianus (Peruvian apple cactus) is a large erect and thorny succulent cactus characterized by column-like (cereus [L]: column), that is, candle-shaped, appendages. For three successive years (1100 days), between early April and late November, we studied the flowering patterns of eight cacti growing in public gardens and rural areas of north and central Tunisia, far from nighttime artificial illumination, in relation to natural environmental light, temperature, relative humidity and precipitation parameters. Flower blooming was assessed nightly between 23:00 h and until at least 02:00 h, and additionally around-the-clock at ~1 h intervals for 30 consecutive days during the late summer of each year of study to quantify both nyctohemeral (day-night) and lunar patterns. During the summer months of prolonged daytime photoperiod, flower blooming of C. peruvianus exhibited predictable-in-time variation as "waves" with average period of 29.5 days synchronized by the light of the full moon. The large-sized flower (~16 cm diameter) opens almost exclusively at night, between sunset and sunrise, as a 24 h rhythm during a specific 3-4-day span of the lunar cycle (full moon), with a strong correlation between moon phase and number and proportion of flowers in bloom (ranging from r = +0.59 to +0.91). Black, blue and red cotton sheets were used to filter specific spectral bands of nighttime moonlight from illuminating randomly selected plant appendages as a means to test the hypothesis of a "gating" 24 h rhythm phenomenon of photoreceptors at the bud level. Relative to control conditions (no light filtering), black sheet covering inhibited flower bud induction by 87.5%, red sheet covering by 46.6% and blue sheet covering by 34%, and the respective inhibiting effects on number of flowers in bloom were essentially 100%, ~81% and ~44%. C. peruvianus is a unique example of a terrestrial plant that exhibits a circadian flowering rhythm (peak ~00:00 h) "gated" by 24 h, lunar

  15. Bacillus cereus AR156 Extracellular Polysaccharides Served as a Novel Micro-associated Molecular Pattern to Induced Systemic Immunity to Pst DC3000 in Arabidopsis.

    Science.gov (United States)

    Jiang, Chun-Hao; Fan, Zhi-Hang; Xie, Ping; Guo, Jian-Hua

    2016-01-01

    Non-host resistance (NHR) is a broad-spectrum plant defense. Upon colonizing on the surface on the root or leaves of non-host species, pathogens initial encounter preform and induce defense response in plant, such as induced hypersensitive response, PAMPs triggered immunity (PTI), and effector triggered immunity (ETI). The ability of plants to develop an induced systemic response (ISR) in reaction to the colonization by non-pathogenic rhizobacterium depends on interactions between host plants and the colonizing rhizobacterium, and the ISR also can be defined as a NHR. However, how the colonization signal is and how systemic resistance to pathogens is developed is still unclear. In this study, we demonstrated that the extracellular polysaccharides (EPSs) of Bacillus cereus AR156 could act as novel microbe-associated molecular patterns (MAMPs) and function in the early perception status of the ISR of B. cereus AR156. The results revealed that B. cereus AR156 EPS could induce systemic resistance to Pst DC3000 in Arabidopsis. Cellular defense response markers such as hydrogen peroxide accumulation, callose deposition, and defense-associated enzyme were induced upon challenge inoculation in the leaves primed by EPS. Moreover, the defense-related genes PR1, PR2, and PR5 and mitogen-activated kinases (MAPK) cascade marker gene MPK6 were concurrently expressed in the leaves of EPS-treated plants and induced higher resistance to Pst DC3000 in Col-0 than that in the jar1 or etr1 mutants. The protection was absent in the NahG transgenic plants and npr1 mutant, suggesting an activation of the salicylic acid (SA)- and the MAPK-dependent signaling pathways with NPR1-dependent by B. cereus AR156 EPS. In conclusion, B. cereus AR156 EPS play an important role in MAMP perception during the process of rhizobacteria-triggered NHR. This study is the first to illustrate how AR156 induces systemic resistance to Pst DC3000 in Arabidopsis. It also provides the first explanation of how

  16. Bacillus cereus AR156 Extracellular Polysaccharides Served as a Novel Micro-associated Molecular Pattern to Induced Systemic Immunity to Pst DC3000 in Arabidopsis

    Science.gov (United States)

    Jiang, Chun-Hao; Fan, Zhi-Hang; Xie, Ping; Guo, Jian-Hua

    2016-01-01

    Non-host resistance (NHR) is a broad-spectrum plant defense. Upon colonizing on the surface on the root or leaves of non-host species, pathogens initial encounter preform and induce defense response in plant, such as induced hypersensitive response, PAMPs triggered immunity (PTI), and effector triggered immunity (ETI). The ability of plants to develop an induced systemic response (ISR) in reaction to the colonization by non-pathogenic rhizobacterium depends on interactions between host plants and the colonizing rhizobacterium, and the ISR also can be defined as a NHR. However, how the colonization signal is and how systemic resistance to pathogens is developed is still unclear. In this study, we demonstrated that the extracellular polysaccharides (EPSs) of Bacillus cereus AR156 could act as novel microbe-associated molecular patterns (MAMPs) and function in the early perception status of the ISR of B. cereus AR156. The results revealed that B. cereus AR156 EPS could induce systemic resistance to Pst DC3000 in Arabidopsis. Cellular defense response markers such as hydrogen peroxide accumulation, callose deposition, and defense-associated enzyme were induced upon challenge inoculation in the leaves primed by EPS. Moreover, the defense-related genes PR1, PR2, and PR5 and mitogen-activated kinases (MAPK) cascade marker gene MPK6 were concurrently expressed in the leaves of EPS-treated plants and induced higher resistance to Pst DC3000 in Col-0 than that in the jar1 or etr1 mutants. The protection was absent in the NahG transgenic plants and npr1 mutant, suggesting an activation of the salicylic acid (SA)- and the MAPK-dependent signaling pathways with NPR1-dependent by B. cereus AR156 EPS. In conclusion, B. cereus AR156 EPS play an important role in MAMP perception during the process of rhizobacteria-triggered NHR. This study is the first to illustrate how AR156 induces systemic resistance to Pst DC3000 in Arabidopsis. It also provides the first explanation of how

  17. Meeting staff representatives of the European Agencies

    CERN Multimedia

    Staff Association

    2014-01-01

      The AASC (Assembly of Agency Staff Committee) held its 27th Meeting of the specialized European Agencies on 26 and 27 May on the premises of the OHIM (Office for Harmonization in the Internal Market) in Alicante, Spain. Two representatives of the CERN Staff Association, in charge of External Relations, attended as observers. This participation is a useful complement to regular contacts we have with FICSA (Federation of International Civil Servants' Associations), which groups staff associations of the UN Agencies, and the annual CSAIO conferences (Conference of Staff Associations of International Organizations), where each Autumn representatives of international organizations based in Europe meet to discuss themes of common interest to better promote and defend the rights of the international civil servants. All these meetings allow us to remain informed on items that are directly or indirectly related to employment and social conditions of our colleagues in other international and Europ...

  18. Representative process sampling - in practice

    DEFF Research Database (Denmark)

    Esbensen, Kim; Friis-Pedersen, Hans Henrik; Julius, Lars Petersen;

    2007-01-01

    Didactic data sets representing a range of real-world processes are used to illustrate "how to do" representative process sampling and process characterisation. The selected process data lead to diverse variogram expressions with different systematics (no range vs. important ranges; trends and....../or periodicity; different nugget effects and process variations ranging from less than one lag to full variogram lag). Variogram data analysis leads to a fundamental decomposition into 0-D sampling vs. 1-D process variances, based on the three principal variogram parameters: range, sill and nugget effect....... The influence on the variogram from significant trends and outliers in the original data series receive special attention, due to their critical adverse effects. We highlight problem-dependent interpretation of variographic analysis a.o. the problem-dependent background for periodicities and trends. All...

  19. Growth stimulation of Bacillus cereus and Pseudomonas putida using nanostructured ZnO thin film as transducer element

    Energy Technology Data Exchange (ETDEWEB)

    Loukanov, Alexandre, E-mail: loukanov@mail.saitama-u.ac.jp [Saitama University, Department of Chemistry, Faculty of Science (Japan); Filipov, Chavdar [University of Forestry, Department of Infectious pathology, hygiene, technology and control of food stuffs of animal origin, Faculty of Veterinary Medicine (Bulgaria); Valcheva, Violeta [Bulgarian Academy of Science, Department of Infectious Diseases, Institute of microbiology (Bulgaria); Lecheva, Marta [University of Mining and Geology “St. Ivan Rilski”, Laboratory of Engineering NanoBiotechnology, Department of Engineering Geoecology (Bulgaria); Emin, Saim [University of Nova Gorica, Materials Research Laboratory (Slovenia)

    2015-04-15

    The semiconductor zinc oxide nanomaterial (ZnO or ZnO:H) is widely used in advanced biosensor technology for the design of highly-sensitive detector elements for various applications. In the attempt to evaluate its effect on common microorganisms, two types of nanostructured transducer films have been used (average diameter 600–1000 nm). They have been prepared by using both wet sol–gel method and magnetron sputtering. Their polycrystalline structure and specific surface features have been analyzed by X-ray diffraction (XRD), scanning electron microscope, and atomic force microscope. The assessment of growth stimulation of bacteria was determined using epifluorescent microscope by cell staining with Live/Dead BacLight kit. In our experiments, the growth stimulation of Gram-positive and Gram-negative bacteria on nanostructured ZnO film is demonstrated by Bacillus cereus and Pseudomonas putida. These two bacterial species have been selected, because they are well known and studied in biosensor technologies, with structural difference of their cell walls. These pathogens are easy for with common source in the liquid food or some commercial products. Our data has revealed that the method of transducer film preparation influences strongly bacterial inhibition and division. These results present the transforming signal precisely, when ZnO is used in biosensor applications.

  20. Identification and characterization of the endophytic plant growth prompter Bacillus Cereus strain mq23 isolated from Sophora Alopecuroides root nodules

    Directory of Open Access Journals (Sweden)

    Longfei Zhao

    2011-06-01

    Full Text Available Endophytes MQ23 and MQ23R isolated from Sophora alopecuroides root nodules were characterized by observing their ability to promote plant growth and employing molecular analysis techniques. Results showed that MQ23 and MQ23R are potential N2-fixing endophytes and belong to the same species as Bacillus cereus. MQ23 was shown to be able to produce siderophores, IAA, and demonstrate certain antifungal activity to plant pathogenic fungi. Co-inoculation with MQ23+MQ23II showed a more significant effect than inoculation alone in vitro for most of positive actions suggesting they have a cooperative interaction. Results of plant inoculation with endophytes indicated that the growth indexes of co-inoculated MQ23+MQ23II were higher than those of inoculated alone (p<0.05 (the exception being for root fresh weight when compared to negative control. There have been little of any studies of nonrhizobial putative endophytes with growth-promotion attributes in S. alopecuroides root nodules. This could be exploited as potential bio-inoculants and biocontrol agents in agriculture.

  1. Effects of Dissolved Oxygen Tension and Ammonium Concentration on Polyhydroxybutyrate Synthesis from Cassava Starch by Bacillus cereus IFO 13690

    Directory of Open Access Journals (Sweden)

    Margono .

    2015-11-01

    Full Text Available generated by an Adobe application 11.5606 Attempting to get low price of raw material for producing polyhydroxybutyrate is always studied. Tapioca starch is one of the raw material with low price. The objective of this research was to study the effects of initial ammonium concentration and dissolved oxygen tension (doT on producing PHB by Bacillus cereus IFO 13690 with tapioca starch as the carbon source. This fermentation was carried out in 5 L fementors with a 2 L working volume, temperature of 30 oC, and agitation of 500 rpm. The pH medium was controlled at 5.6 after it came down from the initial pH of 6.8. Meanwhile, the initial doT was 100 % air saturation and also came down to and maintained at doT of experiment, i.e. 1 , 5 , or 10 % air saturation. The best result was obtained when the initial ammonium concentration was 5 g/L and the doT value maintained at 5 % air saturation. By this conditions, the cell growth reached 5,457 g cell dry weight/L containing PHB of 2.42 % cell dry weigh after 29 hours fermentation. Normal 0 36 false false false

  2. Growth stimulation of Bacillus cereus and Pseudomonas putida using nanostructured ZnO thin film as transducer element

    International Nuclear Information System (INIS)

    The semiconductor zinc oxide nanomaterial (ZnO or ZnO:H) is widely used in advanced biosensor technology for the design of highly-sensitive detector elements for various applications. In the attempt to evaluate its effect on common microorganisms, two types of nanostructured transducer films have been used (average diameter 600–1000 nm). They have been prepared by using both wet sol–gel method and magnetron sputtering. Their polycrystalline structure and specific surface features have been analyzed by X-ray diffraction (XRD), scanning electron microscope, and atomic force microscope. The assessment of growth stimulation of bacteria was determined using epifluorescent microscope by cell staining with Live/Dead BacLight kit. In our experiments, the growth stimulation of Gram-positive and Gram-negative bacteria on nanostructured ZnO film is demonstrated by Bacillus cereus and Pseudomonas putida. These two bacterial species have been selected, because they are well known and studied in biosensor technologies, with structural difference of their cell walls. These pathogens are easy for with common source in the liquid food or some commercial products. Our data has revealed that the method of transducer film preparation influences strongly bacterial inhibition and division. These results present the transforming signal precisely, when ZnO is used in biosensor applications

  3. Decontamination of Streptococci biofilms and Bacillus cereus spores on plastic surfaces with DC and pulsed corona discharges

    Science.gov (United States)

    Koval'ová, Zuzana; Tarabová, Kataŕna; Hensel, Karol; Machala, Zdenko

    2013-02-01

    Cold air plasmas of DC and pulsed corona discharges: positive streamers and negative Trichel pulses were used for bio-decontamination of Streptococci biofilm and Bacillus cereus spores on polypropylene plastic surfaces. The reduction of bacterial population (evaluated as log10) in the biofilm on plastic surfaces treated by DC corona reached 2.4 logs with 10 min treatment time and 3.3 logs with 2 min treatment time with water spraying. The enhancement of plasma biocidal effects on the biofilm by electro-spraying of water through a hollow needle high-voltage electrode was investigated. No significant polarity effect was found with DC corona. Pulsed corona was demonstrated slightly more bactericidal for spores, especially in the negative polarity where the bacterial population reduction reached up to 2.2 logs at 10 min exposure time. Contribution to the Topical Issue "13th International Symposium on High Pressure Low Temperature Plasma Chemistry (Hakone XIII)", Edited by Nicolas Gherardi, Henryca Danuta Stryczewska and Yvan Ségui.

  4. Effects of methanol extract of Wedelia chinensis osbeck (asteraceae leaves against pathogenic bacteria with emphasise on Bacillus cereus

    Directory of Open Access Journals (Sweden)

    I Darah

    2013-01-01

    Full Text Available The antibacterial activity of the methanol extract of Wedelia chinensis leave was studied and tested against three pathogenic Gram positive bacteria (Bacillus cereus, B. subtilis and Stapylococcus aureus and three pathogenic Gram negative bacteria (Escherichia coli, Proteus rettgeri and Pseudomonas aeruginosa by the disk diffusion assay and broth dilution methods. The extract exhibited favourable antibacterial activity against the bacterial cells but was more potent against Gram positive bacteria with the minimum inhibition concentration of 3.12 to 6.25 mg/ml compared to the Gram negative bacteria which had minimum inhibition concentration values of 25 mg/ml. The time-kill study suggested that the extract possessed bactericidal properties at higher concentrations and eradicated the growth of bacterial cells. The major abnormalities occurred to the bacterial cells after exposed to the extract were complete alterations in their morphology and collapsed of the cells beyond repair. The methanol extract of W. chinensis may be an effective antibacterial agent to treat bacterial infections.

  5. Clarificação do extrato aquoso de Stevia rebaudiana (Bert. Bertoni utilizando o cacto, Cereus peruvianus

    Directory of Open Access Journals (Sweden)

    Larissa Maria Fernandes

    2001-05-01

    Full Text Available A tendência das indústrias que se preocupam em promover a saúde e prevenir doenças está em investir no desenvolvimento de tecnologias para produção de alimentos com baixas calorias e reduzido teor de gordura, mantendo suas qualidades nutricionais. Um dos estudos mais freqüentes é a substituição do açúcar por edulcorantes não calóricos, com a preocupação que estes substitutos sejam semelhantes em função organoléptica. Nas folhas da planta conhecida como Stevia rebaudiana (Bert. Bertoni (Asteraceae, ou simplesmente estévia, se encontram glicosídeos adoçantes (edulcorantes, como o esteviosídeo, rebaudiosídeos A, B, C, D, E e dulcosídeos A e B. Seu extrato aquoso apresenta-se em estado natural na cor marrom, o que o torna inconveniente para o consumidor usual. Neste trabalho, utilizou-se o cacto Cereus peruvianus como alternativa natural para a clarificação deste extrato. O cacto comportou-se como uma resina fortemente ácida e eliminou cerca de 95%, em média, a cor e turbidez do extrato de estévia

  6. Características físico-químicas e microbiológicas (Staphylococcus aureus e Bacillus cereus) da água e dos mexilhões cultivados na região de Ubatuba, SP Physical-chemistry characteristcs and microbiology (Staphylococcus aureus e Bacillus cereus) characteristics of the seawater and the cultivated mussels from Ubatuba, SP

    OpenAIRE

    Juliana Antunes Galvão; Érika Fabiane Furlan; Eduardo de O. Salán; Ernani Porto; Marília Oetterer

    2006-01-01

    Para efetivar o processamento dos mexilhões, o monitoramento da qualidade da matéria-prima compõe as exigências de qualidade para comercialização do produto. Objetivou-se com esta pesquisa diagnosticar parâmetros físico químicos e a incidência de S. aureus e B. cereus tanto na água de cultivo como no mexilhão. Na água do mar foram analisados pH e turbidez. Nos mexilhões, foram avaliados o pH e foi feito o exame biométrico das valvas. Foram realizadas análises de S. aureus e B. cereus tanto na...

  7. Quality of mussels cultivated and commercialized in Ubatuba, SP, Brazil: monitoration Bacillus cereus and Staphylococcus aureus growth after post-harvest processing Tratamento térmico de mexilhões Perna perna como forma de assegurar a qualidade: avaliação do crescimento de Bacillus cereus e de Staphylococcus aureus

    OpenAIRE

    Eduardo Oliveira Salán; Juliana Antunes Galvão; Érika Fabiane Furlan; Ernani Porto; Cláudio Rosa Gallo; Marília Oetterer

    2008-01-01

    Aiming at improving the quality of Perna perna mussels cultivated and commercialized in Ubatuba, SP, Brazil, the growth and elimination of Staphylococcus aureus and Bacillus cereus artificially inoculated in mussels were studied. The inoculation was carried out in "in natura" and pre-cooked mussels for 30 min, and after that the mussels were kept for 10 hours at room temperature (25 ± 1 °C) and under refrigeration (7 ± 1 °C). Six thermal treatments were evaluated: three ...

  8. Group cubization

    OpenAIRE

    Osajda, Damian

    2016-01-01

    We present a procedure of group cubization: It results in a group whose some features resemble the ones of a given group, and which acts without fixed points on a CAT(0) cubical complex. As a main application we establish lack of Kazhdan's property (T) for Burnside groups. Other applications include new constructions of non-exact groups.

  9. Seed reserve composition and mobilization during germination and early seedling establishment of Cereus jamacaru D.C. ssp. jamacaru (Cactaceae

    Directory of Open Access Journals (Sweden)

    Nara L.M. Alencar

    2012-09-01

    Full Text Available Cereus jamacaru, a Cactaceae found throughout northeast Brazil, is widely used as cattle food and as an ornamental and medicinal plant. However, there has been little information about the physiological and biochemical aspects involved in its germination. The aim of this study was to investigate its reserve mobilization during germination and early seedling growth. For this, C. jamacaru seeds were germinated in a growth chamber and collected at 0, 2, 4, 5, 6, 8 and 12 days after imbibition for morphological and biochemical analyses. Dry seeds had wrinkled seed coats and large, curved embryos. Lipids were the most abundant reserve, comprising approximately 55% and 65% of the dry mass for cotyledons and the hypocotylradicle axis, respectively. Soluble sugars and starch were the minor reserves, corresponding to approximately 2.2% of the cotyledons' dry mass, although their levels showed significant changes during germination. Soluble proteins corresponded to 40% of the cotyledons' dry mass, which was reduced by 81% at the final period of germination compared to dry seeds. C. jamacaru seed can be classified as an oil seed due to its high lipid content. Moreover, lipids were the main reserve mobilized during germination because their levels were strongly reduced after seed germination, while proteins were the second most utilized reserve in this process.Cereus jamacaru, uma cactácea encontrada comumente no nordeste brasileiro, é amplamente usada como planta forrageira e como ornamental e medicinal. No entanto, existem poucas informações sobre os aspectos fisiológicos e bioquímicos relacionados à sua germinação. O objetivo desse estudo foi avaliar a mobilização de reservas durante a germinação e o crescimento inicial de plântulas de C. jamacaru. Para isso, as sementes foram germinadas em câmaras de germinação e coletadas aos 0, 2, 4, 5, 6, 8 e 12 dias após a germinação para as análises fisiológicas e bioquímicas. As sementes

  10. Immunomodulatory effect of non-viable components of probiotic culture stimulated with heat-inactivated Escherichia coli and Bacillus cereus on holoxenic mice

    Directory of Open Access Journals (Sweden)

    L. M. Ditu

    2014-09-01

    Full Text Available Background: Competition of probiotic bacteria with other species from the intestinal microbiota involves different mechanisms that occur regardless of probiotics’ viability. The objective of this paper was to assess the cytokine serum levels in holoxenic mice after oral administration of non-viable components (NVC of Enterococcus faecium probiotic culture stimulated with heat-inactivated Escherichia coli and Bacillus cereus in comparison to NVC of unstimulated E. faecium probiotic culture. Methods: Probiotic E. faecium CMGb 16 culture, grown in the presence of heat-inactivated cultures of E. coli and B. cereus CMGB 102, was subsequently separated into supernatant (SN and heat-inactivated cellular sediment (CS fractions by centrifugation. Each NVC was orally administered to holoxenic mice (balb C mouse strain, in three doses, given at 24 hours. Blood samples were collected from the retinal artery, at 7, 14, and 21 days after the first administration of the NVC. The serum concentrations of IL-12 and tumor necrosis factor-alpha (TNF-α interleukins were assessed by ELISA method. Results: After the oral administration of SN component obtained from the probiotic culture stimulated with heat-inactivated cultures of B. cereus CMGB 102 and E. coli O28, the serum concentrations of IL-12 were maintained higher in the samples collected at 7 and 14 days post-administration. No specific TNF-α profile could be established, depending on stimulated or non-stimulated probiotic culture, NVC fraction, or harvesting time. Conclusion: The obtained results demonstrate that non-viable fractions of probiotic bacteria, stimulated by other bacterial species, could induce immunostimulatory effects mediated by cytokines and act, therefore, as immunological adjuvants.

  11. Cereulide formation by Bacillus weihenstephanensis and mesophilic emetic Bacillus cereus at temperature abuse depends on pre-incubation conditions

    DEFF Research Database (Denmark)

    Thorsen, Line; Budde, Birgitte Bjørn; Henrichsen, Lars;

    2009-01-01

    three strains produced considerably less cereulide. B. weihenstephanensis MC67 produced 100-6000 times less and the mesophilic B. cereus strains produced 9-40 times less cereulide. These results can partly be explained by differences in the growth at the temperature abuse. Effect of chill storage on...... cereulide production at temperature abuse has not been investigated previously. Results of the present study indicate that storage at 5 and 8 °C will not lead to emetic intoxications, however the time at, and choice of chill temperature will determine the amount of cereulide produced in a temperature abuse...

  12. Want change? Call your representative

    Science.gov (United States)

    Fischhoff, Ilya R.

    2011-07-01

    During my tenure as an AGU Congressional Science Fellow, which began in September 2010 and continues until November 2011, my time has been shared between working with the U.S. House of Representatives Natural Resource Committee Democratic staff and in the office of Rep. Ed Markey (D-Mass., ranking Democrat on the committee). I appreciate getting to work with staff, fellows, and interns who inspire me, make me laugh, and know their issues cold. Much of my work on the committee is related to fish, wildlife, oceans, lands, and water issues and is directly related to my background in ecology and evolutionary biology (I studied zebra ecology and behavior in Kenya). My assignments have included asking the Environmental Protection Agency (EPA) about why it has not changed the allowed usage of certain pesticides that the National Marine Fisheries Service has found to jeopardize the recovery of endangered Pacific salmon; helping to identify research needs and management options to combat the swiftly spreading and catastrophic white nose syndrome in North American bats; and inquiring as to whether a captive-ape welfare bill, if passed without amendment, could thwart development of a vaccine to stop the Ebola virus from continuing to cause mass mortality in endangered wild apes.

  13. Caracterização fenotípica e genotípica de Bacillus Cereus isolado em produtos lácteos com relação ao seu comportamento psicrotrófico

    OpenAIRE

    Montanhini, Maike Taís Maziero

    2012-01-01

    Resumo: Bacillus cereus é uma bactéria termodúrica, patogênica, formadora de esporos e capaz de se multiplicar em temperatura de refrigeração. Este micro-orcanismo pode causar defeitos tecnológicos em produtos lácteos, devido à formação de lipases e proteases. O presente trabalho teve como objetivo avaliar a ocorrência de B. cereus em amostras de produtos lácteos e caracterizar fenotípica e genotípicamente o comportamento psicrotrófico de isolados desta espécie. Para tanto, foram avaliadas 34...

  14. Feces derived allergens of Tyrophagus putrescentiae reared on dried dog food and evidence of the strong nutritional interaction between the mite and Bacillus cereus producing protease bacillolysins and exo-chitinases

    Directory of Open Access Journals (Sweden)

    Tomas eErban

    2016-02-01

    Full Text Available Tyrophagus putrescentiae (Schrank, 1781 is an emerging source of allergens in stored products and homes. Feces proteases are the major allergens of astigmatid mites (Acari: Acaridida. In addition, the mites are carriers of microorganisms and microbial adjuvant compounds that stimulate innate signaling pathways. We sought to analyze the mite feces proteome, proteolytic activities and mite-bacterial interaction in dry dog food. Proteomic methods comprising enzymatic and zymographic analysis of proteases and 2D-E-MS/MS were performed. The highest protease activity was assigned to trypsin-like proteases; lower activity was assigned to chymotrypsin-like proteases, and the cysteine protease cathepsin B-like had very low activity. The 2D-E-MS/MS proteomic analysis identified mite trypsin allergen Tyr p3, fatty acid-binding protein Tyr p13 and putative mite allergens ferritin (Grp 30 and (polyubiquitins. Tyr p3 was detected at different positions of the 2D-E. It indicates presence of zymogen at basic pI, and mature-enzyme form and enzyme fragment at acidic pI. Bacillolysins (neutral and alkaline proteases of Bacillus cereus symbiont can contribute to the protease activity of the mite extract. The bacterial exo-chitinases likely contribute to degradation of mite exuviae, mite bodies or food boluses consisting of chitin, including the peritrophic membrane. Thus, the chitinases disrupt the feces and facilitate release of the allergens. B. cereus was isolated and identified based on amplification and sequencing of 16S rRNA and motB genes. B. cereus was added into high-fat, high-protein (dry dog food and low-fat, low-protein (flour diets to 1% and 5% (w/w, and the diets palatability was evaluated in 21-day population growth test. The supplementation of diet with B. cereus significantly suppressed population growth and the suppressive effect was higher in the high-fat, high-protein diet than in the low-fat, low-protein food. Thus, B. cereus has to coexist

  15. Feces Derived Allergens of Tyrophagus putrescentiae Reared on Dried Dog Food and Evidence of the Strong Nutritional Interaction between the Mite and Bacillus cereus Producing Protease Bacillolysins and Exo-chitinases.

    Science.gov (United States)

    Erban, Tomas; Rybanska, Dagmar; Harant, Karel; Hortova, Bronislava; Hubert, Jan

    2016-01-01

    Tyrophagus putrescentiae (Schrank, 1781) is an emerging source of allergens in stored products and homes. Feces proteases are the major allergens of astigmatid mites (Acari: Acaridida). In addition, the mites are carriers of microorganisms and microbial adjuvant compounds that stimulate innate signaling pathways. We sought to analyze the mite feces proteome, proteolytic activities, and mite-bacterial interaction in dry dog food (DDF). Proteomic methods comprising enzymatic and zymographic analysis of proteases and 2D-E-MS/MS were performed. The highest protease activity was assigned to trypsin-like proteases; lower activity was assigned to chymotrypsin-like proteases, and the cysteine protease cathepsin B-like had very low activity. The 2D-E-MS/MS proteomic analysis identified mite trypsin allergen Tyr p3, fatty acid-binding protein Tyr p13 and putative mite allergens ferritin (Grp 30) and (poly)ubiquitins. Tyr p3 was detected at different positions of the 2D-E. It indicates presence of zymogen at basic pI, and mature-enzyme form and enzyme fragment at acidic pI. Bacillolysins (neutral and alkaline proteases) of Bacillus cereus symbiont can contribute to the protease activity of the mite extract. The bacterial exo-chitinases likely contribute to degradation of mite exuviae, mite bodies or food boluses consisting of chitin, including the peritrophic membrane. Thus, the chitinases disrupt the feces and facilitate release of the allergens. B. cereus was isolated and identified based on amplification and sequencing of 16S rRNA and motB genes. B. cereus was added into high-fat, high-protein (DDF) and low-fat, low-protein (flour) diets to 1 and 5% (w/w), and the diets palatability was evaluated in 21-day population growth test. The supplementation of diet with B. cereus significantly suppressed population growth and the suppressive effect was higher in the high-fat, high-protein diet than in the low-fat, low-protein food. Thus, B. cereus has to coexist with the mite in

  16. Working Group Versus Team Work

    OpenAIRE

    Valentina-Vasilica Zaharia; Mirela-Mihaela Dogaru; Dan-Marin Boaja

    2014-01-01

    The cell organization is represented by the working group and not the individual, groups that are a major feature of life organization. Quality circles were designed as tools for building team spirit in Japanese companies as a tool to enhance group cohesion and the training of employees. The essential characteristic of human behavior and organizational performance is given by the working group and the influence on group members, so members of the group leader should use in order to achieve a ...

  17. Group X

    Energy Technology Data Exchange (ETDEWEB)

    Fields, Susannah

    2007-08-16

    This project is currently under contract for research through the Department of Homeland Security until 2011. The group I was responsible for studying has to remain confidential so as not to affect the current project. All dates, reference links and authors, and other distinguishing characteristics of the original group have been removed from this report. All references to the name of this group or the individual splinter groups has been changed to 'Group X'. I have been collecting texts from a variety of sources intended for the use of recruiting and radicalizing members for Group X splinter groups for the purpose of researching the motivation and intent of leaders of those groups and their influence over the likelihood of group radicalization. This work included visiting many Group X websites to find information on splinter group leaders and finding their statements to new and old members. This proved difficult because the splinter groups of Group X are united in beliefs, but differ in public opinion. They are eager to tear each other down, prove their superiority, and yet remain anonymous. After a few weeks of intense searching, a list of eight recruiting texts and eight radicalizing texts from a variety of Group X leaders were compiled.

  18. The comER Gene Plays an Important Role in Biofilm Formation and Sporulation in both Bacillus subtilis and Bacillus cereus

    Science.gov (United States)

    Yan, Fang; Yu, Yiyang; Wang, Luyao; Luo, Yuming; Guo, Jian-hua; Chai, Yunrong

    2016-01-01

    Bacteria adopt alternative cell fates during development. In Bacillus subtilis, the transition from planktonic growth to biofilm formation and sporulation is controlled by a complex regulatory circuit, in which the most important event is activation of Spo0A, a transcription factor and a master regulator for genes involved in both biofilm formation and sporulation. In B. cereus, the regulatory pathway controlling biofilm formation and cell differentiation is much less clear. In this study, we show that a novel gene, comER, plays a significant role in biofilm formation as well as sporulation in both B. subtilis and B. cereus. Mutations in the comER gene result in defects in biofilm formation and a delay in spore formation in the two Bacillus species. Our evidence supports the idea that comER may be part of the regulatory circuit that controls Spo0A activation. comER likely acts upstream of sda, a gene encoding a small checkpoint protein for both sporulation and biofilm formation, by blocking the phosphor-relay and thereby Spo0A activation. In summary, our studies outlined a conserved, positive role for comER, a gene whose function was previously uncharacterized, in the regulation of biofilm formation and sporulation in the two Bacillus species. PMID:27446060

  19. Bactericidal Mechanism of Bio-oil Obtained from Fast Pyrolysis of Pinus densiflora Against Two Foodborne Pathogens, Bacillus cereus and Listeria monocytogenes.

    Science.gov (United States)

    Patra, Jayanta Kumar; Hwang, Hyewon; Choi, Joon Weon; Baek, Kwang-Hyun

    2015-06-01

    Foodborne bacteria are the leading cause of food spoilage and other related diseases. In the present study, the antibacterial activity of bio-oil (BO) manufactured by fast pyrolysis of pinewood sawdust (Pinus densiflora Siebold and Zucc.) against two disease-causing foodborne pathogens (Bacillus cereus and Listeria monocytogenes) was evaluated. BO at a concentration of 1000 μg/disc was highly active against both B. cereus (10.0-10.6 mm-inhibition zone) and L. monocytogenes (10.6-12.0-mm inhibition zone). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration values of BO were 500 and 1000 μg/mL, respectively, for both pathogens. At the MIC concentration, BO exhibited an inhibitory effect on the viability of the bacterial pathogens. The mechanism of action of BO revealed its strong impairing effect on the membrane integrity of bacterial cells, which was confirmed by a marked release of 260-nm absorbing material, leakage of electrolytes and K(+) ions, and reduced capacity for osmoregulation under high salt concentration. Scanning electron microscopy clearly showed morphological alteration of the cell membrane due to the effect of BO. Overall, the results of this study suggest that BO exerts effective antibacterial potential against foodborne pathogens and can therefore potentially be used in food processing and preservation. PMID:25928035

  20. Gene detection and toxin production evaluation of hemolysin BL of Bacillus cereus isolated from milk and dairy products marketed in Brazil

    Directory of Open Access Journals (Sweden)

    Andre L.S. Reis

    2013-12-01

    Full Text Available Bacillus cereusis an ubiquitous, spore-forming bacteria that can survive pasteurization and the majority of the heating processes used in the dairy industry. Besides, it is a pathogen responsible for different types of food poisoning. One type of foodborne disease caused by B.cereusis the diarrheal syndrome, which is caused by the ingestion of vegetative cells producing toxins in the small intestine. One virulence factor for the diarrheal syndrome is the toxin hemolysin BL (HBL, a three-component protein formed by the L1, L2 and B components. In order to evaluate the presence of diarrheal strains isolated from milk and dairy products, 63 B. cereus isolates were obtained from 260 samples of UHT milk, pasteurized milk and powdered milk, sold in commercial establishments and from different brands. The isolates were subjected to the Polymerase Chain Reaction (PCR for the detection of the encoding genes for the L1, L2 and B components and the toxin production capacity were evaluated with an immunoassay. A total of 23 [36.5%] isolates were identified carrying simultaneously the three tested genes, from which, 20 [86.9%] showed toxigenic capacity. 26 [41.3%] isolates did not carry any of genes tested and the other 14 [22.2%] were positive for one or two of them. The results showed a high toxigenic capacity among the B. cereus isolates able to produce the HBL, indicating a potential risk for consumers.