WorldWideScience

Sample records for cereus group organisms

  1. 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

  2. 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...

  3. 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.

  4. 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-...

  5. 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 ...

  6. 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.

  7. 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

  8. 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.

  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; 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....

  10. 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....

  11. 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...

  12. 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...

  13. 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....

  14. 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

  15. 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

  16. 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.

  17. 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...

  18. 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.

  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. 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...

  2. 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.

  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. 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...

  7. 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

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

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    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.

  9. 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....

  10. 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

  11. 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

  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.

    2010-01-01

    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

  13. 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

  14. 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.

  15. 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.

  16. 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

  17. 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

  18. 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...

  19. 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 ...

  20. 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.

  1. 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.

  2. ASPECTS ON ORGANIZED CRIMINAL GROUPS

    OpenAIRE

    Gheorghe-Iulian IONIŢĂ

    2014-01-01

    The author presents the concept of organized criminal group as defined in regional/international documents and in internal regulations, the incrimination of criminal groups in the Romanian legislation and some of the problems generated by the amendment to the criminal legislation and the entry into force of the new Criminal Code on the issue.

  3. 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...

  4. 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.

  5. 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.

  6. 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

  7. 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

  8. 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...

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. 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...

  14. 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.

  15. 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

  16. Organization of an undergraduate research group

    International Nuclear Information System (INIS)

    Traditionally, research groups consist of senior physicists, staff members, and graduate students. The physics department at Creighton University has formed a Relativistic Heavy Ion physics research group consisting primarily of undergraduate students. Although senior staff and graduate students are actively involved, undergraduate research and the education of undergraduates is the focus of the group. The presentation, given by two undergraduate members of the group, will outline progress made in the group's organization, discuss the benefits to the undergraduate group members, and speak to the balance which must be struck between education concerns and research goals

  17. 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...

  18. 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%

  19. 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

  20. 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.

  1. 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

  2. Comparison of resistance of biofilm and planktonic Bacillus cereus against organic acids and ethanol%蜡样芽孢杆菌及其生物被膜对有机酸及乙醇的抗性比较

    Institute of Scientific and Technical Information of China (English)

    李南薇; 杜冰; 杨公明; 余铭

    2013-01-01

    To compare the resistance of biofilm and planktonic cells of B. cereus to the environmental stresses, the effects of four organic acids (namely, acetic acid, citric acid, lactic acid, and malic acid), and ethanol on the cell survival were investigated in this paper. Upon 8% acetic acid treatment for 30 min, the survival of the cells in biofilms which were incubated for 24 h was found to be much higher than that of the planktonic bacteria cultured for the same period;besides, the planktonic bacteria in the stationary phase (incubation of 24 h) showed greater resistance to acetic acid treatment than those in the logarithmic phase (incubation of 4-12 h). The scanning electron microscopic analysis revealed that upon acetic acid treatment, the surfaces of the planktonic cells were markedly damaged, whereas those of the biofilm cells were only slightly damaged. Likewise, the biofilm cells were found to be more resistant than the planktonic cells in the presence of citric acid, lactic acid, malic acid, and ethanol; especially at higher concentrations (16%-20% for organic acids, and 50%-60% for ethanol), this phenomenon appeared to be more significant. Moreover, the planktonic cells in the stationary phase were more resistant to the environmental stresses tested than those in the logarithmic phase. Among the four organic acids and ethanol, malic acid showed the highest inhibitory activity against planktonic cells of B. cereus, while acetic acid was found to be the best for inhibition of biofilm cells. These findings suggested the risk of food spoilage by B. cereus biofilms, and demonstrated the importance of controlling its biofilms in the food industry. The results provided theoretic guidance for controlling the formation of biofilms and planktonic cells of B. cereus in the food industry.%为比较蜡样芽孢杆菌及其生物被膜对环境压力的抗性,该文主要研究了4种有机酸(乙酸、柠檬酸、乳酸和苹果酸)和乙醇对蜡样芽孢杆菌及

  3. Group Organized Project Work in Distance Education

    DEFF Research Database (Denmark)

    Helbo, Jan; Knudsen, Morten; Jensen, Lars Peter;

    2001-01-01

    Project organized problem based learning is a successful concept for on-campus education at Aalborg University. Recently this "Aalborg concept" has been used in networked distance education as well. This paper describes the experiences from two years of Internet-mediated project work in a new...... must communicate electronically, and that they are under a fierce time strain, studying part time and typically with a full time job and a family. In this paper, the main problems experienced with group organized project work in distance education are described, and some possible solutions are listed...... Master of Information Technology education. The main conclusions are, that the project work is a strong learning motivator, enhancing peer collaboration, for off-campus students as well. However, the concept cannot be directly transferred to off-campus learning. The main reasons are that the students...

  4. 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...

  5. 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

  6. 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

  7. 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...

  8. 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...

  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. 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.

  11. 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.

  12. 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...

  13. 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

  14. 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

  15. 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...

  16. 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...

  17. 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....

  18. 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...

  19. 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

  20. Zinc(II) Complexes with Dangling Functional Organic Groups

    OpenAIRE

    Yang, Jingxia; Puchberger, Michael; Qian, Renzhe; Maurer, Christian; Schubert, Ulrich

    2012-01-01

    Abstract Zinc(II) complexes with dangling functional organic groups were synthesized by reaction of zinc acetate with a series of bifunctional p-substituted benzene derivatives (a combination of carboxylate, oximate, amino, β-ketoimine, and salicylaldime groups). Selective coordination to carboxylate groups was observed when the second functional group was an oxime or β-ketoimine group. When the second group was an amine or salicylaldimine moiety, these groups were additionally coordinated. F...

  1. 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

  2. List, group or menu: Organizing Suggestions in Autocompletion Interfaces

    OpenAIRE

    Amin, Alia; Hildebrand, Michiel; Ossenbruggen, van, Jacco; Evers, V.; Hardman, Hazel Lynda

    2009-01-01

    We describe two user studies that investigate organization strategies of autocompletion in a known-item search task: searching for terms taken from a thesaurus. In Study 1, we explored ways of grouping term suggestions from two different thesauri (TGN and WordNet) and found that different thesauri may require different organization strategies. Users found Group organization more appropriate to organize location names from TGN, while Alphabetical works better for WordNet. In Study 2, we compar...

  3. Consumers’ grouping of organic and conventional food products

    DEFF Research Database (Denmark)

    Denver, Sigrid; Christensen, Tove

    2014-01-01

    A detailed account of the way consumers choose to group different varieties of organic and conventional food produce might have practical implications in terms of improved space management in supermarkets and better targeted promotions of organic products. The results presented here were obtained...... in a case study using a web-based questionnaire and 849 Danish consumers. The consumers were asked to group the contents of a virtual basket of organic and non-organic fruits and vegetables into two smaller baskets. A significant share of the consumers grouped the food products according to whether...

  4. A conciliation mechanism for self-organizing dynamic small groups.

    Science.gov (United States)

    Ren, Minglun; Hu, Zhongfeng; Jain, Hemant

    2016-01-01

    A group of individuals, organizations or things in internet of things (IoT) often dynamically self-organizes in small groups to accomplish certain tasks. This is common in virtual organization, social networks and the evolving field of IoT. These small groups have different behavioral characteristics than large groups. Members individually have some requirements and contribute some resources to the group. The organization and operation of such a group requires dynamic identification of group requirements that can be fulfilled by available resources and is approved by the group. We apply design science methods to develop an artifact that helps in conciliation of collective requirements and resources of small groups while maintaining each member's satisfaction. The mechanism also supports dynamic conciliation as members leave and new members join the group. Each member's requirement is specified as an explicit/implicit objective that is feasible/not feasible based on resources available to the group and whether the requirement is in alignment with other members' objectives. We validate the artifact by using it for a manufacturing service group and simulating the change in collective group requirements and resources as group membership changes dynamically. PMID:27390641

  5. Cooperative catalysis by silica-supported organic functional groups

    OpenAIRE

    Margelefsky, Eric L.; Zeidan, Ryan K.; Davis, Mark E.

    2008-01-01

    Hybrid inorganic–organic materials comprising organic functional groups tethered from silica surfaces are versatile, heterogeneous catalysts. Recent advances have led to the preparation of silica materials containing multiple, different functional groups that can show cooperative catalysis; that is, these functional groups can act together to provide catalytic activity and selectivity superior to what can be obtained from either monofunctional materials or homogeneous catalysts. This tutorial...

  6. 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

  7. 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).

  8. The new organization of the EDF Group; La nouvelle organisation du groupe EDF

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-01-18

    This paper presents the new organization of the EDF Group (Electricite De France), decided to improve the group performance. This new organization better integrates the international dimension. The management policy is discussed and the new head office is presented. (A.L.B.)

  9. 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...

  10. 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

  11. 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.

  12. 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

  13. 26 CFR 56.4911-7 - Affiliated group of organizations.

    Science.gov (United States)

    2010-04-01

    ... electing public charity's lobbying expenditures (as well as avoiding the $1,000,000 cap on a single... an affiliated group as a single organization for purposes of measuring both lobbying expenditures and... described in paragraph (a)(2) of this section, if one organization is able to control action on...

  14. 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

  15. 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

  16. Communication Network Integration and Group Uniformity in a Complex Organization.

    Science.gov (United States)

    Danowski, James A.; Farace, Richard V.

    This paper contains a discussion of the limitations of research on group processes in complex organizations and the manner in which a procedure for network analysis in on-going systems can reduce problems. The research literature on group uniformity processes and on theoretical models of these processes from an information processing perspective…

  17. 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

  18. 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.

  19. 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 ...

  20. 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

  1. 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

  2. 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.

  3. 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

  4. Single step signal group-imidazole labeling of organic phosphate groups under aqueous conditions

    International Nuclear Information System (INIS)

    Compounds and methods for single step, covalent labeling of the phosphate group of an organic substance under aqueous conditions are described. The labeling compound includes any kind of detectable signal group covalently bound to an imidazole moiety, which can be imidazole or a substituted imidazole. A preferred labeling compound has the formula shown in the accompanying diagram. 4 figs

  5. Single step signal group-imidazole labeling of organic phosphate groups under aqueous conditions

    Science.gov (United States)

    Giese, Roger W.; Wang, Poguang

    1996-01-01

    Compounds and methods for single step, covalent labeling of the phosphate group of an organic substance under aqueous conditions are described. The labeling compound includes any kind of detectable signal group covalently bound to an imidazole moiety, which can be imidazole or a substituted imidazole. A preferred labeling compound has the formula ##STR1##

  6. 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...

  7. Metal-Organic Frameworks Based on Main Group Metals

    OpenAIRE

    Zhao, Xiang

    2011-01-01

    Metal-organic frameworks (MOFs) represent a large family of crystalline porous materials which have been extensively studied during the past decade. Due to their great porosity, precise and uniform pore size and functional organic linkers, they have found applications in the area of gas storage, separation, ion-exchange, catalysis and sensors. While previous studies in this area emphasize more on transition metal based MOFs, the main group metal based MOFs have been relatively less explored, ...

  8. Development of web application for organizing work in smaller groups

    OpenAIRE

    Kerec, Žiga

    2015-01-01

    The purpose of this bachelor thesis was the development of an web application that would enable a smoother organization and prosecution of team work. It is intended to be used by members of smaller groups and can be described as a tool of communication that will improve the group’s organization. The application offers services for direct communication through discussions, file sharing and the division of current tasks. The server part of the application was created in the framework Django in ...

  9. 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

  10. 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

  11. 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

  12. Diversity attitudes and group knowledge processing in multicultural organizations

    DEFF Research Database (Denmark)

    Lauring, Jakob; Selmer, Jan

    2013-01-01

    The ability to locate, share, and use knowledge is vital for effective functioning of organizations. However, such knowledge processing can be complicated by increasing cultural diversity. Recent studies have suggested that a group’s diversity attitudes may increase group outcomes. In this study...

  13. 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.

  14. 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

  15. 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.

  16. 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

  17. Parameters for Organism Grouping - Gclust Server | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available Gclust Server Parameters for Organism Grouping Data detail Data name Parameters for Organism Grouping Descri... - Data analysis method - Number of data entries - Data item Description Field 1 Group number Field 2 Design...ated value for allocation to organism group Field 3 Group name Joomla SEF URLs by... | Contact Us Parameters for Organism Grouping - Gclust Server | LSDB Archive ...

  18. 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.

  19. Intergroup leadership in organizations: Leading across group and organizational boundaries

    OpenAIRE

    Hogg, Michael; Van Knippenberg, Daan; Rast, David E.

    2012-01-01

    textabstractIntergroup leadership-leadership of collaborative performance of different organizational groups or organizations-is associated with unique intergroup challenges that are not addressed by traditional leadership theories. To address this lacuna, we describe a theory of intergroup leadership. Firmly grounded in research on social identity and intergroup relations, the theory proposes that effective intergroup performance rests on the leader's ability to construct an intergroup relat...

  20. 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.

  1. 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

  2. Distributions of methyl group rotational barriers in polycrystalline organic solids

    Energy Technology Data Exchange (ETDEWEB)

    Beckmann, Peter A., E-mail: pbeckman@brynmawr.edu, E-mail: wangxianlong@uestc.edu.cn [Department of Physics, Bryn Mawr College, 101 North Merion Ave., Bryn Mawr, Pennsylvania 19010-2899 (United States); Conn, Kathleen G. [Department of Physics, Bryn Mawr College, 101 North Merion Ave., Bryn Mawr, Pennsylvania 19010-2899 (United States); Division of Education and Human Services, Neumann University, One Neumann Drive, Aston, Pennsylvania 19014-1298 (United States); Mallory, Clelia W. [Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323 (United States); Department of Chemistry, Bryn Mawr College, 101 North Merion Ave., Bryn Mawr, Pennsylvania 19010-2899 (United States); Mallory, Frank B. [Department of Chemistry, Bryn Mawr College, 101 North Merion Ave., Bryn Mawr, Pennsylvania 19010-2899 (United States); Rheingold, Arnold L. [Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Dr., La Jolla, California 92093-0358 (United States); Rotkina, Lolita [Regional Nanotechnology Facility, Laboratory for Research on the Structure of Matter, University of Pennsylvania, 3231 Walnut Street, Philadelphia, Pennsylvania 19104-6202 (United States); Wang, Xianlong, E-mail: pbeckman@brynmawr.edu, E-mail: wangxianlong@uestc.edu.cn [Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology, 4 North Jianshe Rd., 2nd Section, Chengdu 610054 (China)

    2013-11-28

    We bring together solid state {sup 1}H spin-lattice relaxation rate measurements, scanning electron microscopy, single crystal X-ray diffraction, and electronic structure calculations for two methyl substituted organic compounds to investigate methyl group (CH{sub 3}) rotational dynamics in the solid state. Methyl group rotational barrier heights are computed using electronic structure calculations, both in isolated molecules and in molecular clusters mimicking a perfect single crystal environment. The calculations are performed on suitable clusters built from the X-ray diffraction studies. These calculations allow for an estimate of the intramolecular and the intermolecular contributions to the barrier heights. The {sup 1}H relaxation measurements, on the other hand, are performed with polycrystalline samples which have been investigated with scanning electron microscopy. The {sup 1}H relaxation measurements are best fitted with a distribution of activation energies for methyl group rotation and we propose, based on the scanning electron microscopy images, that this distribution arises from molecules near crystallite surfaces or near other crystal imperfections (vacancies, dislocations, etc.). An activation energy characterizing this distribution is compared with a barrier height determined from the electronic structure calculations and a consistent model for methyl group rotation is developed. The compounds are 1,6-dimethylphenanthrene and 1,8-dimethylphenanthrene and the methyl group barriers being discussed and compared are in the 2–12 kJ mol{sup −1} range.

  3. 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

  4. Ozone-driven daytime formation of secondary organic aerosol containing carboxylic acid groups and alkane groups

    OpenAIRE

    Liu, S.; D. A. Day; J. E. Shields; L. M. Russell

    2011-01-01

    Carboxylic acids are present in substantial quantities in atmospheric particles, and they play an important role in the physical and chemical properties of aerosol particles. During measurements in coastal California in the summer of 2009, carboxylic acid functional groups were exclusively associated with a fossil fuel combustion factor derived from factor analysis of Fourier transform infrared spectroscopic measurements and closely correlated with oxygenated organic factors from aerosol mass...

  5. Ozone-driven daytime formation of secondary organic aerosol containing carboxylic acid groups and alkane groups

    Directory of Open Access Journals (Sweden)

    S. Liu

    2011-08-01

    Full Text Available Carboxylic acids are present in substantial quantities in atmospheric particles, and they play an important role in the physical and chemical properties of aerosol particles. During measurements in coastal California in the summer of 2009, carboxylic acid functional groups were exclusively associated with a fossil fuel combustion factor derived from factor analysis of Fourier transform infrared spectroscopic measurements and closely correlated with oxygenated organic factors from aerosol mass spectrometry measurements. The high fraction of acid groups and the high ratio of oxygen to carbon in this factor suggest that this factor is composed of secondary organic aerosol (SOA products of combustion emissions from the upwind industrial region (the ports of Los Angeles and Long Beach. Another indication of the photochemically-driven secondary formation of this combustion-emitted organic mass (OM was the daytime increase in the concentrations of acid groups and the combustion factors. This daytime increase closely tracked the O3 mixing ratio with a correlation coefficient of 0.7, indicating O3 was closely associated with the SOA maximum and thus likely the oxidant that resulted in acid group formation. Using a pseudo-Lagrangian framework to interpret this daytime increase of carboxylic acid groups and the combustion factors, we estimate that the carboxylic acid groups formed in a 12-h daytime period of one day ("Today's SOA" accounted for 25–33 % of the measured carboxylic acid group mass, while the remaining 67–75 % (of the carboxylic acid group mass was likely formed 1–3 days previously (the "Background SOA". A similar estimate of the daytime increase in the combustion factors suggests that "Today's SOA" and the "Background SOA" respectively contributed 25–50 % and 50–75 % of the combustion factor (the "Total SOA", for a "Total SOA" contribution to the OM of 60 % for the project average. Further, size

  6. 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

  7. 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...

  8. 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...

  9. 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...

  10. 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.

  11. Effect of group organization on the performance of cooperative processes

    CERN Document Server

    Reia, Sandro M

    2016-01-01

    Problem-solving competence at group level is influenced by the structure of the social networks and so it may shed light on the organization patterns of gregarious animals. Here we use an agent-based model to investigate whether the ubiquity of hierarchical networks in nature could be explained as the result of a selection pressure favoring problem-solving efficiency. The task of the agents is to find the global maxima of NK fitness landscapes and the agents cooperate by broadcasting messages informing on their fitness to the group. This information is then used to imitate, with a certain probability, the fittest agent in their influence networks. For rugged landscapes, we find that the modular organization of the hierarchical network with its high degree of clustering eases the escape from the local maxima, resulting in a superior performance as compared with the scale-free and the random networks. The optimal performance in a rugged landscape is achieved by letting the main hub to be only slightly more prop...

  12. 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.

  13. 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

  14. 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

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. 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...

  1. 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

  2. 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.

  3. 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

  4. 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%

  5. 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

  6. 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.

  7. 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

  8. 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

  9. 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

  10. 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

  11. Group Participation in the Organization: Social Loafing as a Limitation of Group Effectiveness.

    Science.gov (United States)

    Hallmark, James R.; Downs, Timothy M.

    Organizational studies traditionally take the position that the more people involved in group decision making the more ideas will be generated. Recent studies demonstrate that people have a tendency to "loaf" in group situations and thus decrease the level of effort exerted by individual group members. This paper first reviews the literature on…

  12. 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

  13. Toward a universal theory of the human group: sociological systems framework applied to the comparative analysis of groups and organizations

    OpenAIRE

    Tom R. Burns; Machado, Nora; Corte, Ugo

    2014-01-01

    Drawing on a sociological multi-level, dynamic systems approach – actor-system-dynamics (ASD) -- which has been developed and applied in institutional, organizational, and societal analyses, we formulate a general model for the comparative analysis of social groups and organizations. This social systems approach has not been previously applied in the group area. We claim that the approach can be systematically and fruitfully applied to small as well as large groups and organiza...

  14. Prediction of crystal densities of organic explosives by group additivity

    Energy Technology Data Exchange (ETDEWEB)

    Stine, J R

    1981-08-01

    The molar volume of crystalline organic compound is assumed to be a linear combination of its constituent volumes. Compounds consisting only of the elements hydrogen, carbon, nitrogen, oxygen, and fluorine are considered. The constituent volumes are taken to be the volumes of atoms in particular bonding environments and are evaluated from a large set of crystallographic data. The predicted density has an expected error of about 3%. These results are applied to a large number of explosives compounds.

  15. Drafting organic Food Regulations: The Case for Incorporating Congressional Intent and Interest Group Commentary

    OpenAIRE

    Dungey, Elizabeth A.

    1999-01-01

    The scope of the organic food debate has embroiled more constituents than simply consumers and producers of organic food. At each step along the way various interest groups such as small organic farmers, private organic certifiers, politicians, international community members, large agri-business lobbyists, environmental groups, consumers and general taxpayers have all added their voices to the debate. The USDA and other parties instrumental to the ongoing drafting of regulations for the Nati...

  16. A centralized global automation group in a decentralized organization

    OpenAIRE

    Jeffrey Veitch; Judy Hinderliter-Smith; James Ormand; Jimmy Bruner; Larry Birkemo

    2000-01-01

    In the latter part of the 1990s, many companies have worked to foster a ‘matrix’ style culture through several changes in organizational structure. This type of culture facilitates communication and development of new technology across organizational and global boundaries. At Glaxo Wellcome, this matrix culture is reflected in an automation strategy that relies on both centralized and decentralized resources. The Group Development Operations Information Systems Robotics Team is a centralized ...

  17. Self-organization in a group of mobile autonomous agents

    OpenAIRE

    Long WANG

    2004-01-01

    This paper considers a discrete time swarm model of a group of mobile autonomous agents with a simple attraction and repulsion function for swarm aggregation and investigates its stability properties. In particular, it is proved that the individuals (members) of the swarm will aggregate and form a cohesive cluster of a finite size depending only on the parameters of the swarm model in a finite time, and the swarm system is completely stable.

  18. THE FORMATION OF CONSCIENCE AND MANAGEMENT GROUPS IN ORGANIZATIONS

    Directory of Open Access Journals (Sweden)

    Neisa Maria, Martins da Cunha

    2010-01-01

    Full Text Available This paper presents theoretical proposals, as the Theory of Human Relations, especially the Theory of Group Dynamics and the Conscience Formation, which promote understanding and support for the conduct of the leaders in team management, aiming at a route suitable for questions, reflections, enabling new perceptions of self-consciousness, as Hegel says. It is worth highlighting that through these considerations, it becomes possible to conduct more realistic impacts triggered in the organizational culture, as from a better management of interpersonal relationships within teams, these teams have a training goal or not.

  19. Resource limitation drives spatial organization in microbial groups.

    Science.gov (United States)

    Mitri, Sara; Clarke, Ellen; Foster, Kevin R

    2016-06-01

    Dense microbial groups such as bacterial biofilms commonly contain a diversity of cell types that define their functioning. However, we have a limited understanding of what maintains, or purges, this diversity. Theory suggests that resource levels are key to understanding diversity and the spatial arrangement of genotypes in microbial groups, but we need empirical tests. Here we use theory and experiments to study the effects of nutrient level on spatio-genetic structuring and diversity in bacterial colonies. Well-fed colonies maintain larger well-mixed areas, but they also expand more rapidly compared with poorly-fed ones. Given enough space to expand, therefore, well-fed colonies lose diversity and separate in space over a similar timescale to poorly fed ones. In sum, as long as there is some degree of nutrient limitation, we observe the emergence of structured communities. We conclude that resource-driven structuring is central to understanding both pattern and process in diverse microbial communities. PMID:26613343

  20. 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.

  1. 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

  2. Democratic elements in group and project organized PBL

    DEFF Research Database (Denmark)

    Qvist, Palle

    2006-01-01

    Students in a democratic learning system as the Aalborg Model knows of and uses democratics skills as e.g. the ability to discuss and accept other points of view, negotiate, compromise, reach consensus or accept the result of a vote in striving to reach specific common or personal learning goals...... beyond it to the school and the community” (Marris, 2003:274) then implementing democratic learning systems as The Aalborg Model are important for supporting and promote democratic bildung of students in higher education. This article defines at a – start - what should be understood by a democratic...... learning system. It contrasts it to an authoritarian or elitist systems. Then it brings the results from an investigation of 9 process analyses’ written at the end of the second semester 2005 by project groups from The Technical Natural Scientific Basic Year at Aalborg University and concludes that...

  3. 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...

  4. 7 CFR 340.2 - Groups of organisms which are or contain plant pests and exemptions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Groups of organisms which are or contain plant pests... AND PRODUCTS ALTERED OR PRODUCED THROUGH GENETIC ENGINEERING WHICH ARE PLANT PESTS OR WHICH THERE IS REASON TO BELIEVE ARE PLANT PESTS § 340.2 Groups of organisms which are or contain plant pests...

  5. Organized crime and group-based ideology: The association between masculine honor and collective opposition against criminal organizations

    OpenAIRE

    Travaglino, Giovanni A.; Abrams, Dominic; Randsley de Moura, Georgina; Russo, Giuseppina

    2014-01-01

    What is the role of culture in establishing young people’s pathways into gang membership? Italian criminal organizations (COs) exhibit adherence to codes of honor and masculinity, important values in the context where they originated. Here it is proposed that the embedding of these values at an individual level may lessen young people’s group-based opposition to such organizations, and indirectly, create a space in which such organizations can persist and recruit. In a study of young Southern...

  6. 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...

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. 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°

  12. [Identification in organizations and its relationship with prototypicality and conflict between organizational groups].

    Science.gov (United States)

    Yubero, Santiago; Morales, J Francisco

    2006-08-01

    The scope and nature of the identification process of 282 workers representative of an important professional group of a university organization is analyzed in an attempt to ascertain if they identify mainly with their organization as a whole or with their professional group. A strong rivalry between the group object of the study and another professional group of the same organization manifests itself through a remarkable differentiation of group prototypes, which precludes the possibility of an overarching, supraordinate organizational identification. In addition, the degree of group prototypicality is related to the intensity of the negative attitude toward the rival group and can be taken as a predictor of a likely intra-organizational conflict. PMID:17296063

  13. 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.

  14. 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

  15. 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.

  16. Edge-Region Grouping in Figure-Ground Organization and Depth Perception

    OpenAIRE

    Palmer, Stephen E.; Brooks, Joseph L.

    2008-01-01

    Edge-region grouping (ERG) is proposed as a unifying and previously unrecognized class of relational information that influences figure-ground organization and perceived depth across an edge. ERG occurs when the edge between two regions is differentially grouped with one region based on classic principles of similarity grouping. The ERG hypothesis predicts that the grouped side will tend to be perceived as the closer, figural region. Six experiments are reported that test the predictions of t...

  17. Inter-group aggression: the multi-individual organism and the survival instinct.

    Science.gov (United States)

    Hughes-Jones, N

    2000-01-01

    Inter-group aggression, carried out at the level of the in-groups and out-groups of ethnocentric theory, continued unabated throughout the twentieth century. Its frequency, together with its ferocity, indicates a potent biological cause. We have evolved as social animals, and it is postulated that evolution has proceeded to such an extent that 'multi-individual social organisms', that is, 'social groups that fight each other are self-sustaining, self-replicating whole containing interdependent parts'. This results from the total integration of individuals into the social structure and culture of the in-group; individuals are inseparable from their society and evidence for this proposal is given. Cohesion is given through the collective consciousness and collective memory. The analogy is to multicellular organisms that evolved from the association of single cell organisms. All biological organisms are subject to the survival instinct, which is thus the potent biological cause of inter-group aggression. Groups compete for territory and see other groups as a threat. Prevention of inter-group aggression should come from the insight that threatening behaviour endangers the integrity of the society of out-groups, initiating conflict. PMID:10893943

  18. Ion-selective electrodes in organic elemental and functional group analysis: a review

    Energy Technology Data Exchange (ETDEWEB)

    Selig, W.

    1977-11-08

    The literature on the use of ion-selective electrodes in organic elemental and functional group analysis is surveyed in some detail. The survey is complete through Chemical Abstracts, Vol. 83 (1975). 40 figures, 52 tables, 236 references.

  19. Ion-selective electrodes in organic elemental and functional group analysis: a review

    International Nuclear Information System (INIS)

    The literature on the use of ion-selective electrodes in organic elemental and functional group analysis is surveyed in some detail. The survey is complete through Chemical Abstracts, Vol. 83 (1975). 40 figures, 52 tables, 236 references

  20. Functional group composition of ambient and source organic aerosols determined by tandem mass spectrometry

    Directory of Open Access Journals (Sweden)

    J. Dron

    2010-04-01

    Full Text Available The functional group composition of various organic aerosols (OA is being investigated using a recently developed analytical approach based on atmospheric pressure chemical ionisation-tandem mass spectrometry (APCI-MS/MS. The determinations of the three functional groups' contents are performed quantitatively by neutral loss (carboxylic and carbonyl groups and precursor ion (nitro groups scanning modes of a tandem mass spectrometer. Major organic aerosol sources are studied: vehicular emission and wood combustion for primary aerosol sources; and a secondary organic aerosol (SOA produced through photo-oxidation of o-xylene. The results reveal significant differences in the functional group contents of these source aerosols. The laboratory generated SOA is dominated by carbonyls while carboxylics are preponderate in the wood combustion particles. On the other hand, vehicular emissions are characterised by a strong nitro content. The total amount of the three functional groups accounted for 1.7% (vehicular to 13.5% (o-xylene photo-oxidation of the organic carbon. The diagnostic functional group ratios are then used to tentatively differentiate sources of particles collected in an urban background environment located in an Alpine valley (Chamonix, France during a strong winter pollution event. The three functional groups under study account for a total functionalisation rate of 2.2 to 3.8% of the organic carbon in this ambient aerosol, which is also dominated by carboxylic moieties. In this particular case study of a deep alpine valley during winter, we show that the nitro- and carbonyl-to-carboxylic diagnostic ratios can be a useful tool to distinguish the sources. In these conditions, the total OA concentrations are highly dominated by wood combustion OA. This result is confirmed by an organic markers source apportionment approach which assesses a wood burning organic carbon contribution of about 60%. Finally, examples of functional group mass

  1. The Exploration of the Relationship between Participation in Organized Activity and Cross-Group Friendships

    Directory of Open Access Journals (Sweden)

    Wonseok Suh

    2011-12-01

    Full Text Available Cross-group friendship is an important element in regard to reducing prejudice and increasing positive interracial interactions among young adults. In order to facilitate the formation of cross-group friendships, organized activity participation (e.g., community service and school-based extracurricular activities may provide an environment that supports positive cross-cultural interactions and contacts. The sample used for this study consisted of 601 college students. We tested whether participation in an organized activity contributes to the formation of cross-group friendships. The results of this study indicate that community service and school-based extracurricular activities significantly contribute to the formation of cross-group friendships among young adults. The findings also suggest that a variety of organized activities should be developed and implemented to facilitate cross-group friendships. We also discuss the practical implications of these findings.

  2. Chemkarta: A Card Game for Teaching Functional Groups in Undergraduate Organic Chemistry

    Science.gov (United States)

    Knudtson, Christopher A.

    2015-01-01

    Students in undergraduate organic chemistry courses are frequently overwhelmed by the volume and complexity of information they are expected to learn. To aid in students' learning of organic functional groups, a novel card game "ChemKarta" is reported that can serve as a useful alternative to flashcards. This pedagogy is a simple…

  3. 26 CFR 56.4911-10 - Members of a limited affiliated group of organizations.

    Science.gov (United States)

    2010-04-01

    ... governing instruments of O and P, any decision made by N on national legislative issues (such as issues... governing instrument, bound by decisions of one or more of the other such members on legislative issues other than national legislative issues. Each organization in a group of organizations that satisfies...

  4. Pattern classification and recognition of invertebrate functional groups using self-organizing neural networks.

    Science.gov (United States)

    Zhang, WenJun

    2007-07-01

    Self-organizing neural networks can be used to mimic non-linear systems. The main objective of this study is to make pattern classification and recognition on sampling information using two self-organizing neural network models. Invertebrate functional groups sampled in the irrigated rice field were classified and recognized using one-dimensional self-organizing map and self-organizing competitive learning neural networks. Comparisons between neural network models, distance (similarity) measures, and number of neurons were conducted. The results showed that self-organizing map and self-organizing competitive learning neural network models were effective in pattern classification and recognition of sampling information. Overall the performance of one-dimensional self-organizing map neural network was better than self-organizing competitive learning neural network. The number of neurons could determine the number of classes in the classification. Different neural network models with various distance (similarity) measures yielded similar classifications. Some differences, dependent upon the specific network structure, would be found. The pattern of an unrecognized functional group was recognized with the self-organizing neural network. A relative consistent classification indicated that the following invertebrate functional groups, terrestrial blood sucker; terrestrial flyer; tourist (nonpredatory species with no known functional role other than as prey in ecosystem); gall former; collector (gather, deposit feeder); predator and parasitoid; leaf miner; idiobiont (acarine ectoparasitoid), were classified into the same group, and the following invertebrate functional groups, external plant feeder; terrestrial crawler, walker, jumper or hunter; neustonic (water surface) swimmer (semi-aquatic), were classified into another group. It was concluded that reliable conclusions could be drawn from comparisons of different neural network models that use different distance

  5. Organ weight: As Influenced by color, sex and weight group in Japanese quail

    Directory of Open Access Journals (Sweden)

    R. Tarhyel

    2012-08-01

    Full Text Available This study was carried out on Japanese quails (Coturnix japonica to determine the effect of sex, colour and weight group on various organ weights. The birds were housed in deep litter pen at the poultry unit of University of Maiduguri Teaching and Research Farm. Birds were fed with broiler starter marsh from 5-8 weeks then, layer mash from 8-52 weeks. The birds were divided into various groups (sex, colour and weight groups. The experiment lasted for 52 weeks. Birds were slaughtered and eviscerated. The organs were weighed using sensitive scale and the results obtained were subjected to statistical analysis using Analysis of Variance (SPSS 16.0 statistical package and the means were separated using Duncan Multiple Range Test. Effect of color on organ weight were statistically not significant (p>0.05 except for fat weight, while the effect of sex on organ weight indicated that male and female differed significantly (p

  6. Managing the conflict between individual needs and group interests--ethical leadership in health care organizations.

    Science.gov (United States)

    Shale, Suzanne

    2008-03-01

    This paper derives from a grounded theory study of how Medical Directors working within the UK National Health Service manage the moral quandaries that they encounter as leaders of health care organizations. The reason health care organizations exist is to provide better care for individuals through providing shared resources for groups of people. This creates a paradox at the heart of health care organization, because serving the interests of groups sometimes runs counter to serving the needs of individuals. The paradox presents ethical dilemmas at every level of the organization, from the boardroom to the bedside. Medical Directors experience these organizational ethical dilemmas most acutely by virtue of their position in the organization. As doctors, their professional ethic obliges them to put the interests of individual patients first. As executive directors, their role is to help secure the delivery of services that meet the needs of the whole patient population. What should they do when the interests of groups of patients, and of individual patients, appear to conflict? The first task of an ethical healthcare organization is to secure the trust of patients, and two examples of medical ethical leadership are discussed against this background. These examples suggest that conflict between individual and population needs is integral to health care organization, so dilemmas addressed at one level of the organization inevitably re-emerge in altered form at other levels. Finally, analysis of the ethical activity that Medical Directors have described affords insight into the interpersonal components of ethical skill and knowledge. PMID:18382123

  7. 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.

  8. 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.

  9. Fourier Transform Infrared Spectroscopy for Identification and Quantification of Organic Functional Groups in Aqueous Phase Secondary Organic Aerosol

    Science.gov (United States)

    George, K.; Ruthenburg, T. C.; Smith, J.; Anastasio, C.; Dillner, A. M.

    2011-12-01

    Particles in the atmosphere influence visibility, climate, and human health. Secondary organic aerosols (SOA) formed from chemical reactions in the atmosphere constitute a portion of total organic particle mass. Most research on SOA has focused on gas phase reactions; however, reactions taking place in cloud and fog drops may be significant. One group of water-soluble compounds that participate in these reactions is phenols. Phenols, emitted from biomass burning, react in the aqueous phase to form low-volatility SOA products. The products formed from these reactions are currently poorly characterized. In order to characterize laboratory-generated samples, we are developing an attenuated total reflectance-Fourier transform infrared spectroscopic (ATR-FTIR) technique to identify and quantify organic functional groups in SOA. Aqueous SOA is made in the laboratory by illuminating solutions of phenolic compounds with an oxidant. The illuminated solution is then blown to dryness in order to determine the mass of SOA produced. The dry SOA is reconstituted in water and drops of this solution are placed onto a single-reflection ATR accessory. In order to identify and quantify functional groups in the complex SOA samples, it is necessary to calibrate with compounds and mixtures of compounds containing bond types similar to those found in the laboratory-generated SOA. Initially, focus has been placed on multiple peaks located in the region between 1800 cm-1 and 800 cm-1, including peaks for C=O and C-O. We distinguish between characteristic absorbances to begin determining the organic functional group composition of the SOA samples. This ATR-FTIR technique complements information from mass spectrometry measurements and allows us to quantify organic mass for non-volatile SOA products.

  10. Prediction of cloud condensation nuclei activity for organic compounds using functional group contribution methods

    Science.gov (United States)

    Petters, M. D.; Kreidenweis, S. M.; Ziemann, P. J.

    2016-01-01

    A wealth of recent laboratory and field experiments demonstrate that organic aerosol composition evolves with time in the atmosphere, leading to changes in the influence of the organic fraction to cloud condensation nuclei (CCN) spectra. There is a need for tools that can realistically represent the evolution of CCN activity to better predict indirect effects of organic aerosol on clouds and climate. This work describes a model to predict the CCN activity of organic compounds from functional group composition. Following previous methods in the literature, we test the ability of semi-empirical group contribution methods in Köhler theory to predict the effective hygroscopicity parameter, kappa. However, in our approach we also account for liquid-liquid phase boundaries to simulate phase-limited activation behavior. Model evaluation against a selected database of published laboratory measurements demonstrates that kappa can be predicted within a factor of 2. Simulation of homologous series is used to identify the relative effectiveness of different functional groups in increasing the CCN activity of weakly functionalized organic compounds. Hydroxyl, carboxyl, aldehyde, hydroperoxide, carbonyl, and ether moieties promote CCN activity while methylene and nitrate moieties inhibit CCN activity. The model can be incorporated into scale-bridging test beds such as the Generator of Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A) to evaluate the evolution of kappa for a complex mix of organic compounds and to develop suitable parameterizations of CCN evolution for larger-scale models.

  11. Working with Organized Groups. Section 2, Improving Your School-Community Relations Program. Successful School Administration Series.

    Science.gov (United States)

    Fusco, Gene C.

    Working with organized groups can be an effective way of improving school-community relations. Under proper conditions two types of organized efforts have proved to be successful -- parent-teacher groups and citizens' committees for better schools. Basic to the wise use of organized citizens groups is the need for the school staff to have…

  12. Estimation of Formation Enthalpies of Organic Pollutants from a New Structural Group Contribution Method

    Institute of Scientific and Technical Information of China (English)

    Mehdi Bagheri; Afshin Bakhtiari; Masoume Jaberi

    2013-01-01

    Chemical stability and reactivity of organic pollutants is dependent to their formation enthalpies.The main objective of this study is to provide simple straightforward strategy for prediction of the formation enthalpies of wide range organic pollutants only from their structural functional groups.Using such an extended dataset comprising 1694 organic chemicals from 77 diverse material classes benefits the generalizability and reliability of the study.The new suggested collection of 12 functional groups and a simple linear regression lead to promising statistics of R2=0.958,Q2Loo =0.956,and δAEE=57 kJ·mol-1 for the whole dataset.Moreover,unknown experimental formation enthalpies for 27 organic pollutants are estimated by the presented approach.The resultant model needs no technical software/calculations,and thus can be easily applied by a non-specialist user.

  13. A Framework for Exploring the Dynamics of Autonomous Work Groups in Manufacturing Organizations

    Institute of Scientific and Technical Information of China (English)

    Joseph; W; K; Chan; W; B; Lee

    2002-01-01

    Nowadays, new paradigm of enterprise organization i s constantly changing due to the emergence of the global marketplace, the rise of information technology, and the emphasis of the social developments. This re quires a more flexible form of organization that are more adaptable to rapid cha nges in business environment such as autonomous work groups (AWGs) in order to achieve higher productivity and effectiveness. AWGs are work units responsib le for the production of goods and the provision of servi...

  14. Soft Skills: An Important Asset Acquired from Organizing Regional Student Group Activities

    OpenAIRE

    De Ridder, J.; Meysman, P.; Oluwagbemi, O.; Abeel, T.

    2014-01-01

    Contributing to a student organization, such as the International Society for Computational Biology Student Council (ISCB-SC) and its Regional Student Group (RSG) program, takes time and energy. Both are scarce commodities, especially when you are trying to find your place in the world of computational biology as a graduate student. It comes as no surprise that organizing ISCB-SC-related activities sometimes interferes with day-to-day research and shakes up your priority list. However, we una...

  15. 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.)

  16. Estimation of Properties of Pure Organic Substances with Group and Pair Contributions

    Directory of Open Access Journals (Sweden)

    J.E.S. Ourique

    1997-06-01

    Full Text Available ABSTRACTbstract - This work presents a new predictive method for the estimation of properties of pure organic substances. Each compound is assigned a molecular graph or an adjacency matrix representing its chemical structure, from which properties are then obtained as a summation of all contributions associated with functional groups and chemically bonded pairs of groups. The proposed technique is applied to the estimation of critical temperature, critical pressure, critical volume and normal boiling point of 325 organic compounds from different chemical species. Accurate predictions based solely on chemical structure are obtained

  17. 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...

  18. 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...

  19. 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...

  20. Functional group composition of ambient and source organic aerosols determined by tandem mass spectrometry

    International Nuclear Information System (INIS)

    The functional group composition of various organic aerosols (OA) is investigated using a recently developed analytical approach based on atmospheric pressure chemical ionisation-tandem mass spectrometry (APCIMS/MS). The determinations of three functional groups contents are performed quantitatively by neutral loss (carboxylic and carbonyl groups, R-COOH and R-CO-R' respectively) and precursor ion (nitro groups, R-NO2) scanning modes of a tandem mass spectrometer. Major organic aerosol sources are studied: vehicular emission and wood combustion for primary aerosol sources; and a secondary organic aerosol (SOA) produced through photooxidation of o-xylene. The results reveal significant differences in the functional group contents of these source aerosols. The laboratory generated SOA is dominated by carbonyls while carboxylics are preponderate in the wood combustion particles. On the other hand, vehicular emissions are characterised by a strong nitro content. The total amount of the three functional groups accounts for 1.7% (vehicular) to 13.5% (o-xylene photooxidation) of the organic carbon. Diagnostic functional group ratios are then used to tentatively discriminate sources of particles collected in an urban background environment located in an Alpine valley (Chamonix, France) during a strong winter pollution event. The three functional groups under study account for a total functionalization rate of 2.2 to 3.8% of the organic carbon in this ambient aerosol, which is also dominated by carboxylic moieties. In this particular case study of a deep alpine valley during winter, we show that the nitro- and carbonyl-to-carboxylic diagnostic ratios can be a useful tool to discriminate sources. In these conditions, the total OA concentrations are highly dominated by wood combustion OA. This result is confirmed by an organic markers source apportionment approach which assess a wood burning organic carbon contribution of about 60%. Finally, examples of functional group mass

  1. Functional group composition of ambient and source organic aerosols determined by tandem mass spectrometry

    Directory of Open Access Journals (Sweden)

    J. Dron

    2010-08-01

    Full Text Available The functional group composition of various organic aerosols (OA is investigated using a recently developed analytical approach based on atmospheric pressure chemical ionisation-tandem mass spectrometry (APCI-MS/MS. The determinations of three functional groups contents are performed quantitatively by neutral loss (carboxylic and carbonyl groups, R-COOH and R-CO-R´ respectively and precursor ion (nitro groups, R-NO2 scanning modes of a tandem mass spectrometer. Major organic aerosol sources are studied: vehicular emission and wood combustion for primary aerosol sources; and a secondary organic aerosol (SOA produced through photooxidation of o-xylene. The results reveal significant differences in the functional group contents of these source aerosols. The laboratory generated SOA is dominated by carbonyls while carboxylics are preponderate in the wood combustion particles. On the other hand, vehicular emissions are characterised by a strong nitro content. The total amount of the three functional groups accounts for 1.7% (vehicular to 13.5% (o-xylene photooxidation of the organic carbon. Diagnostic functional group ratios are then used to tentatively discriminate sources of particles collected in an urban background environment located in an Alpine valley (Chamonix, France during a strong winter pollution event. The three functional groups under study account for a total functionalisation rate of 2.2 to 3.8% of the organic carbon in this ambient aerosol, which is also dominated by carboxylic moieties. In this particular case study of a deep alpine valley during winter, we show that the nitro- and carbonyl-to-carboxylic diagnostic ratios can be a useful tool to discriminate sources. In these conditions, the total OA concentrations are highly dominated by wood combustion OA. This result is confirmed by an organic markers source apportionment approach which assess a wood burning organic carbon contribution of about 60

  2. Functional group composition of ambient and source organic aerosols determined by tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Dron, J.; El Haddad, I.; Temime-Roussel, B.; Wortham, H.; Marchand, N. [Univ Aix Marseille, CNRS, Lab Chim Provence, Equipe Instrumentat and React Atmospher, UMR 6264, F-13331 Marseille 3 (France); Jaffrezo, J.L. [Univ Grenoble 1, CNRS, UMR 5183, Lab Glaciol and Geophys Environm, F-38402 St Martin Dheres (France)

    2010-07-01

    The functional group composition of various organic aerosols (OA) is investigated using a recently developed analytical approach based on atmospheric pressure chemical ionisation-tandem mass spectrometry (APCIMS/MS). The determinations of three functional groups contents are performed quantitatively by neutral loss (carboxylic and carbonyl groups, R-COOH and R-CO-R' respectively) and precursor ion (nitro groups, R-NO{sub 2}) scanning modes of a tandem mass spectrometer. Major organic aerosol sources are studied: vehicular emission and wood combustion for primary aerosol sources; and a secondary organic aerosol (SOA) produced through photooxidation of o-xylene. The results reveal significant differences in the functional group contents of these source aerosols. The laboratory generated SOA is dominated by carbonyls while carboxylics are preponderate in the wood combustion particles. On the other hand, vehicular emissions are characterised by a strong nitro content. The total amount of the three functional groups accounts for 1.7% (vehicular) to 13.5% (o-xylene photooxidation) of the organic carbon. Diagnostic functional group ratios are then used to tentatively discriminate sources of particles collected in an urban background environment located in an Alpine valley (Chamonix, France) during a strong winter pollution event. The three functional groups under study account for a total functionalization rate of 2.2 to 3.8% of the organic carbon in this ambient aerosol, which is also dominated by carboxylic moieties. In this particular case study of a deep alpine valley during winter, we show that the nitro- and carbonyl-to-carboxylic diagnostic ratios can be a useful tool to discriminate sources. In these conditions, the total OA concentrations are highly dominated by wood combustion OA. This result is confirmed by an organic markers source apportionment approach which assess a wood burning organic carbon contribution of about 60%. Finally, examples of functional

  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. 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...

  5. Estimation of Properties of Pure Organic Substances with Group and Pair Contributions

    OpenAIRE

    J.E.S. Ourique; SILVA TELLES A.

    1997-01-01

    ABSTRACTbstract - This work presents a new predictive method for the estimation of properties of pure organic substances. Each compound is assigned a molecular graph or an adjacency matrix representing its chemical structure, from which properties are then obtained as a summation of all contributions associated with functional groups and chemically bonded pairs of groups. The proposed technique is applied to the estimation of critical temperature, critical pressure, critical volume and norm...

  6. Technology Competence with Process Approach and its Relationship with Group Learning in Service Organizations

    OpenAIRE

    Rostam Nabizadeh; Mohsen Jokar; Ali Dashtizadeh

    2014-01-01

    The present study evaluated the effect of process-based technology competence and its dimensions on group learning and also investigated the relationship between two variables in good consistency process of service organizations with environment and society. After determining reliability and validity, for data collection, Lall (2001) technology competence and Neefe (2001) group learning questionnaires were applied. The study population was all the employees of water and Wastewater Company, re...

  7. 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.

  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. Project-based learning in organizations : towards a methodology for learning in groups

    NARCIS (Netherlands)

    Poell, R.F.; van der Krogt, F.J.

    2003-01-01

    This article introduces a methodology for employees in organizations to set up and carry out their own group learning projects. It is argued that employees can use project-based learning to make their everyday learning more systematic at times, without necessarily formalizing it. The article emphasi

  13. The Referential Function of Internal Communication Groups in Complex Organizations: An Empirical Analysis.

    Science.gov (United States)

    Taylor, James A.; Farace, Richard V.

    This paper argues that people who interact regularly and repetitively among themselves create a conjoint information space wherein common values, attitudes, and beliefs arise through the process of information transmission among the members in the space. Three major hypotheses concerning informal communication groups in organizations were tested…

  14. Soft Skills: An Important Asset Acquired from Organizing Regional Student Group Activities

    NARCIS (Netherlands)

    De Ridder, J.; Meysman, P.; Oluwagbemi, O.; Abeel, T.

    2014-01-01

    Contributing to a student organization, such as the International Society for Computational Biology Student Council (ISCB-SC) and its Regional Student Group (RSG) program, takes time and energy. Both are scarce commodities, especially when you are trying to find your place in the world of computatio

  15. An Epistemological Inquiry into Organic Chemistry Education: Exploration of Undergraduate Students' Conceptual Understanding of Functional Groups

    Science.gov (United States)

    Akkuzu, Nalan; Uyulgan, Melis Arzu

    2016-01-01

    This study sought to determine the levels of conceptual understanding of undergraduate students regarding organic compounds within different functional groups. A total of 60 students who were enrolled in the Department of Secondary Science and Mathematics Education of a Faculty of Education at a state university in Turkey and who had followed an…

  16. Smallholder group certification in Uganda – Analysis of internal control systems in two organic export companies

    Directory of Open Access Journals (Sweden)

    Moritz Reckling

    2010-04-01

    Full Text Available The organic agricultural sector of Uganda is among the most developed in Africa in terms of its professional institutional network and high growth rates of number of certified farmers and land area. Smallholder farmers are certified organic through contract production for export companies using a group certification scheme (internal control system - ICS. The ICS is a viable and well-accepted tool to certify small-scale producers in developing countries all over the world. Difficulties in certification are still stated to be among the main constraints for Uganda’s organic sector development. Therefore, this paper reports a qualitative case study comprising 34 expert interviews in two organic fresh-produce export companies in central Uganda, aiming to explore the challenges which underlie organic certification with ICS. The study shows that farmers cannot be labelled as ‘organic by default’ but deliberately engage in organic production as a marketing strategy. The small quantities purchased by the organic companies lead to a difficult marketing situation for the farmers, causing production and infiltration risks on the farm level. These risks require increased control that challenges the companies organizationally. The risks and control needs are a reason to involve farmers in ICS procedures and innovatively adapt the ICS by means of a bypass around formal perspective restrictions. The paper discusses different perspectives on risks, risk control and certification.

  17. The role of bridging organizations in environmental management: examining social networks in working groups

    Directory of Open Access Journals (Sweden)

    Adam A. Kowalski

    2015-06-01

    Full Text Available The linkage of diverse sets of actors and knowledge systems across management levels and institutional boundaries often poses one of the greatest challenges in adaptive management of natural resources. Bridging organizations can facilitate interactions among actors in management settings by lowering the transaction costs of collaboration. The Center for Ocean Solutions (COS is an example of a bridging organization that is focused on linking actors within the ocean sciences and governance arena through the use of working groups. This research examines how network connections between group members affect working group functionality and, more specifically, whether cohesive network structures allow groups to more effectively achieve their goals and objectives. A mixed-methods approach, incorporating both qualitative and quantitative data collection and analysis methods, is employed to understand the structural characteristics of COS working groups. The study finds that cohesive network structures are not associated with increased working group functionality. Strong, centralized leadership is a better predictor of working group success in achieving goals and objectives.

  18. Use of Protecting Groups in Carbohydrate Chemistry: An Advanced Organic Synthesis Experiment

    Science.gov (United States)

    Cunha, Anna C.; Pereira, Leticia O. R.; de Souza, Maria Cecília B. V.; Ferreira, Vitor F.

    1999-01-01

    A simple and inexpensive three-step reaction sequence for advanced experimental organic chemistry using D-glucosamine hydrochloride as starting material for the synthesis of 2-amino-2-deoxy-1,3,4,6-tetra-O-acetyl-b-D-glucopyranose hydrochloride is described. D-Glucosamine hydrochloride is a carbohydrate derivative isolated from crab shells. It is inexpensive and readily available from most chemical companies. This reaction sequence is appropriate for teaching undergraduate students the correct use of protecting groups. This is a major concept in organic synthesis and one of the determinant factors in the successful realization of multiple-step synthetic projects. The aim of the experiment is to protect the hydroxyl groups of D-glucosamine leaving its amino group as hydrochloride salt. The experiment deals only with protection and deprotection reactions. All products are crystalline substances. The amino group of d-glucosamine hydrochloride is protected by a condensation reaction with p-methoxybenzaldehyde to produce the Schiff's base as a mixture of a- and b-anomers. The second step involves the protection of all hydroxyl groups by esterification reaction using acetic anhydride, forming the imino-tetraacetate derivative as the b-anomer. The stereospecificity of this reaction at the anomeric center is due to the voluminous imino group at C-2. Removal of the amino protection group of this derivative is the final step, which can be accomplished by a selective acid hydrolysis affording the desired peracylated D-glucosamine hydrochloride.

  19. Effects of Aronia melanocarpa Constituents on Biofilm Formation of Escherichia coli and Bacillus cereus

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    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.

  20. 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)

  1. 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...

  2. 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...

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. 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...

  10. 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...

  11. Large nonlinear optical activity from hybrid inorganic–organic films with fluorinated benzene as isolation group

    International Nuclear Information System (INIS)

    Two azo chromophores containing fluorinated benzene and alkyl chain as isolation group were designed and synthesized, respectively, and the corresponding alkoxysilane dyes were obtained by coupling 3-isocyanatopropyltriethoxysilane with the chromophores. The molecular structures were verified by elemental analysis, hydrogen nuclear magnetic resonance, and Fourier transform infrared spectrum. Followed by a sol–gel process of the alkoxysilane dyes, inorganic–organic hybrid films were prepared by spin-coating. After electric poling, these hybrid films show the higher nonlinear optical (NLO) response than their analog containing chromophore DR1. Furthermore, the fluorinated benzene group exhibits better enhanced effect than the flexible alkyl group. The highest NLO coefficients (d33) of the hybrid film containing fluorinated benzene group was determined to be 140.5 pm V−1 at the chromophore concentration of 40%. - Highlights: • Inorganic-organic hybrid films are prepared via sol-gel process of alkoxysilane dyes • Nonlinear optical properties of hybrid films are investigated • Fluorinated benzene group effectively improves the nonlinear optical property

  12. Spread of consensus in self-organized groups of individuals: Hydrodynamics matters

    Science.gov (United States)

    De Rosis, A.; Lévêque, E.; Ubertini, S.; Succi, S.

    2016-01-01

    Nature routinely presents us with spectacular demonstrations of organization and orchestrated motion in living species. Efficient information transfer among the individuals is known to be instrumental to the emergence of spatial patterns (e.g. V-shaped formations for birds or diamond-like shapes for fishes), responding to a specific functional goal such as predatory avoidance or energy savings. Such functional patterns materialize whenever individuals appoint one of them as a leader with the task of guiding the group towards a prescribed target destination. It is here shown that, under specific conditions, the surrounding hydrodynamics plays a critical role in shaping up a successful group dynamics to reach the desired target.

  13. 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

  14. 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.

  15. 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.

  16. Validating a work group climate assessment tool for improving the performance of public health organizations

    Directory of Open Access Journals (Sweden)

    Tracy Allison

    2005-10-01

    Full Text Available Abstract Background This article describes the validation of an instrument to measure work group climate in public health organizations in developing countries. The instrument, the Work Group Climate Assessment Tool (WCA, was applied in Brazil, Mozambique, and Guinea to assess the intermediate outcomes of a program to develop leadership for performance improvement. Data were collected from 305 individuals in 42 work groups, who completed a self-administered questionnaire. Methods The WCA was initially validated using Cronbach's alpha reliability coefficient and exploratory factor analysis. This article presents the results of a second validation study to refine the initial analyses to account for nested data, to provide item-level psychometrics, and to establish construct validity. Analyses included eigenvalue decomposition analysis, confirmatory factor analysis, and validity and reliability analyses. Results This study confirmed the validity and reliability of the WCA across work groups with different demographic characteristics (gender, education, management level, and geographical location. The study showed that there is agreement between the theoretical construct of work climate and the items in the WCA tool across different populations. The WCA captures a single perception of climate rather than individual sub-scales of clarity, support, and challenge. Conclusion The WCA is useful for comparing the climates of different work groups, tracking the changes in climate in a single work group over time, or examining differences among individuals' perceptions of their work group climate. Application of the WCA before and after a leadership development process can help work groups hold a discussion about current climate and select a target for improvement. The WCA provides work groups with a tool to take ownership of their own group climate through a process that is simple and objective and that protects individual confidentiality.

  17. 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.

  18. 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.

  19. 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

  20. 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

  1. Accountable Care Organizations and Clinical Commissioning Groups face an uncertain challenge for improving public health

    Directory of Open Access Journals (Sweden)

    Douglas J. Noble

    2012-04-01

    Full Text Available Accountable Care Organizations (ACO in the United States of America (USA and Clinical Commissioning Groups (CCG in the United Kingdom (UK are new proposed organizations in health services both tasked with a role which includes improving public health.  Although there are very significant differences between the UK and USA health systems there appears to be a similar confusion as to how ACO and CCG will regard and address public or population health.  The role of ACO in improving population health and evaluating the health needs of their registered and insured patients remains ill-defined and poorly explored.  Likewise, in the current UK National Health Service (NHS reorganisation, control and commissioning of appropriate local health services are passing from Primary Care Trusts (PCT to new cross-organizational structures (CCG.  CCG groups aim to be, like ACO, physician led.  They will also assume a role for public or population health, but this role, like that of the newly-forming ACO, is currently unclear.  Lessons learned from the USA and UK experience of new organizations tasked with a role in improving public health may inform mechanisms for physician led organizations in the UK and the USA to assess health needs, monitor population health information and improve population health outcomes.

  2. 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.

  3. Technical Note: Development of chemoinformatic tools to enumerate functional groups in molecules for organic aerosol characterization

    Science.gov (United States)

    Ruggeri, Giulia; Takahama, Satoshi

    2016-04-01

    Functional groups (FGs) can be used as a reduced representation of organic aerosol composition in both ambient and controlled chamber studies, as they retain a certain chemical specificity. Furthermore, FG composition has been informative for source apportionment, and various models based on a group contribution framework have been developed to calculate physicochemical properties of organic compounds. In this work, we provide a set of validated chemoinformatic patterns that correspond to (1) a complete set of functional groups that can entirely describe the molecules comprised in the α-pinene and 1,3,5-trimethylbenzene MCMv3.2 oxidation schemes, (2) FGs that are measurable by Fourier transform infrared spectroscopy (FTIR), (3) groups incorporated in the SIMPOL.1 vapor pressure estimation model, and (4) bonds necessary for the calculation of carbon oxidation state. We also provide example applications for this set of patterns. We compare available aerosol composition reported by chemical speciation measurements and FTIR for different emission sources, and calculate the FG contribution to the O : C ratio of simulated gas-phase composition generated from α-pinene photooxidation (using the MCMv3.2 oxidation scheme).

  4. Technical Note: Development of chemoinformatic tools to enumerate functional groups in molecules for organic aerosol characterization

    Directory of Open Access Journals (Sweden)

    G. Ruggeri

    2015-11-01

    Full Text Available Functional groups (FGs can be used as a reduced representation of organic aerosol composition in both ambient and environmental controlled chamber studies, as they retain a certain chemical specificity. Furthermore, FG composition has been informative for source apportionment, and various models based on a group contribution framework have been developed to calculate physicochemical properties of organic compounds. In this work, we provide a set of validated chemoinformatic patterns that correspond to: (1 groups incorporated in the SIMPOL.1 vapor pressure estimation model, (2 FGs that are measurable by Fourier transform infrared spectroscopy (FTIR, (3 a complete set of functional groups that can entirely describe the molecules comprised in the α-pinene and 1,3,5-trimethylbenzene MCMv3.2 oxidation schemes, and (4 bonds necessary for the calculation of carbon oxidation state. We also provide example applications for this set of patterns. We compare available aerosol composition reported by chemical speciation measurements and FTIR for different emission sources, and calculate the FG contribution to the O : C ratio of simulated gas phase composition generated from α-pinene photooxidation (using MCMv3.2 oxidation scheme.

  5. Symmetry breaking in the opinion dynamics of a multi-group project organization

    International Nuclear Information System (INIS)

    A bounded confidence model of opinion dynamics in multi-group projects is presented in which each group's opinion evolution is driven by two types of forces: (i) the group's cohesive force which tends to restore the opinion back towards the initial status because of its company culture; and (ii) nonlinear coupling forces with other groups which attempt to bring opinions closer due to collaboration willingness. Bifurcation analysis for the case of a two-group project shows a cusp catastrophe phenomenon and three distinctive evolutionary regimes, i.e., a deadlock regime, a convergence regime, and a bifurcation regime in opinion dynamics. The critical value of initial discord between the two groups is derived to discriminate which regime the opinion evolution belongs to. In the case of a three-group project with a symmetric social network, both bifurcation analysis and simulation results demonstrate that if each pair has a high initial discord, instead of symmetrically converging to consensus with the increase of coupling scale as expected by Gabbay's result (Physica A 378 (2007) p. 125 Fig. 5), project organization (PO) may be split into two distinct clusters because of the symmetry breaking phenomenon caused by pitchfork bifurcations, which urges that apart from divergence in participants' interests, nonlinear interaction can also make conflict inevitable in the PO. The effects of two asymmetric level parameters are tested in order to explore the ways of inducing dominant opinion in the whole PO. It is found that the strong influence imposed by a leader group with firm faith on the flexible and open minded follower groups can promote the formation of a positive dominant opinion in the PO

  6. Symmetry breaking in the opinion dynamics of a multi-group project organization

    Science.gov (United States)

    Zhu, Zhen-Tao; Zhou, Jing; Li, Ping; Chen, Xing-Guang

    2012-10-01

    A bounded confidence model of opinion dynamics in multi-group projects is presented in which each group's opinion evolution is driven by two types of forces: (i) the group's cohesive force which tends to restore the opinion back towards the initial status because of its company culture; and (ii) nonlinear coupling forces with other groups which attempt to bring opinions closer due to collaboration willingness. Bifurcation analysis for the case of a two-group project shows a cusp catastrophe phenomenon and three distinctive evolutionary regimes, i.e., a deadlock regime, a convergence regime, and a bifurcation regime in opinion dynamics. The critical value of initial discord between the two groups is derived to discriminate which regime the opinion evolution belongs to. In the case of a three-group project with a symmetric social network, both bifurcation analysis and simulation results demonstrate that if each pair has a high initial discord, instead of symmetrically converging to consensus with the increase of coupling scale as expected by Gabbay's result (Physica A 378 (2007) p. 125 Fig. 5), project organization (PO) may be split into two distinct clusters because of the symmetry breaking phenomenon caused by pitchfork bifurcations, which urges that apart from divergence in participants' interests, nonlinear interaction can also make conflict inevitable in the PO. The effects of two asymmetric level parameters are tested in order to explore the ways of inducing dominant opinion in the whole PO. It is found that the strong influence imposed by a leader group with firm faith on the flexible and open minded follower groups can promote the formation of a positive dominant opinion in the PO.

  7. Symmetry breaking in the opinion dynamics of a multi-group project organization

    Institute of Scientific and Technical Information of China (English)

    Zhu Zhen-Tao; Zhou Jing; Li Ping; Chen Xing-Guang

    2012-01-01

    A bounded confidence model of opinion dynamics in multi-group projects is presented in which each group's opinion evolution is driven by two types of forces:(i) the group's cohesive force which tends to restore the opinion back towards the initial status because of its company culture; and (ii) nonlinear coupling forces with other groups which attempt to bring opinions closer due to collaboration willingness.Bifurcation analysis for the case of a two-group project shows a cusp catastrophe phenomenon and three distinctive evolutionary regimes,i.e.,a deadlock regime,a convergence regime,and a bifurcation regime in opinion dynamics.The critical value of initial discord between the two groups is derived to discriminate which regime the opinion evolution belongs to.In the case of a three-group project with a symmetric social network,both bifurcation analysis and simulation results demonstrate that if each pair has a high initial discord,instead of symmetrically converging to consensus with the increase of coupling scale as expected by Gabbay's result (Physica A 378 (2007) p.125 Fig.5),project organization (PO) may be split into two distinct clusters because of the symmetry breaking phenomenon caused by pitchfork bifurcations,which urges that apart from divergence in participants' interests,nonlinear interaction can also make conflict inevitable in the PO.The effects of two asymmetric level parameters are tested in order to explore the ways of inducing dominant opinion in the whole PO.It is found that the strong influence imposed by a leader group with firm faith on the flexible and open minded follower groups can promote the formation of a positive dominant opinion in the PO.

  8. Risk groups in children under six months of age using self-organizing maps.

    Science.gov (United States)

    Schilithz, A O C; Kale, P L; Gama, S G N; Nobre, F F

    2014-06-01

    Fetal and infant growth tends to follow irregular patterns and, particularly in developing countries, these patterns are greatly influenced by unfavorable living conditions and interactions with complications during pregnancy. The aim of this study was to identify groups of children with different risk profiles for growth development. The study sample comprised 496 girls and 508 boys under six months of age from 27 pediatric primary health care units in the city of Rio de Janeiro, Brazil. Data were obtained through interviews with the mothers and by reviewing each child's health card. An unsupervised learning, know as a self-organizing map (SOM) and a K-means algorithm were used for cluster analysis to identify groups of children. Four groups of infants were identified. The first (139) consisted of infants born exclusively by cesarean delivery, and their mothers were exclusively multiparous; the highest prevalences of prematurity and low birthweight, a high prevalence of exclusive breastfeeding and a low proportion of hospitalization were observed for this group. The second (247 infants) and the third (298 infants) groups had the best and worst perinatal and infant health indicators, respectively. The infants of the fourth group (318) were born heavier, had a low prevalence of exclusive breastfeeding, and had a higher rate of hospitalization. Using a SOM, it was possible to identify children with common features, although no differences between groups were found with respect to the adequacy of postnatal weight. Pregnant women and children with characteristics similar to those of group 3 require early intervention and more attention in public policy. PMID:24725333

  9. The role of beaded activated carbon's surface oxygen groups on irreversible adsorption of organic vapors.

    Science.gov (United States)

    Jahandar Lashaki, Masoud; Atkinson, John D; Hashisho, Zaher; Phillips, John H; Anderson, James E; Nichols, Mark

    2016-11-01

    The objective of this study is to determine the contribution of surface oxygen groups to irreversible adsorption (aka heel formation) during cyclic adsorption/regeneration of organic vapors commonly found in industrial systems, including vehicle-painting operations. For this purpose, three chemically modified activated carbon samples, including two oxygen-deficient (hydrogen-treated and heat-treated) and one oxygen-rich sample (nitric acid-treated) were prepared. The samples were tested for 5 adsorption/regeneration cycles using a mixture of nine organic compounds. For the different samples, mass balance cumulative heel was 14 and 20% higher for oxygen functionalized and hydrogen-treated samples, respectively, relative to heat-treated sample. Thermal analysis results showed heel formation due to physisorption for the oxygen-deficient samples, and weakened physisorption combined with chemisorption for the oxygen-rich sample. Chemisorption was attributed to consumption of surface oxygen groups by adsorbed species, resulting in formation of high boiling point oxidation byproducts or bonding between the adsorbates and the surface groups. Pore size distributions indicated that different pore sizes contributed to heel formation - narrow micropores (<7Å) in the oxygen-deficient samples and midsize micropores (7-12Å) in the oxygen-rich sample. The results from this study help explain the heel formation mechanism and how it relates to chemically tailored adsorbent materials. PMID:27295065

  10. Relations between soil structure, number of selected groups of soil microorganisms, organic matter content and cultivation

    Directory of Open Access Journals (Sweden)

    J. Stawiński

    1996-03-01

    Full Text Available The aim of this work was to fiut relations between the number of selected groups of soil microorganisms, water stability of soil aggregates, soil porosity and the organic matter content on the basis of field experiment. Two types of soil were used simultaneously for the research: chernozemic rendzina and brown soil. Rotation system was used in plant cultivation. Chemical, physical and microbiological analyses were carried out on the control object and on objects with organic fertilizers and mineral fertilizers N, P, K. Differences in the sum of fractions of organic C, chiefly in the easily oxidizing fractions in experimental fields on rendzina, in comparison to those on brown soil, can be the result of the predominance of zymogenous bacteria over autochtonous bacteria in the rendzina. Easily oxidizable fractions of C contained in the organic substance of particular fields can be utilized by a high ratio of zymogenous bacteria in the soil samples. It should be noted that characteristic differences in the number of bacteria have been observed in the two types of soils examined. The number of autochtonous microorganisms in brown soil was twice as much as in rendzina. Zymogenous microorganisms constitute more than 90 % of the total number of microorganisms in rendzina. Under the cultivation of red clover an increase of water stability of soil aggregates was stated. From the porosimetric analyses no changes under different cultivation of two soils were observed. The ratio of microorganisms was connected with the type of soil and the system of cultivation.

  11. Soft skills: an important asset acquired from organizing regional student group activities.

    Science.gov (United States)

    de Ridder, Jeroen; Meysman, Pieter; Oluwagbemi, Olugbenga; Abeel, Thomas

    2014-07-01

    Contributing to a student organization, such as the International Society for Computational Biology Student Council (ISCB-SC) and its Regional Student Group (RSG) program, takes time and energy. Both are scarce commodities, especially when you are trying to find your place in the world of computational biology as a graduate student. It comes as no surprise that organizing ISCB-SC-related activities sometimes interferes with day-to-day research and shakes up your priority list. However, we unanimously agree that the rewards, both in the short as well as the long term, make the time spent on these extracurricular activities more than worth it. In this article, we will explain what makes this so worthwhile: soft skills. PMID:24992198

  12. From Grouping to Coupling: A New Perceptual Organization in Vision, Psychology, and Biology

    Science.gov (United States)

    Pinna, Baingio; Porcheddu, Daniele; Deiana, Katia

    2016-01-01

    In this work, perceptual organization has been studied with the same spirit and phenomenological methods used by Gestalt psychologists. This was accomplished through new conditions that cannot be explained in terms of the classical principles of grouping. Perceptual grouping represents the way through which our visual system builds integrated elements on the basis of the maximal homogeneity among the components of the stimulus pattern. Our results demonstrated the inconsistency of organization by grouping, and more importantly, the inconsistency of the principle of similarity. On the contrary, they suggested the unique role played by the principle of dissimilarity among elements that behaves like an accent or a visual emphasis within a whole. The principle of accentuation was here considered as imparting a directional structure to the elements and to the whole object thus creating new phenomena. The salience of the resulting phenomena reveals the supremacy of dissimilarity in relation to similarity and the fact that it belongs to a further organization dynamics that we called “coupling.” In biology, coupling and its principle of accentuation are very strongly related to disruptive camouflage. Moreover, they are source of sexual attraction. They advertise the presence and elicit species identification/communication. In human beings accentuation is needed to show ourselves to others, to understand the way we dress, choose, and create clothes or invent fashion, the way we change our body accentuating several parts and hiding some others, the way we use maquillage. The existence of maquillage itself is derived from the need to accentuate something with the purpose to increase sexual attraction, to exhibit physical strength and beauty, to show or hide social status (e.g., being the king, a warrior, a priest, etc.). Last but not least, accentuation plays a basic role also in making it easier or difficult to read and understand written words. PMID:27471483

  13. Bonding of ppb levels of methyl mercury to reduced sulfur groups in soil organic matter.

    Science.gov (United States)

    Karlsson, Torbjörn; Skyllberg, Ulf

    2003-11-01

    The strong binding of CH3Hg+ to natural organic matter (NOM) in soils and waters determines the speciation of CH3Hg under aerobic conditions and indirectly its bioavailability and rates of demethylation. In lab experiments, halides (Cl, Br, I) were used as competing ligands to determine the strength of CH3Hg+ binding to solid-phase soil organic carbon (SOC) and to dissolved soil organic carbon (DOC) as a function of time, pH, and concentration of halide. Experiments were conducted with native concentrations of CH3Hg (1.7-9.8 ng g(-1)) in organic soils, and equilibrium concentrations of CH3Hg were determined by species-specific-isotope-dilution (SSID) gas-chromatography-induced-coupled-plasma-mass-spectrometry (GC-ICP-MS). A simple model (RS- + CH3Hg+ = CH3HgSR; log KCH3HgSR) was used to simulate the binding to SOC and DOC, in which the binding sites (RSH) were independently determined by X-ray absorption near-edge structure (XANES) spectroscopy. The pKa values of RSH groups were fixed at 8.50 and 9.95, reflecting the two major thiol groups in proteins. Log KCH3HgSR values determined for SOC and DOC were similar, showing a range of 15.6-17.1 for all experiments covering a pH range of 2.0-5.1. Despite large differences in affinities between Cl, Br, and I for CH3Hg+, determined constants were independent of type and concentration of halide used in the experiments (log KCH3HgSR = 16.1-16.7 at pH 3.5-3.6). Even if our log KCH3HgSR values were conditional in that they decreased with pH above 3.5, they were in fair agreement with stability constants determined for the association between CH3Hg+ and thiol groups in well-defined organic molecules (log K1 = 15.7-17.5). Speciation calculations based on our results show that, in absence of substantial concentrations of inorganic sulfides, neutral chloro-complexes (CH3HgCl) and free CH3Hg+ reach concentrations on the order of 10(-17)-10(-18) M at pH 5 in soil solutions with 3 x 10(-5) M of chloride. PMID:14620818

  14. Introduction of bridging and pendant organic groups into mesoporous alumina materials.

    Science.gov (United States)

    Grant, Stacy M; Woods, Stephan M; Gericke, Arne; Jaroniec, Mietek

    2011-11-01

    Incorporation of organic functionalities into soft-templated mesoporous alumina was performed via organosilane-assisted evaporation induced self-assembly using aluminum alkoxide precursors and block copolymer templates. This strategy permits one to obtain mesoporous alumina-based materials with tailorable adsorption, surface and structural properties. Isocyanurate, ethane, mercaptopropyl, and ureidopropyl-functionalized mesoporous alumina materials were synthesized with relatively high surface area and large pore volume with uniform and wormhole-like mesopores. The presence of organosilyl groups within these hybrid materials was confirmed by IR or Raman spectroscopy and their concentration was determined by elemental analysis. PMID:21988174

  15. Phosphor Dysprosium-Doped Layered Double Hydroxides Exchanged with Different Organic Functional Groups

    OpenAIRE

    David Ricardo Martínez Vargas; Oviedo, Mariana J.; Fabio da Silva Lisboa; Fernando Wypych; Hirata, Gustavo A.; Gregorio Guadalupe Carbajal Arizaga

    2013-01-01

    The layers of a Zn/Al layered double hydroxide (LDH) were doped with Dy3+ cations. Among some compositions, the Zn2+ : Al3+ : Dy3+ molar ratio equal to 30 : 9 : 1 presented a single crystalline phase. Organic anions with carboxylic, amino, sulfate, or phosphate functional groups were intercalated as single layers between LDH layers as confirmed by X-ray diffraction and infrared spectroscopy. Photoluminescence spectra of the nitrate intercalated LDH showed a wide emission band with strong inte...

  16. Comparison of Healthcare Quality Outcomes Between Accountable Care Organizations and Physician Group Practices.

    Science.gov (United States)

    Singh, Sukhchain; Khosla, Sandeep; Sethi, Ankur

    2015-01-01

    Accountable Care Organizations (ACOs) were created under the Affordable Care Act to deliver better quality of care at reduced cost compare with the traditional fee-for-service model. But their effectiveness in achieving healthcare quality metrics is unclear. We analyzed ACO and physician group practice (PGP) performance rates for the single coronary artery disease measure and four diabetes mellitus measures now publicly reported on the Medicare Physician Compare Web site for program year 2012. There was no statistically significant difference in reported quality measures between ACOs and PGPs. Our study shows that PGPs can achieve outcomes at par with ACOs. PMID:26223106

  17. 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

  18. Danish stable schools for experiential common learning in groups of organic dairy farmers

    DEFF Research Database (Denmark)

    Waarst, M.; Nissen, T.B; Østergaard, I.;

    2007-01-01

    The farmer field school (FFS) is a concept for farmers' learning, knowledge exchange, and empowerment that has been developed and used in developing countries. In Denmark, a research project focusing on explicit non-antibiotic strategies involves farmers who have actively expressed an interest in...... phasing out antibiotics from their herds through promotion of animal health. One way of reaching this goal was to form participatory focused farmer groups in an FFS approach, which was adapted to Danish conditions and named "stable schools." Four stable schools were established and went through a 1-yr...... context, problems were identified and solutions proposed based on each farmer's individual goals. In this article, we describe the experiences of 4 stable school groups (each comprising farmers and a facilitator), and the common process of building a concept that is suitable for Danish organic dairy...

  19. Prediction of heat capacities and heats of vaporization of organic liquids by group contribution methods

    DEFF Research Database (Denmark)

    Ceriani, Roberta; Gani, Rafiqul; Meirelles, A.J.A.

    2009-01-01

    In the present work a group contribution method is proposed for the estimation of the heat capacity of organic liquids as a function of temperature for fatty compounds found in edible oil and biofuels industries. The data bank used for regression of the group contribution parameters (1395 values......-2085] and the Rowlinson-Bondi equation. Also, the predictive performance of general correlations of heats of vaporization based on the corresponding-states method, such as Carruth and Kobayashi [G.F. Carruth, R. Kobayashi, Ind. Eng. Chem. Fundam. 11 (1972) 509-516], Sivaraman et al. [A. Sivaraman, J.W. Magee, R...... in the prediction of heats of vaporization of fatty compounds based on the vapor pressure model of Ceriani and Meirelles [R. Ceriani. A.J.A. Meirelles, Fluid Phase Equilib. 215 (2004) 227-236] and its combination with the Clausius-Clapeyron equation has been Studied. (C) 2009 Elsevier B.V. All rights reserved....

  20. 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

  1. Organic petrography:An approach for identification of maceral groups in Gheshlagh coal area, Eastern Alborz

    Directory of Open Access Journals (Sweden)

    Tahereh Rabani

    2016-07-01

    Full Text Available Introduction Maceral is a term to introduce organic components visible under a microscope (Stopes, 1935. The physical and chemical characteristics of macerals such as elemental composition, moisture content, hardness, density and petrographic characteristics differ. The differences in the physical and chemical characteristics of macerals are reflected in their industrial behavior.(Parkash, 1985. Petrographic analysis provides information on the various physical components of coals (Suwarna and Hemanto, 2007 and determination of quality of coal, coalification rate, composition and characteristics of coke and paleoenvironmental deposition (Taylor et al., 1998. Sampling and methodology Coal samples were collected from freshly mined coal from 11 coal seams of 4 active coal mines (Cheshlagh, Zemestan Yourt, Narges Chal and Cheshmehsaran for organic petrography in the Gheshlagh coal deposits. All samples were collected and stored in plastic bags to prevent contamination and weathering. Samples were prepared for microscopic analysis by reflected light following ASTM Standard procedure D2797-04. For microscopic study, coal samples were crushed to1-mm size fraction (18 mesh size, mounted in epoxy resin and polished. Three polished samples were prepared for each coal seam. The petrographic composition was obtained by maceral analyses under standard conditions (ISO 7404/3, 2009, for maceral analysis. Maceral point counting (based on 400 points analyses were performed using an Olympus BX51 reflected light microscope. The terminology used to identify and describe the organic matter particles is the one proposed by the International Committee for Coal and Organic Petrology (ICCP, 1998; ICCP, 2001; Scott and Glasspool, 2007; Taylor et al., 1998; Stach et al., 1982; Hower et al., 2009; Hower and Wagner, 2012. Organic petrography of theGheshlagh coal seams The vitrinite maceral group is dominant in all coal seams (66.2 to 87.2 vol.% and includes collodetrinite

  2. Statement of the Declaration of Istanbul Custodian Group Regarding Payments to Families of Deceased Organ Donors.

    Science.gov (United States)

    Capron, Alexander Morgan; Delmonico, Francis L; Dominguez-Gil, Beatriz; Martin, Dominique Elizabeth; Danovitch, Gabriel M; Chapman, Jeremy

    2016-09-01

    Governmental and private programs that pay next of kin who give permission for the removal of their deceased relative's organs for transplantation exist in a number of countries. Such payments, which may be given to the relatives or paid directly for funeral expenses or hospital bills unrelated to being a donor, aim to increase the rate of donation. The Declaration of Istanbul Custodian Group-in alignment with the World Health Organization Guiding Principles and the Council of Europe Convention Against Trafficking in Human Organs-has adopted a new policy statement opposing such practices. Payment programs are unwise because they produce a lower rate of donations than in countries with voluntary, unpaid programs; associate deceased donation with being poor and marginal in society; undermine public trust in the determination of death; and raise doubts about fair allocation of organs. Most important, allowing families to receive money for donation from a deceased person, who is at no risk of harm, will make it impossible to sustain prohibitions on paying living donors, who are at risk. Payment programs are also unethical. Tying coverage for funeral expenses or healthcare costs to a family allowing organs to be procured is exploitative, not "charitable." Using payment to overcome reluctance to donate based on cultural or religious beliefs especially offends principles of liberty and dignity. Finally, while it is appropriate to make donation "financially neutral"-by reimbursing the added medical costs of evaluating and maintaining a patient as a potential donor-such reimbursement may never be conditioned on a family agreeing to donate. PMID:27355820

  3. 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".

  4. 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...

  5. 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

  6. Cooperative Networks: Altruism, Group Solidarity, Reciprocity, and Sanctioning in Ugandan Producer Organizations.

    Science.gov (United States)

    Baldassarri, Delia

    2015-09-01

    Repeated interaction and social networks are commonly considered viable solutions to collective action problems. This article identifies and systematically measures four general mechanisms--that is, generalized altruism, group solidarity, reciprocity, and the threat of sanctioning--and tests which of them brings about cooperation in the context of Ugandan producer organizations. Using an innovative methodological framework that combines "lab-in-the-field" experiments with survey interviews and complete social networks data, the article goes beyond the assessment of a relationship between social networks and collective outcomes to study the mechanisms that favor cooperative behavior. The article first establishes a positive relationship between position in the network structure and propensity to cooperate in the producer organization and then uses farmers' behavior in dictator and public goods games to test different mechanisms that may account for such a relationship. Results show that cooperation is induced by patterns of reciprocity that emerge through repeated interaction rather than other-regarding preferences like altruism or group solidarity. PMID:26594712

  7. Insight into the contribution of individual functional groups to the flash point of organic compounds

    International Nuclear Information System (INIS)

    Highlights: • A remarkably simple approach to flash point prediction is put forward. • It combines a power law expression with geometrical fragments. • It proves as reliable as models based on advanced QSPR techniques. • In addition, it provides insight into the contributions of functional groups. • Training and test sets include respectively 287 and 1170 compounds. - Abstract: Flash point temperatures of organic compounds are predicted on the basis of a power law involving 21 additive contributions associated with non-hydrogen atoms and ring structures. The model is parametrized against a previous data set of 287 simple organic molecules. An average absolute error of 8.6 K and a maximal error of about 50 K are obtained when applying this model to an external test set of 488 compounds within its applicability domain. The overall performances of the method are remarkable given its simplicity and the small number of parameters involved. In addition, the present work provides valuable insight into the influence of individual functional groups to flash point temperatures

  8. Versatile Oxidation Methods for Organic and Inorganic Substrates Catalyzed by Platinum-Group Metals on Carbons.

    Science.gov (United States)

    Sawama, Yoshinari; Asai, Shota; Monguchi, Yasunari; Sajiki, Hironao

    2016-02-01

    Platinum-group metals on activated carbon catalysts, represented by Pd/C, Ru/C, Rh/C, etc., are widely utilized to accomplish green and sustainable organic reactions due to their favorable features, such as easy handling, recoverability, and reusability. The efficient oxidation methods of various organic compounds using heterogeneous platinum-group metals on carbons with or without added oxidants are summarized in this Personal Account. The oxidation of internal alkynes into diketones was effectively catalyzed by Pd/C in the presence of dimethyl sulfoxide and molecular oxygen or pyridine N-oxide. The Pd/C-catalyzed mild combustion of gaseous hydrogen with molecular oxygen provided hydrogen peroxide, which could be directly utilized for the oxidation of sulfide derivatives into sulfoxides. Furthermore, the Ru/C-catalyzed aerobic oxidation of primary and secondary alcohols gave the corresponding aldehydes and ketones, respectively. On the other hand, the dehydrogenative oxidation of secondary alcohols into ketones was achieved using Rh/C in water, and primary alcohols were effectively dehydrogenated by Pd/C in water under mildly reduced pressure to produce carboxylic acids. PMID:26666634

  9. 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)

  10. 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.

  11. 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

  12. 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.

  13. 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

  14. 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

  15. 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.

  16. 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

  17. 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.

  18. 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

  19. 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

  20. 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...

  1. 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.

  2. 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.

  3. 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...

  4. 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...

  5. 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.

  6. 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...

  7. 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...

  8. 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...

  9. 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.

  10. Clinical trials update of the European Organization for Research and Treatment of Cancer Breast Cancer Group

    International Nuclear Information System (INIS)

    The present clinical trial update consists of a review of two of eight current studies (the 10981-22023 AMAROS trial and the 10994 p53 trial) of the European Organization for Research and Treatment of Cancer Breast Cancer Group, as well as a preview of the MIND-ACT trial. The AMAROS trial is designed to prove equivalent local/regional control for patients with proven axillary lymph node metastasis by sentinel node biopsy if treated with axillary radiotherapy instead of axillary lymph node dissection, with reduced morbidity. The p53 trial started to assess the potential predictive value of p53 using a functional assay in yeast in patients with locally advanced/inflammatory or large operable breast cancer prospectively randomised to a taxane regimen versus a nontaxane regimen

  11. 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

  12. 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.

  13. 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

  14. The occurrence and distribution of a group of organic micropollutants in Mexico City's water sources.

    Science.gov (United States)

    Félix-Cañedo, Thania E; Durán-Álvarez, Juan C; Jiménez-Cisneros, Blanca

    2013-06-01

    The occurrence and distribution of a group of 17 organic micropollutants in surface and groundwater sources from Mexico City was determined. Water samples were taken from 7 wells, 4 dams and 15 tanks where surface and groundwater are mixed and stored before distribution. Results evidenced the occurrence of seven of the target compounds in groundwater: salicylic acid, diclofenac, di-2-ethylhexylphthalate (DEHP), butylbenzylphthalate (BBP), triclosan, bisphenol A (BPA) and 4-nonylphenol (4-NP). In surface water, 11 target pollutants were detected: same found in groundwater as well as naproxen, ibuprofen, ketoprofen and gemfibrozil. In groundwater, concentration ranges of salicylic acid, 4-NP and DEHP, the most frequently found compounds, were 1-464, 1-47 and 19-232 ng/L, respectively; while in surface water, these ranges were 29-309, 89-655 and 75-2,282 ng/L, respectively. Eleven target compounds were detected in mixed water. Concentrations in mixed water were higher than those determined in groundwater but lower than the detected in surface water. Different to that found in ground and surface water, the pesticide 2,4-D was found in mixed water, indicating that some pollutants can reach areas where they are not originally present in the local water sources. Concentration of the organic micropollutants found in this study showed similar to lower to those reported in water sources from developed countries. This study provides information that enriches the state of the art on the occurrence of organic micropollutants in water sources worldwide, notably in megacities of developing countries. PMID:23542484

  15. 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...

  16. 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...

  17. Fluid forces enhance the performance of an aspirant leader in self-organized living groups.

    Directory of Open Access Journals (Sweden)

    Alessandro De Rosis

    Full Text Available In this paper, the performance of an individual aiming at guiding a self-organized group is numerically investigated. A collective behavioural model is adopted, accounting for the mutual repulsion, attraction and orientation experienced by the individuals. Moreover, these represent a set of solid particles which are supposed to be immersed in a fictitious viscous fluid. In particular, the lattice Boltzmann and Immersed boundary methods are used to predict the fluid dynamics, whereas the effect of the hydrodynamic forces on particles is accounted for by solving the equation of the solid motion through the time discontinuous Galerkin scheme. Numerical simulations are carried out by involving the individuals in a dichotomous process. On the one hand, an aspirant leader (AL additional individual is added to the system. AL is forced to move along a prescribed direction which intersects the group. On the other hand, these tend to depart from an obstacle represented by a rotating lamina which is placed in the fluid domain. A numerical campaign is carried out by varying the fluid viscosity and, as a consequence, the hydrodynamic field. Moreover, scenarios characterized by different values of the size of the group are investigated. In order to estimate the AL's performance, a proper parameter is introduced, depending on the number of individuals following AL. Present findings show that the sole collective behavioural equations are insufficient to predict the AL's performance, since the motion is drastically affected by the presence of the surrounding fluid. With respect to the existing literature, the proposed numerical model is enriched by accounting for the presence of the encompassing fluid, thus computing the hydrodynamic forces arising when the individuals move.

  18. The abundance and organization of polypeptides associated with antigens of the Rh blood group system.

    Science.gov (United States)

    Gardner, B; Anstee, D J; Mawby, W J; Tanner, M J; von dem Borne, A E

    1991-06-01

    Twelve murine monoclonal antibodies, which react with human red cells of common Rh phenotype but give weak or negative reactions with Rh null erythrocytes, were used in quantitative binding assays and competitive binding assays to investigate the abundance and organization of polypeptides involved in the expression of antigens of the Rh blood group system. Antibodies of the R6A-type (R6A, BRIC-69, BRIC-207) and the 2D10-type (MB-2D10, LA18.18, LA23.40) recognize related structures and 100,000-200,000 molecules of each antibody bind maximally to erythrocytes of common Rh phenotype. Antibodies of the BRIC-125 type (BRICs 32, 122, 125, 126, 168, 211) recognize structures that are unrelated to those recognized by R6A-type and 2D10-type antibodies and between 10,000 and 50,000 antibody molecules bind maximally to erythrocytes of the common Rh phenotype. The binding of antibodies of the R6A-type and the 2D10-type, but not of antibodies of the BRIC-125-type could be partially inhibited by human anti-D antibodies (polyclonal and monoclonal) and a murine anti-e-like antibody. These results are consistent with evidence (Moore & Green 1987; Avent et al., 1988b) that the Rh blood group antigens are associated with a complex that comprises two groups of related polypeptides of M(r) 30,000 and M(r) 35,000-100,000, respectively, and suggest that there are 1-2 x 10(5) copies of this complex per erythrocyte. The polypeptide recognized by antibodies of the BRIC-125 type is likely to be associated with this complex. PMID:9259831

  19. 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.

  20. Observing Engineering Student Teams from the Organization Behavior Perspective Using Linguistic Analysis of Student Reflections and Focus Group Interviews

    Science.gov (United States)

    Kearney, Kerri S.; Damron, Rebecca; Sohoni, Sohum

    2015-01-01

    This paper investigates group/team development in computer engineering courses at a University in the Central USA from the perspective of organization behavior theory, specifically Tuckman's model of the stages of group development. The investigation, conducted through linguistic analysis of student reflection essays, and through focus group…

  1. Welfare of entire males and females in organic pig production when reared in single-sex groups

    DEFF Research Database (Denmark)

    Thomsen, Rikke; Bonde, Marianne Kjær; Rousing, Tine;

    2012-01-01

    In the 25 EU countries more than 100 million male piglets are castrated each year. Castration is particularly problematic in organic pig production because it conflicts with the high welfare and other ethical standards associated with this system of animal production. The objective was to...... investigate possible welfare implications of producing organic entire male pigs. A total of 281 entire male pigs and 250 female pigs, raised in accordance with Danish organic standards in two commercial herds, were distributed into 15 male groups and 15 female groups. The pigs were observed at 40, 70 and 90...

  2. Institutionalizing environmental due diligence as part of the organization's culture: The Suncor Oil Sands Group experience

    International Nuclear Information System (INIS)

    The Suncor Oil Sands Group produces ca 22 million bbl/y of synthetic crude oil from oil sands in northern Alberta. Initiatives taken by the Group to install environmental due diligence as an integral part of Suncor culture are reviewed. Environmental due diligence means taking all reasonable care to safeguard the environment. To practice environmental due diligence, the organization and its members must have an environmental consciousness that can be observed, measured, and monitored through daily practices. In the period from startup of the oil sands plant in 1967 to the mid-1970s, Suncor culture could be described as research oriented, oriented toward examination of the viability of extracting oil from the oil sands and the development of new extraction processes. Management then moved toward a more production-based culture, in which environmental issues were sometimes perceived to be in conflict with production goals. External factors toward the end of the 1980s created a culture shift to an integration of production culture with social entities including environmental consciousness. A corporate push toward a new environmental culture was first concretized when the management's Health and Safety Policy was changed in 1990 to the Health, Safety and Environment Policy. A new Environmental Diligence Program was implemented in three phases, including planning, development of a comprehensive environmental management system, and implementation. Installation of the Program in the first phase is described, focusing on employee and management training, and results of the installation process are presented. Modifications of Suncor's loss control management program to integrate with the environmental diligence program are also noted. 2 refs

  3. The Utilization of Amide Groups To Expand and Functionalize Metal-Organic Frameworks Simultaneously.

    Science.gov (United States)

    Lu, Zhiyong; Bai, Junfeng; Hang, Cheng; Meng, Fei; Liu, Wenlong; Pan, Yi; You, Xiaozeng

    2016-04-25

    A new stepwise ligand-elongation strategy by amide spacers is utilized to prepare isoreticularly high-porous metal-organic frameworks (MOFs), namely, quasi-mesoporous [Cu2 (PDBAD)(H2 O)]n (H4 PDBAD=5,5'-((4,4'-((pyridine-3,5-dicarbonyl)bis(azanediyl))bis(benzoyl))bis(azanediyl))diisophthalic acid; NJU-Bai22: NJU-Bai for Nanjing University Bai's group), and mesoporous [Cu2 (PABAD)(H2 O)]n (H4 PABAD=5,5'-((4,4'-((4,4'-((pyridine-3,5-dicarbonyl)bis(azanediyl))bis(benzoyl))bis (azanediyl))bis(benzoyl))bis(azanediyl))diisophthalic acid; NJU-Bai23). Compared with the prototypical MOF of [Cu2 (PDAD)(H2 O)]n (H4 PDAD=5,5'-(pyridine-3,5-dicarbonyl)bis(azanediyl)diisophthalic acid; NJU-Bai21, also termed as PCN-124), both MOFs exhibit almost the same CO2 adsorption enthalpy and CO2 selectivity values, and better capacity for CO2 storage under high pressure; these results make them promising candidate materials for CO2 capture and sequestration. Interestingly, this new method, in comparison with traditional strategies of using phenyl or triple-bond spacers, is easier and cheaper, resulting in a better ability to retain high CO2 affinity and selectivity in MOFs with large pores and high CO2 storage capacity. Additionally, it may lead to the high thermal stability of the MOFs and also their tolerance to water, which is related to the balance between the density of functional groups and pore sizes. Therefore, this strategy could provide new opportunities to explore more functionalized mesoporous MOFs with high performance. PMID:27031809

  4. Phosphor Dysprosium-Doped Layered Double Hydroxides Exchanged with Different Organic Functional Groups

    Directory of Open Access Journals (Sweden)

    David Ricardo Martínez Vargas

    2013-01-01

    Full Text Available The layers of a Zn/Al layered double hydroxide (LDH were doped with Dy3+ cations. Among some compositions, the Zn2+ : Al3+ : Dy3+ molar ratio equal to 30 : 9 : 1 presented a single crystalline phase. Organic anions with carboxylic, amino, sulfate, or phosphate functional groups were intercalated as single layers between LDH layers as confirmed by X-ray diffraction and infrared spectroscopy. Photoluminescence spectra of the nitrate intercalated LDH showed a wide emission band with strong intensity in the yellow region (around 574 nm, originated due to symmetry distortion of the octahedral coordination in dysprosium centers. Moreover, a broad red band emission was also detected apparently due to the presence of zinc oxide. The distorted symmetry of the dysprosium coordination environment, also confirmed by X-ray photoelectron spectroscopy analysis, was modified after the intercalation with phenyl phosphonate (PP, aspartate (Asp, adipate (Adip, and serinate (Ser anions; the emission as measured from PL spectra of these LDH was more intense in the blue region (ca. 486 nm, thus indicating an increase in symmetry of dysprosium octahedrons. The red emission band from zinc oxide kept the same intensity after intercalation of dodecyl sulfate (DDS. An additional emission of unknown origin at λ = 767 nm was present in all LDHs.

  5. EVA and its Determinants for Selected Groups of Farms: Conventional and Organic Farming

    Directory of Open Access Journals (Sweden)

    R. Aulová, M. Frýdlova

    2012-09-01

    Full Text Available This paper analyzes the economic value added, as well as its determining factors, for selected groups of agricultural enterprises - legal persons, farming in conventional and organic ways. The impact of the weighted average cost of capital to the value of EVA, as well as the efficient use of invested capital, including capital structure, in relation to farming, are both evaluated. The article also aims to verify the hypothesis that selected farms are able to achieve, without subsidies, particularly direct payments, positive economic value added and an efficient use of capital.The panel data set we use is drawn from the database of the Creditinfo Company Monitor, collected by Creditinfo Czech Republic, s.r.o. Specifically, we use information from the final accounts of chosen farms in the years 2006 - 2010. This paper is part of the research grant IGA 20121069, „Identification of the major determinants of the farm profits of legal persons and a determination of their specific characteristics”.

  6. Influence of high doses gamma radiation on group of meadow plants and water organisms

    International Nuclear Information System (INIS)

    The plot of 100 square meters area has been irradiated for 526 days by gamma radiation which simulated the external radiation of the local fall-out. This field experiment has been performed in specially preserved conditions. The organisms of land and water complexes present in this area have received the total of 50 000 R in the center and 600 R on periphery. It has been shown that: changes in the quantitative and qualitative composition of bacteria and soil and water fungi were generally little: among the physiological groups the greatest disfunctions have been observed for the bacteria of the nitric cycle; Lemna minor appeared to be the most radiosensitive water plant which perished completely in the zone around the center of the plot what in turn resulted in secondary changes in the composition of water microflora and micro- and macrofauna; the growth of 14 species of meadow plants present around the center of the plot has been reduced about 25% of biomass in comparison with the control plots; on the other hand, the stimulation of growth of meadow plants, mostly weeds, has been observed on the periphery of the plot. (author)

  7. Mutagenic Organized Recombination Process by Homologous IN vivo Grouping (MORPHING for directed enzyme evolution.

    Directory of Open Access Journals (Sweden)

    David Gonzalez-Perez

    Full Text Available Approaches that depend on directed evolution require reliable methods to generate DNA diversity so that mutant libraries can focus on specific target regions. We took advantage of the high frequency of homologous DNA recombination in Saccharomyces cerevisiae to develop a strategy for domain mutagenesis aimed at introducing and in vivo recombining random mutations in defined segments of DNA. Mutagenic Organized Recombination Process by Homologous IN vivo Grouping (MORPHING is a one-pot random mutagenic method for short protein regions that harnesses the in vivo recombination apparatus of yeast. Using this approach, libraries can be prepared with different mutational loads in DNA segments of less than 30 amino acids so that they can be assembled into the remaining unaltered DNA regions in vivo with high fidelity. As a proof of concept, we present two eukaryotic-ligninolytic enzyme case studies: i the enhancement of the oxidative stability of a H2O2-sensitive versatile peroxidase by independent evolution of three distinct protein segments (Leu28-Gly57, Leu149-Ala174 and Ile199-Leu268; and ii the heterologous functional expression of an unspecific peroxygenase by exclusive evolution of its native 43-residue signal sequence.

  8. Organic petrology and coalbed gas content, Wilcox Group (Paleocene-Eocene), northern Louisiana

    Science.gov (United States)

    Hackley, P.C.; Warwick, P.D.; Breland, F.C., Jr.

    2007-01-01

    Wilcox Group (Paleocene-Eocene) coal and carbonaceous shale samples collected from four coalbed methane test wells in northern Louisiana were characterized through an integrated analytical program. Organic petrographic analyses, gas desorption and adsorption isotherm measurements, and proximate-ultimate analyses were conducted to provide insight into conditions of peat deposition and the relationships between coal composition, rank, and coalbed gas storage characteristics. The results of petrographic analyses indicate that woody precursor materials were more abundant in stratigraphically higher coal zones in one of the CBM wells, consistent with progradation of a deltaic depositional system (Holly Springs delta complex) into the Gulf of Mexico during the Paleocene-Eocene. Comparison of petrographic analyses with gas desorption measurements suggests that there is not a direct relationship between coal type (sensu maceral composition) and coalbed gas storage. Moisture, as a function of coal rank (lignite-subbituminous A), exhibits an inverse relationship with measured gas content. This result may be due to higher moisture content competing for adsorption space with coalbed gas in shallower, lower rank samples. Shallower ( 600??m) coal samples containing less moisture range from under- to oversaturated with respect to their CH4 adsorption capacity.

  9. 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

  10. 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

  11. 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

  12. 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.

  13. 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.

  14. 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.

  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. 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

  17. 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

  18. Social organization of a stable natal group of captive Guyanese squirrel monkeys (Saimiri sciureus sciureus).

    Science.gov (United States)

    Bashaw, Meredith J; McIntyre, Chelsea; Salenetri, Nicole D

    2011-10-01

    Socioecological models suggest competition for food, foraging efficiency, predation, infanticide risk, and the costs of dispersal regulate primate social structure and organization. Wild populations of squirrel monkeys (Saimiri spp.) appear to conform to the predictions of the predation/competition socioecological model (Sterck et al. in Behav Ecol Sociobiol 41:291-309, 1997) and the dispersal/foraging efficiency model (Isbell in Kinship and behavior in primates. Oxford University, New York, pp 71-108, 2004). However, squirrel monkeys in captivity are reported to maintain patterns of social behavior observed in their wild conspecifics despite different food distribution, predation risk, and dispersal options. This behavioral similarity suggests squirrel monkeys' social behavior has limited flexibility to respond to environmental changes. In this study, we experimentally evaluated the flexibility of social behavior within a captive group of S. sciureus. First, we determined whether dominance and affiliative relationships observed under normal laboratory conditions (with abundant, widely distributed, food; no dispersal option; and no predators) better matched published reports of relationships among wild conspecifics or the predictions of the predation/competition model. Second, we made preferred food items defensible to determine whether dominance interactions would become more frequent and linear, as predicted by the model. The model correctly predicted rates of dominance behavior in both conditions and a linear hierarchy in the defensible food condition but did not predict the consistent affiliative relationships and linear dominance hierarchy observed in normal lab conditions. Although hierarchies were linear and male dominant, manipulating food distribution changed the dominant individual within each sex. Our findings suggest interaction rates adapt more rapidly than social structure to environmental changes in Saimiri and recommend caution in interpreting tests

  19. Prediction Of Organic Aerosol Volatility And Unidentified Functional Group Concentrations From Fourier Transform Infrared (FTIR) Spectroscopy Measurements

    Science.gov (United States)

    Ruggeri, G.; Shipley, S.; Henderson, B. H.; Takahama, S.

    2014-12-01

    Fourier Transform Infrared (FTIR) spectroscopy is used to measure the functional group composition of organic aerosols (Russell et al., 2011). However, certain functional groups are not directly detected by FTIR spectroscopy, either due to fundamental limitations of the technique (e.g. tertiary carbons), or specific limitations of commonly employed methods of sample collection and analysis (e.g. ester and ether groups, Takahama et al., 2013). In addition, FTIR does not probe the size of molecules comprising an organic aerosol mixture, which prevents the direct calculation of organic aerosol volatility from FTIR measurements. In this study, primary organic aerosol concentrations in mixtures corresponding to different ambient scenarios have been extracted from previous GC-MS studies (Rogge et al., 1993). Secondary organic aerosol concentrations for different scenarios are simulated with an explicit chemistry model (Master Chemical Mechanism, http://mcm.leeds.ac.uk/MCM ; Jerkin et al. 1997; Saunders et al., 2003; Jerkin et al., 2003) and partitioning model (SIMPOL.1, Pankow et al., 2008). For each of the different scenarios the concentrations of functional groups that are typically accessible by FTIR are calculated and analyzed in relation to the extra information not easily accessible by FTIR (e.g. volatility, tertiary carbons, ester and ether). The ability to predict the unknown quantities from FTIR measurements and thereby reduce the uncertainty in OM concentrations and OM/OC ratios measured by FTIR is examined and discussed.

  20. 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

  1. 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.

  2. 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...

  3. The Impact of Conservation Management on the Community Composition of Multiple Organism Groups in Eutrophic Interconnected Man-Made Ponds

    OpenAIRE

    Lemmens, P.; Mergeay, J.; Van Wichelen, J.; De Meester, Luc; Declerck, S.A.J.

    2015-01-01

    Ponds throughout the world are subjected to a variety of management measures for purposes of biodiversity conservation. Current conservation efforts typically comprise a combination of multiple measures that directly and indirectly impact a wide range of organism groups. Knowledge of the relative impact of individual measures on different taxonomic groups is important for the development of effective conservation programs. We conducted a field study of 28 man-made ponds, representing four man...

  4. Attitudes and beliefs about deceased organ donation in the Arabic-speaking community in Australia: a focus group study

    OpenAIRE

    Ralph, Angelique F; Alyami, Ali; Allen, Richard D M; Howard, Kirsten; Craig, Jonathan C.; Chadban, Steve J; Irving, Michelle; Tong, Allison

    2016-01-01

    Objectives To describe the beliefs and attitudes to organ donation in the Arabic-speaking community. Design Arabic-speaking participants were purposively recruited to participate in 6 focus groups. Transcripts were analysed thematically. Participants 53 participants, aged 19–77 years, and originating from 8 countries, participated in 1 of 6 focus groups. Participants identified as Christian (73%), Islam (26%), Buddhist (2%) or did not identify with any religion (2%). Results 6 themes (with su...

  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. End-group-directed self-assembly of organic compounds useful for photovoltaic applications

    Energy Technology Data Exchange (ETDEWEB)

    Beaujuge, Pierre M.; Lee, Olivia P.; Yiu, Alan T.; Frechet, Jean M.J.

    2016-05-31

    The present invention provides for an organic compound comprising electron deficient unit covalently linked to two or more electron rich units. The present invention also provides for a device comprising the organic compound, such as a light-emitting diode, thin-film transistor, chemical biosensor, non-emissive electrochromic, memory device, photovoltaic cells, or the like.

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. 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...

  17. 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.

  18. 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

  19. 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

  20. Use of organic functional group concentrations as a means of screening for energetics

    International Nuclear Information System (INIS)

    One of the safety concerns associated with the waste tanks on the Hanford site is the presence of organics in a highly oxidizing environment that could potentially act as a fuel source to maintain a propagating reaction. To determine this risk, it is necessary to determine the amount of high enthalpy organics present in the tanks. Currently, the primary ways of obtaining this information are to either rely on tank-fill histories, which are often unreliable and do not account for waste-aging processes, or obtain samples from the tank and speciate the organics present through a series of analytical procedures. While organic speciation has been successful in providing very valuable information about organics present in the tanks and the waste aging processes that are occurring in general, it can be costly and time consuming analyzing a large number of waste tanks. Differential scanning calorimetry has previously been used to obtain heat of reaction measurements of Hanford tank waste samples. However, differential scanning calorimetry is shown here to inadequately measure calculated heats of reaction of simulant tank mixtures. Overall, the preliminary results presented here, suggest that indeed Fourier transform infrared and Raman spectroscopy would be useful screening tools for determination of C-H and COO- organic content in tank waste samples analyzed in a hot cell environment. These techniques however, are not truly quantitative for this application and would be primarily used for identifying tanks of potential safety concern that would require further, more detailed confirmatory analysis by organic speciation techniques

  1. Multifractality to Photonic Crystal & Self-Organization to Metamaterials through Anderson Localizations & Group/Gauge Theory

    Science.gov (United States)

    Hidajatullah-Maksoed, Widastra

    2015-04-01

    Arthur Cayley at least investigate by creating the theory of permutation group[F:∖∖Group_theory.htm] where in cell elements addressing of the lattice Qmf used a Cayley tree, the self-afine object Qmf is described by the combination of the finite groups of rotation & inversion and the infinite groups of translation & dilation[G Corso & LS Lacena: ``Multifractal lattice and group theory'', Physica A: Statistical Mechanics &Its Applications, 2005, v 357, issue I, h 64-70; http://www.sciencedirect.com/science/articel/pii/S0378437105005005 ] hence multifractal can be related to group theory. Many grateful Thanks to HE. Mr. Drs. P. SWANTORO & HE. Mr. Ir. SARWONO KUSUMAATMADJA.

  2. The Socialization Process of Street Children in the Youth Gangs and Groups of Organized Crime in Local Community. Preliminary Report

    Directory of Open Access Journals (Sweden)

    Małgorzata Michel

    2013-12-01

    Full Text Available This article includes the research report on the socialization process of children in the street, youth gangs, and organized criminal groups in local communities. The author has analysed the signs and communication codes located on walls in local communities. This is very important to the socialization process of the youth street gangs.

  3. Biogenic oxidized organic functional groups in aerosol particles from a mountain forest site and their similarities to laboratory chamber products

    Directory of Open Access Journals (Sweden)

    R. E. Schwartz

    2010-06-01

    Full Text Available Submicron particles collected at Whistler, British Columbia, at 1020 m a.s.l. during May and June 2008 on Teflon filters were analyzed by Fourier transform infrared (FTIR and X-ray fluorescence (XRF techniques for organic functional groups (OFG and elemental composition. Organic mass (OM concentrations ranged from less than 0.5 to 3.1 μg m−3, with a project mean and standard deviation of 1.3±1.0 μg m−3 and 0.21±0.16 μg m−3 for OM and sulfate, respectively. On average, organic hydroxyl, alkane, and carboxylic acid groups represented 34%, 33%, and 23% of OM, respectively. Ketone, amine and organosulfate groups constituted 6%, 5%, and <1% of the average organic aerosol composition, respectively. Measurements of volatile organic compounds (VOC, including isoprene and monoterpenes from biogenic VOC (BVOC emissions and their oxidation products (methyl-vinylketone / methacrolein, MVK/MACR, were made using co-located proton transfer reaction mass spectrometry (PTR-MS. We present chemically-specific evidence of OFG associated with BVOC emissions. Positive matrix factorization (PMF analysis attributed 65% of the campaign OM to biogenic sources, based on the correlations of one factor to monoterpenes and MVK/MACR. The remaining fraction was attributed to anthropogenic sources based on a correlation to sulfate. The functional group composition of the biogenic factor (consisting of 32% alkane, 25% carboxylic acid, 21% organic hydroxyl, 16% ketone, and 6% amine groups was similar to that of secondary organic aerosol (SOA reported from the oxidation of BVOCs in laboratory chamber studies, providing evidence that the magnitude and chemical composition of biogenic SOA simulated in the laboratory is similar to that found in actual atmospheric conditions. The biogenic factor OM is also correlated to dust elements, indicating that dust may act as a non-acidic SOA sink. This role is supported by the organic functional

  4. The role of bridging organizations in environmental management: examining social networks in working groups

    OpenAIRE

    Adam A. Kowalski; Jenkins, Lekelia D.

    2015-01-01

    The linkage of diverse sets of actors and knowledge systems across management levels and institutional boundaries often poses one of the greatest challenges in adaptive management of natural resources. Bridging organizations can facilitate interactions among actors in management settings by lowering the transaction costs of collaboration. The Center for Ocean Solutions (COS) is an example of a bridging organization that is focused on linking actors within the ocean sciences and governance are...

  5. Seeking Shared Practice: A Juxtaposition of the Attributes and Activities of Organized Fossil Groups with Those of Professional Paleontology

    Science.gov (United States)

    Crippen, Kent J.; Ellis, Shari; Dunckel, Betty A.; Hendy, Austin J. W.; MacFadden, Bruce J.

    2016-05-01

    This study sought to define the attributes and practices of organized fossil groups (e.g., clubs, paleontological societies) as amateur paleontologists, as well as those of professional paleontologists, and explore the potential for these two groups to work collaboratively as a formalized community. Such an investigation is necessary to develop design principles for an online environment that supports this community and encourages communication and shared practice among individuals with different backgrounds in paleontology and who are geographically isolated. A national survey of fossil group representatives and professional paleontologists was used to address the research questions. The results provide a rich description of the attributes and activities of both groups and are discussed in terms of three design principles for supporting the two groups in a form of collaboration and fellowship via a coherent shared practice within an online learning community.

  6. A Behavior Analysis of Individuals' Use of the Fairness Heuristic when Interacting with Groups and Organizations

    Science.gov (United States)

    Goltz, Sonia M.

    2013-01-01

    In the present analysis the author utilizes the groups as patches model (Goltz, 2009, 2010) to extend fairness heuristic theory (Lind, 2001) in which the concept of fairness is thought to be a heuristic that allows individuals to match responses to consequences they receive from groups. In this model, individuals who are reviewing possible groups…

  7. The petrology, organic geochemistry and palynology of Tertiary Age Eureka Sound Group coals, Arctic Canada

    Energy Technology Data Exchange (ETDEWEB)

    Kalkreuth, W.; Keuser, C.; Fowler, M.; Li, M.; McIntyre, D.; Puttmann, W.; Richardson, R.

    1998-12-31

    Tertiary age lignites from Arctic Canada were analysed by petrographical, palynological and organic geochemical methods. Results from petrographic analyses indicate the predominance of wood-derived macerals in seams from the Strathcona and Stenkul Fiord areas, whereas in the Bache Peninsula area many seams are characterized by the predominance of detrital macerals and have also higher inertinite contents. Palynological assemblages are dominated by Taxodiaceae pollen. Organic geochemical results indicate that norisopimarane and pimarane are the most abundant diterpenoids. The depositional environment at Strathcona and Stenkul Fiords was that of a forested swamp, which formed in a lagoonal/alluvial plain setting. At Bache Peninsula the mire was less forested.

  8. 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.

  9. 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.

  10. Two distinct groups of non-attenders in an organized mammography screening program

    DEFF Research Database (Denmark)

    Aro, A R; de Koning, H J; Absetz, P;

    2001-01-01

    OBJECTIVE: To find out reasons for non-attendance and to study subgroup differences of the non-attenders in an organized mammography screening program. DESIGN: Prospective for background and psychosocial factors, retrospective for reasons of non-attendance. SETTING: Finnish screening based...

  11. Reading for Change: Social Justice Unionism Book Groups as an Organizing Tool

    Science.gov (United States)

    Riley, Kathleen

    2015-01-01

    Kathleen Riley begins this article by providing quotes from James H. Lytle, and Anissa Weinraub, which were published in "Perspectives on Urban Education" in the summer of 2013. While they hold different professional positions (Lytle is a retired administrator and professor; Weinraub is a teacher and organizer), both wrote as…

  12. Qualitative Organic Analysis: An Efficient, Safer, and Economical Approach to Preliminary Tests and Functional Group Analysis

    Science.gov (United States)

    Dhingra, Sunita; Angrish, Chetna

    2011-01-01

    Qualitative organic analysis of an unknown compound is an integral part of the university chemistry laboratory curriculum. This type of training is essential as students learn to approach a problem systematically and to interpret the results logically. However, considerable quantities of waste are generated by using conventional methods of…

  13. Group Work in a Classroom: An Analogy with Organisms in a Community

    Science.gov (United States)

    Šorgo, Andrej

    2007-01-01

    There is a large number of relationships between organisms in communities, and these relationships comprise the following types: predation and parasitism, commensalism, protocooperation and mutualism, neutralism, amensalism, and competition. The possible effects of the relationship between two species are that one or the other can benefit (+),…

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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

  20. 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

  1. 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.

  2. 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

  3. 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...

  4. 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

  5. Why it is hard to support group work in distributed healthcare organizations: empirical knowledge of the social-technical gap.

    Science.gov (United States)

    Weng, Chunhua

    2005-01-01

    We used a participatory design process to understand and to support the group work of cancer clinical trial protocol design within a distributed organization, the Southwest Oncology Group (SWOG). We also designed a collaborative writing system to facilitate its protocol reviewing and revising processes over the Internet. After a series of iterative prototyping and formative evaluations over the past two years, we identified a social-technical gap in our group work support research at SWOG. This gap consists of technical challenges, expanding user needs, conflicting user needs from different roles, insufficient incentive for using groupware technology by certain members, subtle organizational nuances, and the changing organizational structure. This paper describes our longitudinal evaluations results and elaborates on the social-technical gap. We think this gap may generalize to other healthcare group work settings. PMID:16779151

  6. Demography-based adaptive network model reproduces the spatial organization of human linguistic groups

    Science.gov (United States)

    Capitán, José A.; Manrubia, Susanna

    2015-12-01

    The distribution of human linguistic groups presents a number of interesting and nontrivial patterns. The distributions of the number of speakers per language and the area each group covers follow log-normal distributions, while population and area fulfill an allometric relationship. The topology of networks of spatial contacts between different linguistic groups has been recently characterized, showing atypical properties of the degree distribution and clustering, among others. Human demography, spatial conflicts, and the construction of networks of contacts between linguistic groups are mutually dependent processes. Here we introduce an adaptive network model that takes all of them into account and successfully reproduces, using only four model parameters, not only those features of linguistic groups already described in the literature, but also correlations between demographic and topological properties uncovered in this work. Besides their relevance when modeling and understanding processes related to human biogeography, our adaptive network model admits a number of generalizations that broaden its scope and make it suitable to represent interactions between agents based on population dynamics and competition for space.

  7. Demography-based adaptive network model reproduces the spatial organization of human linguistic groups.

    Science.gov (United States)

    Capitán, José A; Manrubia, Susanna

    2015-12-01

    The distribution of human linguistic groups presents a number of interesting and nontrivial patterns. The distributions of the number of speakers per language and the area each group covers follow log-normal distributions, while population and area fulfill an allometric relationship. The topology of networks of spatial contacts between different linguistic groups has been recently characterized, showing atypical properties of the degree distribution and clustering, among others. Human demography, spatial conflicts, and the construction of networks of contacts between linguistic groups are mutually dependent processes. Here we introduce an adaptive network model that takes all of them into account and successfully reproduces, using only four model parameters, not only those features of linguistic groups already described in the literature, but also correlations between demographic and topological properties uncovered in this work. Besides their relevance when modeling and understanding processes related to human biogeography, our adaptive network model admits a number of generalizations that broaden its scope and make it suitable to represent interactions between agents based on population dynamics and competition for space. PMID:26764748

  8. 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

  9. 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

  10. 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

  11. Development and Analysis of Group Contribution Plus Models for Property Prediction of Organic Chemical Systems

    DEFF Research Database (Denmark)

    Mustaffa, Azizul Azri

    and further development of the GCPlus approach for predicting mixture properties to be called the UNIFAC-CI model. The contributions of this work include an analysis of the developed Original UNIFAC-CI model in order to investigate why the model does not perform as well as the reference UNIFAC model......Prediction of properties is important in chemical process-product design. Reliable property models are needed for increasingly complex and wider range of chemicals. Group-contribution methods provide useful tool but there is a need to validate them and improve their accuracy when complex chemicals...... are present in the mixtures. In accordance with that, a combined group-contribution and atom connectivity approach that is able to extend the application range of property models has been developed for mixture properties. This so-called Group-ContributionPlus (GCPlus) approach is a hybrid model which...

  12. Method of applied information theory in estimating efficiency of structural organization of small group of aviation operators

    Directory of Open Access Journals (Sweden)

    О. М. Рева

    1999-09-01

    Full Text Available Substantiated is the possibility of applying cybernetic methods of information chains for analy­sis of efficiency of structural organization of dispatcher team. To investigate it we have composed and solved a system of 10th order linear equation (used are direct current information chains . It is proved that the general scheme must be decomposed, on the one hand, into a group of operative planning and management on the other hand. Worked out are the requirement to the group members

  13. Influence of social mixing and group size on skin lesions and mounting in organic entire male pigs

    DEFF Research Database (Denmark)

    Thomsen, Rikke; Edwards, Sandra A; Rousing, Tine;

    2016-01-01

    management procedures and production system might be needed. Elements from the organic pig production system might be beneficial in this aspect. The aim of this article is to investigate the effect of grouping strategy including social mixing and group size on levels of mounting behaviour and skin lesions......Alternatives to surgical castration are needed, due to stress and pain caused by castration of male pigs. One alternative is production of entire male pigs. However, changed behaviour of entire males compared with castrated males might adversely affect the welfare of entire males and changes in...

  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. Sensory Experiences and Expectations of Organic Food. Results of Focus Group Discussions

    OpenAIRE

    Stolz, Hanna; Jahrl, Ingrid; Baumgart, Lukas; Schneider, Flurina

    2010-01-01

    This executive summary describes the main objectives and findings from a qualitative survey on consumers’ sensory experiences, expectations and preferences with respect to organic food. The survey was conducted in the frame of the European Commission funded project ECROPOLIS in 2009 in Germany (DE), France (FR), Italy (IT), Netherlands (NL), Poland (PL) and Switzerland (CH). The objectives of this research were to explore: - the range of experiences, expectations and preferences for specif...

  20. EFFECTS OF DIFFERENT FUNCTIONAL GROUP-CONTAINING ORGANICS ON MORPHOLOGY-CONTROLLED SYNTHESIS OF SILVER NANOPARTICLES AT ROOM TEMPERATURE

    Institute of Scientific and Technical Information of China (English)

    A.L. Wang; H.B. Yin; M. Ren; X.N. Cheng; Q.F. Zhou; X.F. Zhang

    2006-01-01

    Silver nanoparticles with average particles sizes ranging from 2 to 131nm were manipulatively synthesized starting from silver nitrate using different functional group-containing organic modifiers at room temperature. The effects of the organic modifiers on the morphology of the resulting silver nanoparticles were strongly dependent on the intrinsic properties of the functional groups and the reducibility of the reductant. Numerous ether bonds (-O-) present in polyethylene glycol and Tween-80 were beneficial to the formation of silver nanoparticles with particle sizes of several nanometers in a narrow size distribution in both weak and strong reducing environments.Cetyltrimethylammonium bromide induced the formation of nanosized silver triangle plates in a weak reducing environment. The crystal growth of the silver nanoparticles with particle sizes of more than 10nm was postulated through an adhesion process of small-sized particles followed by a subsequent coalescence process under the present reaction conditions.

  1. One Hand Washes Another : Informal Ties Between Organized Criminal Groups and Law-Enforcement Agencies in Russia

    Directory of Open Access Journals (Sweden)

    Alexey Konnov

    2006-11-01

    Full Text Available This article discusses the forms, contents and peculiarities of the existing informal ties between members of organized criminal groups and representatives of law-enforcement agencies in the Tatarstan Republic of Russia. Particular attention is paid to the origins of informal ties; ways how these relations are established, maintained, and utilized by both parts; causes of corruption in the law-enforcement agencies and the possibilities to understand it. The main conclusions are based on the results of ninety-six in-depth interviews with the law-enforcement officers, businessmen, members of organized criminal groups, and journalists conducted in main cities and towns of the Tatarstan Republic under support of the Transnational Crime and Corruption Centre at American University.

  2. Transformation Education: A Vehicle for Structuring Group Care Organizations to Increase Service Quality and Effectiveness

    Science.gov (United States)

    Ross, Andrew L.

    2007-01-01

    Transformation Education, an organizational philosophy and operating system, is designed to increase service quality and effectiveness of group care through aligning its organizational structure with its purpose. This alignment is achieved through creating a culture designed to dispense transformation rather than treatment. The author presents how…

  3. Using Groups to Change the Department Head Role: An Organization Development Case

    Science.gov (United States)

    LeBlanc, Sheila; London, Chad; Huisman, Jeroen

    2013-01-01

    This article provides a detailed description and analysis of how one Canadian institution used groups of department heads as change agents to address their most acute department head role tensions. It is demonstrated that this institution's change initiative aligned very closely to the recommendations proposed, in both the literature pertaining to…

  4. Two-dimensional ordered cluster analysis of component groups in self-organization

    Directory of Open Access Journals (Sweden)

    WenJun Zhang

    2014-09-01

    Full Text Available An algorithm for two-dimensional cluster analysis of component groups, originally from Zhang et al., (2004, was introduced in this study. The algorithm composes of three procedures, i.e., calculation of distance measures, randomization statistic test, and ordered clustering of components.

  5. 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.

  6. 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

  7. 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

  8. Ultra-thin films of polysilsesquioxanes possessing 3-methacryloxypropyl groups as gate insulator for organic field-effect transistors

    International Nuclear Information System (INIS)

    Polysilsesquioxanes (PSQs) possessing 3-methacryloxypropyl groups as an organic moiety of the side chain were synthesized by sol–gel condensation copolymerization of the corresponding trialkoxysilanes. The ultra-thin PSQ film with a radical initiator and a cross-linking agent was prepared by a spin-coating method, and the film was cured integrally at low temperatures of less than 120 °C through two different kinds of polymeric reactions, which were radical polymerization of vinyl groups and sol–gel condensation polymerization of terminated silanol and alkoxy groups. The obtained PSQ film showed the almost perfect solubilization resistance to acetone, which is a good solvent of PSQ before polymerization. It became clear by atomic force microscopy observation that the surface of the PSQ film was very smooth at a nano-meter level. Furthermore, pentacene-based organic field-effect transistor (OFET) with the PSQ film as a gate insulator showed typical p-channel enhancement mode operation characteristics and therefore the ultra-thin PSQ film has the potential to be applicable for solution-processed OFET systems. - Highlights: ► Polysilsesquioxanes (PSQs) possessing 3-methacryloxypropyl groups were synthesized. ► The ultra-thin PSQ film could be cured at low temperatures of less than 120 °C. ► The PSQ film showed the almost perfect solubilization resistance to organic solvent. ► The surface of the PSQ film was very smooth at a nano-meter level. ► Pentacene-based organic field-effect transistor with the PSQ film was fabricated.

  9. Determination of thiol functional groups on bacteria and natural organic matter in environmental systems

    Energy Technology Data Exchange (ETDEWEB)

    Anandha Rao, Balaji [ORNL; Lin, Hui [ORNL; Liang, Liyuan [ORNL; Gu, Baohua [ORNL

    2014-01-01

    Organic thiols (R-SH) are known to react and form complexes with some toxic soft metals such as mercury (Hg) in both biotic and abiotic systems. However, a clear understanding of these interactions is currently limited because quantifying thiols in environmental matrices is difficult due to their low abundance, susceptibility to oxidation, and measurement interference by non-thiol compounds in samples. Here, we report a fluorescence-labeling method using a maleimide containing probe, ThioGlo-1 (TG-1), to determine total thiols directly on bacterial cells and natural organic matter (NOM). We systematically evaluated the optimal thiol labeling conditions and interference from organic compounds such as disulfide, methionine, thiourea, and amine, and inorganic ions such as Na+, K+, Ca2+, Fe2+, Cl-, SO42-, HCO3-, and SCN-, and found that the method is highly sensitive and selective. Only relatively high levels of sulfide (S2-) and sulfite (SO32-) significantly interfere with the thiol analysis. The method was successful in determining thiols in a bacterium Geobacter sulfurreducens PCA and its mutants in a phosphate buffered saline solution. The measured value of ~2.1 104 thiols cell-1 (or ~0.07 mol g-1 wet cells) is in good agreement with that observed during reactions between Hg and PCA cells. Using the standard addition, we determined the total thiols of two reference NOM samples, the reduced Elliot soil humic acid and Suwanee River NOM, to be 3.6 and 0.7 mol g-1, respectively, consistent with those obtained based on their reactions with Hg.

  10. Renormalization group and instantons in stochastic nonlinear dynamics, from self-organized criticality to thermonuclear reactors

    International Nuclear Information System (INIS)

    Stochastic counterparts of nonlinear dynamics are studied by means of nonperturbative functional methods developed in the framework of quantum field theory (QFT). In particular, we discuss fully developed turbulence, including leading corrections on possible compressibility of fluids, transport through porous media, theory of waterspouts and tsunami waves, stochastic magnetohydrodynamics, turbulent transport in crossed fields, self-organized criticality, and dynamics of accelerated wrinkled flame fronts advancing in a wide canal. This report would be of interest to the broad auditorium of physicists and applied mathematicians, with a background in nonperturbative QFT methods or nonlinear dynamical systems, having an interest in both methodological developments and interdisciplinary applications. (author)

  11. Motivation of employees in the organization - case study of AAA auto group

    OpenAIRE

    Vznuzdaeva, Anastasia

    2013-01-01

    This bachelor thesis deals with the matter of motivation in AAA Auto Group N.V. Work considers motivation as one of possibilities to effectively lead people and achieve outcomes. The work consists of two parts. The first part is a theoretical that talks about the management and its administrative functions, describes motivation and stimulation patterns, characterizes different theories of motivation and management strategies for increasing motivation. The second part of the work concentrat...

  12. Mindfulness for group facilitation:An example of Eastern philosophy in Western organizations

    OpenAIRE

    Adriansen, Hanne Kirstine; Krohn, Simon

    2014-01-01

    In this paper, we argue that mindfulness techniques can be used for enhancing the outcome of group performance. The word mindfulness has different connotations in the academic literature. Broadly speaking there is ‘mindfulness without meditation’ or ‘Western’ mindfulness which involves active thinking and ‘Eastern’ mindfulness which refers to an open, accepting state of mind, as intended with Buddhist-inspired techniques such as meditation. In this paper, we are interested in the latter type ...

  13. [Peculiarities of structure-function organization of microbial groups of soil contaminated by cement dust].

    Science.gov (United States)

    Stefurak, V P

    2001-01-01

    Long-term contamination of the forest soil by the cement dust leads to disturbances of stability of natural microbial groups, changes their quantitative and qualitative composition, results in substitution of some microbial associations by other ones. The intensive contamination of the soil by the effluents of cement integrated works, inhibits the intensity of nitrogen fixation processes and decay of the forest litter, development of micromycetes, results in the decrease of the length of mycelium and its biomass. PMID:11692672

  14. Walking Down the Chalcogenic Group of the Periodic Table: From Singlet to Triplet Organic Emitters.

    Science.gov (United States)

    Kremer, Adrian; Aurisicchio, Claudia; De Leo, Federica; Ventura, Barbara; Wouters, Johan; Armaroli, Nicola; Barbieri, Andrea; Bonifazi, Davide

    2015-10-19

    The synthesis, X-ray crystal structures, ground- and excited-state UV/Vis absorption spectra, and luminescence properties of chalcogen-doped organic emitters equipped on both extremities with benzoxa-, benzothia-, benzoselena- and benzotellurazole (1X and 2X ) moieties have been reported for the first time. The insertion of the four different chalcogen atoms within the same molecular skeleton enables the investigation of only the chalcogenic effect on the organisation and photophysical properties of the material. Detailed crystal-structure analyses provide evidence of similar packing for 2O -2Se , in which the benzoazoles are engaged in π-π stacking and, for the heavier atoms, in secondary X⋅⋅⋅X and X⋅⋅⋅N bonding interactions. Detailed computational analysis shows that the arrangement is essentially governed by the interplay of van der Waals and secondary bonding interactions. Progressive quenching of the fluorescence and concomitant onset of phosphorescence features with gradually shorter lifetimes are detected as the atomic weight of the chalcogen heteroatom increases, with the tellurium-doped derivatives exhibiting only emission from the lowest triplet excited state. Notably, the phosphorescence spectra of the selenium and tellurium derivatives can be recorded even at room temperature; this is a very rare finding for fully organic emitters. PMID:26471446

  15. Self-organizing p-quinquephenyl building blocks incorporating lateral hydroxyl and methoxyl groups into supramolecular nano-assemblies.

    Science.gov (United States)

    Lu, Zhaoyang; Zhong, Keli; Liu, Yang; Li, Zhaohua; Chen, Tie; Jin, Long Yi

    2016-05-01

    The self-assembling behavior of coil-rod-coil molecules 1a, 1b, and 2a, 2b was investigated using DSC, POM, SAXS, and AFM in bulk and aqueous solutions. These molecules contain p-quinquephenyl groups as rod segments incorporating lateral hydroxyl or methoxyl groups in the center positions and oligo(ethylene oxide)s as the coil segments. Molecules 1a and 1b, with lateral methoxyl groups in the rod segments, self-assemble into oblique columnar structures in the crystalline phase and transform into nematic phases. On the other hand, molecules 2a and 2b, with hydroxyl groups in the center of their rod segments, self-organize into hexagonal perforated lamellar and oblique columnar nano-structures in the crystalline and liquid crystalline phase, respectively. In aqueous solutions, these molecules aggregate into nano-ribbons and vesicles, depending on their lateral groups and oligo(ethylene oxide) chain lengths. These results imply that the lateral methoxyl or hydroxyl groups, present in the center of the rod segments, significantly influence the formation of various supramolecular nano-structures in the bulk state and in aqueous solution. This is achieved via tuning of the non-covalent interactions of the rod building blocks. PMID:27025276

  16. Highly porous organic polymers bearing tertiary amine group and their exceptionally high CO2 uptake capacities

    International Nuclear Information System (INIS)

    We report a very simple and unique strategy for synthesis of a tertiary amine functionalized high surface area porous organic polymer (POP) PDVTA-1 through the co-polymerization of monomers divinylbenzene (DVB) and triallylamine (TAA) under solvothermal reaction conditions. Two different PDVTA-1 samples have been synthesized by varying the molar ratio of the monomers. The porous polymeric materials have been thoroughly characterized by solid state 13C CP MAS-NMR, FT-IR and UV–vis spectroscopy, N2 sorption, HR TEM and FE SEM to understand its chemical environment, nanostructure, bonding, morphology and related surface properties. PDVTA-1 with higher amine content (DVB/TAA=4.0) showed exceptionally high CO2 uptake capacity of 85.8 wt% (19.5 mmol g−1) at 273 K and 43.69 wt% (9.93 mmol g−1) at 298 K under 3 bar pressure, whereas relatively low amine loaded material (DVB/TAA=7.0) shows uptake capacity of 59.2 wt% (13.45 mmol g−1) at 273 K and 34.36 wt% (7.81 mmol g−1) at 298 K. Highly porous nanostructure together with very high surface area and basicity at the surface due to the presence of abundant basic tertiary amine N-sites in the framework of PDVTA-1 could be responsible for very high CO2 adsorption. - Graphical abstract: Exceptionally high CO2 uptake (85.8 wt % at 273 K) has been observed over a high surface area porous organic polymer PDVTA-1 synthesized through copolymerization of divinylbenzene and triallyl amine. - Highlights: • Designing the synthesis of a new N-rich cross-linked porous organic polymer PDVTA-1. • PDVTA-1 showed mesoporosity with very high surface area of 903 m2 g−1. • High surface area and presence of basic sites facilitates the CO2 uptake. • PDVTA-1 showed exceptionally high CO2 adsorption capacity of 85.8 wt% at 273 K, 3 bar pressure

  17. Blue emitting fluorophores of phenyleneethynylenes substituted by diphenylethenyl terminal groups for organic light-emitting diodes

    International Nuclear Information System (INIS)

    Phenyleneethynylene motifs substituted by diphenylethenyl groups at both ends were prepared successfully by use of double elimination protocol of β-substituted sulfones for introducing phenyleneethynylene arrays followed by Wittig-Horner reaction for introducing diphenylethenyl moiety. The hybrid blue fluorophores exhibited strong emission even in the solid-state films (ΦF ≥ 0.60) while, in CHCl3 solution, incorporation of substituents on the central phenylene unit significantly enhanced emission efficiency up to ΦF = 0.57. The OLED devices with use of these blue fluorophores as an emitting material provided maximum external quantum efficiency of ηext = 2.4%

  18. Solubility studies of inorganic–organic hybrid nanoparticle photoresists with different surface functional groups

    KAUST Repository

    Li, Li

    2016-01-01

    © 2016 The Royal Society of Chemistry. The solubility behavior of Hf and Zr based hybrid nanoparticles with different surface ligands in different concentrations of photoacid generator as potential EUV photoresists was investigated in detail. The nanoparticles regardless of core or ligand chemistry have a hydrodynamic diameter of 2-3 nm and a very narrow size distribution in organic solvents. The Hansen solubility parameters for nanoparticles functionalized with IBA and 2MBA have the highest contribution from the dispersion interaction than those with tDMA and MAA, which show more polar character. The nanoparticles functionalized with unsaturated surface ligands showed more apparent solubility changes after exposure to DUV than those with saturated ones. The solubility differences after exposure are more pronounced for films containing a higher amount of photoacid generator. The work reported here provides material selection criteria and processing strategies for the design of high performance EUV photoresists.

  19. How can one measure group cohesion? From individual organisms to their interaction

    CERN Document Server

    Di, Z; Lu, X; Li, G; Roehner, B M; Suematsu, N J; Yepremian, C

    2014-01-01

    Measuring atomic and molecular interactions was one of the main objectives of physics during the past century. It was an essential step not only in itself but because most macroscopic properties can be derived once one knows interaction strengths. At the present time, except for systems that can be described as discrete networks (like the Internet network) our knowledge of social and biological ties still remains very limited. An important step is to develop experimental means for measuring social and biological interactions. In this talk there are two parts. Firstly, we describe experimental evidence of inter-individual attraction in populations of insects. Secondly, we focus on a specific system, namely populations of Euglena gracilis, a green, swimming unicellular organism, for which we try to determine individual and interaction properties.

  20. Isolation of Hypervalent Group-16 Radicals and Their Application in Organic-Radical Batteries.

    Science.gov (United States)

    Imada, Yasuyuki; Nakano, Hideyuki; Furukawa, Ko; Kishi, Ryohei; Nakano, Masayoshi; Maruyama, Hitoshi; Nakamoto, Masaaki; Sekiguchi, Akira; Ogawa, Masahiro; Ohta, Toshiaki; Yamamoto, Yohsuke

    2016-01-20

    Using a newly prepared tridentate ligand, we isolated hypervalent sulfur and selenium radicals for the first time and characterized their structures. X-ray crystallography, electron spin resonance spectroscopy, and density functional theory calculations revealed a three-coordinate hypervalent structure. Utilizing the reversible redox reactions between hypervalent radicals and the corresponding anions bearing Li(+), we developed organic radical batteries with these compounds as cathode-active materials. Furthermore, an all-radical battery, with these compounds as the cathode and a silyl radical as the anode, was developed that exhibited a practical discharge potential of ∼ 1.8 V and stable cycle performance, demonstrating the potential of these materials for use in metal-free batteries that can replace conventional Li-ion batteries where Li is used in the metal form. PMID:26721786

  1. Possible organisms similar to Ediacaran forms from the Bhander Group, Vindhyan Supergroup, Late Neoproterozoic of India

    Science.gov (United States)

    De, Chirananda

    2003-01-01

    Fossil Medusoid genera resembling Ediacaria ( Sprigg 1947) and Hiemalora ( Fedonkin 1982) and having distinctive Ediacaran affinity have been discovered in a shale horizon occurring at the base of the Bhander Group, the uppermost unit of the Vindhyan Supergroup of central India. This is the first record of unequivocal occurrence of Ediacara-like fossils in a Proterozoic basin of the Peninsular India. This finding substantially extends the previously known biogeographic range of the Ediacaran elements to Peninsular India and further enhances their biostratigraphpic potential for correlation of the upper Vindhyans with some Ediacaran horizons of Canada, Australia, South Africa and Russian Platforms. With this extension, the representatives of the genus Ediacaria can be regarded as having a global distribution in places now occupying both lower and higher latitudes. The genus Hiemalora, which appeared to be endemic to the Russian block, also has wide biogeographic coverage. These fossils assign an Ediacaran (550-543 Ma) age for the host Lakheri Limestone and suggest that the Lakheri unit was deposited within 6 million years of the Precambrian-Cambrian boundary. They also support and refine the traditional view of the Late Neoproterozoic age for the lower Bhander Group. These fossils provide positive stratigraphic clues for locating the Precambiran-Cambrian boundary strata in the overlying Lakheri-Sirbu segment of the Vindhyan sequence. They also indicate a depositional environment typical of a muddy shallow shelf setting above storm wave-base.

  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. Sequential Linker Installation: Precise Placement of Functional Groups in Multivariate Metal-Organic Frameworks

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, S; Lu, WG; Chen, YP; Zhang, Q; Liu, TF; Feng, DW; Wang, X; Qin, JS; Zhou, HC

    2015-03-11

    A unique strategy, sequential linker installation (SLI), has been developed to construct multivariate MOFs with functional groups precisely positioned. PCN-700, a Zr-MOF with eight-connected Zr6O4(OH)(8)(H2O)(4) clusters, has been judiciously designed; the Zr-6 clusters in this MOF are arranged in such a fashion that, by replacement of terminal OH-/H2O ligands, subsequent insertion of linear dicarboxylate linkers is achieved. We demonstrate that linkers with distinct lengths and functionalities can be sequentially installed into PCN-700. Single-crystal to single-crystal transformation is realized so that the positions of the subsequently installed linkers are pinpointed via single-crystal X-ray diffraction analyses. This methodology provides a powerful tool to construct multivariate MOFs with precisely positioned functionalities in the desired proximity, which would otherwise be difficult to achieve.

  6. Self-categorization, affective commitment and group self-esteem as distinct aspects of social identity in the organization.

    Science.gov (United States)

    Bergami, M; Bagozzi, R P

    2000-12-01

    The purpose of this study is to distinguish between cognitive, affective and evaluative components of social identity in the organization and to show how the components instigate behaviours that benefit in-group members. A new scale for measuring cognitive organizational identification (i.e. self-categorization) is developed and compared to a leading scale. Internal consistency, convergent validity, predictive validity and generalizability of the two scales are established on a sample of Italian (N = 409) and Korean (N = 283) workers. Next, convergent and discriminant validity for measures of organizational identification, affective commitment and group self-esteem are demonstrated. Then, two antecedents of these components of social identity are examined: organization prestige and organization stereotypes. Finally, the mediating role of the components of social identity are investigated between the antecedents and five forms of citizenship behaviours. The last three analyses are performed on the Italian (N = 409) workers. Among other findings, the results show that affective commitment and self-esteem are the primary motivators of citizenship behaviours. Moreover, cognitive identification performs as a central mediator between prestige and stereotypes on the one hand, and affective commitment and self-esteem on the other. Identification is thus an indirect determinant of citizenship behaviours. PMID:11190685

  7. 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

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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.

  13. Astronomers Without Borders: An IYA2009 Organization Node Dedicated to Connecting Groups Worldwide

    Science.gov (United States)

    Simmons, Michael

    2008-05-01

    Astronomers Without Borders (AWB) is a new global organizational and IYA2009 Organizational Node dedicated to furthering understanding and goodwill across national and cultural boundaries using the universal appeal of astronomy, a common language spoken by all those who share an interest in the sky. It is a universal interest that connects us. The AWB network of Affiliates will bring together up to 1000 astronomy clubs, magazines and other organizations involved in astronomy. Regional Coordinators work within their own regions - based on common language and culture rather than political or geographic boundaries - to best implement AWB's goals, involve the region's participants and bring in new ideas based on local culture and tradition. Participation is free for all Affiliates. The AWB web site is the center for the network of Affiliates. This Community Center is the global meeting place where Affiliates interact. Forums, galleries and more interactive technologies will be used. Sharing Telescopes and Resources (STAR) gathers both surplus and new telescopes and other equipment in developed countries and donates them to clubs in undeveloped countries. Follow-up programs are meant to ensure the best and widest use of the telescope in the destination country, and to maintain a relationship between donors and recipients. The World at Night (TWAN) has been designated as a Special IYA2009 Project. TWAN's specialty photographers create wide-angle images of the night sky in important natural and historic settings around the world that dramatically demonstrate the universal nature and appeal of the night sky. A web site, major exhibitions and more are planned for IYA2009. Astro-tourism has been proposed by several Affiliates. This program will draw on existing facilities and experiences, primarily from the long-established solar eclipse tour industry. AWB is meant to continue and grow for many years beyond the end of IYA2009.

  14. 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.

  15. VEGETATIVE COMPATIBILITY GROUPS OF FUSARIUM OXYSPORUM, THE CAUSAL ORGANISM OF VASCULAR WILT ON ROSELLE IN MALAYSIA

    Directory of Open Access Journals (Sweden)

    K.H. Ooi

    1999-01-01

    Full Text Available Forty strains of Fusarium oxysporvm isolated from roselle (Hibiscus sabdariffa var. sabdariffa showing vascular wilt symptoms in three states (Terengganu, Penang and Ipoh in the northern Malaysian Peninsula were used to investigate the vegetative co mpatibility. Nitrate-nonutilizing (nil mutants were recovered from all the strains tested and subsequently used to study vegetative compatibility groups (VCG within the population by nit mutants pairings on minimal medium. Thirteen VCGs were found and none were vegetatively compatible with those of other formae speciales (f. spp. such as asparagi and cubense, and non-pathogenic strains from paddy and oil palm. The results indicate that there is substantial genetic diversity in F. oxysporum that causes vascular wilt disease on roselle as reflected by multiple VCGs, but the distribution of strains into the VCGs is not even as there are 26 representatives in VCG-1001M, two in VCG-1003M and VCG-1013M and only one in the other VCGs. This study may provide new insight into the establishment of a new forma specialis off. oxysporum.

  16. 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

  17. 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

  18. 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.

  19. 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...

  20. 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....

  1. 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. ...

  2. 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...

  3. 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...

  4. 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...

  5. 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: ...

  6. 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 ...

  7. 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.)

  8. 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.

  9. Surface Hydrophilicity and Functional Group-Driven Iron(III) Hydroxide Nucleation on Organic-Coated Substrates in Aqueous Environments

    Science.gov (United States)

    Ray, J.; Lee, B.; Baltrusaitis, J.; Jun, Y.

    2012-12-01

    polyaspartate substrate and least in the presence of the quartz substrate. Based on contact angle measurements and surface characterization, we concluded that the degree of hydrophilicity may control heterogeneous nucleation. Differences in substrate surface energy and potential arrangements of functional groups at the substrate surface (-OH and -COOH) may also contribute to the observed trends. These results provide new information for elucidating the effects of polymeric organic substrate coatings on the size, volume, and location of nucleating iron hydroxides, which will help predict nanoparticle interactions in natural and engineered systems. While iron oxide nanoparticles have been extensively studied in aqueous systems, there are still few studies providing in situ hetero- and homogeneous nucleation in the presence of relevant environmental organic substrates, which can aid in modeling the fate and transport of nanoparticles and contaminants in aqueous systems.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  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. Proton Inelastic Mean Free Path in a Group of Organic Materials in 0.05-10 MeV Range

    Institute of Scientific and Technical Information of China (English)

    TAN Zhen-Yu; XIA Yue-Yuan; ZHAO Ming-Wen; LIU Xiang-Dong

    2010-01-01

    @@ Inelastic mean free paths (MFPs) of 0.05-10 MeV protons in a group of 10 organic compounds are systematically calculated.The calculations are based on the method newly derived from the Ashley optical-data model and from the higher-order correction terms in stopping power calculations.Especially,in this method the new and empirical Bloch correction for the inelastic MFP is given.An evaluation for the optical energy loss function is incorporated into the present calculatious because of the lack of available experimental optical data for the considered organic compounds expect for kapton.The proton inelastic MFPs for these 10 organic compounds in the energy range from 0.05 to 10 Me V are presented here for the first time,and the combination of these inelastic MFP data and our previous data of stopping power calculation for these bioorganic compounds may form a useful database for Monte Carlo track-structure studies of various radiation effects on these materials.

  18. The T box regulatory element controlling expression of the class I lysyl-tRNA synthetase of Bacillus cereus strain 14579 is functional and can be partially induced by reduced charging of asparaginyl-tRNAAsn

    LENUS (Irish Health Repository)

    Foy, Niall

    2010-07-22

    Abstract Background Lysyl-tRNA synthetase (LysRS) is unique within the aminoacyl-tRNA synthetase family in that both class I (LysRS1) and class II (LysRS2) enzymes exist. LysRS1 enzymes are found in Archaebacteria and some eubacteria while all other organisms have LysRS2 enzymes. All sequenced strains of Bacillus cereus (except AH820) and Bacillus thuringiensis however encode both a class I and a class II LysRS. The lysK gene (encoding LysRS1) of B. cereus strain 14579 has an associated T box element, the first reported instance of potential T box control of LysRS expression. Results A global study of 891 completely sequenced bacterial genomes identified T box elements associated with control of LysRS expression in only four bacterial species: B. cereus, B. thuringiensis, Symbiobacterium thermophilum and Clostridium beijerinckii. Here we investigate the T box element found in the regulatory region of the lysK gene in B. cereus strain 14579. We show that this T box element is functional, responding in a canonical manner to an increased level of uncharged tRNALys but, unusually, also responding to an increased level of uncharged tRNAAsn. We also show that B. subtilis strains with T box regulated expression of the endogenous lysS or the heterologous lysK genes are viable. Conclusions The T box element controlling lysK (encoding LysRS1) expression in B. cereus strain 14579 is functional, but unusually responds to depletion of charged tRNALys and tRNAAsn. This may have the advantage of making LysRS1 expression responsive to a wider range of nutritional stresses. The viability of B. subtilis strains with a single LysRS1 or LysRS2, whose expression is controlled by this T box element, makes the rarity of the occurrence of such control of LysRS expression puzzling.

  19. The T box regulatory element controlling expression of the class I lysyl-tRNA synthetase of Bacillus cereus strain 14579 is functional and can be partially induced by reduced charging of asparaginyl-tRNAAsn

    Directory of Open Access Journals (Sweden)

    Conant Gavin C

    2010-07-01

    Full Text Available Abstract Background Lysyl-tRNA synthetase (LysRS is unique within the aminoacyl-tRNA synthetase family in that both class I (LysRS1 and class II (LysRS2 enzymes exist. LysRS1 enzymes are found in Archaebacteria and some eubacteria while all other organisms have LysRS2 enzymes. All sequenced strains of Bacillus cereus (except AH820 and Bacillus thuringiensis however encode both a class I and a class II LysRS. The lysK gene (encoding LysRS1 of B. cereus strain 14579 has an associated T box element, the first reported instance of potential T box control of LysRS expression. Results A global study of 891 completely sequenced bacterial genomes identified T box elements associated with control of LysRS expression in only four bacterial species: B. cereus, B. thuringiensis, Symbiobacterium thermophilum and Clostridium beijerinckii. Here we investigate the T box element found in the regulatory region of the lysK gene in B. cereus strain 14579. We show that this T box element is functional, responding in a canonical manner to an increased level of uncharged tRNALys but, unusually, also responding to an increased level of uncharged tRNAAsn. We also show that B. subtilis strains with T box regulated expression of the endogenous lysS or the heterologous lysK genes are viable. Conclusions The T box element controlling lysK (encoding LysRS1 expression in B. cereus strain 14579 is functional, but unusually responds to depletion of charged tRNALys and tRNAAsn. This may have the advantage of making LysRS1 expression responsive to a wider range of nutritional stresses. The viability of B. subtilis strains with a single LysRS1 or LysRS2, whose expression is controlled by this T box element, makes the rarity of the occurrence of such control of LysRS expression puzzling.

  20. Functional group analysis by H NMR/chemical derivatization for the characterization of organic aerosol from the SMOCC field campaign

    Directory of Open Access Journals (Sweden)

    E. Tagliavini

    2006-01-01

    Full Text Available Water soluble organic compounds (WSOC in aerosol samples collected in the Amazon Basin in a period encompassing the middle/late dry season and the beginning of the wet season, were investigated by H NMR spectroscopy. HiVol filter samples (PM2.5 and PM>2.5 and size-segregated samples from multistage impactor were subjected to H NMR characterization. The H NMR methodology, recently developed for the analysis of organic aerosol samples, has been improved by exploiting chemical methylation of carboxylic groups with diazomethane, which allows the direct determination of the carboxylic acid content of WSOC. The content of carboxylic carbons for the different periods and sizes ranged from 12% to 20% of total measured carbon depending on the season and aerosol size, with higher contents for the fine particles in the transition and wet periods with respect to the dry period. A comprehensive picture is presented of WSOC functional groups in aerosol samples representative of the biomass burning period, as well as of transition and semi-clean atmospheric conditions. A difference in composition between fine (PM2.5 and coarse (PM>2.5 size fractions emerged from the NMR data, the former showing higher alkylic content, the latter being largely dominated by R-O-H (or R-O-R' functional groups. Very small particles (<0.14 μm, however, present higher alkyl-chain content and less oxygenated carbons than larger fine particles (0.42–1.2 μm. More limited variations were found between the average compositions in the different periods of the campaign.

  1. Getting evidence into practice: the work of the Cochrane Effective Practice and Organization of care Group (EPOC).

    Science.gov (United States)

    Mowatt, G; Grimshaw, J M; Davis, D A; Mazmanian, P E

    2001-01-01

    Policy makers and continuing educators often face difficult decisions about which educational and quality assurance interventions to provide. Where possible, such decisions are best informed by rigorous evidence, such as that provided by systematic reviews. The Cochrane Collaboration is an international organization that aims to help people make well-informed decisions about health care by preparing, maintaining, and ensuring the accessibility of systematic reviews of the benefits and risks of health care interventions. International collaborative review groups prepare Cochrane reviews for publication in The Cochrane Library, a collection of databases available on CD-ROM and the World Wide Web and updated quarterly. The Cochrane Effective Practice and Organization of Care Group (EPOC) aims to prepare and maintain systematic reviews of professional, financial, organizational, and regulatory interventions that are designed to improve professional practice and the delivery of effective health services. EPOC has 17 reviews and 20 protocols published in Issue 3, 2000, of the Cochrane Library, with further protocols in development. We also have undertaken an overview of previously published systematic reviews of professional behavior change strategies. Our specialized register contains details of over 1,800 studies that fall within the group's scope. Systematic reviews provide a valuable source of information for policy makers and educators involved in planning continuing education and quality assurance initiatives and organizational change. EPOC will attempt to keep the Journal of Continuing Education in the Health Professions informed on an ongoing basis about new systematic reviews that it produces in the area of continuing medical education and quality assurance. PMID:11291587

  2. Effect of concentration of dispersed organic matter on optical maturity parameters: Interlaboratory results of the organic matter concentration working group of the ICCP.

    Science.gov (United States)

    Mendonca, Filho J.G.; Araujo, C.V.; Borrego, A.G.; Cook, A.; Flores, D.; Hackley, P.; Hower, J.C.; Kern, M.L.; Kommeren, K.; Kus, J.; Mastalerz, Maria; Mendonca, J.O.; Menezes, T.R.; Newman, J.; Ranasinghe, P.; Souza, I.V.A.F.; Suarez-Ruiz, I.; Ujiie, Y.

    2010-01-01

    The main objective of this work was to study the effect of the kerogen isolation procedures on maturity parameters of organic matter using optical microscopes. This work represents the results of the Organic Matter Concentration Working Group (OMCWG) of the International Committee for Coal and Organic Petrology (ICCP) during the years 2008 and 2009. Four samples have been analysed covering a range of maturity (low and moderate) and terrestrial and marine geological settings. The analyses comprise random vitrinite reflectance measured on both kerogen concentrate and whole rock mounts and fluorescence spectra taken on alginite. Eighteen participants from twelve laboratories from all over the world performed the analyses. Samples of continental settings contained enough vitrinite for participants to record around 50 measurements whereas fewer readings were taken on samples from marine setting. The scatter of results was also larger in the samples of marine origin. Similar vitrinite reflectance values were in general recorded in the whole rock and in the kerogen concentrate. The small deviations of the trend cannot be attributed to the acid treatment involved in kerogen isolation but to reasons related to components identification or to the difficulty to achieve a good polish of samples with high mineral matter content. In samples difficult to polish, vitrinite reflectance was measured on whole rock tended to be lower. The presence or absence of rock fabric affected the selection of the vitrinite population for measurement and this also had an influence in the average value reported and in the scatter of the results. Slightly lower standard deviations were reported for the analyses run on kerogen concentrates. Considering the spectral fluorescence results, it was observed that the ??max presents a shift to higher wavelengths in the kerogen concentrate sample in comparison to the whole-rock sample, thus revealing an influence of preparation methods (acid treatment) on

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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.

  8. Danish Breast Cancer Cooperative Group--DBCG: History, organization, and status of scientific achievements at 30-year anniversary

    DEFF Research Database (Denmark)

    Blichert-Toft, M.; Christiansen, Peter; Mouridsen, H.T.

    2008-01-01

    between experts handling diagnostic work-up, surgery, radiotherapy, medical oncology, and basic research, and, further, complete registration of relevant clinical data in a national data base attached to DBCG. Data are processed by the Secretariat personnel composed of statisticians, data managers...... cancer incident cases are reported and registered in the national data base. Today, the data base includes approximately 80 000 incidents of primary breast cancer. Annually, the Secretariat receives roughly 1.5 million parameters to be entered into the data base. Over time DBCG has generated seven......DBCG (Danish Breast Cancer Cooperative Group) constitutes a multidisciplinary organization established in 1975 by the Danish Surgical Society. The purpose involves first and foremost a nation-wide standardization of breast cancer treatment based on novel therapeutic principles, collaboration...

  9. Organic synthesis in the Smith Group: a personal selection of a dozen lessons learned at the University of Pennsylvania.

    Science.gov (United States)

    Minbiole, Kevin P C

    2016-04-01

    The passionate study of the complex and ever-evolving discipline of organic synthesis over more than a four-decade span is certain to elucidate meaningful and significant lessons. Over this period, Amos B. Smith III, the Rhodes-Thompson Professor of Chemistry and Member of the Monell Chemical Senses Center at the University of Pennsylvania, has mentored well over 100 doctoral and masters students, more than 200 postdoctoral associates and numerous undergraduates, in addition to collaborating with a wide spectrum of internationally recognized scholars. His research interests, broadly stated, comprise complex molecule synthesis, the development of new, versatile and highly effective synthetic methods, bioorganic and medicinal chemistry, peptide mimicry chemistry and material science. Each area demands a high level of synthetic design and execution. United by a passion to unlock the secrets of organic synthesis, and perhaps of Nature itself, innumerable lessons have been, and continue to be, learned by the members of the Smith Group. This lead article in a Special Issue of the Journal of Antibiotics affords an opportunity to share some of those lessons learned, albeit a small selection of personal favorites. PMID:26932408

  10. 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

  11. 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

  12. Effects of Random Environment on a Self-Organized Critical System: Renormalization Group Analysis of a Continuous Model

    Science.gov (United States)

    Antonov, N. V.; Kakin, P. I.

    2016-02-01

    We study effects of the random fluid motion on a system in a self-organized critical state. The latter is described by the continuous stochastic model proposed by Hwa and Kardar [Phys. Rev. Lett. 62: 1813 (1989)]. The advecting velocity field is Gaussian, not correlated in time, with the pair correlation function of the form ∝ δ(t - t')/k⊥d-1+ξ , where k⊥ = |k⊥| and k⊥ is the component of the wave vector, perpendicular to a certain preferred direction - the d-dimensional generalization of the ensemble introduced by Avellaneda and Majda [Commun. Math. Phys. 131: 381 (1990)]. Using the field theoretic renormalization group we show that, depending on the relation between the exponent ξ and the spatial dimension d, the system reveals different types of large-scale, long-time scaling behaviour, associated with the three possible fixed points of the renormalization group equations. They correspond to ordinary diffusion, to passively advected scalar field (the nonlinearity of the Hwa-Kardar model is irrelevant) and to the "pure" Hwa-Kardar model (the advection is irrelevant). For the special case ξ = 2(4 - d)/3 both the nonlinearity and the advection are important. The corresponding critical exponents are found exactly for all these cases.

  13. Flume experiments on permeability and organic matter as related to the genesis of uranium deposits in the Beaufort Group

    International Nuclear Information System (INIS)

    The size, shape, and grade of uranium deposits in the Beaufort Group was controlled primarily by the distribution of plant debris and the permeability of the host sediments at the time of mineralization. A natural sand, similar to the mineralized sandstone, was studied under different hydrodynamic conditions in a flume to determine the causes of local variations in these two factors. Linguoid small ripples, sinuous dunes, and upper flow regime plane beds were formed under vertical accretion conditions. The concentration of organics was controlled by local flow patterns over the respective bedforms and was inversely related to the current velocity. The permeability of the sand was a direct exponential function of its grain size, but sorting and the presence of absence of lamination influenced the permeability of the coarse and fine fractions respectively. In all cases, the lowest permeability was recorded in the vertical direction across the laminae, whereas measurements in the horizontal plane, normal to the current, generally showed the highest permeability. The experimental results confirm certain field observations on the distribution of uranium in the Beaufort Group and provide insight into some of the underlying ore controls. 8 figs., 8 tabs., 13 refs

  14. 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...

  15. 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

  16. Functional Groups and Structural Insights of Water-Soluble Organic Carbon using Ultrahigh Resolution FT-ICR Tandem Mass Spectrometry

    Science.gov (United States)

    Mazzoleni, L. R.; Habib, D.; Zhao, Y.; Dalbec, M.; Samburova, V.; Hallar, G.; Zielinska, B.; Lowenthal, D.

    2013-12-01

    Water-soluble organic carbon (WSOC) is a complex mixture of thousands of organic compounds which may have significant influence on the climate-relevant properties of atmospheric aerosols. An improved understanding of the molecular composition of WSOC is needed to evaluate the effect of aerosol composition upon aerosol physical properties. Products of gas phase, aqueous phase and particle phase reactions contribute to pre-existing aerosol organic mass or nucleate new aerosol particles. Thus, ambient aerosols carry a complex array of WSOC components with variable chemical signatures depending upon its origin and aerosol life-cycle processes. In this work, ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was used to characterize aerosol WSOC collected during the summer of 2010 at the Storm Peak Laboratory (3210 m a.s.l.) near Steamboat Springs, CO. Approximately 4000 molecular formulas were assigned in the mass range of m/z 100-800 after negative-ion electrospray ionization. The observed trends indicate significant non-oxidative accretion reaction pathways for the formation of high molecular weight WSOC components closely associated with terpene ozonolysis secondary organic aerosol (SOA). The aerosol WSOC was further characterized using ultrahigh resolution tandem MS analysis with infrared multiphoton dissociation to determine the functional groups and structural properties of 1700 WSOC species up to m/z 600. Due to the complex nature of the WSOC, multiple precursor ions were simultaneously fragmented. The exact mass measurements of the precursor and product ions facilitated molecular formula assignments and matching of neutral losses. The most important neutral losses are CO2, H2O, CH3OH, HNO3, CH3NO3, SO3 and SO4. The presence and frequency of these losses indicate the type of functional groups contained in the precursor structures. Consistent with the acidic nature of WSOC compounds, the most frequently observed losses

  17. 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.

  18. 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

  19. 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.

  20. 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...

  1. 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

  2. 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...

  3. Perspectives on Organ Donation in the Context of Sociodemographic Data and Levels of Burn Out in a Group of Nurse

    OpenAIRE

    Aytaş, Özgür; Kartalcı, Şükrü; ÜNAL, Süheyla

    2011-01-01

    Aim: Today, the biggest problem of organ transplantation is that organ donation rates are very low. The belief and attitude of health workers can change organ donation rates, as they are referred to as the vital important in the information and instruction of the patients and their relatives for organ donation. The aim of this study is to examine how the sociodemographic data and level of burn out in nurses affected their thoughts on organ donation. Method: 201 nurses working in Inonu Uni...

  4. 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

  5. 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...

  6. 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

  7. Group Flow and Group Genius

    Science.gov (United States)

    Sawyer, Keith

    2015-01-01

    Keith Sawyer views the spontaneous collaboration of group creativity and improvisation actions as "group flow," which organizations can use to function at optimum levels. Sawyer establishes ideal conditions for group flow: group goals, close listening, complete concentration, being in control, blending egos, equal participation, knowing…

  8. A metaanalysis of perceptual organization in schizophrenia, schizotypy, and other high-risk groups based on variants of the Embedded Figures Task.

    Directory of Open Access Journals (Sweden)

    Kirsten Rebecca Panton

    2016-02-01

    Full Text Available Current research on perceptual organization in schizophrenia frequently employs shapes with regularly sampled contours (fragmented stimuli, in noise fields composed of similar elements, to elicit visual abnormalities. However, perceptual organization is multi-factorial and, in earlier studies, continuous contours have also been employed in tasks assessing the ability to extract shapes from a background. We conducted a systematic review and meta-analysis of studies using closed-contour stimuli, including the Embedded Figures Test (EFT and related tasks, both in people with schizophrenia and in healthy schizotypes and relatives, considered at increased risk for psychosis. Eleven studies met the selection criteria for inclusion in the meta-analysis, including six that used a between-groups study design (i.e. perceptual organization abilities of schizophrenia/high-risk groups were compared to healthy or clinical controls, and five that treated schizophrenia symptoms or schizotypy traits and indices of perceptual organization as continuous variables. Effect sizes and heterogeneity statistics were calculated, and the risk of publication bias was explored. A significant, moderate effect for EFT performance was found with studies that compared performance of schizophrenia/high-risk groups to a healthy or patient comparison group (d = -.523, p<.001. However, significant heterogeneity was also found amongst the schizotypy, but not schizophrenia studies, as well as studies using accuracy, but not reaction time as a measure of performance. A non-significant correlation was found for the studies that examined schizophrenia symptoms or schizotypy traits as continuous variables (r = .012, p = .825. These results suggest that deficits in perceptual organization of non-fragmented stimuli are found when differences between schizophrenia/high-risk groups and comparison groups are maximized. These findings should motivate further investigation of perceptual

  9. A Metaanalysis of Perceptual Organization in Schizophrenia, Schizotypy, and Other High-Risk Groups Based on Variants of the Embedded Figures Task.

    Science.gov (United States)

    Panton, Kirsten R; Badcock, David R; Badcock, Johanna C

    2016-01-01

    Current research on perceptual organization in schizophrenia frequently employs shapes with regularly sampled contours (fragmented stimuli), in noise fields composed of similar elements, to elicit visual abnormalities. However, perceptual organization is multi-factorial and, in earlier studies, continuous contours have also been employed in tasks assessing the ability to extract shapes from a background. We conducted a systematic review and meta-analysis of studies using closed-contour stimuli, including the Embedded Figures Test (EFT) and related tasks, both in people with schizophrenia and in healthy schizotypes and relatives, considered at increased risk for psychosis. Eleven studies met the selection criteria for inclusion in the meta-analysis, including six that used a between-groups study design (i.e., perceptual organization abilities of schizophrenia/high-risk groups were compared to healthy or clinical controls), and five that treated schizophrenia symptoms or schizotypy traits and indices of perceptual organization as continuous variables. Effect sizes and heterogeneity statistics were calculated, and the risk of publication bias was explored. A significant, moderate effect for EFT performance was found with studies that compared performance of schizophrenia/high-risk groups to a healthy or patient comparison group (d = -0.523, p schizotypy, but not schizophrenia studies, as well as studies using accuracy, but not reaction time as a measure of performance. A non-significant correlation was found for the studies that examined schizophrenia symptoms or schizotypy traits as continuous variables (r = 0.012, p = 0.825). These results suggest that deficits in perceptual organization of non-fragmented stimuli are found when differences between schizophrenia/high-risk groups and comparison groups are maximized. These findings should motivate further investigation of perceptual organization abilities with closed-contour stimuli both in schizophrenia and high

  10. 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.

  11. 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

  12. 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

  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. Card Sorting as Collaborative Method for User-Driven Information Organizing on a Website: Recommendations for Running Collaborative Group Card Sorts in Practice

    Directory of Open Access Journals (Sweden)

    Maria Friis Bjerre

    2015-05-01

    Full Text Available Card sorting is an easy-to-use, quick, inexpensive, yet powerful usability method for information organizing on a website as it generates usable input directly from end-users as to how they would expect to find information on a website. When run collaboratively in groups, the discussion between the users about the content of the cards and their relatedness provides valuable insight into the users’ mental models. Focusing on epistemic asymmetry in the group discussion, this article highlights important issues which may affect the outcome of group card sorting. It is demonstrated that group card sorting demands great attention from the test manager in relation to the composition of the group, i.e. the number of users per group and the users’ educational level and formal organizational positions, in order to ensure a result that is representative of the group as a whole.

  16. Strengthen the collaboration between the River Basin Management Organization of China and International Environmental Specimen Bank Group.

    Science.gov (United States)

    Tan, Lingzhi; Liu, Hui; Shu, Jinxiang; Xia, Fan

    2015-02-01

    Several types of emerging organic contaminants were investigated in many recent researches, such as persistent toxic substance (PTS), persistent organic pollutants (POPs), endocrine disrupters (EDs), and volatile organic compounds (VOCs). But the Chinese country standard detection methods of emerging organic pollutants were not developed with the dramatic increasing of the organic substances production. Hence, it is necessary to obtain the latest informations about the long-term storage of representative environmental specimens, which could provide scientific basis for environmental management and environmental decision-making of the water resources protection and management organization. As the significant water resource conservation organization, the Water Environment Monitoring Center of Yangtze River Basin is experienced in water environmental monitoring and records many useful water resources and environment informations. It is also our responsibility to monitor all the pollutants in water environment of the Yangtze River valley, especially the emerging organic contaminants. Meanwhile, the International Environmental Specimen Bank (IESB) accumulates lots environmental organic pollution specimens and plays a significant role in environmental monitoring. Thus, the collaboration between the two parties will be greatly helpful for each further researches and monitoring work of organic contaminants in Yangtze River Basin. PMID:24817678

  17. 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.

  18. 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.

  19. 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...

  20. 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.

  1. 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

  2. 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

  3. 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...

  4. 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.

  5. 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.

  6. 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.

  7. Organizations

    DEFF Research Database (Denmark)

    Hatch, Mary Jo

    Most of us recognize that organizations are everywhere. You meet them on every street corner in the form of families and shops, study in them, work for them, buy from them, pay taxes to them. But have you given much thought to where they came from, what they are today, and what they might become in...... considers many more. Mary Jo Hatch introduces the concept of organizations by presenting definitions and ideas drawn from the a variety of subject areas including the physical sciences, economics, sociology, psychology, anthropology, literature, and the visual and performing arts. Drawing on examples from...... prehistory and everyday life, from the animal kingdom as well as from business, government, and other formal organizations, Hatch provides a lively and thought provoking introduction to the process of organization....

  8. 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

  9. Market access, organic farming and productivity: the effects of Fair Trade addiliation on Thai farmer producers groups

    OpenAIRE

    Becchetti, Leonardo; Conzo, Pierluigi; Gianfreda, Giuseppina

    2012-01-01

    The study analyses the impact of Fair Trade (FT) and organic farming on a sample of FT rice producers in Thailand. It finds that per capita income from agriculture is positively and significantly affected by years of organic certification and FT affiliation. The estimated FT and organic certification contributions to producers’ economic well-being are higher when account is taken of the relatively higher proportion of selfconsumption among affiliated farmers. But the per capita income effect ...

  10. 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...

  11. 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.)

  12. 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

  13. 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.

  14. 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

  15. 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

  16. The Redwood Coast Tsunami Work Group: a unique organization promoting earthquake and tsunami resilience on California's North Coast

    Science.gov (United States)

    Dengler, L.; Henderson, C.; Larkin, D.; Nicolini, T.; Ozaki, V.

    2012-12-01

    The Northern California counties of Del Norte, Humboldt, and Mendocino account for over 30% of California's coastline and is one of the most seismically active areas of the contiguous 48 states. The region is at risk from earthquakes located on- and offshore and from tsunamis generated locally from faults associated with the Cascadia subduction zone (CSZ) and from distant sources elsewhere in the Pacific. In 1995 the California Geological Survey (CGS) published a scenario for a CSZ earthquake that included both strong ground shaking effects and a tsunami. As a result of the scenario, the Redwood Coast Tsunami Work Group (RCTWG), an organization of government agencies, tribes, service groups, academia and the private sector, was formed to coordinate and promote earthquake and tsunami hazard awareness and mitigation in the three-county region. The RCTWG and its member agencies projects include education/outreach products and programs, tsunami hazard mapping, signage and siren planning. Since 2008, RCTWG has worked with the California Emergency Management Agency (Cal EMA) in conducting tsunami warning communications tests on the North Coast. In 2007, RCTWG members helped develop and carry out the first tsunami training exercise at FEMA's Emergency Management Institute in Emmitsburg, MD. The RCTWG has facilitated numerous multi-agency, multi-discipline coordinated exercises, and RCTWG county tsunami response plans have been a model for other regions of the state and country. Eight North Coast communities have been recognized as TsunamiReady by the National Weather Service, including the first National Park the first State Park and only tribe in California to be so recognized. Over 500 tsunami hazard zone signs have been posted in the RCTWG region since 2008. Eight assessment surveys from 1993 to 2010 have tracked preparedness actions and personal awareness of earthquake and tsunami hazards in the county and additional surveys have tracked public awareness and tourist

  17. Results obtained in the intercomparison of dosimetry systems Total body organized by In 2012, the European Group for radiation dosimetry (EURADOS) has organized an intercomparison of systems

    International Nuclear Information System (INIS)

    dosimetric full-length for photons, within the action on harmonization of the monitoring Individual of the radiation Externalestablished by the group. 88 dosimetric systems, 75 30 institutions have participated in the intercomparison countries. Each participant has sent a group of 26 dosimeters which have been irradiated with various doses and radiation qualities. The overall results of the intercomparison were presented recently (1). This communication presents the results obtained by our Center. EURADOS (IC2012). (Author)

  18. Characterizing Communication Networks in a Web-Based Classroom: Cognitive Styles and Linguistic Behavior of Self-Organizing Groups in Online Discussions

    Science.gov (United States)

    Vercellone-Smith, Pamela; Jablokow, Kathryn; Friedel, Curtis

    2012-01-01

    In this study, we explore the cognitive style profiles and linguistic patterns of self-organizing groups within a web-based graduate education course to determine how cognitive preferences and individual behaviors influence the patterns of information exchange and the formation of communication hierarchies in an online classroom. Network analysis…

  19. Workshop on Electron-Cloud Simulations for Proton and Positron Beams (ECLOUD'02) organized by the SL Accelerator Physics Group at CERN.

    CERN Multimedia

    Patrice Loïez

    2002-01-01

    This workshop was organized by the SL Accelerator Physics group at CERN from 15 to 18 April 2002. More than 60 participants from 17 institutes reflect the great worldwide interest in the electron-cloud phenomenon, which presently limits the performance of several storage rings and has become a concern for the LHC.

  20. Organic functional groups in aerosol particles from burning and non-burning forest emissions at a high-elevation mountain site

    Science.gov (United States)

    Takahama, S.; Schwartz, R. E.; Russell, L. M.; MacDonald, A. M.; Sharma, S.; Leaitch, W. R.

    2011-07-01

    Ambient particles collected on teflon filters at the Peak of Whistler Mountain, British Columbia (2182 m a.s.l.) during spring and summer 2009 were measured by Fourier transform infrared (FTIR) spectroscopy for organic functional groups (OFG). The project mean and standard deviation of organic aerosol mass concentrations (OM) for all samples was 3.2±3.3 (μg m-3). Measurements of aerosol mass fragments, size, and number concentrations were used to separate fossil-fuel combustion and burning and non-burning forest sources of the measured organic aerosol. The OM was composed of the same anthropogenic and non-burning forest components observed at Whistler mid-valley in the spring of 2008; during the 2009 campaign, biomass burning aerosol was additionally observed from fire episodes occurring between June and September. On average, organic hydroxyl, alkane, carboxylic acid, ketone, and primary amine groups represented 31 %±11 %, 34 %±9 %, 23 %±6 %, 6 %±7 %, and 6 %±3 % of OM, respectively. Ketones in aerosols were associated with burning and non-burning forest origins, and represented up to 27 % of the OM. The organic aerosol fraction resided almost entirely in the submicron fraction without significant diurnal variations. OM/OC mass ratios ranged mostly between 2.0 and 2.2 and O/C atomic ratios between 0.57 and 0.76, indicating that the organic aerosol reaching the site was highly aged and possibly formed through secondary formation processes.