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Sample records for thuringiensis serovar sotto

  1. Cloning of the Bacillus thuringiensis serovar sotto chitinase (Schi gene and characterization of its protein

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    Wan-Fang Zhong

    2005-12-01

    Full Text Available Chitinase plays a positive role in the pathogenicity of Bacillus thuringiensis to insect pests. We used touchdown PCR to clone the chitinase (Schi gene from Bacillus thuringiensis serovar sotto (Bt sotto chromosomal DNA. Our DNA sequencing analysis revealed that the Bt sotto Schi gene consists of an open reading frame (ORF of 2067 nucleotides with codes for the chitinase precursor. We also found that the putative promoter consensus sequences (the -35 and -10 regions of the Bt soto Schi gene are identical to those of the chiA71 gene from Bt Pakistani, the chiA74 gene from Bt kenyae and the ichi gene from Bt israelensis. The Schi chitinase precursor is 688 amino acids long with an estimated molecular mass of 75.75 kDa and a theoretical isoelectric point of 5.74, and contains four domains, which are, in sequence, a signal peptide, an N-terminal catalytic domain, a fibronectin type III like domain and a C-terminal chitin-binding domain. Sequence comparison and the evolutionary relationship of the Bt sotto Schi chitinase to other chitinase and chitinase-like proteins are also discussed.

  2. The complete genome sequence of Bacillus thuringiensis serovar Hailuosis YWC2-8.

    Science.gov (United States)

    Zhu, Jun; Zhang, Qinbin; Cao, Ye; Li, Qiao; Zhu, Zizhong; Wang, Linxia; Li, Ping

    2016-02-10

    Bacillus thuringiensis, a typical aerobic, Gram-positive, spore-forming bacterium, is an important microbial insecticide widely used in the control of agricultural pests. B. thuringiensis serovar Hailuosis YWC2-8 with high insecticidal activity against Diptera and Lepidoptera insects has three insecticidal crystal protein genes, such as cry4Cb2, cry30Ea2, and cry56Aa1. In this study, the complete genome sequence of B. thuringiensis YWC2-8 was analyzed, which contains one circular gapless chromosome and six circular plasmids. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Solubilization, Activation, and Insecticidal Activity of Bacillus thuringiensis Serovar thompsoni HD542 Crystal Proteins

    NARCIS (Netherlands)

    Naimov, S.; Boncheva, R.; Karlova, R.B.; Dukiandjiev, S.; Minkov, I.; Maagd, de R.A.

    2008-01-01

    Cry15Aa protein, produced by Bacillus thuringiensis serovar thompsoni HD542 in a crystal together with a 40 kDa accompanying protein is one of a small group of non-typical, less well-studied members of the Cry family of insecticidal proteins, and may provide an alternative for the more commonly used

  4. Multilocus sequence analysis of Bacillus thuringiensis serovars navarrensis, bolivia and vazensis and Bacillus weihenstephanensis reveals a common phylogeny.

    Science.gov (United States)

    Soufiane, Brahim; Baizet, Mathilde; Côté, Jean-Charles

    2013-01-01

    The Bacillus cereus group sensu lato includes six closely-related bacterial species: Bacillus cereus, Bacillus anthracis, Bacillus thuringiensis, Bacillus mycoides, Bacillus pseudomycoides and Bacillus weihenstephanensis. B. thuringiensis is distinguished from the other species mainly by the appearance of an inclusion body upon sporulation. B. weihenstephanensis is distinguished based on its psychrotolerance and the presence of specific signature sequences in the 16S rRNA gene and cspA genes. A total of seven housekeeping genes (glpF, gmK, ilvD, pta, purH, pycA and tpi) from different B. thuringiensis serovars and B. weihenstephanensis strains were amplified and their nucleotide sequences determined. A maximum likelihood phylogenetic tree was inferred from comparisons of the concatenated sequences. B. thuringiensis serovars navarrensis, bolivia and vazensis clustered not with the other B. thuringiensis serovars but rather with the B. weihenstephanensis strains, indicative of a common phylogeny. In addition, specific signature sequences and single nucleotide polymorphisms common to B. thuringiensis serovars navarrensis, bolivia and vazensis and the B. weihenstephanensis strains, and absent in the other B. thuringiensis serovars, were identified.

  5. Expression of Bacillus thuringiensis serovar. israelensis toxins in Asticcacaulis excentricus to control dipteran larvae of vectors of diseases

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    Óscar Enrique Guevara

    2004-01-01

    Full Text Available Bacillus thuringiensis cry genes encode for a diverse group of crystal-forming proteins that exhibit insecticidal activity towards dipteran, lepidopteran and coleopteran larvae. The effectiveness of insecticides based on mosquito larvicidal B. thuringiensis strains can be enhanced by using aquatic prosthecated bacteria as alternative hosts, since they do not sink, cytoplasmic located toxins are protected f rom UV radiation and, most importantly, mosquito larvae feed on them. An Asticcacaulis excentricus reference strain was transformed with the cry1 1Aa gene from Bacillus thuringiensis serovar. israelensis. Western blot and electrophoresis were used to test recombinant protein expression; Western blot revealed a 72 kDa protein corresponding to B. thuringiensis serovar. israelensis Cry1 1 Aa. These aquatic bacte­rias toxicity achieved 50% mortality at 23 ng/mL concentration in f irst instar Culex quinquefasciatus larvae. Other bioassays indicated that recombinant A. excentricus is toxic against Aedes aegyptiand Anopheles albimanus first instar larvae. Buoyancy tests demonstrated the advantage of A. excentricus over B. thuringiensis. Key words: Asticcacaulis excentricus, Bacillus thuringiensis, prosthecated bacteria, dengue, malaria.

  6. Low persistence of Bacillus thuringiensis serovar israelensis spores in four mosquito biotopes of a salt marsh in southern France.

    Science.gov (United States)

    Hajaij, Myriam; Carron, Alexandre; Deleuze, Julien; Gaven, Bruno; Setier-Rio, Marie-Laure; Vigo, Gerard; Thiéry, Isabelle; Nielsen-LeRoux, Christina; Lagneau, Christophe

    2005-11-01

    We studied the persistence of Bacillus thuringiensis serovar israelensis (Bti) in a typical breeding site of the mosquito Ochlerotatus caspius in a particularly sensitive salt marsh ecosystem following two Bti-based larvicidal applications (Vectobac 12AS, 1.95 L/ha). The treated area was composed of four larval biotopes that differed in terms of the most representative plant species (Sarcocornia fruticosa, Bolboschoenus maritimus, Phragmites australis, and Juncus maritimus) and the physical and chemical characteristics of the soil. We sampled water, soil, and plants at various times before and after the applications (from spring to autumn, 2001) and quantified the spores of B. thuringiensis (Bt) and Bacillus species. The B. cereus group accounted for between 0% and 20% of all Bacillus spp. before application depending on the larval biotope. No Bti were found before application. The variation in the quantity of bacilli during the mosquito breeding season depended more on the larval biotope than on the season or the larvicidal application. More bacilli were found in soil (10(4)-10(6) spores/g) than on plant samples (10(2)-10(4) spores/g). The abundance in water (10(5) to 10(7) spores/L) appeared to be correlated to the water level of the breeding site. The number of Bti spores increased just after application, after declining; no spores were detected in soil or water 3 months after application. However, low numbers of Bti spores were present on foliage from three of the four studied plant strata. In conclusion, the larvicidal application has very little impact on Bacillus spp. flora after one breeding season (two applications).

  7. Histopathological and ultrastructural effects of delta-endotoxins of Bacillus thuringiensis serovar israelensis in the midgut of Simulium pertinax larvae (Diptera, Simuliidae

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    CFG Cavados

    2004-08-01

    Full Text Available The bacterium Bacillus thuringiensis (Bt produces parasporal crystals containing delta-endotoxins responsible for selective insecticidal activity on larvae. Upon ingestion, these crystals are solubilized in the midgut lumen and converted into active toxins that bind to receptors present on the microvilli causing serious damage to the epithelial columnar cells. We investigated the effect of these endotoxins on larvae of the Simulium pertinax, a common black fly in Brazil, using several concentrations during 4 h of the serovar israelensis strain IPS-82 (LFB-FIOCRUZ 584, serotype H-14 type strain of the Institute Pasteur, Paris. Light and electron microscope observations revealed, by time and endotoxin concentration, increasing damages of the larvae midgut epithelium. The most characteristic effects were midgut columnar cell vacuolization, microvilli damages, epithelium cell contents passing into the midgut lumen and finally the cell death. This article is the first report of the histopathological effects of the Bti endotoxins in the midgut of S. pertinax larvae and the data obtained may contribute to a better understanding of the mode of action of this bacterial strain used as bioinsecticide against black fly larvae.

  8. Larval gut pH profile in pestiferous .i.Chironomus crassicaudatus./i. and .i.Glyptotendipes paripes./i. (Chironomidae: Diptera) in reference to the toxicity potential of .i.Bacillus thuringiensis./i. serovar .i.israelensis./i

    Czech Academy of Sciences Publication Activity Database

    Frouz, Jan; Lobinske, R.J.; Yaqub, A.; Ali, A.

    2007-01-01

    Roč. 23, č. 3 (2007), s. 355-358 ISSN 8756-971X Institutional research plan: CEZ:AV0Z60660521 Keywords : chironomidae larvae * gut pH * Bacillus thuringiensis serovar israelensis Subject RIV: EH - Ecology, Behaviour Impact factor: 0.706, year: 2007

  9. Histopathology of Anticarsia gemmatalis Hübner (Lepidoptera; Noctuidae treated with Nucleopolyhedrovirus and Bacillus thuringiensis serovar kurstaki Histopatologia de Anticarsia gemmatalis Hübner (Lepidoptera; Noctuidae tratadas com Virus de Poliedrose Nuclear e Bacillus thuringiensis sorovar kurstaki

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    Neiva Knaak

    2005-06-01

    Full Text Available The Anticarsia gemmatalis is responsible for the use of chemical insecticides in the soybean culture, causing a significant increase in the costs of farming and a great unbalance in the ecosystem. The use of microbial agents, like Bacillus thuringiensis serovar kurstaki (Btk and Anticarsia gemmatalis nucleopolyhedrovirus (AgNPV, they are an alternative to chemical control of the pest insects. In the interaction analysis of the entomopathogenic bacteria and virus it is considered important the in vitro action mode of these microbiology control agents. Therefore, the present study aims the histopathological analysis of the A. gemmatalis larvae digestive system after the interaction in vivo of the entomopathogenic Btk and AgNPV, represented the Dipel and Baculovirus anticarsia formulations, respectively. The evaluations were realized in larvae of 2nd instar, in which the mortality was evaluated daily, and a histopathology was done with collected larvae in time of 1, 3, 6, 12 and 24 hours after the treatments application. The results of the in vivo assays reveal that the treatment using the association of AgNPV-Btk (98.68% of mortality was more efficient than using AgNPV isolatedly (81.28% of mortality, but the Btk when used isolatedly had a mortality of 100%. The treatments showed significant (PA Anticarsia gemmatalis é responsável pelo uso de inseticidas químicos na cultura da soja, ocasionando um significativo aumento nos custos das lavouras e um grande desequilíbrio no ecossistema. O uso de agentes microbianos, como Bacillus thuringiensis sorovar kurstaki (Btk e Vírus de Poliedrose Nuclear de Anticarsia gemmatalis (VPNAg, é uma alternativa para o controle químico de insetos-praga. Na análise da interação de bactérias e vírus entomopatogênicos, considera-se importante o modo de ação in vitro desses agentes de controle microbiano. Assim, o presente trabalho objetiva a análise histopatológica do sistema digestivo das lagartas de A

  10. LC and LD50 values of Bacillus thuringiensis Serovar japonensis strain buibui toxin to Oriental beetle and northern masked chafer larvae (Coleoptera: Scarabaeidae).

    Science.gov (United States)

    Mashtoly, Tamer A; El-Zemaity, Mohamed El-Said; Hussien, Mohamed I; Alm, Steven R

    2009-10-01

    Bacillus thuringiensis serovar japonensis strain Buibui has the potential to be an important control agent for pest scarabs. Bioassays were designed to test B. t. japonensis against two of the major turf and ornamental scarab pests infesting turfgrasses and ornamentals and to serve as a basis for further tests against other scarab pests. LC and LD50 values of B. t. serovarjaponensis strain Buibui toxin and spores were determined by four different bioassays for the oriental beetle, Anomala orientalis (Waterhouse), and northern masked chafer, Cyclocephala borealis Arrow. Oriental beetle larvae were bioassayed in autoclaved and nonautoclaved soil from where they were collected (Kingston, RI [native]), in nonautoclaved soil from where the northern masked chafer larvae were collected (Groton, CT [foreign]), and per os. Northern masked chafer larvae were bioassayed in autoclaved and nonautoclaved soil from where they were collected (Groton, CT [native]), in nonautoclaved soil from where the oriental beetle larvae were collected (Kingston, RI [foreign]) and per os. LC50 values of 3.93 microg toxin/g autoclaved native soil, 1.80 microg toxin/g nonautoclaved native soil, and 0.42 microg toxin/g nonautoclaved foreign soil and an LD50 value of 0.41 microg per os were determined at 14 d forA. orientalis. LC50 values of 588.28 microg toxin/g autoclaved native soil, 155.10 microg toxin/g nonautoclaved native soil, 265.32 microg toxin/g nonautoclaved foreign soil, and LD50 of 5.21 microg per os were determined at 14 d (soils) and 10 d (per os) for C. borealis. There were significant differences in LC50 values for oriental beetles in autoclaved, nonautoclaved native soil and nonautoclaved foreign soil. There were significant differences in LCo values for northern masked chafers in autoclaved and nonautoclaved native soil. B. t. japonensis can be applied now for control of oriental beetles at rates that are economically competitive with synthetic chemicals. If we can determine the

  11. Evaluation of the impact of Bacillus thuringiensis serovar israelensis and Temephos, used for the control of Simulium (Chirostilbia pertinax Kollar, 1832 (Diptera, Simuliidae on the associated entomofauna, Paraty, state of Rio de Janeiro, Brazil

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    Araújo-Coutinho Carlos José Pereira da Cunha de

    2003-01-01

    Full Text Available The study was set up to evaluate the impact of two commercial larvicide formulations, Bacillus thuringiensis serovar israelensis base (Bti at 15 ppm/1 min and temephos at 0.03 ppm of active ingredient, used to control Simulium pertinax populations, on associated non-target entomofauna occupying the same breeding sites. The experiments were carried out on the Pedra Branca and Muricana rivers, on the slopes of Serra do Mar massif, municipality of Paraty, state of Rio de Janeiro, Brazil. Bti was applied to the river Pedra Branca and temephosto theriver Muricana. On both rivers, treatment and control sections were labeled as such, each one with two observation posts: slow moving water and fast water regions respectively. Artificial substrata was used to evaluate the abundance of associated entomofauna. Attached immature stages of arthropods were removed from both of its surfaces fortnightly. Were collected, from the two rivers, 28 477 specimens of the entomofauna associated with S. pertinax. The families Hydropsychidae, Chironomidae, Bactidae, Simuliidae, Blephariceridae and Megapodagrionidae were represented. These was an impact of temephos on the entomofauna associated with S. pertinax only in Simuliidae and Chironomidae, and to Bti only in Simuliidae. However, the reduction in their numbers was not statistically significant.

  12. Expresión de la toxina Cry11Aa de Bacillus thuringiensis serovar. israelensis en Asticcacaulis excentricus, para el control de larvas acuáticas de dípteros de la familia Culicidae, vectores de enfermedades Expression of Bacillus thuringiensis serovar. israelensis toxins in Asticcacaulis excentricus to control dipteran larvae of vectors of diseases

    OpenAIRE

    Orduz Sergio; Guevara Óscar Enrique; Armengol Gemma; Crickmore Neil

    2004-01-01

    Los genes cry de Bacillus thuringiensis codifican para un diverso grupo de proteínas formadoras de cristales que exhiben actividad insecticida contra larvas de dípteros, lepidópteros y coleópteros, entre otros. La efectividad de los insecticidas basados en formulaciones de proteínas de B. thuringiensis puede ser mejorada usando bacterias prostecadas acuáticas como portadoras alternativas de los genes cry, ya que no se sedimentan rápidamente; las proteínas expresadas en el citoplasma están pro...

  13. Expresión de la toxina cry11aa de bacillus thuringiensis serovar. israelensis en asticcacaulis excentricus, para el control de larvas acuáticas de dípteros de la familia culicidae, vectores de enfermedades

    OpenAIRE

    Guevara, Óscar Enrique; Armengol, Gemma; Crickmore, Neil; Orduz, Sergio

    2007-01-01

    Los genes cry de Bacillus thuringiensis codifican para un diverso grupo de proteínas formadoras de cristales que exhiben actividad insecticida contra larvas de dípteros, lepidópteros y coleópteros, entre otros. La efectividad de los insecticidas basados en formulaciones de proteínas de B. thuringiensis puede ser mejorada usando bacterias prostecadas acuáticas como portadoras alternativas de los genes cry, ya que no se sedimentan rápidamente; las proteínas expresadas en el citoplasma están pro...

  14. Sotto Voce: Exploring the Interplay of Conversation and Mobile Audio Spaces

    OpenAIRE

    Aoki, Paul M.; Grinter, Rebecca E.; Hurst, Amy; Szymanski, Margaret H.; Thornton, James D.; Woodruff, Allison

    2002-01-01

    In addition to providing information to individual visitors, electronic guidebooks have the potential to facilitate social interaction between visitors and their companions. However, many systems impede visitor interaction. By contrast, our electronic guidebook, Sotto Voce, has social interaction as a primary design goal. The system enables visitors to share audio information - specifically, they can hear each other's guidebook activity using a technologically mediated audio eavesdropping mec...

  15. Bacillus thuringiensis

    Science.gov (United States)

    Hollensteiner, Jacqueline; Wemheuer, Franziska; Harting, Rebekka; Kolarzyk, Anna M; Diaz Valerio, Stefani M; Poehlein, Anja; Brzuszkiewicz, Elzbieta B; Nesemann, Kai; Braus-Stromeyer, Susanna A; Braus, Gerhard H; Daniel, Rolf; Liesegang, Heiko

    2016-01-01

    Verticillium wilt causes severe yield losses in a broad range of economically important crops worldwide. As many soil fumigants have a severe environmental impact, new biocontrol strategies are needed. Members of the genus Bacillus are known as plant growth-promoting bacteria (PGPB) as well as biocontrol agents of pests and diseases. In this study, we isolated 267 Bacillus strains from root-associated soil of field-grown tomato plants. We evaluated the antifungal potential of 20 phenotypically diverse strains according to their antagonistic activity against the two phytopathogenic fungi Verticillium dahliae and Verticillium longisporum . In addition, the 20 strains were sequenced and phylogenetically characterized by multi-locus sequence typing (MLST) resulting in 7 different Bacillus thuringiensis and 13 Bacillus weihenstephanensis strains. All B. thuringiensis isolates inhibited in vitro the tomato pathogen V. dahliae JR2, but had only low efficacy against the tomato-foreign pathogen V. longisporum 43. All B. weihenstephanensis isolates exhibited no fungicidal activity whereas three B. weihenstephanensis isolates showed antagonistic effects on both phytopathogens. These strains had a rhizoid colony morphology, which has not been described for B. weihenstephanensis strains previously. Genome analysis of all isolates revealed putative genes encoding fungicidal substances and resulted in identification of 304 secondary metabolite gene clusters including 101 non-ribosomal polypeptide synthetases and 203 ribosomal-synthesized and post-translationally modified peptides. All genomes encoded genes for the synthesis of the antifungal siderophore bacillibactin. In the genome of one B. thuringiensis strain, a gene cluster for zwittermicin A was detected. Isolates which either exhibited an inhibitory or an interfering effect on the growth of the phytopathogens carried one or two genes encoding putative mycolitic chitinases, which might contribute to antifungal activities

  16. Bacillus thuringiensis dendrolimus T84A1の殺虫性蛋白質遺伝子の塩基配列の決定

    OpenAIRE

    Ogo, Masashi; Yamada, Shoichi; Kobayashi, Yasuo; Shibata, Jiro; Nagamatsu, Yasunori

    1990-01-01

    A 3882 nucleotides sequence including the complete crystal protein gene of Bacillus thuringiensis (B. t.) dendrolimus T84A1 was determined by the dideoxy-chain termination method. It was revealed that the gene of B. t. dendrolimus is highly homologous to that of B. t. sotto (SHIBANO et al., 1986). According to the suggested nomenclature, this gene is classified into cryIA(a) (HOFTE and WHITELEY, 1989). The open reading frame encoded. a 133487.71 Da protein consisting of 1180 amino acid residu...

  17. Plasmid patterns of efficient and inefficient strains of Bacillus thuringiensis against Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Fagundes, R B S; Picoli, E A T; Lana, U G P; Valicente, Fernando H

    2011-10-01

    Bacillus thuringiensis harbors genes encoding Cry proteins found in chromosomes or plasmids of different sizes (4-150 Mb). Although the smaller plasmids are more abundant in B. thuringiensis, their specific function is unknown. As for the megaplasmids, their main recognized function is to harbor cry genes, although the sequencing of some of these plasmids indicates the occurrence of other important genes. This work used a new protocol for practical and rapid extraction of plasmid DNA in order to characterize the plasmid patterns of Brazilian strains belonging to Embrapa Milho e Sorgo research center B. thuringiensis bank. We tried to further assess the relationship of plasmid patterns with strains belonging to the same serovars and strains causing 100% and no mortality to Spodoptera frugiperda (J.E. Smith) larvae. It was possible to characterize 59 strains based on the migration of bands in agarose gel. Strains belonging to the same serovars showed different plasmid sizes (from 1,636 bp to 23,200 bp), with the exception of two strains belonging to serovar galleriae. The strain T09 Bt tolworthi showed a plasmid migration pattern identical to strains belonging to serovar galleriae. Plasmid patterns differed for 46 strains, confirming that this is a useful tool to discriminate specific strains. However, it was not possible to associate the plasmid pattern or the occurrence of particular plasmids with the pathogenicity of a given species towards S. frugiperda larvae.

  18. Bacillus thuringiensis (Bt)

    Science.gov (United States)

    2004-01-01

    Bacillus thuringiensis (Bt), a natural bacteria found all over the Earth, has a fairly novel way of getting rid of unwanted insects. Bt forms a protein substance (shown on the right) that is not harmful to humans, birds, fish or other vertebrates. When eaten by insect larvae the protein causes a fatal loss of appetite. For over 25 years agricultural chemical companies have relied heavily upon safe Bt pesticides. New space based research promises to give the insecticide a new dimension in effectiveness and applicability. Researchers from the Consortium for Materials Development in Space along with industrial affiliates such as Abott Labs and Pern State University flew Bt on a Space Shuttle mission in the fall of 1996. Researchers expect that the Shuttle's microgravity environment will reveal new information about the protein that will make it more effective against a wider variety of pests.

  19. Efficient transformation of Bacillus thuringiensis requires nonmethylated plasmid DNA.

    OpenAIRE

    Macaluso, A; Mettus, A M

    1991-01-01

    The transformation efficiency of Bacillus thuringiensis depends upon the source of plasmid DNA. DNA isolated from B. thuringiensis, Bacillus megaterium, or a Dam- Dcm- Escherichia coli strain efficiently transformed several B. thuringiensis strains, B. thuringiensis strains were grouped according to which B. thuringiensis backgrounds were suitable sources of DNA for transformation of other B. thuringiensis strains, suggesting that B. thuringiensis strains differ in DNA modification and restri...

  20. 76 FR 14289 - Bacillus thuringiensis

    Science.gov (United States)

    2011-03-16

    ... a plant- incorporated protectant in accordance with the terms of Experimental Use Permit (EUP) No... chemistry data for eCry3.1Ab were required for a human health effects assessment. Even so, preliminary... EPA granting registrations or experimental use permits of Bacillus thuringiensis-based pesticides or...

  1. Salmonella serovars differentially stimulate bovine leukocyte responses in vitro

    Science.gov (United States)

    The majority of Salmonella serovars cause no clinical signs in cattle, while some serovars, such as Salmonella enterica serovar Typhimurium (ST) and Dublin (SD), may cause severe disease. Mechanisms underlying the difference in pathogenesis between different serovars are not clear. The objective of ...

  2. Synergistic activity of Bacillus thuringiensis toxins against Simulium spp. larvae.

    Science.gov (United States)

    Monnerat, Rose; Pereira, Eleny; Teles, Beatriz; Martins, Erica; Praça, Lilian; Queiroz, Paulo; Soberon, Mario; Bravo, Alejandra; Ramos, Felipe; Soares, Carlos Marcelo

    2014-09-01

    Species of Simulium spread diseases in humans and animals such as onchocerciasis and mansonelosis, causing health problems and economic loses. One alternative for controlling these insects is the use of Bacillus thuringiensis serovar israelensis (Bti). This bacterium produces different dipteran-active Cry and Cyt toxins and has been widely used in blackfly biological control programs worldwide. Studies on other insect targets have revealed the role of individual Cry and Cyt proteins in toxicity and demonstrated a synergistic effect among them. However, the insecticidal activity and interactions of these proteins against Simulium larvae have not been reported. In this study we demonstrate that Cry4Ba is the most effective toxin followed by Cry4Aa and Cry11Aa. Cry10Aa and Cyt1Aa were not toxic when administered alone but both were able to synergise the activity of Cry4B and Cry11Aa toxins. Cyt1Aa is also able to synergise with Cry4Aa. The mixture of all toxin-producing strains showed the greatest level of synergism, but still lower than the Bti parental strain. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Characterization of Isolates of Salmonella enterica Serovar Stanley, a Serovar Endemic to Asia and Associated with Travel

    DEFF Research Database (Denmark)

    Hendriksen, Rene S.; Le Hello, Simon; Bortolaia, Valeria

    2012-01-01

    Salmonella enterica serovar Stanley (S. Stanley) is a common serovar in Southeast Asia and was the second most common serovar implicated in human salmonellosis in Thailand in the years 2002 to 2007. In contrast, this serovar is relatively uncommon in Europe. The objective of this study was to cha...

  4. Occurrence of Bacillus thuringiensis in faeces of herbivorous farm ...

    African Journals Online (AJOL)

    Bacillus thuringiensis (Berliner), the insect pathogen has been isolated from a variety of habitat. It is understood that the habitat of B. thuringiensis has always been associated with their biological activity. In the present study, B. thuringiensis was isolated from faeces of cows and goats. The phenotypic characterization ...

  5. Serovars of Salmonella from captive reptiles

    DEFF Research Database (Denmark)

    Pedersen, Karl; Lassen-Nielsen, Anne Marie; Nordentoft, Steen

    2009-01-01

    The distribution on serovars of 60 Salmonella isolates from reptiles kept in captivity in Denmark during the period 1995–2006 was investigated. The isolates were all recovered from clinical specimens submitted to the National Veterinary Institute. A majority of the samples were from reptiles...... in zoological gardens or similar, while a minor number was from reptiles kept in private homes. A total of 43 serovars were detected, most of them being what is usually called exotic serotypes, and many not having a trivial name, while a few isolates belonged to well-known human pathogenic serovars, such as S....... Enteritidis, S. Typhimurium, S. Bovismorbificans. One isolate was rough and two were non-typeable. Isolates from turtles belonged to the subspecies enterica, while many isolates from both sauria and snakes belonged to other subspecies. The findings underline the potential zoonotic risk by handling reptiles...

  6. Serovars of Mycobacterium avium Complex isolated from patients in Denmark

    DEFF Research Database (Denmark)

    Askgaard, D. S.; Giese, Steen Bjørck; Thybo, S.

    1994-01-01

    Danish isolates of Mycobacterium avium complex were serotyped by the use of seroagglutination. The most prevalent serovars among patients with AIDS (n = 89) were 4 and 6, while among non-AIDS patients the most prevalent serovars were 1, 6, and 4, with no major differences between those in patients...... with pulmonary disease (n = 65) and those in patients with lymph node infection (n = 58). The results suggest a Scandinavian distribution of serovars with a predominance of serovar 6 and fail to demonstrate any selective protection against different serovars by Mycobacterium bovis ECG vaccination....

  7. BOOK REVIEW – BACILLUS THURINGIENSIS: A CORNERSTONE OF MODERN AGRICULTURE BACILLUS THURINGIENSIS

    Science.gov (United States)

    Are you interested in the technical issues surrounding the use of Bacillus thuringiensis pesticidal traits as sprays and as plant incorporated protectants (transgenic crops)? Should the dimensions of human health, ecology, entomology, risk assessment, resistance management, and d...

  8. Quinolone resistance in Salmonella enterica serovar Typhi ...

    African Journals Online (AJOL)

    Introduction. The human restricted bacteria, Salmonella enterica serovar. Typhi is the major cause of typhoid fever (or enteric fever), a characteristic severe systemic illness [1]. In 2010, typhoid fever accounted for an estimated global burden of. 27 million new cases and 200,000 deaths [2]. For over two decades, S. enterica ...

  9. Transferrin Impacts Bacillus thuringiensis Biofilm Levels

    Directory of Open Access Journals (Sweden)

    Bianca Garner

    2016-01-01

    Full Text Available The present study examined the impact of transferrin on Bacillus thuringiensis biofilms. Three commercial strains, an environmental strain (33679, the type strain (10792, and an isolate from a diseased insect (700872, were cultured in iron restricted minimal medium. All strains produced biofilm when grown in vinyl plates at 30°C. B. thuringiensis 33679 had a biofilm biomass more than twice the concentration exhibited by the other strains. The addition of transferrin resulted in slightly increased growth yields for 2 of the 3 strains tested, including 33679. In contrast, the addition of 50 μg/mL of transferrin resulted in an 80% decrease in biofilm levels for strain 33679. When the growth temperature was increased to 37°C, the addition of 50 μg/mL of transferrin increased culture turbidity for only strain 33679. Biofilm levels were again decreased in strain 33679 at 37°C. Growth of B. thuringiensis cultures in polystyrene resulted in a decrease in overall growth yields at 30°C, with biofilm levels significantly decreased for 33679 in the presence of transferrin. These findings demonstrate that transferrin impacts biofilm formation in select strains of B. thuringiensis. Identification of these differences in biofilm regulation may be beneficial in elucidating potential virulence mechanisms among the differing strains.

  10. Preliminary investigations reveal that Bacillus thuringiensis δ ...

    African Journals Online (AJOL)

    The imminent introduction of transgenic crops into Kenya requires a rigorous assessment of the potential risks involved. This study focused on the possible effect of Bacillus thuringiensisδ-endotoxin [CryIA(c)] on arbuscular mycorrhizal fungi (AMF) associated with sorghum. In green house experiments, sorghum seedlings ...

  11. Isolation and characterization of native Bacillus thuringiensis ...

    African Journals Online (AJOL)

    ... (<30% mortality) or non insecticidal activity. However, results of motility, hemolytic activity, antibiotic-susceptibility patterns, and crystal shape, seem to suggest that many of our Bt isolates may exhibit parasporins activity. Key words: Bacillus thuringiensis, parasporal crystal, isolation, biochemical type, insecticidal, cry gene, ...

  12. Purification And Characterization Of Marine Bacillus Thuringiensis ...

    African Journals Online (AJOL)

    Urease was purified to homogeneity from Bacillus thuringiensis N2 using different purification steps namely, 55% acetone precipitation, DEAE-Sephadex A50 anion exchange column and Sephadex G120-200 gel filtration chromatography. The enzyme was purified 95.27 fold and showed a final specific activity of 10.48 ...

  13. Bacillus thuringiensis and its application in agriculture

    African Journals Online (AJOL)

    USER

    2010-04-05

    Apr 5, 2010 ... Presently, a number of approaches to pest control via genetic engineering have been developed and genetically engineered crops ... of this bacterium, which are effective against Lepidop-. *Corresponding author. E-mail: .... provide a useful tool for management of resistance to B. thuringiensis toxins ...

  14. BACILLUS THURINGIENSIS ELASTASES WITH INSECTICIDE ACTIVITY

    Directory of Open Access Journals (Sweden)

    E. V. Matseliukh

    2015-10-01

    Full Text Available The purpose of the research was a screening of proteases with elastase activity among Bacillus thuringiensis strains, their isolation, partially purification, study of physicochemical properties and insecticide activity in relation to the larvae of the Colorado beetle. The objects of the investigation were 18 strains of B. thuringiensis, isolated from different sources: sea water, dry biological product "Bitoksibatsillin" and also from natural populations of Colorado beetles of the Crimea, Kherson, Odesa, Mykolaiv and Zaporizhiia regions of Ukraine. Purification of enzymes with elastase activity isolated from above mentioned strains was performed by gel-chromatography and insecticide activity was studied on the 3–4 larvae instar of Colorado beetle. The ability of a number of B. thuringiensis strains to synthesize the proteases with elastase activity has been established. The most active were enzymes obtained from strains IMV B-7465, IMV B-7324 isolated from sea water, and strains 9, 902, Bt-H and 0-239 isolated from Colorado beetles. The study of the physicochemical properties of the partially purified proteases of these strains showed that they belonged to enzymes of the serine type. Peptidases of a number of B. thuringiensis strains (IMV B-7324, IMV B-7465, 902, 0-239, 9 are metal-dependent enzymes. Optimal conditions of action of all tested enzymes are the neutral and alkaline рН values and the temperatures of 30–40 °С. The studies of influence of the complex enzyme preparations and partially purified ones of B. thuringiensis strains on the larvae instar of Colorado beetles indicated that enzymes with elastase activity could be responsible for insecticide action of the tested strains.

  15. Salmonella enterica: Survival, Colonization, and Virulence Differences among Serovars

    Science.gov (United States)

    Andino, A.; Hanning, I.

    2015-01-01

    Data indicate that prevalence of specific serovars of Salmonella enterica in human foodborne illness is not correlated with their prevalence in feed. Given that feed is a suboptimal environment for S. enterica, it appears that survival in poultry feed may be an independent factor unrelated to virulence of specific serovars of Salmonella. Additionally, S. enterica serovars appear to have different host specificity and the ability to cause disease in those hosts is also serovar dependent. These differences among the serovars may be related to gene presence or absence and expression levels of those genes. With a better understanding of serovar specificity, mitigation methods can be implemented to control Salmonella at preharvest and postharvest levels. PMID:25664339

  16. Isolation of bacillus thuringiensis from different samples from Mansehra District

    International Nuclear Information System (INIS)

    Younis, F.; Lodhi, A.F.; Raza, G.

    2009-01-01

    The insecticidal activity of Bacillus thuringiensis has made it very interesting for the control of a variety of agricultural pests and human disease vectors. The present study is an attempt to explore the potential and diversity. of Bacillus thuringiensis. from the local environment for the control of cotton spotted bollworm (Earias sp.), a major pest of cotton. Two hundred and ninety eight samples of soil, grain dust, wild animal dung, birds dropping, decaying leaves and dead insects were collected from different ecological environments of Mansehra District yielding 438 Bacillus thuringiensis isolates that produce parasporal crystalline inclusions. In this study the soil samples were found to be the richest source for Bacillus thuringiensis. (author)

  17. Isolation and Characterization of Bacillus thuringiensis strains from ...

    African Journals Online (AJOL)

    Twelve isolates of Bacillus thuringiensis were obtained from soil samples collected from farmers' fields in Kakamega and Machakos districts. Soil samples from Machakos yielded more B. thuringiensis isolates t han those from Kakamega. Three isolates K13-1, 12F-K and K10-2 were obtained from Kakamega soil samples.

  18. Isolation and characterization of Bacillus thuringiensis from soils in ...

    African Journals Online (AJOL)

    Of 110 Bacillus thuringiensis isolates analyzed for the presence of crystal protein genes, 7 tested positive for cry 4, cry 11, and cyt toxin genes. Sequencing of these genes in positive strains demonstrated 99–100 % homology to known mosquitocidal cry and cyt genes in Bacillus thuringiensis subsp. israelensis. The present ...

  19. Characterization of Bacillus thuringiensis strains from Jordan and ...

    African Journals Online (AJOL)

    Eight serotypes with Bacillus thuringiensis israelensis being the most common. Out of the twenty-six isolated strains, five strains (serotype: kenyae, kurstaki, kurstaki HD1 and thuringiensis) that produced bipyramid crystal proteins were toxic to the lepidoptera larvae of Ephestia kuehniella Zeller. The SDS-PAGE protein ...

  20. Ecology and diversity of Bacillus thuringiensis in soil environment ...

    African Journals Online (AJOL)

    Bacillus thuringiensis populations ranged between 4.23 x 105, 6.52 x 105 cfu/g soil and consist of 11 types of isolates with 3 polymorphic, 7 spherical and 1 bipyramidal type of crystals. Polymorphic crystal containing isolates were further characterized. B. thuringiensis isolates were circular, white, flat and undulate or entire.

  1. by lipase from Bacillus thuringiensis and Lysinibacillus sphaericus

    African Journals Online (AJOL)

    This study reported production of lipase by Bacillus thuringiensis and Lysinibacillus sphaericus. Bacteria isolates were screened on Bushnell-Hass Mineral Salt medium containing 1% PMS for oil degradation. Two potent isolates were identified using 16S rRNA as Bacillus thuringiensis and Lysinibacillus sphaericus.

  2. Arginine-dependent acid resistance in Salmonella enterica serovar Typhimurium

    NARCIS (Netherlands)

    Kieboom, J.; Abee, T.

    2006-01-01

    Salmonella enterica serovar Typhimurium does not survive a pH 2.5 acid challenge under conditions similar to those used for Escherichia coli (J. W. Foster, Nat. Rev. Microbiol. 2:898-907, 2004). Here, we provide evidence that S. enterica serovar Typhimurium can display arginine-dependent acid

  3. Transcriptional response of turkeys to MDR Salmonella enterica serovar heidelberg

    Science.gov (United States)

    Food-producing animals such as swine, cattle and poultry are a major reservoir of the human foodborne pathogen Salmonella. While some Salmonella serovars can cause disease in food-producing animals, most serovars colonize these animals asymptomatically, resulting in the hosts becoming carriers and ...

  4. Pattern of multi-drug resistant Salmonella enterica serovar typhi ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-11-05

    Nov 5, 2008 ... Typhoid fever continues to remain a health problem as the causative organism, Salmonella enterica serovar typhi, has developed resistance to many antibiotics used. This study was undertaken to determine the current pattern of resistance to antimicrobial agents by S. enterica serovar typhi isolates.

  5. Chlamydia trachomatis serovar distributions in Russian men and women: a comparison with Dutch serovar distributions

    NARCIS (Netherlands)

    Smelov, V.; Quint, K. D.; Pleijster, J.; Savelkoul, P. H. M.; Shalepo, K.; Shipitsyna, E.; Domeika, M.; Gorelov, A.; Savicheva, A.; Quint, W. G. V.; de Vries, H. J. C.; Ouburg, S.; Morré, S. A.

    2009-01-01

    The data on serovar distributions of Chlamydia trachomatis - the most diagnosed sexually transmitted infection (STI) worldwide - are important for epidemiologic purposes and transmission studies but are completely lacking in Russia. The aim of the current study is to determine the serogroup and

  6. Ecological aspects of Bacillus thuringiensis in an Oxisol Ecologia do Bacillus thuringiensis num Latossolo

    Directory of Open Access Journals (Sweden)

    Lessandra Heck Paes Leme Ferreira

    2003-02-01

    Full Text Available Bacillus thuringiensis is a Gram positive, sporangial bacterium, known for its insecticidal habilities. Survival and conjugation ability of B. thuringiensis strains were investigated; vegetative cells were evaluated in non-sterile soil. Vegetative cells decreased rapidly in number, and after 48 hours the population was predominantly spores. No plasmid transfer was observed in non-sterile soil, probably because the cells died and the remaining cells sporulated quickly. Soil is not a favorable environment for B. thuringiensis multiplication and conjugation. The fate of purified B. thuringiensis toxin was analyzed by extractable toxin quantification using ELISA. The extractable toxin probably declined due to binding on surface-active particles in the soil.O comportamento de células vegetativas do Bacillus thuringiensis foi estudado em solo não esterilizado. Após o inóculo grande parte das células morrem e o restante esporula em 24 horas. Não foi observada conjugação provavelmente porque poucas células sobrevivem no solo e rapidamente esporulam, mostrando que este não é o ambiente propício para a multiplicação e conjugação desta bactéria. A toxina purificada, portanto livre de células, diminui rapidamente sua quantidade em solo não esterilizado. Provavelmente a ligação da toxina na fração argilosa do solo é a principal responsável por este fenômeno.

  7. Plasmid-associated sensitivity of Bacillus thuringiensis to UV light

    International Nuclear Information System (INIS)

    Benoit, T.G.; Wilson, G.R.; Bull, D.L.; Aronson, A.I.

    1990-01-01

    Spores and vegetative cells of Bacillus thuringiensis were more sensitive to UV light than were spores or cells of plasmid-cured B. thuringiensis strains or of the closely related Bacillus cereus. Introduction of B. thuringiensis plasmids into B. cereus by cell mating increased the UV sensitivity of the cells and spores. Protoxins encoded by one or more B. thuringiensis plasmids were not involved in spore sensitivity, since a B. thuringiensis strain conditional for protoxin accumulation was equally sensitive at the permissive and nonpermissive temperatures. In addition, introduction of either a cloned protoxin gene, the cloning vector, or another plasmid not containing a protoxin gene into a plasmid-cured strain of B. thuringiensis all increased the UV sensitivity of the spores. Although the variety of small, acid-soluble proteins was the same in the spores of all strains examined, the quantity of dipicolinic acid was about twice as high in the plasmid-containing strains, and this may account for the differences in UV sensitivity of the spores. The cells of some strains harboring only B. thuringiensis plasmids were much more sensitive than cells of any of the other strains, and the differences were much greater than observed with spores

  8. Colicinogeny in Salmonella serovars isolated in Brazil

    Directory of Open Access Journals (Sweden)

    Leila Carvalho Campos

    1988-06-01

    Full Text Available A study of colicinogeny was made in 748 strains of Salmonella (97 serovars isolated from different sources; human (291, animal (119, environmental (141, food (102 and animal feed (95. Colicin production was detected in 64 strains (8.6%, particularly isolated from foods (30.4%. Col. E1 (53 and Ia (44 were the most frequently observed, especially in S. agona for environment and food sources. Col V production was identified in 5 strains of S. typhimurium within 8 producer cultures isolated from humans. Its relationship with the sources and serovars of Salmonella are discussed.Investigou-se a produção de colicina em 748 amostras de Salmonella (97 sorovares advindas de díferentes fontes: humana (291, animal (119, ambiental (141, de alimentos (102 e rações (95. Detectaram-se 64 amostras (8,6% colicinogênicas, particularmente isoladas de alimentos (30,4%. ColE1 (53 e Ia (44 foram as mais freqüentes, especialmente no sorovar S, agona, de origem ambiental e de alimentos. Identificou-se também a produção de col V em 5 amostras de S. typhimurium dentre 8 culturas produtoras de origem humana. Discute-se a relação entre a capacidade colicinogênica e as fontes e sorovares de Salmonella.

  9. Ultra-violet-resistant mutants of Bacillus thuringiensis

    International Nuclear Information System (INIS)

    Jones, D.R.; Karunakaran, V.; Hacking, A.J.

    1991-01-01

    One of the main disadvantages of using Bacillus thuringiensis as an insecticide is that the spore and crystal preparations applied to foliage are readily washed away by rain and are inactivated by sunlight. Spores from some strains of B. thuringiensis have been shown to be highly sensitive to u.v. light. This study has demonstrated how mutants with increased resistance to u.v., isolated by successive rounds of u.v. irradiation, and additionally with increased specific pathogenicity can be isolated. These techniques should be applied to strains that are frequently used in the industrial production of B.thuringiensis toxin. (author)

  10. Bacillus thuringiensis Conjugation in Simulated Microgravity

    Science.gov (United States)

    Beuls, Elise; van Houdt, Rob; Leys, Natalie; Dijkstra, Camelia; Larkin, Oliver; Mahillon, Jacques

    2009-10-01

    Spaceflight experiments have suggested a possible effect of microgravity on the plasmid transfer among strains of the Gram-positive Bacillus thuringiensis, as opposed to no effect recorded for Gram-negative conjugation. To investigate these potential effects in a more affordable experimental setup, three ground-based microgravity simulators were tested: the Rotating Wall Vessel (RWV), the Random Positioning Machine (RPM), and a superconducting magnet. The bacterial conjugative system consisted in biparental matings between two B. thuringiensis strains, where the transfer frequencies of the conjugative plasmid pAW63 and its ability to mobilize the nonconjugative plasmid pUB110 were assessed. Specifically, potential plasmid transfers in a 0-g position (simulated microgravity) were compared to those obtained under 1-g (normal gravity) condition in each device. Statistical analyses revealed no significant difference in the conjugative and mobilizable transfer frequencies between the three different simulated microgravitational conditions and our standard laboratory condition. These important ground-based observations emphasize the fact that, though no stimulation of plasmid transfer was observed, no inhibition was observed either. In the case of Gram-positive bacteria, this ability to exchange plasmids in weightlessness, as occurs under Earth's conditions, should be seen as particularly relevant in the scope of spread of antibiotic resistances and bacterial virulence.

  11. BOOK REVIEW: BACILLUS THURINGIENSIS: A CORNERSTONE OF MODERN AGRICULTURE

    Science.gov (United States)

    Are you interested in the technical issues surrounding the use of Bacillus thuringiensis pesticidal traits as sprays and as plant incorporated protectants (transgenic crops)? Should the dimensions of human health, ecology, entomology, risk assessment, resistance management, and d...

  12. Cytotoxic effects of delfin insecticide ( Bacillus thuringiensis ) on cell ...

    African Journals Online (AJOL)

    Cytotoxic effects of delfin insecticide ( Bacillus thuringiensis ) on cell behaviour, phagocytosis, contractile vacuole activity and macronucleus in a protozoan ciliate Paramecium caudatum. ... macronucleus, fragmentation, vacuolization and complete diffusion of macronucleus were observed and were dose dependent.

  13. Cry1A(b)16 toxin from Bacillus thuringiensis: Theoretical refinement of three-dimensional structure and prediction of peptides as molecular markers for detection of genetically modified organisms.

    Science.gov (United States)

    Plácido, Alexandra; Coelho, Andreia; Abreu Nascimento, Lucas; Gomes Vasconcelos, Andreanne; Fátima Barroso, Maria; Ramos-Jesus, Joilson; Costa, Vladimir; das Chagas Alves Lima, Francisco; Delerue-Matos, Cristina; Martins Ramos, Ricardo; Marani, Mariela M; Roberto de Souza de Almeida Leite, José

    2017-07-01

    Transgenic maize produced by the insertion of the Cry transgene into its genome became the second most cultivated crop worldwide. Cry gene from Bacillus thuringiensis kurstaki expresses protein derivatives of crystalline endotoxins which confer insect resistance onto the maize crop. Mandatory labeling of processed food containing or made by genetically modified organisms is in force in many countries, so, it is very urgent to develop fast and practical methods for GMO identification, for example, biosensors. In the absence of an available empirical structure of Cry1A(b)16 protein, a theoretical model was effectively generated, in this work, by homology modeling and molecular dynamics simulations based on two available homologous protein structures. Molecular dynamics simulations were carried out to refine the selected model, and an analysis of its global structure was performed. The refined models of Cry1A(b)16 showed a standard fold and structural characteristics similar to those seen in Bacillus thuringiensis Cry1A(a) insecticidal toxin and Bacillus thuringiensis serovar kurstaki Cry1A(c) toxin. After in silico analysis of Cry1A(b)16, two immunoreactive candidate peptides were selected and specific polyclonal antibodies were produced resulting in antibody-peptide interaction. Biosensing devices are expected to be developed for detection of the Cry1A(b) protein as a marker of transgenic maize in food. Proteins 2017; 85:1248-1257. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  14. Six new leptospiral serovars isolated from wild animals in Peru.

    OpenAIRE

    Liceras de Hidalgo, J L; Sulzer, K R

    1984-01-01

    Six new serovars of Leptospira interrogans were isolated from opossums (Didelphis marsupialis and Philander opossum) trapped in the Peruvian jungle. The proposed names, type strain designation, and serogroup of the serovars, respectively, were: huallaga, strain M-7, Djasiman serogroup; luis, strain M-6, Tarassovi serogroup; machiguenga, strain MMD-3, Icterohaemorrhagiae serogroup; rioja, strain MR-12, Bataviae serogroup; rupa rupa, strain M-3, Sejroe serogroup; and tingomaria, strain M-13, Cy...

  15. Comparative genomics of extrachromosomal elements in Bacillus thuringiensis subsp. israelensis.

    Science.gov (United States)

    Bolotin, Alexandre; Gillis, Annika; Sanchis, Vincent; Nielsen-LeRoux, Christina; Mahillon, Jacques; Lereclus, Didier; Sorokin, Alexei

    2017-05-01

    Bacillus thuringiensis subsp. israelensis is one of the most important microorganisms used against mosquitoes. It was intensively studied following its discovery and became a model bacterium of the B. thuringiensis species. Those studies focused on toxin genes, aggregation-associated conjugation, linear genome phages, etc. Recent announcements of genomic sequences of different strains have not been explicitly related to the biological properties studied. We report data on plasmid content analysis of four strains using ultra-high-throughput sequencing. The strains were commercial product isolates, with their putative ancestor and type B. thuringiensis subsp. israelensis strain sequenced earlier. The assembled contigs corresponding to published and novel data were assigned to plasmids described earlier in B. thuringiensis subsp. israelensis and other B. thuringiensis strains. A new 360 kb plasmid was identified, encoding multiple transporters, also found in most of the earlier sequenced strains. Our genomic data show the presence of two toxin-coding plasmids of 128 and 100 kb instead of the reported 225 kb plasmid, a co-integrate of the former two. In two of the sequenced strains, only a 100 kb plasmid was present. Some heterogeneity exists in the small plasmid content and structure between strains. These data support the perception of active plasmid exchange among B. thuringiensis subsp. israelensis strains in nature. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  16. Camel as a transboundary vector for emerging exotic Salmonella serovars.

    Science.gov (United States)

    Ghoneim, Nahed H; Abdel-Moein, Khaled A; Zaher, Hala

    2017-05-01

    The current study was conducted to shed light on the role of imported camels as a transboundary vector for emerging exotic Salmonella serovars. Fecal samples were collected from 206 camels directly after slaughtering including 25 local camels and 181 imported ones as well as stool specimens were obtained from 50 slaughterhouse workers at the same abattoir. The obtained samples were cultured while Salmonella serovars were identified through Gram's stain films, biochemical tests and serotyping with antisera kit. Moreover, the obtained Salmonella serovars were examined by PCR for the presence of invA and stn genes. The overall prevalence of Salmonella serovars among the examined camels was 8.3%. Stn gene was detected in the vast majority of exotic strains (11/14) 78.6% including emerging serovars such as Salmonella Saintpaul, S. Chester, S. Typhimurium whereas only one isolate from local camels carried stn gene (1/3) 33.3%. On the other hand, none of the examined humans yielded positive result. Our findings highlight the potential role of imported camels as a transboundary vector for exotic emerging Salomenella serovars.

  17. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Science.gov (United States)

    2010-07-01

    ... thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement... killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens is exempt from the...

  18. Determination of Leptospira borgpetersenii serovar Javanica and Leptospira interrogans serovar Bataviae as the persistent Leptospira serovars circulating in the urban rat populations in Peninsular Malaysia.

    Science.gov (United States)

    Benacer, Douadi; Mohd Zain, Siti Nursheena; Sim, Shin Zhu; Mohd Khalid, Mohd Khairul Nizam; Galloway, Renee L; Souris, Marc; Thong, Kwai Lin

    2016-03-01

    Leptospirosis is an emerging infectious disease of global significance, and is endemic in tropical countries, including Malaysia. Over the last decade, a dramatic increase of human cases was reported; however, information on the primary vector, the rat, and the Leptospira serovars circulating among the rat population is limited. Therefore, the present study was undertaken to isolate Leptospira and characterise the serovars circulating in the urban rat populations from selected main cities in Peninsular Malaysia. Rat trappings were carried out between October 2011 to February 2014 in five urban cities which were chosen as study sites to represent different geographical locations in Peninsular Malaysia. Microscopic agglutination test (MAT) and PCR were carried out to identify the Leptospiral serogroup and determine the pathogenic status of the isolates, respectively while pulsed-field gel electrophoresis (PFGE) and random amplified polymorphic DNA (RAPD)-PCR were used to characterize the isolates. Three rat species were identified from the three hundred and fifty seven rats captured with Rattus rattus, being the dominant rat species (285, 80 %) followed by Rattus norgevicus (53, 15 %) and Rattus exulans (19, 5 %). Only 39 samples (11.0 %) were positive by culture and further confirmed as pathogenic Leptospira by PCR. Significant associations were shown between host infection with locality, season, host-age and species. Based on MAT, two serogroups were identified in the population namely; L. borgpetersenii serogroup Javanica (n = 16) and L. interrogans serogroup Bataviae (n = 23). Pulsed-field gel electrophoresis (PFGE) distinguished the two serovars in the urban rat populations: L. borgpetersenii serovar Javanica (41 %), and L. interrogans serovar Bataviae (59 %). RAPD-PCR yielded 14 distinct patterns and was found to be more discriminative than PFGE. This study confirms two Leptospira serovars circulating among the urban rats population in Peninsular

  19. SR450 and Superhawk XP Applications of Bacillus Thuringiensis Israelensis Against Culex Quinquefasciatus

    Science.gov (United States)

    2014-09-01

    SR450 AND SUPERHAWK XP APPLICATIONS OF BACILLUS THURINGIENSIS ISRAELENSIS AGAINST CULEX QUINQUEFASCIATUS1 JAMES C. DUNFORD,2 CRAIG A. STOOPS,3 ALDEN...thermal fogger applications of VectobacH WDG Bacillus thuringiensis israelensis (Bti) against Culex quinquefasciatus. Bacillus thuringiensis ...3. DATES COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE SR450 and Superhawk XP Applications of Bacillus Thuringiensis Israelensis

  20. Initial Study of Production of Bacillus thuringiensis israelensis Using Locally Obtained Substrates

    OpenAIRE

    Soesanto, Soesanto

    2015-01-01

    Bacillus thuringiensis israelensis diketahui sebagai entomopatogen nyamuk ades aegypti yang merupakan vektor penyakit demam berdarah.Telah dilakukan percobaan produksi Bacillus thuringiensis israelensis dengan menggunakan medium yang mengandung bahan lokal terasi udang, melase dan tepung kedelai. Hasil uji toksisitas (bioassay) terhadap Final Whole Culture (FWC) dengan bahan lokal yang murah menunjukkan potensi sebagai agensia bioinsektisida.Key Words: entomopathogen - Bacillus thuringiensis ...

  1. 40 CFR 180.1011 - Viable spores of the microorganism Bacillus thuringiensis Berliner; exemption from the...

    Science.gov (United States)

    2010-07-01

    ... Bacillus thuringiensis Berliner; exemption from the requirement of a tolerance. 180.1011 Section 180.1011... microorganism Bacillus thuringiensis Berliner; exemption from the requirement of a tolerance. (a) For the... authentic strain of Bacillus thuringiensis Berliner conforming to the morphological and biochemical...

  2. Complete genome sequence of Leptospira interrogans serovar Bratislava, strain PigK151

    Science.gov (United States)

    The genus Leptospira contains pathogens serologically classified into over 250 serovars, intermediate pathogens and saprophytes with genetic classification into 21 different species. Worldwide, leptospirosis is one of the most widespread zoonoses. L. interrogans serovar Bratislava has been isolated ...

  3. Complete genome sequence of Leptospira alstonii serovar room 22, strain GWTS#1

    Science.gov (United States)

    We report the complete genome sequence of Leptospira alstonii serovar room 22 strain GWTS#1. This is the first isolate of L. alstonii to be cultured from a mammal, in Western Europe, and represents a new serovar of pathogenic leptospires....

  4. Practical considerations on surveillance of Salmonella serovars other than Enteritidis and Typhimurium

    DEFF Research Database (Denmark)

    Wagenaar, J. A.; Hendriksen, Rene S.; Carrigue-Mas, J.

    2013-01-01

    Non-typhoid Salmonella serovars other than Salmonella enterica serovars S. Enteritidis (SE) and S. Typhimurium (ST) are isolated throughout the world with huge variations in prevalence. Besides the more generally occurring serovars, such as S. Infantis and S. Hadar, there are many examples of ser...

  5. The classification of Sejroe group serovars of Leptospira interrogans with monoclonal antibodies

    NARCIS (Netherlands)

    Terpstra, W. J.; Korver, H.; van Leeuwen, J.; Klatser, P. R.; Kolk, A. H.

    1985-01-01

    Using the hybridoma technique we produced monoclonal antibodies to serovars of Leptospira interrogans. We focussed on serovar hardjo which is an important pathogen for humans and animals, and on other serovars of the Sejroe group. With combinations of monoclonals, characteristic patterns of

  6. Photoprotection of Bacillus thuringiensis kurstaki from ultraviolet irradiation

    International Nuclear Information System (INIS)

    Cohen, E.; Rozen, H.; Joseph, T.; Braun, S.; Margulies, L.

    1991-01-01

    Irradiation of Bacillus thuringiensis var. kurstaki HD1 at 300-350 nm for up to 12 hr using a photochemical reactor results in a rapid loss of its toxicity to larvae of Heliothis armigera. Photoprotection of the toxic component was obtained by adsorption of cationic chromophores such as acriflavin (AF), methyl green, and rhodamine B to B. thuringiensis. AF gave the best photoprotection and a level of 0.42 mmol/g dye absorbed per gram of B. thuringiensis was highly toxic even after 12 hr of ultraviolet (uv) irradiation as compared to the control (77.5 and 5% of insect mortality, respectively). Ultraviolet and Fourier-transform infrared spectroscopic studies indicate molecular interactions between B. thuringiensis and AF. The nature of these interactions and energy or charge transfer as possible mechanisms of photoprotection are discussed. It is speculated that tryptophan residues are essential for the toxic effect of B. thuringiensis. It is suggested that photoprotection is attained as energy is transferred from the excited tryptophan moieties to the chromophore molecules

  7. SinR controls enterotoxin expression in Bacillus thuringiensis biofilms.

    Directory of Open Access Journals (Sweden)

    Annette Fagerlund

    Full Text Available The entomopathogen Bacillus thuringiensis produces dense biofilms under various conditions. Here, we report that the transition phase regulators Spo0A, AbrB and SinR control biofilm formation and swimming motility in B. thuringiensis, just as they control biofilm formation and swarming motility in the closely related saprophyte species B. subtilis. However, microarray analysis indicated that in B. thuringiensis, in contrast to B. subtilis, SinR does not control an eps operon involved in exopolysaccharides production, but regulates genes involved in the biosynthesis of the lipopeptide kurstakin. This lipopeptide is required for biofilm formation and was previously shown to be important for survival in the host cadaver (necrotrophism. Microarray analysis also revealed that the SinR regulon contains genes coding for the Hbl enterotoxin. Transcriptional fusion assays, Western blots and hemolysis assays confirmed that SinR controls Hbl expression, together with PlcR, the main virulence regulator in B. thuringiensis. We show that Hbl is expressed in a sustained way in a small subpopulation of the biofilm, whereas almost all the planktonic population transiently expresses Hbl. The gene coding for SinI, an antagonist of SinR, is expressed in the same biofilm subpopulation as hbl, suggesting that hbl transcription heterogeneity is SinI-dependent. B. thuringiensis and B. cereus are enteric bacteria which possibly form biofilms lining the host intestinal epithelium. Toxins produced in biofilms could therefore be delivered directly to the target tissue.

  8. Genome features of Leptospira interrogans serovar Copenhageni

    Directory of Open Access Journals (Sweden)

    A.L.T.O. Nascimento

    2004-04-01

    Full Text Available We report novel features of the genome sequence of Leptospira interrogans serovar Copenhageni, a highly invasive spirochete. Leptospira species colonize a significant proportion of rodent populations worldwide and produce life-threatening infections in mammals. Genomic sequence analysis reveals the presence of a competent transport system with 13 families of genes encoding for major transporters including a three-member component efflux system compatible with the long-term survival of this organism. The leptospiral genome contains a broad array of genes encoding regulatory system, signal transduction and methyl-accepting chemotaxis proteins, reflecting the organism's ability to respond to diverse environmental stimuli. The identification of a complete set of genes encoding the enzymes for the cobalamin biosynthetic pathway and the novel coding genes related to lipopolysaccharide biosynthesis should bring new light to the study of Leptospira physiology. Genes related to toxins, lipoproteins and several surface-exposed proteins may facilitate a better understanding of the Leptospira pathogenesis and may serve as potential candidates for vaccine.

  9. Chitinolytic activities in Bacillus thuringiensis and their synergistic effects on larvicidal activity.

    Science.gov (United States)

    Liu, M; Cai, Q X; Liu, H Z; Zhang, B H; Yan, J P; Yuan, Z M

    2002-01-01

    To investigate the distribution of chitinase in Bacillus thuringiensis strains, and the enhancing effects of the chitinase-producing B. thuringiensis strains on insecticidal toxicity of active B. thuringiensis strain against Spodoptera exigua larvae. The chitinolytic activities of B.thuringiensis strains representing the 70 serotypes were investigated by the whitish opaque halo and the colorimetric method. Thirty-eight strains produced different levels of chitinase at pH 7.0, and so did 17 strains at pH 10.0. The strain T04A001 exhibited the highest production, reaching a specific activity of 355 U ml(-1) in liquid medium. SDS-PAGE and Western blotting showed that the chitinase produced by some B. thuringiensis strains had a molecular weight of about 61 kDa. The bioassay results indicated that the chitinase-producing B. thuringiensis strains could enhance the insecticidal activity of B. thuringiensis strain DL5789 against S. exigua larvae, with an enhancing ratio of 2.35-fold. This study demonstrated that chitinase was widely produced in B. thuringiensis strains and some of the strains could enhance the toxicity of active B. thuringiensis strain. This is the first investigation devoted exclusively to analyse the distribution of chitinase in B. thuringiensis. It infers that the chitinase produced by B. thuringiensis might play a role in the activity of the biopesticide.

  10. First isolation of Salmonella enterica serovar Napoli from wild birds in Italy

    Directory of Open Access Journals (Sweden)

    Laura Mancini

    2014-03-01

    Full Text Available Salmonella enterica serovar Napoli (S. Napoli is an emerging serovar in Italy. It accounts for 2-4% of all serovars isolated from human infections. The zoonotic origin of this serovar is still unknown and this makes difficult to apply any control intervention. We report here the isolation of S. Napoli from a river nightingale (Cettia cetti, Temminck 1820 which represents the first description of this serovar from wild birds. This finding adds knowledge to the ecology of S. Napoli and addresses further studies aimed to assess the epidemiologic link between S. Napoli isolated from wild birds, food, environmental sources and human infections.

  11. ORF Sequence: NC_005957 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available 40 [Bacillus thuringiensis serovar konkukian str. 97-27] MIYIQDKNEKTKKNLLSLALEIILPYRLTGPTGITGPTGITGPTGITGPTGITGPTGFTGPTGITGPTGITGP...TGITGPTGFTGPTGITGPTGITGPTGITGPTGFTGPTGFTGPTGFTGPNITTNSMFANNTLGGPISVILGGTNIPLSNNQSLGNFT

  12. Occurrence of natural Bacillus thuringiensis contaminants and residues of Bacillus thuringiensis-based insecticides on fresh fruits and vegetables

    DEFF Research Database (Denmark)

    Frederiksen, Kristine; Rosenquist, Hanne; Jørgensen, Kirsten

    2006-01-01

    A total of 128 Bacillus cereus-like strains isolated from fresh fruits and vegetables for sale in retail shops in Denmark were characterized. Of these strains, 39% (50/128) were classified as Bacillus thuringiensis on the basis of their content of cry genes determined by PCR or crystal proteins v...... isolated from fruits and vegetables. The same was seen for a third enterotoxin, CytK. In conclusion, the present study strongly indicates that residues of B. thuringiensis-based insecticides can be found on fresh fruits and vegetables and that these are potentially enterotoxigenic....

  13. Environmental Distribution and Diversity of Insecticidal Proteins of Bacillus thuringiensis Berliner

    Directory of Open Access Journals (Sweden)

    Xavier, R.

    2007-01-01

    Full Text Available Bacillus thuringiensis Berliner based biopesticides have been successfully used world over for the control of agricultural pests and vectors of human diseases. Currently there are more than 200 B. thuringiensis strains with differing insecticidal activities are available as biocontrol agents and for developing transgenic plants. However, two major disadvantages are the development of insect resistance and high target specificity (narrow host range. Globally there is a continuous search for new B. thuringiensis strains with novel insecticidal activities. The present study aims to study the environmental distribution of B. thuringiensis and their toxic potential against insect pests. Soil and grain samples were collected from different environments and were processed by a modified acetate selection method. Initially B. thuringiensis isolates were screened on the basis of colony morphology and phase contrast microscopy for the presence of parasporal crystal inclusions. The population dynamics showed that B. thuringiensis is abundant in sericulture environment compared to other niches. Relative abundance of B. thuringiensis strains in sericulture environment shows the persistent association of B. thuringiensis with Bombyx mori (silk worm as insect pathogen. The protein profiles of the selected strains were studied by SDS-PAGE. The protein profiles of majority of B. thuringiensis isolates from grain storage facilities predominantly showing the 130 kDa and 68 kDa proteins, which is characteristics of lepidopteran active B. thuringiensis. However, one isolate BTRX-4 has 80-85 kDa protein, which is novel in that, this strain also exhibits antilepidopteran activity, which is normally presented by B. thuringiensis strains having 130 kDa and 68 kDa proteins. The protein profile of B. thuringiensis isolates from sericulture environment shows two different protein profiles. B. thuringiensis isolates BTRX-16 to BTRX-22 predominantly show 130 kDa protein

  14. 40 CFR 180.1154 - CryIA(c) and CryIC derived delta-endotoxins of Bacillus thuringiensis var. kurstaki encapsulated...

    Science.gov (United States)

    2010-07-01

    ...-endotoxins of Bacillus thuringiensis var. kurstaki encapsulated in killed Pseudomonas fluorescens, and the... Bacillus thuringiensis var. kurstaki encapsulated in killed Pseudomonas fluorescens, and the expression... thuringiensis var. kurstaki encapsulated in killed Pseudomonas fluorescens and the expression plasmid and...

  15. Prevalence and antimicrobial profiles of Salmonella serovars from ...

    African Journals Online (AJOL)

    ADEYEYE

    2014-01-21

    Jan 21, 2014 ... This study was conducted to examine vegetable from farms and market, to determine the serovars, the prevalence rate and the antimicrobial ..... Listeria monocytogenes on salad vegetables. World Journal of Microbiology and Biotechnology, 14(3): 383-387. Le Hello S, Hendriksen RS, Doublet B, Fisher I,.

  16. Prevalence and antimicrobial profiles of Salmonella serovars from ...

    African Journals Online (AJOL)

    were collected from five different farms and Maiduguri central market from May to August, 2009. Presumptive Salmonella isolates were determined by using the conventional biochemical tests, Serovars were confirmed by serotyping, using slide agglutination technique. Antimicrobial susceptibility test was performed with 17 ...

  17. Acute infection of swine by various Salmonella serovars.

    Science.gov (United States)

    Loynachan, A T; Nugent, J M; Erdman, M M; Harris, D L

    2004-07-01

    The objective of this study was to evaluate the ability of various serovars of Salmonella enterica subsp. enterica to infect alimentary and nonalimentary tissues of swine within 3 h of inoculation. Fourteen wild-type S. enterica serovars (4,12:imonophasic, 6,7 nonmotile, Agona, Brandenburg, Bredeney, Derby, Heidelberg, Infantis, Muenchen, Thompson, Typhimurium, Typhimurium variant Copenhagen, untypeable, and Worthington), two known virulent S. enterica serovars (Choleraesuis strain SC-38 and Typhimurium strain chi4232), and two avirulent S. enterica Choleraesuis vaccine strains (Argus and SC-54) were inoculated intranasally (approximately 5 x 10(9) cells) into swine (four animals per Salmonella isolate). Three hours after inoculation, animals were euthanized, and both alimentary tissues (tonsil, colon contents, and cecum contents) and nonalimentary tissues (mandibular lymph node, thymus, lung, liver, spleen, ileocecal lymph node, and blood) were collected for Salmonella isolation. All Salmonella serovars evaluated except Salmonella Choleraesuis SC-54 acutely infected both alimentary and nonalimentary tissues. These results indicate that Salmonella isolates commonly found in swine are capable of acutely infecting both alimentary and nonalimentary tissues in a time frame consistent with that in which animals are transported and held in lairage prior to slaughter.

  18. Method for the detection of Salmonella enterica serovar Enteritidis

    Energy Technology Data Exchange (ETDEWEB)

    Agron, Peter G. (Castro Valley, CA); Andersen, Gary L. (Berkeley, CA); Walker, Richard L. (Davis, CA)

    2008-10-28

    Described herein is the identification of a novel Salmonella enterica serovar Enteritidis locus that serves as a marker for DNA-based identification of this bacterium. In addition, three primer pairs derived from this locus that may be used in a nucleotide detection method to detect the presence of the bacterium are also disclosed herein.

  19. The colonization of Bacillus thuringiensis strains in bryophytes

    Czech Academy of Sciences Publication Activity Database

    Lin, Q.; Zhu, P.; Carballar-Lejarazú, R.; Gelbič, Ivan; Guan, X.; Xu, L.; Zhang, L.

    2017-01-01

    Roč. 41, č. 1 (2017), s. 41-48 ISSN 1300-0152 Institutional support: RVO:60077344 Keywords : Bacillus thuringiensis * GFP * plant colonization Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 1.038, year: 2016 http://journals.tubitak.gov.tr/biology/issues/biy-17-41-1/biy-41-1-5-1510-16.pdf

  20. Activity of Bacillis thuringiensis toxins against cocoa pod borer larvae

    NARCIS (Netherlands)

    Santoso, D.; Chaidamsari, T.; Wiryadiputra, S.; Maagd, de R.A.

    2004-01-01

    Twelve Cry proteins from Bacillus thuringiensis Berliner were tested in bioassays on cacao plantations in Indonesia for activity against the larvae of cocoa pod borer (Conopomorpha cramerella (Snellen)), an insect pest of the cacao tree. Through the damage caused by their feeding, the larvae of

  1. Midgut microbiota and host immunocompetence underlie Bacillus thuringiensis killing mechanism

    Science.gov (United States)

    Caccia, Silvia; Di Lelio, Ilaria; La Storia, Antonietta; Marinelli, Adriana; Varricchio, Paola; Franzetti, Eleonora; Banyuls, Núria; Tettamanti, Gianluca; Casartelli, Morena; Giordana, Barbara; Ferré, Juan; Gigliotti, Silvia; Pennacchio, Francesco

    2016-01-01

    Bacillus thuringiensis is a widely used bacterial entomopathogen producing insecticidal toxins, some of which are expressed in insect-resistant transgenic crops. Surprisingly, the killing mechanism of B. thuringiensis remains controversial. In particular, the importance of the septicemia induced by the host midgut microbiota is still debated as a result of the lack of experimental evidence obtained without drastic manipulation of the midgut and its content. Here this key issue is addressed by RNAi-mediated silencing of an immune gene in a lepidopteran host Spodoptera littoralis, leaving the midgut microbiota unaltered. The resulting cellular immunosuppression was characterized by a reduced nodulation response, which was associated with a significant enhancement of host larvae mortality triggered by B. thuringiensis and a Cry toxin. This was determined by an uncontrolled proliferation of midgut bacteria, after entering the body cavity through toxin-induced epithelial lesions. Consequently, the hemolymphatic microbiota dramatically changed upon treatment with Cry1Ca toxin, showing a remarkable predominance of Serratia and Clostridium species, which switched from asymptomatic gut symbionts to hemocoelic pathogens. These experimental results demonstrate the important contribution of host enteric flora in B. thuringiensis-killing activity and provide a sound foundation for developing new insect control strategies aimed at enhancing the impact of biocontrol agents by reducing the immunocompetence of the host. PMID:27506800

  2. Frequency and distribution of Bacillus Thuringiensis from Ethiopian ...

    African Journals Online (AJOL)

    Two hundred and thirteen B. thuringiensis isolates were tested for larvicidal activity against An. arabiensis (Diptera) and Plutella xylostella (Lepidoptera) larvae. Of the tested isolates, 44 (21%) killed 50-100% of An. arabiensis larvae within 48 hours. Isolates that killed 100% larvae within 24 hours were all from tepid to cool ...

  3. Bacillus thuringiensis membrane-damaging toxins acting on mammalian cells.

    Science.gov (United States)

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

    2014-12-01

    Bacillus thuringiensis is widely used as a biopesticide in forestry and agriculture, being able to produce potent species-specific insecticidal toxins and considered nonpathogenic to other animals. More recently, however, repeated observations are documenting the association of this microorganism with various infectious diseases in humans, such as food-poisoning-associated diarrheas, periodontitis, bacteremia, as well as ocular, burn, and wound infections. Similar to B. cereus, B. thuringiensis produces an array of virulence factors acting against mammalian cells, such as phosphatidylcholine- and phosphatidylinositol-specific phospholipase C (PC-PLC and PI-PLC), hemolysins, in particular hemolysin BL (HBL), and various enterotoxins. The contribution of some of these toxins to B. thuringiensis pathogenicity has been studied in animal models of infection, following intravitreous, intranasal, or intratracheal inoculation. These studies lead to the speculation that the activities of PC-PLC, PI-PLC, and HBL are responsible for most of the pathogenic properties of B. thuringiensis in nongastrointestinal infections in mammals. This review summarizes data regarding the biological activity, the genetic basis, and the structural features of these membrane-damaging toxins. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  4. Structural Insights into Bacillus thuringiensis Cry, Cyt and Parasporin Toxins

    Science.gov (United States)

    Xu, Chengchen; Wang, Bi-Cheng; Yu, Ziniu; Sun, Ming

    2014-01-01

    Since the first X-ray structure of Cry3Aa was revealed in 1991, numerous structures of B. thuringiensis toxins have been determined and published. In recent years, functional studies on the mode of action and resistance mechanism have been proposed, which notably promoted the developments of biological insecticides and insect-resistant transgenic crops. With the exploration of known pore-forming toxins (PFTs) structures, similarities between PFTs and B. thuringiensis toxins have provided great insights into receptor binding interactions and conformational changes from water-soluble to membrane pore-forming state of B. thuringiensis toxins. This review mainly focuses on the latest discoveries of the toxin working mechanism, with the emphasis on structural related progress. Based on the structural features, B. thuringiensis Cry, Cyt and parasporin toxins could be divided into three categories: three-domain type α-PFTs, Cyt toxin type β-PFTs and aerolysin type β-PFTs. Structures from each group are elucidated and discussed in relation to the latest data, respectively. PMID:25229189

  5. The use of two biological formulations of Bacillus Thuringiensis and ...

    African Journals Online (AJOL)

    Two biological formulations of the microbial agents Bacillus thuringiensis and Bacillus sphaericus, known by their trade names Vectobac 12 AS and VectoLex CG (Corn Cob) granules, respectively, were obtained from Valent Biosciences Company (formerly Abbott Laboratories) of North Chicago, USA, and applied to control ...

  6. Profile of cry from native Bacillus thuringiensis isolates and ...

    African Journals Online (AJOL)

    oyaide

    2013-05-29

    May 29, 2013 ... The characterization of 255 Bacillus thuringiensis isolates of Coorg, Sharavatti and BR hills, containing genes known to be active against coleopteran and lepidopteran insect species was done through PCR amplification using the specific and degenerate primers. The isolates were also tested for their.

  7. Structural Insights into Bacillus thuringiensis Cry, Cyt and Parasporin Toxins

    Directory of Open Access Journals (Sweden)

    Chengchen Xu

    2014-09-01

    Full Text Available Since the first X-ray structure of Cry3Aa was revealed in 1991, numerous structures of B. thuringiensis toxins have been determined and published. In recent years, functional studies on the mode of action and resistance mechanism have been proposed, which notably promoted the developments of biological insecticides and insect-resistant transgenic crops. With the exploration of known pore-forming toxins (PFTs structures, similarities between PFTs and B. thuringiensis toxins have provided great insights into receptor binding interactions and conformational changes from water-soluble to membrane pore-forming state of B. thuringiensis toxins. This review mainly focuses on the latest discoveries of the toxin working mechanism, with the emphasis on structural related progress. Based on the structural features, B. thuringiensis Cry, Cyt and parasporin toxins could be divided into three categories: three-domain type α-PFTs, Cyt toxin type β-PFTs and aerolysin type β-PFTs. Structures from each group are elucidated and discussed in relation to the latest data, respectively.

  8. Effects of Ingesting Bacillus Thuringiensis (Berliner) Spores on ...

    African Journals Online (AJOL)

    Bacillus thuringiensis Berliner was isolated from dead Sesamia calamistis Hampson (Lepidoptera: Noctuidae) larvae collected from maize farms in Cape Coast, Ghana. Spores produced from the vegetative cells were incorporated into an artificial diet and fed to 2nd instar S. calamistis larvae. The duration of larval and pupal ...

  9. Laboratory evaluation of toxicity of Bacillus thuringiensis , neem oil ...

    African Journals Online (AJOL)

    Diamondback moth (DBM), Plutella xylostella (L.), remains a major pest of brassica crops worldwide. Chemical control of this pest remains difficult due to the rapid development of resistance to insecticides and to their effect on natural enemies. The objective of this study was to assess the toxicity of Bacillus thuringiensis (Bt), ...

  10. Bacillus thuringiensis and its application in agriculture | Ali | African ...

    African Journals Online (AJOL)

    Presently, a number of approaches to pest control via genetic engineering have been developed and genetically engineered crops expressing insecticidal characteristics are under cultivation for the last 15 years. Use of Bacillus thuringiensis genes encoding o̅ endotoxins with insecticidal characteristics is the major ...

  11. Evaluation of potency of native Bacillus thuringiensis against maize ...

    African Journals Online (AJOL)

    Bacillus thuringiensis is the most used biological control agent to date. Among major constraints to maize production, safety and hence food sufficiency in Kenya is infestation, damage and contamination by insect pests. Maize grains are adversely damaged by. Prostephanus truncatus which occasionally paves way for the ...

  12. Effects of Ingesting Bacillus Thuringiensis (Berliner) Spores on ...

    African Journals Online (AJOL)

    Effects of Ingesting Bacillus Thuringiensis (Berliner) Spores on Developmental Stages and Fecundity of Surviving Sesamia Calamistis (Hampson) (Lepidoptera: ... The PDF file you selected should load here if your Web browser has a PDF reader plug-in installed (for example, a recent version of Adobe Acrobat Reader).

  13. Screening of Local Bacillus thuringiensis Isolates for Toxicity to ...

    African Journals Online (AJOL)

    Stem borers are a major source of pre-harvest maize crop losses in Kenya and many Sub- Saharan African countries. This menace needs to be addressed if food security is to be realized in this region. Seven local isolates of Bacillus thuringiensis (Bt) strains were isolated from soils collected from Kakamega and Machakos ...

  14. The Impact of Bacillus Thuringiensis Israelensis (Bti) on Adult and ...

    African Journals Online (AJOL)

    In the year 2007, the Ministry of Health (MoH) initiated a larviciding program using Bacillus thuringiensis israelensis (Bti) to mitigate the effects of black fly bites. This study was aimed at assessing the impact of Bti on adult and larvae black fly populations. Baseline data was collected prior to Bti application and after ...

  15. Profile of cry from native Bacillus thuringiensis isolates and ...

    African Journals Online (AJOL)

    The characterization of 255 Bacillus thuringiensis isolates of Coorg, Sharavatti and BR hills, containing genes known to be active against coleopteran and lepidopteran insect species was done through PCR amplification using the specific and degenerate primers. The isolates were also tested for their insecticidal activity ...

  16. Impacts of Bacillus thuringiensis var. israelensis and Bacillus ...

    African Journals Online (AJOL)

    The study assessed the impact of bio-larvicides- Bacillus thuringiensis var. israelensis (Bti) and B. sphaericus (Bs) on anopheline mosquito larval densities in four selected areas of Lusaka urban district. Larval densities were determined using a standard WHO protocol at each study area prior to and after larviciding.

  17. Detection of Bacillus thuringiensis genes in transgenic maize by the ...

    African Journals Online (AJOL)

    We optimized the PCR method to detect genetically engineered Bacillus thuringiensis (Bt) maize in open quarantine fields in Kenya. Many factors affect the extraction of the DNA from plants, such as the amount of tissue available, the condition of the plant material, the numbers of steps involved in the extraction procedure, ...

  18. Antagonistic activity of selected strains of Bacillus thuringiensis ...

    African Journals Online (AJOL)

    The aim of this work was to determine, in vitro, the antagonistic effectiveness of 60 strains of Bacillus thuringiensis against damping-off and root and stem rot caused by Rhizoctonia solani. The strains were obtained from the International Collection of Entomopathogenic Bacillus at the FCB-UANL. During the in vitro dual ...

  19. Emergence of new leptospiral serovars in American Samoa - ascertainment or ecological change?

    Directory of Open Access Journals (Sweden)

    Lau Colleen L

    2012-01-01

    Full Text Available Abstract Background Leptospirosis has recently been discussed as an emerging infectious disease in many contexts, including changes in environmental drivers of disease transmission and the emergence of serovars. In this paper, we report the epidemiology of leptospiral serovars from our study of human leptospirosis in American Samoa in 2010, present evidence of recent serovar emergence, and discuss the potential epidemiological and ecological implications of our findings. Methods Serovar epidemiology from our leptospirosis seroprevalence study in 2010 was compared to findings from a study in 2004. The variation in geographic distribution of the three most common serovars was explored by mapping sero-positive participants to their place of residence using geographic information systems. The relationship between serovar distribution and ecological zones was examined using geo-referenced data on vegetation type and population distribution. Results Human leptospirosis seroprevalence in American Samoa was 15.5% in 2010, with serological evidence that infection was caused by three predominant serovars (Hebdomadis, LT 751, and LT 1163. These serovars differed from those identified in an earlier study in 2004, and were not previously known to occur in American Samoa. In 2010, serovars also differed in geographic distribution, with variations in seroprevalence between islands and different ecological zones within the main island. Conclusions Our findings might indicate artefactual emergence (where serovars were long established but previously undetected, but we believe the evidence is more in favour of true emergence (a result of ecological change. Possibilities include changes in interactions between humans and the environment; introduction of serovars through transport of animals; evolution in distribution and/or abundance of animal reservoirs; and environmental changes that favour transmission of particular serovars. Future research should explore the

  20. Listeria monocytogenes serovar 4a is a possible evolutionary intermediate between L. monocytogenes serovars 1/2a and 4b and L. innocua.

    Science.gov (United States)

    Chen, Jianshun; Jiang, Lingli; Chen, Xueyan; Luo, Xiaokai; Chen, Yang; Yu, Ying; Tian, Guoming; Liu, Dongyou; Fang, Weihuan

    2009-03-01

    The genus Listeria consists of six closely related species and forms three phylogenetic groups: L. monocytogenes- L. innocua, L. ivanovii-L. seeligeri-L. welshimeri, and L. grayi. In this report, we attempted to examine the evolutionary relationship in the L. monocytogenes-L. innocua group by probing the nucleotide sequences of 23S rRNA and 16S rRNA, and the gene clusters lmo0029-lmo0042, ascBdapE, rplS-infC, and prs-ldh in L. monocytogenes serovars 1/2a, 4a, and 4b, and L. innocua. Additionally, we assessed the status of L. monocytogenes-specific inlA and inlB genes and 10 L. innocua-specific genes in these species/serovars, together with phenotypic characterization by using in vivo and in vitro procedures. The results indicate that L. monocytogenes serovar 4a strains are genetically similar to L. innocua in the lmo0035-lmo0042, ascB-dapE, and rplS-infC regions and also possess L. innocua-specific genes lin0372 and lin1073. Furthermore, both L. monocytogenes serovar 4a and L. innocua exhibit impaired intercellular spread ability and negligible pathogenicity in mouse model. On the other hand, despite resembling L. monocytogenes serovars 1/2a and 4b in having a nearly identical virulence gene cluster, and inlA and inlB genes, these serovar 4a strains differ from serovars 1/2a and 4b by harboring notably altered actA and plcB genes, displaying strong phospholipase activity and subdued in vivo and in vitro virulence. Thus, by possessing many genes common to L. monocytogenes serovars 1/2a and 4b, and sharing many similar gene deletions with L. innocua, L. monocytogenes serovar 4a represents a possible evolutionary intermediate between L. monocytogenes serovars 1/2a and 4b and L. innocua.

  1. Development of a multiplex PCR test for identification of Actinobacillus pleuropneumoniae serovars 1, 7, and 12

    DEFF Research Database (Denmark)

    Angen, Øystein; Ahrens, Peter; Jessing, Stine Graakjær

    2008-01-01

    A PCR assay for simultaneous species identification and separation of Actinobacillus pleuropneumoniae serovars 1, 7 and 12 was developed. Primers specific for genes involved in biosynthesis of the capsular polysaccharides (cps genes) of serovars 1, 7,and 12 were combined with a species-specific PCR...... serotyping methods. Among eight serologically cross-reacting strains designated K1:O7, seven isolates produced amplicons of similar sizes as serovar 1 and one isolate produced amplicons of similar sizes as serovar 7. The species specificity of the assay was evaluated using a collection of 126 strains...... produced an amplicon identical to the cps gene of serovar 7, whereas one isolate produced an amplicon identical to the cps gene of serovar 1. In addition, four isolates of Actinobacillus genomospecies 1 tested positive for the omlA gene but negative for the cps genes. The test represents a convenient...

  2. Pengaruh Bacillus Thuringiensis terhadap penggerek batang jagung Ostrinia Furnacalis (Lep. Pyralidae

    Directory of Open Access Journals (Sweden)

    Harnoto Harnoto

    2017-02-01

    Full Text Available The effect of Bacillus thuringiensis to the mortality of corn stemborer Ostrinia furnacalis (Lep. Pyralidae. The study was conducted at the laboratory of Bogor Research Institute for Agricultural Biotechnology and Genetic Resources during 2005. The objective of this study was to evaluate the effect of the dosages of Bacillus. thuringiensis var. aizawai and var. Kurstaki on the mortalities of larvae of corn stemborer Ostrinia furnacalis. Completely randomize design was used with seven treatments. Each treatment was repeated four time with ten larvae per replication. The treatments were three formulation dosages of B. thuringiensis var. aizawai, i.e. 0,5; 1,0; and 2,0 g/l, thee formulation dosages of B. thuringiensis var. Kurstaki, i.e. 0,5; 1,0; and 2,0 g/l, and untreated control. Second instar larvae of O. furnacalis was used in this study. B. thuringiensis was contaminated to the surface of artificial diet with a small paint brush. The result showed that B. thuringiensis var. kurstaki at the dose rate of 1,0 g/l was toxic to the test insect while B. thuringiensis var. aizawai at the dose rate of 2,0 g/l was toxic to the test insect B. thuringiensis var. kurstaki was more toxic than  B. thuringiensis var. aizawai to the corn stemborer.

  3. Construction of Bacillus thuringiensis Simulant Strains Suitable for Environmental Release.

    Science.gov (United States)

    Park, Sangjin; Kim, Changhwan; Lee, Daesang; Song, Dong Hyun; Cheon, Ki Cheol; Lee, Hong Suk; Kim, Seong Joo; Kim, Jee Cheon; Lee, Sang Yup

    2017-05-01

    For a surrogate bacterium to be used in outdoor studies, it is important to consider environmental and human safety and ease of detection. Recently, Bacillus thuringiensis , a popular bioinsecticide bacterium, has been gaining attention as a surrogate bacterium for use in biodefense. In this study, we constructed simulant strains of B. thuringiensis with enhanced characteristics for environmental studies. Through transposon mutagenesis, pigment genes were inserted into the chromosome, producing yellow-colored colonies for easy detection. To prevent persistence of spores in the environment, a genetic circuit was designed to produce a spore without sporulation capability. Two loxP sites were inserted, one on each side of the spo0A gene, which encodes a sporulation master regulator, and a sporulation-dependent Cre expression cassette was inserted into the chromosome. This genetic circuit successfully deleted spo0A during sporulation, producing spores that lacked the spo0A gene. In addition, two major α/β-type small acid-soluble spore protein (SASP) genes, predicted by synteny analysis, were deleted. The spores of the mutant strain showed increased UV-C sensitivity and quickly lost viability when tested in a solar simulator. When the spores of the mutant strain were administered to the lungs of BALB/c mice, cells were quickly removed from the body, suggesting enhanced in vivo safety. All strains constructed in this study contain no antibiotic resistance markers and all heterologous genes were inserted into the chromosome, which are useful features for simulants to be released into the environment. IMPORTANCE B. thuringiensis has recently been receiving increasing attention as a good spore simulant in biodefense research. However, few studies were done to properly address many important features of B. thuringiensis as a simulant in environmental studies. Since spores can persist in the environment for years after release, environmental contamination is a big problem

  4. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Science.gov (United States)

    2010-07-01

    ... thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement... into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens is...

  5. Comparative genomics of pathogenic Leptospira interrogans serovar Canicola isolated from swine and human in Brazil

    Directory of Open Access Journals (Sweden)

    Luisa Z Moreno

    Full Text Available Leptospira interrogans serovar Canicola is one of the most important pathogenic serovars for the maintenance of urban leptospirosis. Even though it is considered highly adapted to dogs, serovar Canicola infection has already been described in other animals and even a few human cases. Here, we present the genomic characterisation of two Brazilian L. interrogans serovar Canicola strains isolated from slaughtered sows (L0-3 and L0-4 and their comparison with human strain Fiocruz LV133. It was observed that the porcine serovar Canicola strains present the genetic machinery to cause human infection and, therefore, represent a higher risk to public health. Both human and porcine serovar Canicola isolates also presented sequences with high identity to the Chinese serovar Canicola published plasmids pGui1 and pGui2. The plasmids identification in the Brazilian and Chinese serovar Canicola strains suggest that extra-chromosomal elements are one more feature of this serovar that was previously unnoticed.

  6. Serovar distribution of a DNA sequence involved in the antigenic relationship between Leptospira and equine cornea

    Directory of Open Access Journals (Sweden)

    Arroyo Guillermo H

    2002-02-01

    Full Text Available Abstract Background Horses infected with Leptospira present several clinical disorders, one of them being recurrent uveitis. A common endpoint of equine recurrent uveitis is blindness. Serovar pomona has often been incriminated, although others have also been reported. An antigenic relationship between this bacterium and equine cornea has been described in previous studies. A leptospiral DNA fragment that encodes cross-reacting epitopes was previously cloned and expressed in Escherichia coli. Results A region of that DNA fragment was subcloned and sequenced. Samples of leptospiral DNA from several sources were analysed by PCR with two primer pairs designed to amplify that region. Reference strains from serovars canicola, icterohaemorrhagiae, pomona, pyrogenes, wolffi, bataviae, sentot, hebdomadis and hardjo rendered products of the expected sizes with both pairs of primers. The specific DNA region was also amplified from isolates from Argentina belonging to serogroups Canicola and Pomona. Both L. biflexa serovar patoc and L. borgpetersenii serovar tarassovi rendered a negative result. Conclusions The DNA sequence related to the antigen mimicry with equine cornea was not exclusively found in serovar pomona as it was also detected in several strains of Leptospira belonging to different serovars. The results obtained with L. biflexa serovar patoc strain Patoc I and L. borgpetersenii serovar tarassovi strain Perepelicin suggest that this sequence is not present in these strains, which belong to different genomospecies than those which gave positive results. This is an interesting finding since L. biflexa comprises nonpathogenic strains and serovar tarassovi has not been associated clinically with equine uveitis.

  7. Hatchery-borne Salmonella enterica serovar Tennessee infections in broilers

    DEFF Research Database (Denmark)

    Christensen, J.P.; Brown, D.J.; Madsen, Mogens

    1997-01-01

    A substantial increase in the prevalence of S. enterica serovar Tennessee was observed in broiler flocks in Denmark at the turn of the year 1994 and in the following months. Epidemiological data indicated that a single hatchery was involved in spreading of the infection. Molecular characterization...... of S. enterica serovar Tennessee isolates from Danish broilers (1992 to 1995), the suspected hatchery and strains from various other sources included for comparison was initiated in order to trace the source of infection of the broilers. In general, strains of S. enterica ser. Tennessee showed only....... Restriction enzyme analysis of the plasmid ensured that the plasmids from broilers and the hatchery were identical. By analysis of cleaning and disinfection procedures and by sampling of different control points in the hatchery it was shown that S. enterica ser. Tennessee had colonized areas of the hatchers...

  8. Effects of propolis from Brazil and Bulgaria on Salmonella serovars

    Directory of Open Access Journals (Sweden)

    R. O. Orsi

    2007-01-01

    Full Text Available Propolis shows biological properties such as antibacterial action. This bee product has a complex chemical composition, which depends on the local flora where it is produced. Salmonella serovars are responsible for human diseases that range from localized gastroenteritis to systemic infections. The aim of the present study was to investigate the susceptibility of Salmonella strains, isolated from food and infectious processes, to the antibacterial action of Brazilian and Bulgarian propolis, as well as to determine the behavior of these bacteria, according to the incubation period, in medium plus propolis. Dilution of ethanolic extract of propolis in agar was the used method. Brazilian and Bulgarian propolis showed an antibacterial action against all Salmonella serovars. The minimal inhibitory concentrations (MIC of propolis were similar, although they were collected in different geographic regions. Salmonella typhimurium, isolated from human infection, was more resistant to propolis than Salmonella enteritidis.

  9. Salmonella Pathogenicity and Host Adaptation in Chicken-Associated Serovars

    Science.gov (United States)

    Johnson, Timothy J.; Ricke, Steven C.; Nayak, Rajesh; Danzeisen, Jessica

    2013-01-01

    SUMMARY Enteric pathogens such as Salmonella enterica cause significant morbidity and mortality. S. enterica serovars are a diverse group of pathogens that have evolved to survive in a wide range of environments and across multiple hosts. S. enterica serovars such as S. Typhi, S. Dublin, and S. Gallinarum have a restricted host range, in which they are typically associated with one or a few host species, while S. Enteritidis and S. Typhimurium have broad host ranges. This review examines how S. enterica has evolved through adaptation to different host environments, especially as related to the chicken host, and continues to be an important human pathogen. Several factors impact host range, and these include the acquisition of genes via horizontal gene transfer with plasmids, transposons, and phages, which can potentially expand host range, and the loss of genes or their function, which would reduce the range of hosts that the organism can infect. S. Gallinarum, with a limited host range, has a large number of pseudogenes in its genome compared to broader-host-range serovars. S. enterica serovars such as S. Kentucky and S. Heidelberg also often have plasmids that may help them colonize poultry more efficiently. The ability to colonize different hosts also involves interactions with the host's immune system and commensal organisms that are present. Thus, the factors that impact the ability of Salmonella to colonize a particular host species, such as chickens, are complex and multifactorial, involving the host, the pathogen, and extrinsic pressures. It is the interplay of these factors which leads to the differences in host ranges that we observe today. PMID:24296573

  10. Conjugative plasmid pAW63 brings new insights into the genesis of the Bacillus anthracis virulence plasmid pXO2 and of the Bacillus thuringiensis plasmid pBT9727

    Directory of Open Access Journals (Sweden)

    Mahillon Jacques

    2005-07-01

    Full Text Available Abstract Background Bacillus cereus, Bacillus anthracis and Bacillus thuringiensis belong to the genetically close-knit Bacillus cereus sensu lato group, a family of rod-shaped Gram-positive bacteria. pAW63 is the first conjugative plasmid from the B. cereus group to be completely sequenced. Results The 71,777 bp nucleotide sequence of pAW63 reveals a modular structure, including a 42 kb tra region encoding homologs of the Type IV secretion systems components VirB11, VirB4 and VirD4, as well as homologs of Gram-positive conjugation genes from Enterococcus, Lactococcus, Listeria, Streptococcus and Staphylococcus species. It also firmly establishes the existence of a common backbone between pAW63, pXO2 from Bacillus anthracis and pBT9727 from the pathogenic Bacillus thuringiensis serovar konkukian strain 97-27. The alignment of these three plasmids highlights the presence of well conserved segments, in contrast to distinct regions of high sequence plasticity. The study of their specific differences has provided a three-point reference framework that can be exploited to formulate solid hypotheses concerning the functionalities and the molecular evolution of these three closely related plasmids. This has provided insight into the chronology of their divergence, and led to the discovery of two Type II introns on pAW63, matching copies of the mobile element IS231L in different loci of pXO2 and pBT9727, and the identification on pXO2 of a 37 kb pathogenicity island (PAI containing the anthrax capsule genes. Conclusion The complete sequence determination of pAW63 has led to a functional map of the plasmid yielding insights into its conjugative apparatus, which includes T4SS-like components, as well as its resemblance to other large plasmids of Gram-positive bacteria. Of particular interest is the extensive homology shared between pAW63 and pXO2, the second virulence plasmid of B. anthracis, as well as pBT9727 from the pathogenic strain B. thuringiensis

  11. 40 CFR 174.517 - Bacillus thuringiensis Cry9C protein in corn; 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 thuringiensis Cry9C protein... PLANT-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.517 Bacillus thuringiensis... Bacillus thuringiensis Cry9C protein in corn is exempted from the requirement of a tolerance for residues...

  12. 40 CFR 174.509 - Bacillus thuringiensis Cry3A protein; 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 thuringiensis Cry3A protein...-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.509 Bacillus thuringiensis Cry3A protein; exemption from the requirement of a tolerance. Residues of Bacillus thuringiensis Cry3A protein are exempted...

  13. 40 CFR 174.520 - Bacillus thuringiensis Cry1F protein in corn; 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 thuringiensis Cry1F protein... PLANT-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.520 Bacillus thuringiensis Cry1F protein in corn; exemption from the requirement of a tolerance. Residues of Bacillus thuringiensis...

  14. 40 CFR 174.502 - Bacillus thuringiensis Cry1A.105 protein; 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 thuringiensis Cry1A.105...-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.502 Bacillus thuringiensis Cry1A.105 protein; exemption from the requirement of a tolerance. (a) Residues of Bacillus thuringiensis Cry1A.105 protein in...

  15. 40 CFR 174.529 - Bacillus thuringiensis modified Cry1Ab protein as identified under OECD Unique Identifier SYN...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus thuringiensis modified Cry1Ab... Tolerance Exemptions § 174.529 Bacillus thuringiensis modified Cry1Ab protein as identified under OECD... Bacillus thuringiensis modified Cry1Ab protein as identified under OECD Unique Identifier SYN-IR67B-1 are...

  16. 40 CFR 174.530 - Bacillus thuringiensis Cry2Ae protein in cotton; temporary exemption from the requirement of a...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus thuringiensis Cry2Ae protein... Bacillus thuringiensis Cry2Ae protein in or on the food commodities of cotton, cotton; cotton, undelinted... byproducts are exempt temporarily from the requirement of a tolerance when Bacillus thuringiensis Cry2Ae...

  17. Methodology for fast evaluation of Bacillus thuringiensis crystal protein content

    Directory of Open Access Journals (Sweden)

    Alves Lúcia M. Carareto

    2000-01-01

    Full Text Available The development of the production and use of Bacillus thuringiensis in Brazil at a commercial scale faces certain difficulties, among them the establishment of efficient methodologies for the quantitation of toxic products to be commercialized. Presently, the amount of toxin is given in percentage by analyzing the samples total protein content. Such methodology however, does not measure the actual amount of active protein present in the product, since most strains express different endotoxin genes and might even produce b-toxin. Since the various types of toxins exhibit different antigenic characteristics, this work has as objective the utilization of fast immunological techniques to quantify the level of crystal protein. Crystal protein produced by a subspecies of Bacillus thuringiensis var. israelensis was purified by ultracentrifugation and utilized to immunize rabbits and to produce hiperimmune sera. Such sera were latter used to evaluate the level of proteins on commercial bioinsecticide and on laboratory cultures of B. thuringiensis through the immunodot technique. The results were obtained by comparison of data obtained from reactions with known concentrations of crystal protein permitting to evaluate the level of such protein on various materials.

  18. Siderophores of Bacillus anthracis, Bacillus cereus, and Bacillus thuringiensis.

    Science.gov (United States)

    Wilson, Melissa K; Abergel, Rebecca J; Raymond, Kenneth N; Arceneaux, Jean E L; Byers, B Rowe

    2006-09-15

    Three Bacillus anthracis Sterne strains (USAMRIID, 7702, and 34F2) and Bacillus cereus ATCC 14579 excrete two catecholate siderophores, petrobactin (which contains 3,4-dihydroxybenzoyl moieties) and bacillibactin (which contains 2,3-dihydroxybenzoyl moieties). However, the insecticidal organism Bacillus thuringiensis ATCC 33679 makes only bacillibactin. Analyses of siderophore production by previously isolated [Cendrowski et al., Mol. Microbiol. 52 (2004) 407-417] B. anthracis mutant strains revealed that the B. anthracis bacACEBF operon codes for bacillibactin production and the asbAB gene region is required for petrobactin assembly. The two catecholate moieties also were synthesized by separate routes. PCR amplification identified both asbA and asbB genes in the petrobactin producing strains whereas B. thuringiensis ATCC 33679 retained only asbA. Petrobactin synthesis is not limited to the cluster of B. anthracis strains within the B. cereus sensu lato group (in which B. cereus, B. anthracis, and B. thuringiensis are classified), although petrobactin might be prevalent in strains with pathogenic potential for vertebrates.

  19. [Bioconversion of sewage sludge to biopesticide by Bacillus thuringiensis].

    Science.gov (United States)

    Chang, Ming; Zhou, Shun-gui; Lu, Na; Ni, Jin-ren

    2006-07-01

    Feasibility of bioconversion of sewage sludge to biopesticide by Bacillus thuringiensis was studied using sewage sludge as a raw material. The fermentation was also compared with conventional medium. Results showed that without any pretreatment, the nutrients contained in sewage sludge were almost sufficient for Bacillus thuringiensis growth, even with a rapid multiplicational rate. Higher viable cells and viable spores values were obtained earlier at 24 h, with 9.48 x 10(8) CFU x mL(-1) and 8.51 x 10(8) CFU x mL(-1) respectively, which was 12 hours earlier and nearly 20 percent higher than conventional medium. SEM of 36 h samples gave a clear phenomenon that the metabolizability in sludge was much faster with spores and crystals spreading around. The crystals in sludge seemed rather bigger and more regular. Also a better crystal protein yield of 2.80 mg x mL(-1) was observed in sludge medium compared to conventional medium at the end of fermentation. Sludge fermentation for Bacillus thuringiensis reduces the producing cost, and gives better fermentation capabilities. It's expected to be a new method for sludge disposal.

  20. Urogenital Chlamydia trachomatis serovars in men and women with a symptomatic or asymptomatic infection : an association with clinical manifestations?

    NARCIS (Netherlands)

    Morre, SA; Rozendaal, L; van Valkengoed, IGM; Boeke, AJP; Vader, PCV; Schirm, J; de Blok, S; van den Hoek, JAR; van Doornum, GJJ; Meijer, CJLM; van den Brule, AJC

    To determine whether certain Chlamydia trachomatis serovars are preferentially associated with a symptomatic or an asymptomatic course of infection, C. trachomatis serovar distributions were analyzed in symptomatically and asymptomatically infected persons. Furthermore, a possible association

  1. A Unique Capsule Locus in the Newly Designated Actinobacillus pleuropneumoniae Serovar 16 and Development of a Diagnostic PCR Assay.

    Science.gov (United States)

    Bossé, Janine T; Li, Yanwen; Sárközi, Rita; Gottschalk, Marcelo; Angen, Øystein; Nedbalcova, Katerina; Rycroft, Andrew N; Fodor, László; Langford, Paul R

    2017-03-01

    Actinobacillus pleuropneumoniae causes pleuropneumonia, an economically significant lung disease of pigs. Recently, isolates of A. pleuropneumoniae that were serologically distinct from the previously characterized 15 serovars were described, and a proposal was put forward that they comprised a new serovar, serovar 16. Here we used whole-genome sequencing of the proposed serovar 16 reference strain A-85/14 to confirm the presence of a unique capsular polysaccharide biosynthetic locus. For molecular diagnostics, primers were designed from the capsule locus of strain A-85/14, and a PCR was formulated that differentiated serovar 16 isolates from all 15 known serovars and other common respiratory pathogenic/commensal bacteria of pigs. Analysis of the capsule locus of strain A-85/14 combined with the previous serological data show the existence of a sixteenth serovar-designated serovar 16-of A. pleuropneumoniae . Copyright © 2017 Bossé et al.

  2. A novel Salmonella serovar isolated from Peregrine Falcon (Falco peregrinus) nestlings in Sweden: Salmonella enterica enterica serovar Pajala (Salmonella Pajala)

    OpenAIRE

    Hernández, Jorge; Lindberg, Peter; Waldenström, Jonas; Drobni, Mirva; Olsen, Björn

    2012-01-01

    A novel Salmonella serovar was isolated from Peregrine falcon (Falco peregrinus) nestlings in northern Sweden in 2006. Three isolates of the same clone was retrieved from three falcon siblings and characterized as Salmonella enterica sub-species enterica: O-phase 13, 23:-: e, n, z 15 and the H-phase was not present. We propose the geographical name Salmonella enterica, sub-species entericaserovar Pajala to this novel Salmonella.Keywords: Salmonella; epidemiology; ecology; peregrine falcon; no...

  3. Characterization of Isolates of Salmonella enterica Serovar Stanley, a Serovar Endemic to Asia and Associated with Travel

    Science.gov (United States)

    Le Hello, Simon; Bortolaia, Valeria; Pulsrikarn, Chaiwat; Nielsen, Eva Møller; Pornruangmong, Srirat; Chaichana, Phattharaporn; Svendsen, Christina Aaby; Weill, François-Xavier; Aarestrup, Frank M.

    2012-01-01

    Salmonella enterica serovar Stanley (S. Stanley) is a common serovar in Southeast Asia and was the second most common serovar implicated in human salmonellosis in Thailand in the years 2002 to 2007. In contrast, this serovar is relatively uncommon in Europe. The objective of this study was to characterize a collection of S. Stanley strains isolated from Thai (n = 62), Danish (n = 39), and French (n = 24) patients to gain a broader understanding of the genetic diversity, population dynamics, and susceptibility to antimicrobials. All isolates were characterized by pulsed-field gel electrophoresis and antimicrobial susceptibility testing. The molecular mechanisms of resistance to extended-spectrum cephalosporins and plasmid-mediated resistance to quinolones were characterized by PCR and sequencing. Plasmid profiling, replicon typing, and microarray analysis were used to characterize the genetic mechanisms of antimicrobial resistance in 10 extended-spectrum cephalosporinase-producing isolates. Considerable genetic diversity was observed among the isolates characterized with 91 unique XbaI pulsed-field gel electrophoresis (PFGE) patterns, including 17 distinct clusters consisting of two to seven indistinguishable isolates. We found some of the S. Stanley isolates isolated from patients in Europe were acquired during travel to Southeast Asia, including Thailand. The presence of multiple plasmid lineages carrying the extended-spectrum cephalosporinase-encoding blaCMY-2 gene in S. Stanley isolates from the central part of Thailand was confirmed. Our results emphasize that Thai authorities, as well as authorities in other countries lacking prudent use of antimicrobials, should improve the ongoing efforts to regulate antimicrobial use in agriculture and in clinical settings to limit the spread of multidrug-resistant Salmonella isolates and plasmids among humans and pigs in Thailand and abroad. PMID:22205822

  4. Prevalence and Toxin Characteristics of Bacillus thuringiensis Isolated from Organic Vegetables.

    Science.gov (United States)

    Kim, Jung-Beom; Choi, Ok-Kyung; Kwon, Sun-Mok; Cho, Seung-Hak; Park, Byung-Jae; Jin, Na Young; Yu, Yong Man; Oh, Deog-Hwan

    2017-08-28

    The prevalence and toxin characteristics of Bacillus thuringiensis isolated from 39 organic vegetables were investigated. B. thuringiensis was detected in 30 out of the 39 organic vegetables (76.9%) with a mean value of 2.60 log CFU/g. Twenty-five out of the 30 B. thuringiensis isolates (83.3%) showed insecticidal toxicity against Spodoptera exigua . The hblCDA, nheABC , and entFM genes were found to be the major toxin genes, but the ces gene was not detected in any of the tested B. thuringiensis isolates. The hemolysin BL enterotoxin was detected in all 30 B. thuringiensis isolates (100%). The non-hemolytic enterotoxin complex was found in 27 out of 30 B. thuringiensis isolates (90.0%). The B. thuringiensis tested in this study had similar toxin gene characteristics to B. cereus , which possessed more than one toxin gene. B. thuringiensis could have the potential risk of foodborne illness based on the toxin genes and toxin-producing ability.

  5. Constitutive Activation of the Midgut Response to Bacillus thuringiensis in Bt-Resistant Spodoptera exigua

    NARCIS (Netherlands)

    Hernandez-Martinez, P.; Navarro-Cerrillo, G.; Caccia, S.; Maagd, de R.A.; Moar, W.J.; Ferre, J.; Escriche, B.; Herrero, S.

    2010-01-01

    Bacillus thuringiensis is the most effective microbial control agent for controlling numerous species from different insect orders. The main threat for the long term use of B. thuringiensis in pest control is the ability of insects to develop resistance. Thus, the identification of insect genes

  6. SR450 and Superhawk XP applications of Bacillus thuringiensis israelensis de Barjac against Culex quinquefasciatus Say

    Science.gov (United States)

    Sprayer comparisons and larval morality assays were conducted following SR450 backpack mist blower and Superhawk XP thermal fogger applications of Vectobac® WDG Bacillus thuringiensis israelensis (Bti) de Barjac against Culex quinquefasciatus Say. Bacillus thuringiensis israelensis was applied at m...

  7. Contributions of gut bacteria to Bacillus thuringiensis-induced mortality vary across a range of Lepidoptera

    Science.gov (United States)

    Broderick, Nichole A; Robinson, Courtney J; McMahon, Matthew D; Holt, Jonathan; Handelsman, Jo; Raffa, Kenneth F

    2009-01-01

    Background Gut microbiota contribute to the health of their hosts, and alterations in the composition of this microbiota can lead to disease. Previously, we demonstrated that indigenous gut bacteria were required for the insecticidal toxin of Bacillus thuringiensis to kill the gypsy moth, Lymantria dispar. B. thuringiensis and its associated insecticidal toxins are commonly used for the control of lepidopteran pests. A variety of factors associated with the insect host, B. thuringiensis strain, and environment affect the wide range of susceptibilities among Lepidoptera, but the interaction of gut bacteria with these factors is not understood. To assess the contribution of gut bacteria to B. thuringiensis susceptibility across a range of Lepidoptera we examined larval mortality of six species in the presence and absence of their indigenous gut bacteria. We then assessed the effect of feeding an enteric bacterium isolated from L. dispar on larval mortality following ingestion of B. thuringiensis toxin. Results Oral administration of antibiotics reduced larval mortality due to B. thuringiensis in five of six species tested. These included Vanessa cardui (L.), Manduca sexta (L.), Pieris rapae (L.) and Heliothis virescens (F.) treated with a formulation composed of B. thuringiensis cells and toxins (DiPel), and Lymantria dispar (L.) treated with a cell-free formulation of B. thuringiensis toxin (MVPII). Antibiotics eliminated populations of gut bacteria below detectable levels in each of the insects, with the exception of H. virescens, which did not have detectable gut bacteria prior to treatment. Oral administration of the Gram-negative Enterobacter sp. NAB3, an indigenous gut resident of L. dispar, restored larval mortality in all four of the species in which antibiotics both reduced susceptibility to B. thuringiensis and eliminated gut bacteria, but not in H. virescens. In contrast, ingestion of B. thuringiensis toxin (MVPII) following antibiotic treatment

  8. Draft Genome Sequence of Leptospira interrogans Serovar Bataviae Strain LepIMR 22 Isolated from a Rodent in Johor, Malaysia

    NARCIS (Netherlands)

    Amran, Fairuz; Mohd Khalid, Mohd Khairul Nizam; Mohamad, Saharuddin; Mat Ripen, Adiratna; Ahmad, Norazah; Goris, Marga G. A.; Muhammad, Ayu Haslin; Noor Halim, Nurul Atiqah

    2016-01-01

    Leptospira interrogans serovar Bataviae was recently identified as one of the persistent Leptospira serovars in Malaysia. Here, we report the draft genome sequence of the L. interrogans serovar Bataviae strain LepIMR 22 isolated from kidney of a rodent in Johor, Malaysia

  9. Porcine response to a multidrug-resistant Salmonella enterica serovar I 4,[5],12:i:- outbreak isolate

    Science.gov (United States)

    Salmonella enterica serovar I 4,[5],12:i:- has emerged as a common nontyphoidal Salmonella serovar to cause human foodborne illness. An interesting trait of serovar I 4,[5],12:i:- is it only expresses the fliC gene for bacterial motility (i.e. monophasic), while most Salmonella strains alternately e...

  10. Draft Genome Sequence of Leptospira interrogans Serovar Bataviae Strain LepIMR 22 Isolated from a Rodent in Johor, Malaysia.

    Science.gov (United States)

    Amran, Fairuz; Mohd Khalid, Mohd Khairul Nizam; Mohamad, Saharuddin; Mat Ripen, Adiratna; Ahmad, Norazah; Goris, Marga G A; Muhammad, Ayu Haslin; Noor Halim, Nurul Atiqah

    2016-09-08

    Leptospira interrogans serovar Bataviae was recently identified as one of the persistent Leptospira serovars in Malaysia. Here, we report the draft genome sequence of the L. interrogans serovar Bataviae strain LepIMR 22 isolated from kidney of a rodent in Johor, Malaysia. Copyright © 2016 Amran et al.

  11. Side effects of Bacillus thuringiensis var. kurstaki on the hymenopterous parasitic wasp Trichogramma chilonis.

    Science.gov (United States)

    Amichot, Marcel; Curty, Christine; Benguettat-Magliano, Olivia; Gallet, Armel; Wajnberg, Eric

    2016-02-01

    Most of the detrimental effects of using conventional insecticides to control crop pests are now well identified and are nowadays major arguments for replacing such compounds by the use of biological control agents. In this respect, the bacterium Bacillus thuringiensis var. kurstaki and Trichogramma (Hymenoptera: Trichogrammatidae) parasitic wasp species are both effective against lepidopterous pests and can actually be used concomitantly. In this work, we studied the potential side effects of B. thuringiensis var. kurstaki on Trichogramma chilonis females. We first evidenced an acute toxicity of B. thuringiensis on T. chilonis. Then, after ingestion of B. thuringiensis at sublethal doses, we focused on life history traits of T. chilonis such as longevity, reproductive success and the time spent on host eggs patches. The reproductive success of T. chilonis was not modified by B. thuringiensis while a significant effect was observed on longevity and the time spent on host eggs patches. The physiological and ecological meanings of the results obtained are discussed.

  12. Persistence of Bacillus thuringiensis bioinsecticides in the gut of human-flora-associated rats

    DEFF Research Database (Denmark)

    Wilcks, Andrea; Hansen, Bjarne Munk; Hendriksen, Niels Bohse

    2006-01-01

    The capability of two bioinsecticide strains of Bacillus thuringiensis (ssp. israelensis and ssp. kurstaki) to germinate and persist in vivo in the gastrointestinal tract of human-flora-associated rats was studied. Rats were dosed either with vegetative cells or spores of the bacteria for 4...... consecutive days. In animals fed spores, B. thuringiensis cells were detected in faecal and intestinal samples of all animals, whereas vegetative cells only poorly survived the gastric passage. Heat-treatment of intestinal samples, which kills vegetative cells, revealed that B. thuringiensis spores were...... capable of germination in the gastrointestinal tract. In one animal fed spores of B. thuringiensis ssp. kurstaki, these bacteria were detected at high density (10(3)-10(4) CFU g(-1) faecal and intestinal samples) even 2 weeks after the last dosage. In the same animal, passage of B. thuringiensis ssp...

  13. Isolation and identification of some Bacillus thuringiensis strains with insecticidal activity against Ceratitis capitata

    International Nuclear Information System (INIS)

    Majdoub, Nihed

    2010-01-01

    The aims of the present work is to study the effect of toxins (delta-endotoxins), extracted from different strains of Bacillus thuringiensis on Ceratitis capitata, a devastating of citrus and fruit trees. Strains of B. thuringiensis were isolated from the mud of Sebket Sejoumi. Among 70 isolates tested, 15 showed a significant identicalness activity in which 5 isolates led to mortality rates ≥ 90 pour cent . These mortality rates are caused by endotoxins of B. thuringiensis. Analysis of proteins profiles of different isolates of B. thuringiensis revealed variability between them. The preliminary results of this study encourage us towards the characterization of the insecticidal activity produced by B. thuringiensis strains for large scale application.

  14. Prevalence and antimicrobial resistance of Salmonella serovars isolated from poultry in Ghana

    DEFF Research Database (Denmark)

    Andoh, Linda A.; Dalsgaard, Anders; Obiri-Danso, K.

    2016-01-01

    Poultry are possible sources of non-typhoidal Salmonella serovars which may cause foodborne human disease. We conducted a cross-sectional study to determine the prevalence of Salmonella serovars in egg-laying hens and broilers at the farm level and their susceptibility to antimicrobials commonly ...

  15. Physiological and molecular response of Lactuca sativa to colonization by Salmonella enterica serovar Dublin

    NARCIS (Netherlands)

    Klerks, M.M.; Gent-Pelzer, van M.P.E.; Franz, E.; Zijlstra, C.; Bruggen, van A.H.C.

    2007-01-01

    This paper describes the physiological and molecular interactions between the human-pathogenic organism Salmonella enterica serovar Dublin and the commercially available mini Roman lettuce cv. Tamburo. The association of S. enterica serovar Dublin with lettuce plants was first determined, which

  16. Salmonella enterica serovar Kentucky flagella are required for broiler skin adhesion and Caco-2 cell invasion

    Science.gov (United States)

    Nontyphoidal Salmonella strains are the main source of pathogenic bacterial contamination in the poultry industry. Recently, Salmonella enterica serovar Kentucky has been recognized as the most prominent serovar on carcasses in poultry-processing plants. Previous studies showed that flagella are one...

  17. Repeated isolation of Salmonella enterica Goverdhan, a very rare serovar, from Danish poultry surveillance samples

    DEFF Research Database (Denmark)

    Pedersen, Karl; Sørensen, Gitte; Szabo, Istvan

    2014-01-01

    We report here the appearance of a very rare serovar of Salmonella, S. enterica subsp. enterica serovar Goverdhan, in routine Salmonella surveillance samples from Danish poultry production. S. Goverdhan was found on nine occasions: in one broiler breeder farm in October 2010, four broiler farms a...

  18. Complete genome sequence of a multiple drug resistant Salmonella enterica serovar Typhi CT18

    DEFF Research Database (Denmark)

    Parkhill, J.; Dougan, G.; James, K.D.

    2001-01-01

    Salmonella enterica serovar Typhi (S. typhi) is the aetiological agent of typhoid fever, a serious invasive bacterial disease of humans with an annual global burden of approximately 16 million cases, leading to 600,000 fatalities(1). Many S. enterica serovars actively invade the mucosal surface o...... plasmid of Yersinia pestis....

  19. Development of Hamster Models for Acute and Chronic Infections with Leptospira borgpetersenii serovar Hardjo

    Science.gov (United States)

    The Golden Syrian hamster is frequently used as a small animal model to study acute leptospirosis. However, use of this small animal model to study Leptospira borgpetersenii serovar Hardjo infections has not been well documented. Cattle are the normal maintenance hosts of L. borgpetersenii serovar...

  20. Salmonella serovars from humans and other sources in Thailand, 1993-2002

    DEFF Research Database (Denmark)

    Bangtrakulnonth, A.; Pornreongwong, S.; Pulsrikarn, C.

    2004-01-01

    We serotyped 44,087 Salmonella isolates from humans and 26,148 from other sources from 1993 through 2002. The most common serovar causing human salmonellosis in Thailand was Salmonella enterica Weltevreden. Serovars causing human infections in Thailand differ from those in other countries and seem...

  1. Arbitrarily primed PCR- A rapid and simple method for typing of leptospiral serovars

    Directory of Open Access Journals (Sweden)

    Ramadass P

    2002-01-01

    Full Text Available PURPOSE: To investigate the use of arbitrarily primed polymerase chain reaction (AP-PCR for typing of leptospiral serovars. METHODS: AP-PCR was adopted for identification of laboratory strains of leptospires and leptospiral cultures at serovar level. A primer of 12 bp was used for amplifying DNA of 13 laboratory strains of leptospires as well as culture pellets of leptospires. RESULTS: Each serovar produced distinct DNA fingerprint which was characteristic for each serovar. These patterns were used for typing of 81 serum culture samples obtained from human leptospiral cases. Of these samples, 39 could be typed based on AP-PCR fingerprints belonging to serovars autumnalis, pomona, canicola, javanica, icterohaemorrhagiae, patoc and pyrogenes. These results were confirmed by RAPD fingerprinting of the DNA samples of the respective leptospiral serovars after culturing -FNx01them in EMJH media. One of the important findings of this work was that straight culture sample could be used for AP-PCR assay, without purification of DNA. By having more number of AP-PCR reference fingerprints, more serovars could be typed. CONCLUSIONS: AP-PCR technique provides great potential for simple and rapid identification of leptospires at serovar level, which could be useful in molecular epidemiological studies of leptospirosis.

  2. Characterization of a Monoclonal Antibody Directed against Salmonella enterica Serovar Typhimurium and Serovar [4,5,12:i:−] ▿

    Science.gov (United States)

    Rementeria, A.; Vivanco, A. B.; Ramirez, A.; Hernando, F. L.; Bikandi, J.; Herrera-León, S.; Echeita, A.; Garaizar, J.

    2009-01-01

    Flagellar extracts of Salmonella enterica serovars expressing phase 2 H1 antigenic complex (H:1,2, H:1,5, H:1,6, and H:1,7) and a mutant flagellin obtained by site-directed mutagenesis of the fljB gene from serovar Typhimurium at codon 218, transforming threonine to alanine, expressed in Escherichia coli (fljB218A) were used to analyze the H1 antigenic complex. Cross-reactions were detected by Western blotting and dot blotting using commercial polyclonal antibodies against the different wild-type extracts and mutant FljB218A. Therefore, we produced a monoclonal antibody (MAb), 23D4, isotyped as immunoglobulin M, against H:1,2 S. enterica serovar Typhimurium flagellin. The mutant flagellin was not recognized by this MAb. When a large number of phase 1 and phase 2 flagellin antigens of different serovars were used to characterize the 23D4 MAb, only extracts of serovars Typhimurium and [4,5,12:i:−] reacted. The protein composition of phase 1 and phase 2 extracts and highly purified H:1,2 flagellin from serovar Typhimurium strain LT2 and extract of strain 286 (serovar [4,5,12:i:−]), which reacted with the MAb, was studied. Phase 2 flagellin (FljBH:1,2) was detected in phase 1 and phase 2 flagellar heat extracts of serovar Typhimurium and was the single protein identified in all spots of purified H:1,2 flagellin. FliC, FlgK, and other proteins were detected in some immunoreactive spots and in the flagellar extract of serovar [4,5,12:i:−]. Immunoelectron microscopy of complete bacteria with 23D4 showed MAb attachment at the base of flagella, although the MAb failed to recognize the filament of flagella. Nevertheless, the results obtained by the other immunological tests (enzyme-linked immunosorbent assay, Western blotting, and dot blotting) indicate a reaction against flagellins. The epitopes could also be shared by other proteins on spots where FljB is not present, such as aminopeptidase B, isocitrate lyase, InvE, EF-TuA, enolase, DnaK, and others. In conclusion

  3. Expression of chitinase-encoding genes in Bacillus thuringiensis and toxicity of engineered B. thuringiensis subsp. aizawai toward Lymantria dispar larvae.

    Science.gov (United States)

    Lertcanawanichakul, Monthon; Wiwat, Chanpen; Bhumiratana, Amaret; Dean, Donald Harry

    2004-03-01

    Chitinase genes from Aeromonas hydrophila and Bacillus circulans No.4.1 were cloned into the plasmid pHY300PLK and designated as pHYA2 and pHYB43, respectively. Both plasmids were introduced into various strains of B. thuringiensis by electroporation. Plasmid pHYB43 was generally structurally stable, but showed lower segregrational stability than pHYA2 in B. thuringiensis subsp. aizawai when grown under nonselective conditions. The production of chitinase from B. thuringiensis subsp. aizawai harboring pHYB43 or pHYA2 could be detected after native polyacrylamide gel electrophoresis by using 4-methylumbelliferyl beta-D- N,N'- diacetylchitobioside as the substrate. Moreover, B. thuringiensis subsp. aizawai harboring pHYB43 gave 15 times higher chitinase activity than when harboring pHYA2, as determined by means of a colorimetric method using glycol chitin as the substrate. In addition, B. thuringiensis subsp. aizawai harboring pHYB43 was more toxic to gypsy moth larvae ( Lymantria dispar) than parental B. thuringiensis subsp. aizawai or its clone harboring pHYA2.

  4. Molluscicidal activity of Bacillus thuringiensis strains against Biomphalaria alexandrina snails

    Directory of Open Access Journals (Sweden)

    Amany M. Abd El-Ghany

    2017-12-01

    Full Text Available Schistosomiasis is a parasitic disease transmitted to man and different warm blooded animals by means of snails. Great effort has been made to control the transmission of the disease by many strategies. Consequently, the utilization of particular molluscicides is viewed as a standout amongst the best measures for molluscs control. Recently, microbial pathogen used as non-traditional molluscicides which have attracted significant research attention due to the increasing, worldwide development of resistance to chemical molluscicides in molluscs populations. The present work aimed to study the molluscicidal impacts of eleven isolates of Bacillus thuringiensis which were isolated from soils of six Egyptian governorates toward Biomphalaria alexandrina snails. Results showed that, B. thuringiensis provides an effective biological control agent against B. alexandrina snails. Out of the tested isolates, four isolates; Qalyubia, Asyut 1, Qena and North Sinai 2 isolates show high-level molluscicidal activity. The obtained results indicated that LC50 and LC90 values were ranged between 133.27–457.74 mg/mL and 270.32–781.05 mg/mL, respectively. The most noteworthy molluscicidal impact was displayed by Qalyubia isolate which isolated from Qalyubia governorate with mortality rate extended from 20% to100% at five treatment concentrations of 100–500 mg/mL. The LC50 and LC90 values for Qalyubia isolate were 133.27 mg/mL and 270.32 mg/mL, respectively. Keywords: Biomphalaria alexandrina, Bacillus thuringiensis, Molluscicidal activity, Biological control

  5. [Isolation of Bacillus thuringiensis IMV B-7324 fibrinolytic peptidase].

    Science.gov (United States)

    Nidialkova, N A; Matseliukh, O V; Varbanets', L D

    2012-01-01

    Fibrinolytic peptidase of Bacillus thuringiensis IMV B-7324 was isolated by ammonium sulfate fractionation, gel-filtration and ion exchange chromatography on TSK-gels--Toyopearl HW-55 and DEAE 650 (M). Fibrinolytic activity of the purified enzyme was 87.9 U/mg of protein that was 19.9 times higher compared with the supernatant cultural liquid, the yield on its activity reached 31%. The gel-filtration on Sepharose 6B and by SDS-PAGE electrophoresis demonstrated the homogeneity of the purified fibrinolytic peptidase, which molecular weight was approximately 24 kDa.

  6. Bacillus thuringiensis HD-1 Cry- : development of a safe, non-insecticidal simulant for Bacillus anthracis.

    Science.gov (United States)

    Bishop, A H; Robinson, C V

    2014-09-01

    A representative simulant for spores of Bacillus anthracis is needed for field testing. Bacillus thuringiensis is gaining recognition as a suitable organism. A strain that does not form the insecticidal, parasporal crystals that are characteristic of this species is a more accurate physical representative of B. anthracis spores. We developed noninsecticidal derivatives of two isolates of B. thuringiensis HD-1. Two plasmid-cured derivatives of B. thuringiensis HD-1, unable to make crystal toxins ('Cry(-) '), were isolated. These isolates and the existing Cry(-) strain, B. thuringiensis Al Hakam, were probed with PCR assays against the known insecticidal genes cry, vip and cyt. Their genomic DNA was sequenced to demonstrate a lack of insecticidal genes. This was confirmed by bioassays against a number of invertebrate species. Real-time PCR assays were developed to identify the B. thuringiensis HD-1 Cry(-) derivatives and an effective differential and selective medium was assessed. All three Cry(-) isolates are devoid of known insecticidal determinants. The B. thuringiensis HD-1 Cry(-) derivatives can easily be recovered from soil and identified by PCR with some selectivity. The B. thuringiensis HD-1 Cry(-) derivatives represent accurate, nongenetically manipulated simulants for B. anthracis with excellent human and environmental safety records. © 2014 Crown Copyright. Journal of Applied Microbiology © 2014 Society for Applied Microbiology This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland.

  7. Changing trends in antimicrobial resistance of Salmonella enterica serovar typhi and salmonella enterica serovar paratyphi A in Chennai

    Directory of Open Access Journals (Sweden)

    Krishnan Padma

    2009-10-01

    Full Text Available Background and Objectives: Chloramphenicol was considered the anti-microbial gold standard for typhoid treatment but, following the increasing worldwide frequency of antibiotic resistance, ciprofloxacin has been the mainstay of therapy since 1980. Recent studies have shown a shifting of susceptibility to conventional drugs like chloramphenicol, ampicillin and cotrimoxazole. The primary objective of the study was to evaluate the in vitro activity of chloramphenicol and other first-line drugs in comparison with cephalosporins and quinolones. Materials and Methods: Fifty isolates of Salmonella obtained from blood culture were subjected to serotyping at the Central Research Institute, Kasauli. Phage typing and biotyping was performed at the National Phage Typing Centre, New Delhi. Antibiotic sensitivity testing was carried out for 10 drugs by the Kirby-Bauer disc diffusion method and minimum inhibitory concentration by broth microdilution for nalidixic acid, chloramphenicol, ciprofloxacin, ceftriaxone, cefixime and ofloxacin. Multi-drug-resistant (MDR strains were checked for plasmid. Results: In the present study, 70 and 30% of the isolates were Salmonella enterica serovar typhi and paratyphi A, respectively. They were highly sensitive to chloramphenicol (86%, ampicillin (84% and cotrimoxazole (88%. Highest sensitivity was seen for cephalosporins, followed by quinolones. Seventeen/21 (81% and 100% of the Salmonella enterica serovar typhi strains belonged to E1 phage type and biotype 1, respectively. Antibiogram showed 2% of the strains to be sensitive to all the drugs tested and 12% were MDR and showed the presence of plasmids. Conclusion: The study indicates reemergence of chloramphenicol-susceptible Salmonella enterica serovar typhi and paratyphi A isolates, a significant decline in MDR strains and high resistance to nalidixic acid. E1 phage type and biotype 1 are found to be most prevalent in Chennai, India.

  8. Chemical modulators of the innate immune response alter gypsy moth larval susceptibility to Bacillus thuringiensis

    Directory of Open Access Journals (Sweden)

    Broderick Nichole A

    2010-04-01

    Full Text Available Abstract Background The gut comprises an essential barrier that protects both invertebrate and vertebrate animals from invasion by microorganisms. Disruption of the balanced relationship between indigenous gut microbiota and their host can result in gut bacteria eliciting host responses similar to those caused by invasive pathogens. For example, ingestion of Bacillus thuringiensis by larvae of some species of susceptible Lepidoptera can result in normally benign enteric bacteria exerting pathogenic effects. Results We explored the potential role of the insect immune response in mortality caused by B. thuringiensis in conjunction with gut bacteria. Two lines of evidence support such a role. First, ingestion of B. thuringiensis by gypsy moth larvae led to the depletion of their hemocytes. Second, pharmacological agents that are known to modulate innate immune responses of invertebrates and vertebrates altered larval mortality induced by B. thuringiensis. Specifically, Gram-negative peptidoglycan pre-treated with lysozyme accelerated B. thuringiensis-induced killing of larvae previously made less susceptible due to treatment with antibiotics. Conversely, several inhibitors of the innate immune response (eicosanoid inhibitors and antioxidants increased the host's survival time following ingestion of B. thuringiensis. Conclusions This study demonstrates that B. thuringiensis infection provokes changes in the cellular immune response of gypsy moth larvae. The effects of chemicals known to modulate the innate immune response of many invertebrates and vertebrates, including Lepidoptera, also indicate a role of this response in B. thuringiensis killing. Interactions among B. thuringiensis toxin, enteric bacteria, and aspects of the gypsy moth immune response may provide a novel model to decipher mechanisms of sepsis associated with bacteria of gut origin.

  9. Genome-Scale Screening and Validation of Targets for Identification of Salmonella enterica and Serovar Prediction.

    Science.gov (United States)

    Zhou, Xiujuan; Zhang, Lida; Shi, Chunlei; Fratamico, Pina M; Liu, Bin; Paoli, George C; Dan, Xianlong; Zhuang, Xiaofei; Cui, Yan; Wang, Dapeng; Shi, Xianming

    2016-03-01

    Salmonella enterica is the most common foodborne pathogen worldwide, with 2,500 recognized serovars. Detection of S. enterica and its classification into serovars are essential for food safety surveillance and clinical diagnosis. The PCR method is useful for these applications because of its rapidity and high accuracy. We obtained 412 candidate detection targets for S. enterica using a comparative genomics mining approach. Gene ontology (GO) functional enrichment analysis of these candidate targets revealed that the GO term with the largest number of unigenes with known function (38 of 177, 21.5%) was significantly involved in pathogenesis (P enterica by verification with 151 S. enterica strains and 34 non-Salmonella strains. The phylogenetic trees of verified targets were highly comparable with those of housekeeping genes, especially for differentiating S. enterica strains into serovars. The serovar prediction ability was validated by sequencing one target (S9) for 39 S. enterica strains belonging to six serovars. Identical mutation sites existed in the same serovar, and different mutation sites were found in diverse serovars. Our findings revealed that 15 verified targets can be potentially used for molecular detection, and some of them can be used for serotyping of S. enterica strains.

  10. DETERMINASI SEROVAR BAKTERI LEPTOSPIRA PADA RESERVOIR DI KABUPATEN BANYUMAS

    Directory of Open Access Journals (Sweden)

    Tri Ramadhani

    2016-05-01

    Full Text Available Leptospirosis is an infectious disease caused by pathogenic Leptospira. Leptospirosis transmitted to human through direct contact with body fluids of infected animals or indirectly through contaminated puddles . The prevalence of leptospirosis in Banyumas tends to increase for 3 years. The purpose of this study was to determine the leptospira serovar in reservoir to prove of a current infection. Surveys was conducted using single live traps for three consecutive days, determination of leptospira serovar was conducted using Microscopic Aglutination Test (MAT. Data analysis was performed by univariate and presented in tables and graphs. The results showed that the trapped animals consisted of Rattus tanezumi (70.6% and Suncus murinus (29.4% with 6.5% succsess trap. Rattus tanezumi were dominantly caught inside the house (51% than outside the house (49%. Female rats were dominantly caught (66.7% than male rats (33.3%. Suncus murinus and Rattus tanezumi shown a titer of 1/100 to be infected with L.icterohaemorrhagiae , L.javanica and L.cynopteri which are pathogenic Leptospira in humans. Efforts are needed to improve community participation in preventing tranmission of leptospirosis by avoiding contact with contaminated water and soil. For people who are risk of exposure to infected animal should wear protective clothes or footwear.

  11. ANTIBACTERIAL ACTIVITY OF SILVER NANOPARTICLES: SENSITIVITY OF DIFFERENT SALMONELLA SEROVARS

    Directory of Open Access Journals (Sweden)

    Carmen eLosasso

    2014-05-01

    Full Text Available Salmonella spp. is one of the main causes of foodborne illnesses in humans worldwide. Consequently, great interest exists in reducing its impact on human health by lowering its prevalence in the food chain. Antimicrobial formulations in the form of nanoparticles exert bactericidal action due to their enhanced reactivity resultant from their high surface/volume ratio. Silver nanoparticles (AgNPs are known to be highly toxic to Gram-negative and Gram-positive microorganisms, including multidrug resistant bacteria. However, few data concerning their success against different Salmonella serovars are available. Aims of the present study were to test the antimicrobial effectiveness of AgNPs, against Salmonella Enteritidis, Hadar and Senftenberg, and to investigate the causes of their different survival abilities from a molecular point of view.Results showed an immediate, time-limited and serovar-dependent reduction of bacterial viability. In the case of S. Senftenberg, the reduction in numbers was observed for up to 4 h of incubation in the presence of 200 mg/L of AgNPs; on the contrary, S. Enteritidis and S. Hadar resulted to be inhibited for up to 48 h. RT-PCR experiments demonstrated the constitutive expression of the plasmidic silver resistance determinant (SilB by S. Senftenberg, thus suggesting the importance of a cautious use of AgNPs.

  12. Bacillus thuringiensis subsp. israelensis and Its Dipteran-Specific Toxins

    Science.gov (United States)

    Ben-Dov, Eitan

    2014-01-01

    Bacillus thuringiensis subsp. israelensis (Bti) is the first Bacillus thuringiensis to be found and used as an effective biological control agent against larvae of many mosquito and black fly species around the world. Its larvicidal activity resides in four major (of 134, 128, 72 and 27 kDa) and at least two minor (of 78 and 29 kDa) polypeptides encoded respectively by cry4Aa, cry4Ba, cry11Aa, cyt1Aa, cry10Aa and cyt2Ba, all mapped on the 128 kb plasmid known as pBtoxis. These six δ-endotoxins form a complex parasporal crystalline body with remarkably high, specific and different toxicities to Aedes, Culex and Anopheles larvae. Cry toxins are composed of three domains (perforating domain I and receptor binding II and III) and create cation-selective channels, whereas Cyts are composed of one domain that acts as well as a detergent-like membrane perforator. Despite the low toxicities of Cyt1Aa and Cyt2Ba alone against exposed larvae, they are highly synergistic with the Cry toxins and hence their combinations prevent emergence of resistance in the targets. The lack of significant levels of resistance in field mosquito populations treated for decades with Bti-bioinsecticide suggests that this bacterium will be an effective biocontrol agent for years to come. PMID:24686769

  13. Bacillus thuringiensis subsp. israelensis and Its Dipteran-Specific Toxins

    Directory of Open Access Journals (Sweden)

    Eitan Ben-Dov

    2014-03-01

    Full Text Available Bacillus thuringiensis subsp. israelensis (Bti is the first Bacillus thuringiensis to be found and used as an effective biological control agent against larvae of many mosquito and black fly species around the world. Its larvicidal activity resides in four major (of 134, 128, 72 and 27 kDa and at least two minor (of 78 and 29 kDa polypeptides encoded respectively by cry4Aa, cry4Ba, cry11Aa, cyt1Aa, cry10Aa and cyt2Ba, all mapped on the 128 kb plasmid known as pBtoxis. These six δ-endotoxins form a complex parasporal crystalline body with remarkably high, specific and different toxicities to Aedes, Culex and Anopheles larvae. Cry toxins are composed of three domains (perforating domain I and receptor binding II and III and create cation-selective channels, whereas Cyts are composed of one domain that acts as well as a detergent-like membrane perforator. Despite the low toxicities of Cyt1Aa and Cyt2Ba alone against exposed larvae, they are highly synergistic with the Cry toxins and hence their combinations prevent emergence of resistance in the targets. The lack of significant levels of resistance in field mosquito populations treated for decades with Bti-bioinsecticide suggests that this bacterium will be an effective biocontrol agent for years to come.

  14. Dark fermentative bioconversion of glycerol to hydrogen by Bacillus thuringiensis.

    Science.gov (United States)

    Kumar, Prasun; Sharma, Rishi; Ray, Subhasree; Mehariya, Sanjeet; Patel, Sanjay K S; Lee, Jung-Kul; Kalia, Vipin C

    2015-04-01

    Biodiesel manufacturing units discharge effluents rich in glycerol. The need is to convert crude glycerol (CG) into useful products such as hydrogen (H2). Under batch culture, Bacillusthuringiensis EGU45 adapted on pure glycerol (PG, 2% v/v) resulted in an H2 yield of 0.646 mol/mol glycerol consumed on minimal media (250 mL) supplemented with 1% ammonium nitrate at 37°C over 4 days. Here, H2 constituted 67% of the total biogas. Under continuous culture, at 2 days of hydraulic retention time, B. thuringiensis immobilized on ligno-cellulosic materials (banana leaves - BL, 10% v/v) resulted in a H2 yield of 0.386 mol/mol PG consumed. On CG, the maximal H2 yield of 0.393 mol/mol feed consumed was recorded. In brief, B. thuringiensis could transform CG, on limited resources - minimal medium with sodium nitrate, by immobilizing them on cheap and easily available biowaste, which makes it a suitable candidate for H2 production on a large scale. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Identification and characterization of serovar-independent immunogens in Actinobacillus pleuropneumoniae

    DEFF Research Database (Denmark)

    Antenucci, Fabio; Fougeroux, Cyrielle; Bosse, Janine T.

    2017-01-01

    for the selection and in vitro testing of serovar-independent A. pleuropneumoniae immunogens. Potential immunogens were identified in the complete genomes of three A. pleuropneumoniae strains belonging to different serovars using the following parameters: predicted outer-membrane subcellular localization; ≤ 1 trans...... with ApfA and VacJ, could represent effective immunogens for the prevention of A. pleuropneumoniae infections in a serovar-independent manner. This hypothesis is nonetheless predictive in nature, and in vivo testing in a relevant animal model will be necessary to verify its validity....

  16. Isolation and partial characterization of a mutant of Bacillus thuringiensis producing melanin Isolamento e caracterização parcial de um mutante de Bacillus thuringiensis produtor de melanina

    Directory of Open Access Journals (Sweden)

    Gislayne T. Vilas-Bôas

    2005-09-01

    Full Text Available A mutant (407-P of Bacillus thuringiensis subsp. thuringiensis strain 407 producing a melanin was obtained after treatment with the mutagenic agent ethyl-methane-sulfonate. Several microbiological and biochemical properties of the two strains were analyzed and the results were similar. The mutant 407-P was also incorporated into non-sterilized soil samples, recovered, easily identified, and quantified, what enables its use in ecology of B. thuringiensis.Um mutante (407-P da linhagem Bacillus thuringiensis subsp. thuringiensis 407 produtor de melanina foi obtido após tratamento com o agente mutagênico etil-metano-sulfonato. Diversas propriedades microbiológicas e bioquímicas das duas linhagens foram analisadas e os resultados foram similares. O mutante 407-P foi incorporado em amostras de solo não esterilizado, recuperado, facilmente identificado e quantificado, possibilitando seu uso em estudos de ecologia de B. thuringiensis.

  17. Germination and conjugation of Bacillus thuringiensis subsp. israelensis in the intestine of gnotobiotic rats

    DEFF Research Database (Denmark)

    Wilcks, Andrea; Ørum-Smidt, Lasse; Bahl, Martin Iain

    2008-01-01

    Aims: To study the ability of Bacillus thuringiensis subsp. israelensis spores to germinate and subsequently transfer a conjugative plasmid in the intestinal tract of gnotobiotic rats. Methods and Results: Germination was studied by feeding germ-free rats with spores of a B. thuringiensis strain...... harbouring a plasmid encoding green fluorescent protein (GFP), which enabled quantification of germinated bacteria by flow cytometry. To study in vivo conjugation, germ-free rats were first associated with a B. thuringiensis recipient strain and after 1 week an isogenic donor strain harbouring...... the conjugative plasmid pXO16 was introduced. Both strains were given as spores and transfer of pXO16 was observed from the donor to the recipient strain. Conclusions: Bacillus thuringiensis is able to have a full life cycle in the intestine of gnotobiotic rats including germination of spores, several cycles...

  18. Translocation and insecticidal activity of Bacillus thuringiensis living inside of plants

    OpenAIRE

    Monnerat, Rose Gomes; Soares, Carlos Marcelo; Capdeville, Guy; Jones, Gareth; Martins, Érica Soares; Praça, Lilian; Cordeiro, Bruno Arrivabene; Braz, Shélida Vasconcelos; Dos Santos, Roseane Cavalcante; Berry, Colin

    2009-01-01

    Summary The major biological pesticide for the control of insect infestations of crops, Bacillus thuringiensis was found to be present naturally within cotton plants from fields that had never been treated with commercial formulations of this bacterium. The ability of B. thuringiensis to colonize plants as an endophyte was further established by the introduction of a strain marked by production of green fluorescent protein (GFP). After inoculation of this preparation close to the roots of cot...

  19. Molecular characterisation of multidrug-resistant Salmonella enterica serovar Typhimurium isolates from Gomel region, Belarus

    DEFF Research Database (Denmark)

    Tapalski, D.; Hendriksen, Rene S.; Hasman, Henrik

    2007-01-01

    This study describes the characterisation by pulsed-field gel electrophoresis (PFGE), multilocus variable number tandem repeat analysis (MLVA) typing and antimicrobial resistance profiles of 35 Salmonella enterica serovar Typhimurium isolates, mostly from infections in children who acquired...

  20. Multiple‐locus variable‐number tandem repeat analysis of Salmonella enterica subsp. enterica serovar Dublin

    DEFF Research Database (Denmark)

    Kjeldsen, M. K.; Torpdahl, M.; Campos, J.

    2014-01-01

    Salmonella serovar Dublin causes disease in cattle and leads to considerable production losses. In humans, severe invasive disease and high mortality rates are reported. The presently available typing methods provide insufficient discrimination within Salm. Dublin for epidemiological investigatio...

  1. Polyamines Are Required for Virulence in Salmonella enterica Serovar Typhimurium

    DEFF Research Database (Denmark)

    Jelsbak, Lotte; Thomsen, Line Elnif; Wallrodt, Inke

    2012-01-01

    Sensing and responding to environmental cues is a fundamental characteristic of bacterial physiology and virulence. Here we identify polyamines as novel environmental signals essential for virulence of Salmonella enterica serovar Typhimurium, a major intracellular pathogen and a model organism......, we show that an S. Typhimurium polyamine mutant is defective for invasion, intracellular survival, killing of the nematode Caenorhabditis elegans and systemic infection of the mouse model of typhoid fever. Virulence of the mutant could be restored by genetic complementation, and invasion...... and intracellular survival could, as well, be complemented by the addition of exogenous putrescine and spermidine to the bacterial cultures prior to infection. Interestingly, intracellular survival of the polyamine mutant was significantly enhanced above the wild type level by the addition of exogenous putrescine...

  2. Typing of Salmonella enterica serovar Saintpaul: an outbreak investigation

    DEFF Research Database (Denmark)

    Baggesen, Dorte Lau; Wegener, Henrik Caspar; Christensen, J.P.

    1996-01-01

    During the summer of 1993 an outbreak of human salmonellosis caused by Salmonella serovar Saintpaul occurred in Denmark. A total of 35 isolates originating from pigs, turkeys and imported foodstuffs, and 10 human isolates were compared following their characterization by agglutination of the O:5...... factor, antibiogram typing, plasmid profiling, ribotyping and pulsed field gel electrophoresis, in order to identify the most probable source of infection. After typing, the source of the investigated outbreak remains obscure because so far no isolates with traits of the outbreak strain have been...... recovered from production animals. Presence of the O:5 factor and absence of plasmids in human and porcine isolates pointed to pork as the source of infection, whereas human isolates and all Danish isolates from turkeys had the same ribotype, indicating that turkey was the infection source. A possible...

  3. Decreased toxicity of Bacillus thuringiensis subsp. israelensis to mosquito larvae after contact with leaf litter.

    Science.gov (United States)

    Tetreau, Guillaume; Stalinski, Renaud; Kersusan, Dylann; Veyrenc, Sylvie; David, Jean-Philippe; Reynaud, Stéphane; Després, Laurence

    2012-08-01

    Bacillus thuringiensis subsp. israelensis is a bacterium producing crystals containing Cry and Cyt proteins, which are toxic for mosquito larvae. Nothing is known about the interaction between crystal toxins and decaying leaf litter, which is a major component of several mosquito breeding sites and represents an important food source. In the present work, we investigated the behavior of B. thuringiensis subsp. israelensis toxic crystals sprayed on leaf litter. In the presence of leaf litter, a 60% decrease in the amount of Cyt toxin detectable by immunology (enzyme-linked immunosorbent assays [ELISAs]) was observed, while the respective proportions of Cry toxins were not affected. The toxicity of Cry toxins toward Aedes aegypti larvae was not affected by leaf litter, while the synergistic effect of Cyt toxins on all B. thuringiensis subsp. israelensis Cry toxins was decreased by about 20% when mixed with leaf litter. The toxicity of two commercial B. thuringiensis subsp. israelensis strains (VectoBac WG and VectoBac 12AS) and a laboratory-produced B. thuringiensis subsp. israelensis strain decreased by about 70% when mixed with leaf litter. Taken together, these results suggest that Cyt toxins interact with leaf litter, resulting in a decreased toxicity of B. thuringiensis subsp. israelensis in litter-rich environments and thereby dramatically reducing the efficiency of mosquitocidal treatments.

  4. Persistence of Bacillus thuringiensis subsp. kurstaki in Urban Environments following Spraying▿†‡

    Science.gov (United States)

    Van Cuyk, Sheila; Deshpande, Alina; Hollander, Attelia; Duval, Nathan; Ticknor, Lawrence; Layshock, Julie; Gallegos-Graves, LaVerne; Omberg, Kristin M.

    2011-01-01

    Bacillus thuringiensis subsp. kurstaki is applied extensively in North America to control the gypsy moth, Lymantria dispar. Since B. thuringiensis subsp. kurstaki shares many physical and biological properties with Bacillus anthracis, it is a reasonable surrogate for biodefense studies. A key question in biodefense is how long a biothreat agent will persist in the environment. There is some information in the literature on the persistence of Bacillus anthracis in laboratories and historical testing areas and for Bacillus thuringiensis in agricultural settings, but there is no information on the persistence of Bacillus spp. in the type of environment that would be encountered in a city or on a military installation. Since it is not feasible to release B. anthracis in a developed area, the controlled release of B. thuringiensis subsp. kurstaki for pest control was used to gain insight into the potential persistence of Bacillus spp. in outdoor urban environments. Persistence was evaluated in two locations: Fairfax County, VA, and Seattle, WA. Environmental samples were collected from multiple matrices and evaluated for the presence of viable B. thuringiensis subsp. kurstaki at times ranging from less than 1 day to 4 years after spraying. Real-time PCR and culture were used for analysis. B. thuringiensis subsp. kurstaki was found to persist in urban environments for at least 4 years. It was most frequently detected in soils and less frequently detected in wipes, grass, foliage, and water. The collective results indicate that certain species of Bacillus may persist for years following their dispersal in urban environments. PMID:21926205

  5. Decreased Toxicity of Bacillus thuringiensis subsp. israelensis to Mosquito Larvae after Contact with Leaf Litter

    Science.gov (United States)

    Stalinski, Renaud; Kersusan, Dylann; Veyrenc, Sylvie; David, Jean-Philippe; Reynaud, Stéphane; Després, Laurence

    2012-01-01

    Bacillus thuringiensis subsp. israelensis is a bacterium producing crystals containing Cry and Cyt proteins, which are toxic for mosquito larvae. Nothing is known about the interaction between crystal toxins and decaying leaf litter, which is a major component of several mosquito breeding sites and represents an important food source. In the present work, we investigated the behavior of B. thuringiensis subsp. israelensis toxic crystals sprayed on leaf litter. In the presence of leaf litter, a 60% decrease in the amount of Cyt toxin detectable by immunology (enzyme-linked immunosorbent assays [ELISAs]) was observed, while the respective proportions of Cry toxins were not affected. The toxicity of Cry toxins toward Aedes aegypti larvae was not affected by leaf litter, while the synergistic effect of Cyt toxins on all B. thuringiensis subsp. israelensis Cry toxins was decreased by about 20% when mixed with leaf litter. The toxicity of two commercial B. thuringiensis subsp. israelensis strains (VectoBac WG and VectoBac 12AS) and a laboratory-produced B. thuringiensis subsp. israelensis strain decreased by about 70% when mixed with leaf litter. Taken together, these results suggest that Cyt toxins interact with leaf litter, resulting in a decreased toxicity of B. thuringiensis subsp. israelensis in litter-rich environments and thereby dramatically reducing the efficiency of mosquitocidal treatments. PMID:22610426

  6. Chlamydia trachomatis Serovar Distribution and Neisseria gonorrhoeae Coinfection in Male Patients with Urethritis in Greece▿

    Science.gov (United States)

    Papadogeorgakis, Helen; Pittaras, Theodore E.; Papaparaskevas, Joseph; Pitiriga, Vassiliki; Katsambas, Andreas; Tsakris, Athanassios

    2010-01-01

    The distribution of Chlamydia trachomatis serovars and Neisseria gonorrhoeae coinfection was studied in a group of 100 C. trachomatis-positive males with urethritis in Greece. The serovar distribution revealed that apart from the predominant worldwide types E and F, the relatively uncommon type G is also prevalent. Gonococcal coinfection was frequent (30%) and was associated with genovariant Ja (75%, P = 0.008). PMID:20357220

  7. Molecular Characterization of Multidrug-Resistant Salmonella enterica subsp. enterica Serovar Typhimurium Isolates from Swine

    OpenAIRE

    Gebreyes, Wondwossen Abebe; Altier, Craig

    2002-01-01

    As part of a longitudinal study of antimicrobial resistance among salmonellae isolated from swine, we studied 484 Salmonella enterica subsp. enterica serovar Typhimurium (including serovar Typhimurium var. Copenhagen) isolates. We found two common pentaresistant phenotypes. The first was resistance to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (the AmCmStSuTe phenotype; 36.2% of all isolates), mainly of the definitive type 104 (DT104) phage type (180 of 187 ...

  8. Epidemiological investigation of Salmonella enterica serovar Kedougou in Thailand.

    Science.gov (United States)

    Pornruangwong, Srirat; Hendriksen, Rene S; Pulsrikarn, Chaiwat; Bangstrakulnonth, Aroon; Mikoleit, Matthew; Davies, Rob H; Aarestrup, Frank M; Garcia-Migura, Lourdes

    2011-02-01

    Salmonella enterica serovar Kedougou is among the top 10 serovars reported in northern Thailand. The objective of this study was to identify risk factors associated with Salmonella Kedougou infection in Thailand and to compare the molecular types and antimicrobial resistance with Salmonella Kedougou isolates of human origin from United States and of animal origin from the United Kingdom. Data from 13,976 Salmonella infections of which 253 were Salmonella Kedougou collected in Thailand between 2002 and 2008 were analyzed by logistic regression. Antimicrobial susceptibility testing and pulsed-field gel electrophoresis (PFGE) were performed on selected Salmonella Kedougou strains causing infections in Thailand (n = 66), and compared to isolates from the United States (n = 5) and the United Kingdom (n = 20). Logistic analysis revealed season (hot/dry; p = 0.023), region (northern Thailand; p Thailand were resistant to third-generation cephalosporins: two harbored bla(CTX-M-63) and one bla(CMY-2). PFGE revealed 45 unique clusters. Isolates obtained from humans in Thailand and the United States presented identical PFGE profiles suggesting a travel association, whereas the majority of the animal isolates from United Kingdom clustered separately. This study reveals Salmonella Kedougou as a major cause of human infections in northern Thailand especially during the hot period and suggests a global spread probably due to travel. The clonal types causing infections in humans differed from those observed in animals in United Kingdom, which suggests the absence of an epidemiological link and could suggest differences in virulence. The high frequency of antimicrobial resistance, including emergence of resistance to fluoroquinolones and third-generation cephalosporins, might pose problems for treatment of infections.

  9. Cross neutralizing antibodies in hamsters vaccinated with leptospiral bacterins produced with three serovars of serogroup Sejroe

    Directory of Open Access Journals (Sweden)

    Rosana Tabata

    2002-09-01

    Full Text Available Three leptospiral bacterins, produced with different serovars of Serogroup Sejroe, namely the hardjo (bacterin A, wolffi (bacterin B and guaricura (bacterin C, were evaluated in male hamsters (Mesocricetus auratus by comparing the agglutinating and neutralizing antibodies titers using microscopic agglutination (MAT and in vitro growth inhibition (GIT tests. The immunization schedule was based on two 1.0 mL doses of non-diluted formalininactivated whole culture bacterin given through subcutaneous route with 10-day interval. The challenge was performed ten days after the second vaccine dose, when the animals were inoculated with 0.2 mL of non-inactivated cultures of each serovar through intraperitoneal route. On the 21st post-challenge day (PCD, all animals were bled and their sera were joined in pools (n=8 and tested by MAT and GIT. All vaccinated and control animals presented no clinical signs of leptospirosis after the challenge, but the serovar guaricura was isolated from the kidneys of control animals on the 21st PCD. The MAT results showed cross agglutinins between serovars hardjo and wolffi, and between wolffi and guaricura. The GIT results revealed the presence of cross neutralizing antibodies between serovars wolffi or guaricura against hardjo, wolffi and guaricura. It was found that the tested strain of serovar hardjo did not produce detectable levels of neutralizing antibodies, indicating its poor immunogenicity.

  10. Presence of antibodies against Leptospira serovars in Chaetophractus villosus (Mammalia, Dasypodidae, La Pampa province, Argentina

    Directory of Open Access Journals (Sweden)

    Marta S Kin

    2015-03-01

    Full Text Available Leptospirosis is a zoonosis of worldwide distribution. The aim of this study was to examine the presence of antibodies against 21 Leptospira reactive serovars in Chaetophractus villosus in La Pampa province, Argentina, using the microscopic agglutination test (MAT. Pathologic changes compatible with leptospirosis and in situ detection of the agent by immunohistochemistry were studied in 24 and 3 individuals respectively. Only 35/150 (23.3% serum samples had antibodies against Leptospira sp. Six percent of the samples reacted with serovar Canicola, 4.7% with serovar Castellonis, 1.3% with serovar Icterohemorrhagieae and 0.7% with serovar Hardjo. Sixteen (10.6% serum samples agglutinated with Castellonis-Icterohemorrhagiae and Canicola-Castellonis serovars, both with 4.7%, and Canicola-Hardjo and Castellonis-Canicola-Icterohemorrhagiae both with 0.6%. Fourteen animals had variable degrees of lesions, which were more severe in animals with higher serological titers (3200, and Leptospira sp. was detected in 3 animals by immunohistochemistry. These results represent the first record of the presence of Leptospira in C. villosus in La Pampa.

  11. Transformation of sexually transmitted infection-causing serovars of chlamydia trachomatis using Blasticidin for selection.

    Directory of Open Access Journals (Sweden)

    Honglei Ding

    Full Text Available Plasmid-free Chlamydia trachomatis serovar L2 organisms have been transformed with chlamydial plasmid-based shuttle vectors pGFP::SW2 and pBRCT using β-lactamase as a selectable marker. However, the recommendation of amoxicillin, a β-lactam antibiotics, as one of the choices for treating pregnant women with cervicitis due to C. trachomatis infection has made the existing shuttle vectors unsuitable for transforming sexually transmitted infection (STI-causing serovars of C. trachomatis. Thus, in the current study, we modified the pGFP::SW2 plasmid by fusing a blasticidin S deaminase gene to the GFP gene to establish blasticidin resistance as a selectable marker and replacing the β-lactamase gene with the Sh ble gene to eliminate the penicillin resistance. The new vector termed pGFPBSD/Z::SW2 was used for transforming plasmid-free C. trachomatis serovar D organisms. Using blasticidin for selection, stable transformants were obtained. The GFP-BSD fusion protein was detected in cultures infected with the pGFPBSD/Z::SW2-trasnformed serovar D organisms. The transformation restored the plasmid property to the plasmid-free serovar D organisms. Thus, we have successfully modified the pGFP::SW2 transformation system for studying the biology and pathogenesis of other STI-causing serovars of C. trachomatis.

  12. Identification of Leptospira serovars by RFLP of the RNA polymerase beta subunit gene (rpoB).

    Science.gov (United States)

    Jung, Lenice Roteia Cardoso; Bomfim, Maria Rosa Quaresma; Kroon, Erna Geessien; Nunes, Álvaro Cantini

    2015-06-01

    Leptospires are usually classified by methods based on DNA-DNA hybridization and the conventional cross-agglutination absorption test, which uses polyclonal antibodies against lipopolysaccharides. In this study, the amplification of the rpoB gene, which encodes the beta-subunit of RNA polymerase, was used as an alternative tool to identify Leptospira. DNA extracts from sixty-eight serovars were obtained, and the hypervariable region located between 1990 and 2500-bp in the rpoB gene was amplified by polymerase chain reaction (PCR). The 600-bp amplicons of the rpoB gene were digested with the restriction endonucleases TaqI, Tru1I, Sau3AI and MslI, and the restriction fragments were separated by 6% polyacrylamide gel electrophoresis. Thirty-five fragment patters were obtained from the combined data of restriction fragment length polymorphism (PCR-RFLP) analysis and used to infer the phylogenetic relationships among the Leptospira species and serovars. The species assignments obtained were in full agreement with the established taxonomic classifications. Twenty-two serovars were effectively identified based on differences in their molecular profiles. However, the other 46 serovars remained clustered in groups that included more than one serovar of different species. This study demonstrates the value of RFLP analysis of PCR-amplified rpoB as an initial method for identifying Leptospira species and serovars.

  13. Presence of antibodies against Leptospira serovars in Chaetophractus villosus (Mammalia, Dasypodidae), La Pampa province, Argentina.

    Science.gov (United States)

    Kin, Marta S; Brihuega, Bibiana; Fort, Marcelo; Delgado, Fernando; Bedotti, Daniel; Casanave, Emma B

    2015-01-01

    Leptospirosis is a zoonosis of worldwide distribution. The aim of this study was to examine the presence of antibodies against 21 Leptospira reactive serovars in Chaetophractus villosus in La Pampa province, Argentina, using the microscopic agglutination test (MAT). Pathologic changes compatible with leptospirosis and in situ detection of the agent by immunohistochemistry were studied in 24 and 3 individuals respectively. Only 35/150 (23.3%) serum samples had antibodies against Leptospira sp. Six percent of the samples reacted with serovar Canicola, 4.7% with serovar Castellonis, 1.3% with serovar Icterohemorrhagieae and 0.7% with serovar Hardjo. Sixteen (10.6%) serum samples agglutinated with Castellonis-Icterohemorrhagiae and Canicola-Castellonis serovars, both with 4.7%, and Canicola-Hardjo and Castellonis-Canicola-Icterohemorrhagiae both with 0.6%. Fourteen animals had variable degrees of lesions, which were more severe in animals with higher serological titers (3200), and Leptospira sp. was detected in 3 animals by immunohistochemistry. These results represent the first record of the presence of Leptospira in C. villosus in La Pampa. Copyright © 2015 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. Identification of Leptospira serovars by RFLP of the RNA polymerase beta subunit gene (rpoB

    Directory of Open Access Journals (Sweden)

    Lenice Roteia Cardoso Jung

    2015-06-01

    Full Text Available Leptospires are usually classified by methods based on DNA-DNA hybridization and the conventional cross-agglutination absorption test, which uses polyclonal antibodies against lipopolysaccharides. In this study, the amplification of the rpoB gene, which encodes the beta-subunit of RNA polymerase, was used as an alternative tool to identify Leptospira. DNA extracts from sixty-eight serovars were obtained, and the hypervariable region located between 1990 and 2500-bp in the rpoB gene was amplified by polymerase chain reaction (PCR. The 600-bp amplicons of the rpoB gene were digested with the restriction endonucleases TaqI, Tru1I, Sau3AI and MslI, and the restriction fragments were separated by 6% polyacrylamide gel electrophoresis. Thirty-five fragment patters were obtained from the combined data of restriction fragment length polymorphism (PCR-RFLP analysis and used to infer the phylogenetic relationships among the Leptospira species and serovars. The species assignments obtained were in full agreement with the established taxonomic classifications. Twenty-two serovars were effectively identified based on differences in their molecular profiles. However, the other 46 serovars remained clustered in groups that included more than one serovar of different species. This study demonstrates the value of RFLP analysis of PCR-amplified rpoB as an initial method for identifying Leptospira species and serovars.

  15. Improvement of Bacillus thuringiensis bacteriocin production through culture conditions optimization.

    Science.gov (United States)

    Kamoun, Fakher; Zouari, Nabil; Saadaoui, Imen; Jaoua, Samir

    2009-01-01

    BUPM4 is a Bacillus thuringiensis subsp. kurstaki strain, isolated from Tunisian soil, producing an original bacteriocin named Bacthuricin F4. The optimization of the latter production conditions was carried out under several physicochemical conditions. It was found that the highest bacteriocin activity was reached at low aeration while bacteriocin synthesis yields were strongly reduced at higher ones. A balance between growth and bacteriocin synthesis, both highly dependent on aeration, was taken into account for the overproduction of bacteriocin. Both glucose and glycerol were shown to be necessary for Bacthuricin F4 maximal synthesis. In addition, the optimal carbon/nitrogen ratio for bacteriocin production is 9. In such optimal conditions, more than 4-fold greater bacteriocin production was obtained than when using TSB medium.

  16. Evaluation of a new formulation of Bacillus thuringiensis israelensis

    Directory of Open Access Journals (Sweden)

    J. Lopes

    Full Text Available The aim of this study was to determine the potency (ITU and efficacy of a liquid formulation of Bacillus thuringiensis israelensis developed by the State University of Londrina named BioUel, against early fourth instar larvae of Aedes aegypti and Culex quinquefasciatus. The ITU/mg of BioUel was 960, the LC50 was of 0.271 (± 0.39 ppm, and the LC95 was 0.634 (± 0.099 ppm, in larvae of C. quinquefasciatus. In A. aegypti larvae, LC50 was 0.332 (± 0.042 ppm and LC95 was 0.694 (± 0.073 ppm. The ITU level of BioUel and its control results were similar to most commercial products tested. Stability was of approximately 90 days, which allows for local production.

  17. Presence survival spores of Bacillus thuringiensis varieties in grain warehouse

    Directory of Open Access Journals (Sweden)

    Sánchez-Yáñez Juan Manuel

    2016-08-01

    Full Text Available Genus Bacillus thuringiensis (Bt synthesized spores and crystals toxic to pest-insects in agriculture. Bt is comospolitan then possible to isolate some subspecies or varieties from warehouse. The aims of study were: i to isolate Bt varieties from grain at werehouse ii to evaluate Bt toxicity on Spodoptera frugiperda and Shit-ophilus zeamaisese iii to analyze Bt spores persistence in Zea mays grains at werehouse compared to same Bt on grains exposed to sun radiation. Results showed that at werehouse were recovered more than one variety of Bt spores. According to each isolate Bt1 o Bt2 were toxic to S. frugiperda or S. zeamaisese. One those Bt belong to var morrisoni. At werehouse these spores on Z. mays grains surviving more time, while the same spores exposed to boicide sun radiation they died.

  18. Nanoscale imaging of Bacillus thuringiensis flagella using atomic force microscopy

    Science.gov (United States)

    Gillis, Annika; Dupres, Vincent; Delestrait, Guillaume; Mahillon, Jacques; Dufrêne, Yves F.

    2012-02-01

    Because bacterial flagella play essential roles in various processes (motility, adhesion, host interactions, secretion), studying their expression in relation to function is an important challenge. Here, we use atomic force microscopy (AFM) to gain insight into the nanoscale surface properties of two wild-type and four mutant strains of Bacillus thuringiensis exhibiting various levels of flagellation. We show that, unlike AFM in liquid, AFM in air is a simple and reliable approach to observe the morphological details of the bacteria, and to quantify the density and dimensions of their flagella. We found that the amount of flagella expressed by the six strains, as observed at the nanoscale, correlates with their microscopic swarming motility. These observations provide novel information on flagella expression in Gram-positive bacteria and demonstrate the power of AFM in genetic studies for the fast assessment of the phenotypic characteristics of bacterial strains altered in cell surface appendages.Because bacterial flagella play essential roles in various processes (motility, adhesion, host interactions, secretion), studying their expression in relation to function is an important challenge. Here, we use atomic force microscopy (AFM) to gain insight into the nanoscale surface properties of two wild-type and four mutant strains of Bacillus thuringiensis exhibiting various levels of flagellation. We show that, unlike AFM in liquid, AFM in air is a simple and reliable approach to observe the morphological details of the bacteria, and to quantify the density and dimensions of their flagella. We found that the amount of flagella expressed by the six strains, as observed at the nanoscale, correlates with their microscopic swarming motility. These observations provide novel information on flagella expression in Gram-positive bacteria and demonstrate the power of AFM in genetic studies for the fast assessment of the phenotypic characteristics of bacterial strains altered in

  19. How Quorum Sensing Connects Sporulation to Necrotrophism in Bacillus thuringiensis.

    Directory of Open Access Journals (Sweden)

    Stéphane Perchat

    2016-08-01

    Full Text Available Bacteria use quorum sensing to coordinate adaptation properties, cell fate or commitment to sporulation. The infectious cycle of Bacillus thuringiensis in the insect host is a powerful model to investigate the role of quorum sensing in natural conditions. It is tuned by communication systems regulators belonging to the RNPP family and directly regulated by re-internalized signaling peptides. One such RNPP regulator, NprR, acts in the presence of its cognate signaling peptide NprX as a transcription factor, regulating a set of genes involved in the survival of these bacteria in the insect cadaver. Here, we demonstrate that, in the absence of NprX and independently of its transcriptional activator function, NprR negatively controls sporulation. NprR inhibits expression of Spo0A-regulated genes by preventing the KinA-dependent phosphorylation of the phosphotransferase Spo0F, thus delaying initiation of the sporulation process. This NprR function displays striking similarities with the Rap proteins, which also belong to the RNPP family, but are devoid of DNA-binding domain and indirectly control gene expression via protein-protein interactions in Bacilli. Conservation of the Rap residues directly interacting with Spo0F further suggests a common inhibition of the sporulation phosphorelay. The crystal structure of apo NprR confirms that NprR displays a highly flexible Rap-like structure. We propose a molecular regulatory mechanism in which key residues of the bifunctional regulator NprR are directly and alternatively involved in its two functions. NprX binding switches NprR from a dimeric inhibitor of sporulation to a tetrameric transcriptional activator involved in the necrotrophic lifestyle of B. thuringiensis. NprR thus tightly coordinates sporulation and necrotrophism, ensuring survival and dissemination of the bacteria during host infection.

  20. Pseudogene accumulation in the evolutionary histories of Salmonella enterica serovars Paratyphi A and Typhi

    Directory of Open Access Journals (Sweden)

    White Brian

    2009-01-01

    Full Text Available Abstract Background Of the > 2000 serovars of Salmonella enterica subspecies I, most cause self-limiting gastrointestinal disease in a wide range of mammalian hosts. However, S. enterica serovars Typhi and Paratyphi A are restricted to the human host and cause the similar systemic diseases typhoid and paratyphoid fever. Genome sequence similarity between Paratyphi A and Typhi has been attributed to convergent evolution via relatively recent recombination of a quarter of their genomes. The accumulation of pseudogenes is a key feature of these and other host-adapted pathogens, and overlapping pseudogene complements are evident in Paratyphi A and Typhi. Results We report the 4.5 Mbp genome of a clinical isolate of Paratyphi A, strain AKU_12601, completely sequenced using capillary techniques and subsequently checked using Illumina/Solexa resequencing. Comparison with the published genome of Paratyphi A ATCC9150 revealed the two are collinear and highly similar, with 188 single nucleotide polymorphisms and 39 insertions/deletions. A comparative analysis of pseudogene complements of these and two finished Typhi genomes (CT18, Ty2 identified several pseudogenes that had been overlooked in prior genome annotations of one or both serovars, and identified 66 pseudogenes shared between serovars. By determining whether each shared and serovar-specific pseudogene had been recombined between Paratyphi A and Typhi, we found evidence that most pseudogenes have accumulated after the recombination between serovars. We also divided pseudogenes into relative-time groups: ancestral pseudogenes inherited from a common ancestor, pseudogenes recombined between serovars which likely arose between initial divergence and later recombination, serovar-specific pseudogenes arising after recombination but prior to the last evolutionary bottlenecks in each population, and more recent strain-specific pseudogenes. Conclusion Recombination and pseudogene-formation have been

  1. 40 CFR 174.518 - Bacillus thuringiensis Cry3Bb1 protein in corn; 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 thuringiensis Cry3Bb1 protein... PLANT-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.518 Bacillus thuringiensis Cry3Bb1 protein in corn; exemption from the requirement of a tolerance. Residues of Bacillus thuringiensis...

  2. Toxicity studies for indigenous Bacillus thuringiensis isolates from Malang City, East Java on Aedes aegypti larvae.

    Science.gov (United States)

    Gama, Zulfaidah Penata; Nakagoshi, Nobukazu; Suharjono; Setyowati, Faridah

    2013-02-01

    To investigate the toxicity of indigenous Bacillus thuringiensis (B. thuringiensis)isolates from Malang City for controlling Aedes aegypti (Ae. aegypti) larvae. Soil samples were taken from Purwantoro and Sawojajar sub-districts. Bacterial isolation was performed using B. thuringiensis selective media. Phenotypic characteristics of the isolates were obtained with the simple matching method. The growth and prevalence of spores were determined by the Total Plate Count method, and toxicity tests were also performed on the third instar larval stage of Ae. aegypti. The percentage of larval mortality was analysed using probit regression. The LC50 was analysed by ANOVA, and the Tukey HSD interval was 95%. Among the 33 selected bacterial isolates, six were obtained (PWR4-31, PWR4-32, SWJ4-2b, SWJ4-4b, SWJ-4k and SWJ5-1) that had a similar phenotype to reference B. thuringiensis. Based on the dendrogram, all of the bacterial isolates were 71% similar. Three isolates that had a higher prevalence of reference B. thuringiensis were PWR4-32, SWJ4-4b and SW5-1, of which the spore prevalence was 52.44%, 23.59%, 34.46%, respectively. These three indigenous isolates from Malang City successfully killed Ae. aegypti larvae. The PWR4-32 isolates were the most effective at killing the larvae. Six indigenous B. thuringiensis isolates among the 33 bacterial isolates found in the Sawojajar and Purwantoro sub-districts were toxic to the third instar larvae of Ae. aegypti. The PWR4-32 isolates were identical to the reference B. thuringiensis and had 88% phenotype similarity. The PWR4-32 isolates had the highest spore prevalence (52.44%), and the early stationary phase occurred at 36 h. The PWR4-32 isolates were the most effective at killing Ae. aegypti larvae (LC50-72 h=2.3×10(8) cells/mL).

  3. A Bacillus thuringiensis S-Layer Protein Involved in Toxicity against Epilachna varivestis (Coleoptera: Coccinellidae)

    Science.gov (United States)

    Peña, Guadalupe; Miranda-Rios, Juan; de la Riva, Gustavo; Pardo-López, Liliana; Soberón, Mario; Bravo, Alejandra

    2006-01-01

    The use of Bacillus thuringiensis as a biopesticide is a viable alternative for insect control since the insecticidal Cry proteins produced by these bacteria are highly specific; harmless to humans, vertebrates, and plants; and completely biodegradable. In addition to Cry proteins, B. thuringiensis produces a number of extracellular compounds, including S-layer proteins (SLP), that contribute to virulence. The S layer is an ordered structure representing a proteinaceous paracrystalline array which completely covers the surfaces of many pathogenic bacteria. In this work, we report the identification of an S-layer protein by the screening of B. thuringiensis strains for activity against the coleopteran pest Epilachna varivestis (Mexican bean beetle; Coleoptera: Coccinellidae). We screened two B. thuringiensis strain collections containing unidentified Cry proteins and also strains isolated from dead insects. Some of the B. thuringiensis strains assayed against E. varivestis showed moderate toxicity. However, a B. thuringiensis strain (GP1) that was isolated from a dead insect showed a remarkably high insecticidal activity. The parasporal crystal produced by the GP1 strain was purified and shown to have insecticidal activity against E. varivestis but not against the lepidopteran Manduca sexta or Spodoptera frugiperda or against the dipteran Aedes aegypti. The gene encoding this protein was cloned and sequenced. It corresponded to an S-layer protein highly similar to previously described SLP in Bacillus anthracis (EA1) and Bacillus licheniformis (OlpA). The phylogenetic relationships among SLP from different bacteria showed that these proteins from Bacillus cereus, Bacillus sphaericus, B. anthracis, B. licheniformis, and B. thuringiensis are arranged in the same main group, suggesting similar origins. This is the first report that demonstrates that an S-layer protein is directly involved in toxicity to a coleopteran pest. PMID:16391064

  4. Analysis of Bacillus thuringiensis Population Dynamics and Its Interaction With Pseudomonas fluorescens in Soil

    Science.gov (United States)

    Rojas-Ruiz, Norma Elena; Sansinenea-Royano, Estibaliz; Cedillo-Ramirez, Maria Lilia; Marsch-Moreno, Rodolfo; Sanchez-Alonso, Patricia; Vazquez-Cruz, Candelario

    2015-01-01

    Background: Bacillus thuringiensis is the most successful biological control agent, however, studies so far have shown that B. thuringiensis is very sensitive to environmental factors such as soil moisture and pH. Ultraviolet light from the sun had been considered as the main limiting factor for its persistence in soil and it has recently been shown that the antagonism exerted by other native soil organisms, such as Pseudomonas fluorescens, is a determining factor in the persistence of this bacterium under in vitro culture conditions. Objectives: The aim of the present investigation was to analyze the population dynamics of B. thuringiensis and its interaction with P. fluorescens using microbiological and molecular methods in soil, under different conditions, and to determinate the effect of nutrients and moisture on its interaction. Materials and Methods: The monitoring was performed by microbiological methods, such as viable count of bacteria, and molecular methods such as Polymerase Chain Reaction (PCR) and hybridization, using the direct extraction of DNA from populations of inoculated soil. Results: The analysis of the interaction between B. thuringiensis and P. fluorescens in soil indicated that the disappearance of B. thuringiensis IPS82 is not dependent on the moisture but the composition of nutrients that may be affecting the secretion of toxic compounds in the environment of P. fluorescens. The results showed that the recovered cells were mostly spores and not vegetative cells in all proved treatments. The molecular methods were effective for monitoring bacterial population inoculated in soil. Conclusions: Bacillus thuringiensis is very sensitive to the interaction of P. fluorescens, however is capable to survive in soil due to its capacity of sporulate. Some of the cells in the form of spores germinated and folded slightly and remained in a constant cycle of sporulation and germination. This confirms that B. thuringiensis IPS82 can germinate, grow and

  5. Streptomycin Induced Stress Response in Salmonella enterica Serovar Typhimurium Shows Distinct Colony Scatter Signature.

    Science.gov (United States)

    Singh, Atul K; Drolia, Rishi; Bai, Xingjian; Bhunia, Arun K

    2015-01-01

    We investigated the streptomycin-induced stress response in Salmonella enterica serovars with a laser optical sensor, BARDOT (bacterial rapid detection using optical scattering technology). Initially, the top 20 S. enterica serovars were screened for their response to streptomycin at 100 μg/mL. All, but four S. enterica serovars were resistant to streptomycin. The MIC of streptomycin-sensitive serovars (Enteritidis, Muenchen, Mississippi, and Schwarzengrund) varied from 12.5 to 50 μg/mL, while streptomycin-resistant serovar (Typhimurium) from 125-250 μg/mL. Two streptomycin-sensitive serovars (Enteritidis and Mississippi) were grown on brain heart infusion (BHI) agar plates containing sub-inhibitory concentration of streptomycin (1.25-5 μg/mL) and a streptomycin-resistant serovar (Typhimurium) was grown on BHI containing 25-50 μg/mL of streptomycin and the colonies (1.2 ± 0.1 mm diameter) were scanned using BARDOT. Data show substantial qualitative and quantitative differences in the colony scatter patterns of Salmonella grown in the presence of streptomycin than the colonies grown in absence of antibiotic. Mass-spectrometry identified overexpression of chaperonin GroEL, which possibly contributed to the observed differences in the colony scatter patterns. Quantitative RT-PCR and immunoassay confirmed streptomycin-induced GroEL expression while, aminoglycoside adenylyltransferase (aadA), aminoglycoside efflux pump (aep), multidrug resistance subunit acrA, and ribosomal protein S12 (rpsL), involved in streptomycin resistance, were unaltered. The study highlights suitability of the BARDOT as a non-invasive, label-free tool for investigating stress response in Salmonella in conjunction with the molecular and immunoassay methods.

  6. Evaluation of the use of selective PCR amplification of LPS biosynthesis genes for molecular typing of leptospira at the serovar level

    NARCIS (Netherlands)

    Bezerra da Silva, Josefa; Carvalho, Eneas; Hartskeerl, Rudy A.; Ho, Paulo L.

    2011-01-01

    Leptospirosis is an important epidemic zoonosis worldwide. Currently, there are more than 250 Leptospira pathogenic serovars known that can potentially infect humans. Conventional classification of leptospires with the serovar as the basic taxon, based on serological recognition of

  7. Evaluation of hemodynamic significance of coronary fistulae. Diagnostic integration between coronary angiography and stress/rest myocardial scintigraphy; Valutazione del significato emodinamico di fistole coronariche artero-venose. Integrazione diagnostica tra angiografia coronarica e scintigrafia miocardica a riposo e sotto sforzo

    Energy Technology Data Exchange (ETDEWEB)

    Rubini, G.; Sebastiani, M. [Bari Univ., Bari (Italy). Cattedra di Medicina Nucleare; Ettorre, G. C. [Foggia Univ., Foggia (Italy). Cattedra di Radiologia; Bovenzi, F. [Ospedale Policlinico, Unita' Operativa di Cardiologia, Bari (Italy)

    2000-12-01

    'angiografia coronarica e con la tomografia con emissione di fotone singolo utilizzando il {sup 99m}Tecnezio- sestamibi come radiofarmaco indicatore della perfusione miocardica a riposo e sotto sforzo per la valutazione del significato emodinamico delle fistole coronariche arterovenose. Le fistole coronariche sono state riconosciute in 9 pazienti mediante angiografia coronarica. Tutti i pazienti sono stati sottoposti a esame obiettivo, ecocardiografia transtoracica, elettrocardiogramma da sforzo e la tomografia ad emissione di fotone singolo per la valutazione della perfusione miocardica a riposo e sotto sforzo. Con la tomografia con emissione di fotone singolo per la valutazione della perfusione miocardica a riposo e sotto sforzo e con l'elettrocardiogramma per la valutazione della perfusione a riposo e sotto sforzo con l'elettrocardiogramma da sforzo sono stati evidenziati segni di ischemia miocardica indotta dallo sforzo in 2 pazienti. (abstract truncated)

  8. Population Structure of Salmonella enterica Serovar 4,[5],12:b:− Strains and Likely Sources of Human Infection

    Science.gov (United States)

    Toboldt, Anne; Tietze, Erhard; Helmuth, Reiner; Junker, Ernst; Fruth, Angelika

    2013-01-01

    Salmonella enterica serovar 4,[5],12:b:− is a monophasic serovar not able to express the second-phase flagellar antigen (H2 antigen). In Germany, the serovar is occasionally isolated from poultry, reptiles, fish, food, and humans. In this study, a selection of 67 epidemiologically unrelated Salmonella enterica serovar 4,[5],12:b:− strains isolated in Germany between 2000 and 2011 from the environment, animal, food, and humans was investigated by phenotypic and genotypic methods to better understand the population structure and to identify potential sources of human infections. Strains of this monophasic serovar were highly diverse. Within the 67 strains analyzed, we identified 52 different pulsed-field gel electrophoresis XbaI profiles, 12 different multilocus sequence types (STs), and 18 different pathogenicity array types. The relatedness of strains based on the pathogenicity gene repertoire (102 markers tested) was in good agreement with grouping by MLST. S. enterica serovar 4,[5],12:b:− is distributed across multiple unrelated eBurst groups and consequently is highly polyphyletic. Two sequence types (ST88 and ST127) were linked to S. enterica serovar Paratyphi B (d-tartrate positive), two single-locus variants of ST1583 were linked to S. enterica serovar Abony, and one sequence type (ST1484) was associated with S. enterica serovar Mygdal, a recently defined, new serovar. From the characterization of clinical isolates and those of nonhuman origin, it can be concluded that the potential sources of sporadic human infections with S. enterica serovar 4,[5],12:b:− most likely are mushrooms, shellfish/fish, and poultry. PMID:23793625

  9. Identification of Distinct Bacillus thuringiensis 4A4 Nematicidal Factors Using the Model Nematodes Pristionchus pacificus and Caenorhabditis elegans

    Science.gov (United States)

    Iatsenko, Igor; Nikolov, Angel; Sommer, Ralf J.

    2014-01-01

    Bacillus thuringiensis has been extensively used for the biological control of insect pests. Nematicidal B. thuringiensis strains have also been identified; however, virulence factors of such strains are poorly investigated. Here, we describe virulence factors of the nematicidal B. thuringiensis 4A4 strain, using the model nematodes Pristionchus pacificus and Caenorhabditis elegans. We show that B. thuringiensis 4A4 kills both nematodes via intestinal damage. Whole genome sequencing of B. thuringiensis 4A4 identified Cry21Ha, Cry1Ba, Vip1/Vip2 and β-exotoxin as potential nematicidal factors. Only Cry21Ha showed toxicity to C. elegans, while neither Cry nor Vip toxins were active against P. pacificus, when expressed in E. coli. Purified crystals also failed to intoxicate P. pacificus, while autoclaved spore-crystal mixture of B. thuringiensis 4A4 retained toxicity, suggesting that primary β-exotoxin is responsible for P. pacificus killing. In support of this, we found that a β-exotoxin-deficient variant of B. thuringiensis 4A4, generated by plasmid curing lost virulence to the nematodes. Thus, using two model nematodes we revealed virulence factors of the nematicidal strain B. thuringiensis 4A4 and showed the multifactorial nature of its virulence. PMID:25025708

  10. 40 CFR 174.504 - Bacillus thuringiensis Cry1F protein in cotton; 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 thuringiensis Cry1F protein... PLANT-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.504 Bacillus thuringiensis Cry1F protein in cotton; exemption from the requirement of a tolerance. Residues of Bacillus...

  11. A novel Bacillus thuringiensis strain LLB6, isolated from bryophytes, and its new cry2Ac-type gene.

    Science.gov (United States)

    Zhang, L L; Lin, J; Luo, L; Guan, C Y; Zhang, Q L; Guan, Y; Zhang, Y; Ji, J T; Huang, Z P; Guan, X

    2007-03-01

    To isolate and characterize the novel Bacillus thuringiensis strains from bryophytes collected from Wuyi Mountain, Fujian Province of China, and identify new B. thuringiensis strains and toxins active against mosquitoes. Twelve novel B. thuringiensis strains were isolated from 76 bryophyte samples. According to the results of this preliminary screening, LLB6 was the most toxic to Aedes albopictus. Then phase-contrast as well as scanning electron microscopy, bioassays, cloning, sequencing and expression were performed to characterize the novel isolate LLB6 and its new gene cry2Ac5. Bacillus thuringiensis occurred naturally on bryophytes. LLB6 isolated from Physcomitrium japonicum was toxic to A. albopictus. A new cry2Ac5 gene of LLB6 was detected, cloned and expressed successfully. Bioassays on A. albopictus showed that the expressed Cry2Ac5 was also toxic to the third instar larvae. This is the first report of B. thuringiensis strains isolated from bryophytes. It represents a specific source of new B. thuringiensis strains and is of great importance for the knowledge of the ecology of B. thuringiensis. Novel LLB6 harboring the new gene cry2Ac5 and its expressed Cry2Ac5 protein revealed activity against A. albopictus and became a new member of B. thuringiensis toxins.

  12. ORF Sequence: NC_005957 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available s thuringiensis serovar konkukian str. 97-27] MVKVVEGNGGKSKIKSPLNSNFKILSDLVGPTFPPVPTGMTGITGSTGATGETGATGPTGATGETGSTGNTGATGATGP...TGSTGVTGSTGATGSTGPTGNTGAMGNTGPTGETGVTGSTGPTGSTGATGNTGVTGSTGPTGETGATGPTGSTGAIGNTGATGETGSTGNTGPTGATGATGSTGP...TGSTGVTGNTGATGSTGATGNTGPTGSTGVTGNTGATGAIGPTGSTGPTGETGVTGSTGPTGNTGVTGNTGP...IGETGVTGSTGATGNTGATGSTGPTGETGVTGSTGPTGSTGATGNTGATGETGATGSTGVTGSTGATGSTGATGNTGATGETGPTGNTGVTGSTGPTGETGVTGSTGPTGNTGVTGSTGP...TGNTGVTGSTGPTGETGVTGSTGPTGNTGVTGSTGPTGETGVTGSTGPTGNTGATGNTGPTGETGVTGSTGPTGSTGVTGNTGTTGSTGNTGPTGATGSTGP

  13. New Bacillus thuringiensis toxin combinations for biological control of lepidopteran larvae.

    Science.gov (United States)

    Elleuch, Jihen; Zghal, Raida Zribi; Jemaà, Mohamed; Azzouz, Hichem; Tounsi, Slim; Jaoua, Samir

    2014-04-01

    Cyt1Aa from Bacillus thuringiensis israelensis is known by its synergistical activity with B. thuringiensis and Bacillus sphaericus toxins. It is able to improve dipteran specific toxins activity and can prevent or overcome larval resistance to those proteins. The objective of the current study was to investigate the possible improvement of larvicidal activity of B. thuringiensis kurstaki expressing heterogeneous proteins Cyt1A and P20. cyt1A98 and p20 genes encoding the cytolytic protein (Cyt1A98) and the accessory protein (P20), respectively, were introduced individually and in combination into B. thuringiensis kurstaki strain BNS3. Immunoblot analysis evidenced the expression of these genes in the recombinant strains and hinted that P20 acts as molecular chaperone protecting Cyt1A98 from proteolytic attack in BNS3. The toxicities of recombinant strains were studied and revealed that BNS3pHTp20 exhibited higher activity than that of the negative control (BNS3pHTBlue) toward Ephestia kuehniella, but not toward Spodoptera littoralis. When expressed in combination with P20, Cyt1A98 enhanced BNS3 activity against E. kuehniella and S. littoralis. Thus, Cyt1Aa protein could enhance lepidopteran Cry insecticidal activity and would prevent larval resistance to the most commercialized B. thuringiensis kurstaki toxins. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Genomic and transcriptomic insights into the efficient entomopathogenicity of Bacillus thuringiensis.

    Science.gov (United States)

    Zhu, Lei; Peng, Donghai; Wang, Yueying; Ye, Weixing; Zheng, Jinshui; Zhao, Changming; Han, Dongmei; Geng, Ce; Ruan, Lifang; He, Jin; Yu, Ziniu; Sun, Ming

    2015-09-28

    Bacillus thuringiensis has been globally used as a microbial pesticide for over 70 years. However, information regarding its various adaptions and virulence factors and their roles in the entomopathogenic process remains limited. In this work, we present the complete genomes of two industrially patented Bacillus thuringiensis strains (HD-1 and YBT-1520). A comparative genomic analysis showed a larger and more complicated genome constitution that included novel insecticidal toxicity-related genes (ITRGs). All of the putative ITRGs were summarized according to the steps of infection. A comparative genomic analysis showed that highly toxic strains contained significantly more ITRGs, thereby providing additional strategies for infection, immune evasion, and cadaver utilization. Furthermore, a comparative transcriptomic analysis suggested that a high expression of these ITRGs was a key factor in efficient entomopathogenicity. We identified an active extra urease synthesis system in the highly toxic strains that may aid B. thuringiensis survival in insects (similar to previous results with well-known pathogens). Taken together, these results explain the efficient entomopathogenicity of B. thuringiensis. It provides novel insights into the strategies used by B. thuringiensis to resist and overcome host immune defenses and helps identify novel toxicity factors.

  15. Complete genome sequence and bioinformatics analyses of Bacillus thuringiensis strain BM-BT15426.

    Science.gov (United States)

    Liu, Junyan; Li, Lin; Peters, Brian M; Li, Bing; Chen, Dingqiang; Xu, Zhenbo; Shirtliff, Mark E

    2017-07-01

    This study aimed to investigate the genetic characteristics of Bacillus thuringiensis strain BM-BT15426. B. thuringiensis strain was identified by sequencing the PCR product (amplifying 16S rRNA gene) using ABI Prism 377 DNA Sequencer. The genome was sequenced using PacBio RS II sequencers and assembled de novo using HGAP. Also, further genome annotation was performed. The genome of B. thuringiensis strain BM-BT15426 has a length of 5,246,329 bp and contains 5409 predicted genes with an average G + C content of 35.40%. Three genes were involved in the "Infectious diseases: Amoebiasis" pathway. A total of 21 virulence factors and 9 antibiotic resistant genes were identified. The major pathogenic factors of B. thuringiensis strain BM-BT15426 were identified through complete genome sequencing and bioinformatics analyses which contributes to further study on pathogenic mechanism and phenotype of B. thuringiensis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Chitinase production by Bacillus thuringiensis and Bacillus licheniformis: their potential in antifungal biocontrol.

    Science.gov (United States)

    Gomaa, Eman Zakaria

    2012-02-01

    Thirty bacterial strains were isolated from the rhizosphere of plants collected from Egypt and screened for production of chitinase enzymes. Bacillus thuringiensis NM101-19 and Bacillus licheniformis NM120-17 had the highest chitinolytic activities amongst those investigated. The production of chitinase by B. thuringiensis and B. licheniformis was optimized using colloidal chitin medium amended with 1.5% colloidal chitin, with casein as a nitrogen source, at 30°C after five days of incubation. An enhancement of chitinase production by the two species was observed by addition of sugar substances and dried fungal mats to the colloidal chitin media. The optimal conditions for chitinase activity by B. thuringiensis and B. licheniformis were at 40°C, pH 7.0 and pH 8.0, respectively. Na(+), Mg(2+), Cu(2+), and Ca(2+) caused enhancement of enzyme activities whereas they were markedly inhibited by Zn(2+), Hg(2+), and Ag(+). In vitro, B. thuringiensis and B. licheniformis chitinases had potential for cell wall lysis of many phytopathogenic fungi tested. The addition of B. thuringiensis chitinase was more effective than that of B. licheniformis in increasing the germination of soybean seeds infected with various phytopathogenic fungi.

  17. Pathogenomic sequence analysis of Bacillus cereus and Bacillus thuringiensis isolates closely related to Bacillus anthracis.

    Science.gov (United States)

    Han, Cliff S; Xie, Gary; Challacombe, Jean F; Altherr, Michael R; Bhotika, Smriti S; Brown, Nancy; Bruce, David; Campbell, Connie S; Campbell, Mary L; Chen, Jin; Chertkov, Olga; Cleland, Cathy; Dimitrijevic, Mira; Doggett, Norman A; Fawcett, John J; Glavina, Tijana; Goodwin, Lynne A; Green, Lance D; 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 Philip; Richardson, Paul; Robinson, Donna L; Rubin, Eddy; Saunders, Elizabeth; Tapia, Roxanne; Tesmer, Judith G; Thayer, Nina; Thompson, Linda S; Tice, Hope; Ticknor, Lawrence O; Wills, Patti L; Brettin, Thomas S; Gilna, Paul

    2006-05-01

    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 serotype H34, isolated from a necrotic human wound, and B. cereus E33L, which was isolated from a swab of a zebra carcass in Namibia. These two strains, when analyzed by amplified fragment length polymorphism within a collection of over 300 of B. cereus, B. thuringiensis, and B. anthracis isolates, appear closely related to B. anthracis. The B. cereus E33L isolate appears to be the nearest relative to B. anthracis identified thus far. Whole-genome sequencing of B. thuringiensis 97-27and B. cereus E33L was undertaken to identify shared and unique genes among these isolates in comparison to the genomes of pathogenic strains B. anthracis Ames and B. cereus G9241 and nonpathogenic strains B. cereus ATCC 10987 and B. cereus ATCC 14579. Comparison of these genomes revealed differences in terms of virulence, metabolic competence, structural components, and regulatory mechanisms.

  18. Translocation of Bacillus thuringiensis in Phaseolus vulgaris tissues and vertical transmission in Arabidopsis thaliana.

    Science.gov (United States)

    García-Suárez, R; Verduzco-Rosas, L A; Del Rincón-Castro, M C; Délano-Frier, J P; Ibarra, J E

    2017-04-01

    To demonstrate the ability of Bacillus thuringiensis to penetrate as spore-crystal complex to the internal tissues of bean plants, and keep its insecticidal activity. To test the vertical transmission of the spore-crystal complex in Arabidopsis thaliana. The experimental strain was transformed with the pMUTIN-gfp plasmid which labelled the spores of B. thuringiensis HD-73 with the GFP protein. Once the rhizosphere of the bean plants was inoculated with the labelled strain, the bacterium was recovered from leaves, stems, and petioles. Furthermore, toxicity of treated plants was significantly higher than control plants when bio-assayed on cabbage looper larvae. The labelled strain was recovered from the dead insects. When the rhizosphere of A. thaliana plants was inoculated with the labelled strain, mature seeds from these plants were surface-sterilized and grown under in vitro conditions. The labelled strain was recovered from the seedlings. We showed that B. thuringiensis subsp. kurstaki (HD-73) in the rhizosphere can translocate to upper tissues of bean plants, and keep its insecticidal activity. Transmission of the labelled B. thuringiensis strain passed to the next generation of A. thaliana. The role of B. thuringiensis as a potential facultative endophyte bacterium and the possible biotechnological repercussions are discussed. © 2017 The Society for Applied Microbiology.

  19. Screening of Bacillus thuringiensis strains effective against mosquitoes Prospecção de estirpes de Bacillus thuringiensis efetivas contra mosquitos

    Directory of Open Access Journals (Sweden)

    Rose Gomes Monnerat

    2005-02-01

    Full Text Available The objective of this work was to evaluate 210 Bacillus thuringiensis strains against Aedes aegypti and Culex quinquefasciatus larvae to select the most effective. These strains were isolated from different regions of Brazil and are stored in a Bacillus spp. collection at Embrapa Recursos Genéticos e Biotecnologia, Brasília, Brazil. The selected strains were characterized by morphological (microscopy, biochemical (SDS-PAGE 10% and molecular (PCR methods. Six B. thuringiensis strains were identified as mosquito-toxic after the selective bioassays. None of the strains produced the expected PCR products for detection of cry4, cry11 and cyt1A genes. These results indicate that the activity of mosquitocidal Brazilian strains are not related with Cry4, Cry11 or Cyt proteins, so they could be used as an alternative bioinsecticide against mosquitoes.Neste trabalho foram realizados testes de patogenicidade com 210 estirpes de Bacillus thuringiensis contra larvas de Aedes aegypti e Culex quinquefasciatus, a fim de se determinar as mais eficazes. Estas estirpes foram isoladas de diversas regiões do Brasil e estão armazenadas na coleção de Bacillus spp. da Embrapa Recursos Genéticos e Biotecnologia. As estirpes selecionadas foram caracterizadas por métodos morfológicos (microscopia, bioquímicos (SDS-PAGE 10% e moleculares (Reação em Cadeia da Polimerase. Foram selecionadas seis estirpes entomopatogênicas de Bacillus thuringiensis. Nenhuma das estirpes de Bacillus thuringiensis apresentou produtos de PCR esperados para a detecção dos genes cry4, cry11 e cyt1A. A patogenicidade das estirpes não está associada à presença das toxinas Cry4, Cry11 ou Cyt, assim, essas estirpes poderão ser utilizadas para a formatação de um bioinseticida alternativo contra mosquitos.

  20. Circulating serovars of Leptospira in cart horses of central and southern Ethiopia and associated risk factors.

    Science.gov (United States)

    Tsegay, K; Potts, A D; Aklilu, N; Lötter, C; Gummow, B

    2016-03-01

    Little work has been done on diseases of horses in Ethiopia or tropical regions of the world. Yet, Ethiopia has the largest horse population in Africa and their horses play a pivotal role in their economy as traction animals. A serological and questionnaire survey was therefore conducted to determine the circulating serovars of Leptospira and their association with potential risk factors in the cart horse population of Central and Southern Ethiopia. A total of 184 out of 418 cart horses from 13 districts had antibody titres of 1:100 or greater to at least one of 16 serovars of Leptospira species in Central and Southern Ethiopian horses. A significantly higher seropositivity (62.1%) was noted in horses from the highland agroecology followed by midland (44.4%) and lowland (39.8%). Serovar Bratislava (34.5%) was the predominant serovar followed by serovars Djasiman (9.8%), Topaz (5.98%) and Pomona (5.3%). Age and location proved to be associated with seropositive horses with older horses being more commonly affected and the districts of Ziway (Batu) (Apparent Prevalence (AP)=65.5%), Shashemene (AP=48.3%) and Sebeta (AP=41.4%) having the highest prevalence. Multivariable logistic regression found risk factors significantly associated with Leptospira seropositive horses were drinking river water (OR=2.8) and horses 7-12 years old (OR=5) and risk factors specifically associated with serovar Bratislava seropositive horses were drinking river water (OR=2.5), horses ≥13 years (OR=3.5) and the presence of dogs in adjacent neighbouring properties (OR=0.3). Dogs had a protective effect against seropositivity to serovars Bratislava and Djasiman, which may be due to their ability to control rodents. The high seroprevalence confirm that leptospirosis is endemic among horses of Central and Southern Ethiopia. The predominance of serovar Bratislava supports the idea that serovar Bratislava may be adapted to and maintained by the horse population of Central and Southern Ethiopia

  1. Effect of inherited sterility and bacillus thuringiensis on mortality and reproduction of phthorimaea opercullela zeller (lepidoptera: gelechidae)

    International Nuclear Information System (INIS)

    Makee, H.; Tlas, M. D.; Amer, S.; Abdulla, J.

    2008-01-01

    The effect of a commercial formulation of Bacillus thuringiensis (Dipel 2X) upon F 1 progeny of irradiated and unirradiated phthorimaea operculella male parents was investigated. F 1 progeny of irradiated parents was more susceptible to B. thuringiensis than that of unirradiated parents. A combination of irradiation and B. thuringiensis led to higher mortality in F 1 progeny of P. operculella. The LC 50 was 0.406 g/100ml for F 1 progeny of unirradiated parents, but 0.199 g/100ml for those of irradiated parents. There was a great reduction in the pupal weight, fecundity and egg hatchability of F 1 progeny of irradiated patents compared to those unirradiated parents. Such reduction was increased by applying higher concentration of B. thuringiensis. A combination between inherited sterility technique and B. thuringiensis application could give a good controlling result against P. operculella. (author)

  2. Detection of Salmonella enterica Serovar Typhimurium from Avians Using Multiplex-PCR

    Directory of Open Access Journals (Sweden)

    Alireza Talebi

    2011-09-01

    Full Text Available Abstract Salmonella enterica serovar Typhimurium and S.enterica serovar Enteritidis are the most frequently isolated serovars from food-borne diseases throughout the world. According to their antigenic profiles, salmonella shows different disease syndromes and host specificities. It is necessary and important to discriminate salmonella serovars from each other in order to ensure that each pathogen and its epidemiology are correctly recognized. Many PCR-based methods have been developed to identify salmonella serovars. The objective of present study was to identify S. Typhimurium in avians from different regions including: North, Northwest and capital city (Tehran of Iran. Also in this research, the quality of CHROMagar™ Salmonella medium (CAS medium in veterinary medicine was evaluated. The results of present study showed that out of 1870 intestine samples, fifty two S. Typhimurium including broiler (n=13, layer (n=12, duck (n=5, goose (n=5, sparrow (n=8, canary (n=3, pigeon (n=5 and African grey parrot (n=1 were identified using serotyping as well as multiplex-PCR. In conclusion, important measures must be taken on prevention and propagation of S. Typhimurium among avians. CHROMagar™ Salmonella medium has high levels of sensitivity and specificity and reduced the time to final identification of salmonella spp. in comparison with biochemical tests.

  3. Genome-wide methylation patterns in Salmonella enterica Subsp. enterica Serovars.

    Directory of Open Access Journals (Sweden)

    Cary Pirone-Davies

    Full Text Available The methylation of DNA bases plays an important role in numerous biological processes including development, gene expression, and DNA replication. Salmonella is an important foodborne pathogen, and methylation in Salmonella is implicated in virulence. Using single molecule real-time (SMRT DNA-sequencing, we sequenced and assembled the complete genomes of eleven Salmonella enterica isolates from nine different serovars, and analysed the whole-genome methylation patterns of each genome. We describe 16 distinct N6-methyladenine (m6A methylated motifs, one N4-methylcytosine (m4C motif, and one combined m6A-m4C motif. Eight of these motifs are novel, i.e., they have not been previously described. We also identified the methyltransferases (MTases associated with 13 of the motifs. Some motifs are conserved across all Salmonella serovars tested, while others were found only in a subset of serovars. Eight of the nine serovars contained a unique methylated motif that was not found in any other serovar (most of these motifs were part of Type I restriction modification systems, indicating the high diversity of methylation patterns present in Salmonella.

  4. Isolation and Characterization of Salmonella Enterica Serovar Typhimurium Circulating Among Healthy Chickens of Bangladesh

    Directory of Open Access Journals (Sweden)

    Md. Shafiullah Parvej

    2016-07-01

    Full Text Available Salmonella is considered as a global problem ranking first among food borne diseases. All motile Salmonella of poultry origin are zoonotic and readily transmit to human via meat and eggs but reports on non - typhoidal Salmonella serovars circulating in layer chickens is very limited in South-East Asian countries including Bangladesh. Salmonella serovars isolated from apparently healthy chickens were characterized in the present study. Of 170 samples (cloacal swab 150 and feed 20 collected from commercial layer farms, motile Salmonella was isolated 4% (6/150 and 50% (10/20 respectively by cultural, biochemical, motility test and by detection of hisJ gene. About 5% (8/170 samples possessed serovar-specific gene fimA, suggesting that isolates were Salmonella enterica serovar Typhimurium. Antimicrobial susceptibility testing demonstrated that the isolated serovars were multidrug resistant. Therefore apparently healthy layer chickens harbour and transmit S. Typhimurium to the environment, although little is alarming since it has zoonotic significance and the isolates were resistant to commonly used first line of antibiotic in Salmonella infection.

  5. Salmonella serovars along two beef chains in Ethiopia.

    Science.gov (United States)

    Hiko, Adem; Irsigler, Herlinde; Ameni, Gobena; Zessin, Karl-Hans; Fries, Reinhard

    2016-11-24

    Salmonella has been reported from foods and the food production environment, with outbreaks occurring in the human population worldwide. A survey on Salmonella in two beef production lines (a beef abattoir line and a processing line) in Addis Ababa, Ethiopia was conducted, with a total of 668 various samples randomly collected from animal-related materials, the environment, and a beef product (mortadella). Overall, a 12.9% prevalence (26.3% from the abattoir line, 5.3% from the processing plant line) was observed. The prevalence in the abattoir line environment (36.6%) was higher than that in animal-related samples (14.7%); the reverse was true for the processing plant line. Out of 86 isolates, 10 serovars were identified, and 8 remained unidentified. The predominant serotypes were S. Saintpaul (32.5%), S. Muenchen (19.8%), and S. Larochelle (12.8%). S. Kastrup and S. London were isolated for the first time in Ethiopia. Data indicate open ports of entry for Salmonella, with possible transfer along the line. Further investigations from farm to fork are recommended in order to identify these positions of entry.

  6. Prevalence, serovars and antimicrobial susceptibility of Salmonella spp. from wild and domestic green iguanas (Iguana iguana) in Grenada, West Indies.

    Science.gov (United States)

    Sylvester, W R B; Amadi, V; Pinckney, R; Macpherson, C N L; McKibben, J S; Bruhl-Day, R; Johnson, R; Hariharan, H

    2014-09-01

    Cloacal swabs from 62 green iguanas (Iguana iguana), including 47 wild and 15 domestic ones from five parishes of Grenada, were sampled during a 4-month period of January to April 2013 and examined by enrichment and selective culture for the presence of Salmonella spp. Fifty-five per cent of the animals were positive, and eight serovars of Salmonella were isolated. The most common serovar was Rubislaw (58.8%), a serovar found recently in many cane toads in Grenada, followed by Oranienburg (14.7%), a serovar that has been causing serious human disease outbreaks in Japan. Serovar IV:48:g,z51 :- (formerly, S. Marina) highly invasive and known for serious infections in children in the United States, constituted 11.8% of the isolates, all of them being from domestic green iguanas. Salmonella Newport, a serovar recently found in a blue land crab in Grenada, comprised 11.8% of the isolates from the green iguanas. The remaining four less frequent serovars included S. Javiana and S. Glostrup. Antimicrobial susceptibility tests conducted by a disc diffusion method against amoxicillin-clavulanic acid, ampicillin, cefotaxime, ceftazidime, ciprofloxacin, enrofloxacin, gentamicin, nalidixic acid, streptomycin, tetracycline and trimethoprim-sulfamethoxazole showed that drug resistance is minimal, with intermediate susceptibility, mainly to streptomycin, tetracycline and cefotaxime. This is the first report of isolation and antimicrobial susceptibilities of various Salmonella serovars from wild and domestic green iguanas in Grenada, West Indies. © 2013 Blackwell Verlag GmbH.

  7. Buenos Aires, a new Leptospira serovar of serogroup Djasiman, isolated from an aborted dog fetus in Argentina

    NARCIS (Netherlands)

    Rossetti, Carlos A.; Liem, Marije; Samartino, Luis E.; Hartskeerl, Rudy A.

    2005-01-01

    This study describes the isolation of a new leptospiral serovar from the Djasiman group from an Argentinean aborted fetus of a dog. The strain was isolated from a culture of mixed liver and kidney tissue from one aborted dog fetus. Bitch's serum showed a titre of 1:800 against the new serovar and

  8. Development of Real Time PCR Using Novel Genomic Target for Detection of Multiple Salmonella Serovars from Milk and Chickens

    Science.gov (United States)

    Background: A highly sensitive and specific novel genomic and plasmid target-based PCR platform was developed to detect multiple Salmonella serovars (S. Heidelberg, S. Dublin, S. Hadar, S. Kentucky and S. Enteritidis). Through extensive genome mining of protein databases of these serovars and compar...

  9. Application of molecular methods for identification of strains classified as Salmonella enterica serovar 6, 7/-/- by conventional serotyping

    DEFF Research Database (Denmark)

    Chadfield, M. S.; Christensen, J. P.; Madsen, Mogens

    2002-01-01

    An increased prevalence of Salmonella enterica serovar Tennessee (6, 7: z(29):-) was observed in broiler flocks in Denmark in 1994 and a parallel increase in the prevalence of Salmonella enterica serovar 6, 7:-:- was demonstrated, albeit at a lower level. Plasmid profiling and ribotyping revealed...

  10. A Leptospira borgpetersenii Serovar Hardjo vaccine induces a Th1 response, activates NK cells, and reduces renal colonization

    Science.gov (United States)

    Chronic infection of cattle with Leptospira borgpetersenii serovar Hardjo reduces animal production through reproductive failure and presents a persistent health threat to workers in the animal industry. Cattle are maintenance hosts for serovar Hardjo and development of a protective vaccine has bee...

  11. Differentiation between Bacillus thuringiensis strains by gyrB PCR-Sau3AI fingerprinting.

    Science.gov (United States)

    Awad, Mireille Kallassy; Saadaoui, Imène; Rouis, Souad; Tounsi, Slim; Jaoua, Samir

    2007-02-01

    gyrB DNA fragments of seven Bacillus thuringiensis local collection family representatives were amplified by PCR and sequenced. Several differences in their corresponding sequences were evidenced. Both in silico and in vitro restriction maps of gyrB sequences and fragments respectively confirmed that EcoRI and Sau3AI could be used to differentiate between B. thuringiensis strains. However, the phylogeny analysis showed that only the gyrB PCR-Sau3AI allows a strains classification that correlates very well with that obtained on the basis of the sequences analysis. Thus, these finds show that gyrB PCR- Sau3AI digestion could be considered as an efficient, rapid, and easy method to make a distinction, not only between strains belonging to the Bacillus cereus group, but also between those belonging to B. thuringiensis.

  12. Heat tolerance of Salmonella enterica serovars Agona, Enteritidis, and Typhimurium in peanut butter.

    Science.gov (United States)

    Shachar, Dina; Yaron, Sima

    2006-11-01

    Recent large foodborne outbreaks caused by Salmonella enterica serovars have been associated with consumption of foods with high fat content and reduced water activity, even though their ingredients usually undergo pasteurization. The present study was focused on the heat tolerance of Salmonella enterica serovars Agona, Enteritidis, and Typhimurium in peanut butter. The Salmonella serovars in the peanut butter were resistant to heat, and even at a temperature as high as 90 degrees C only 3.2-log reduction in CFU was observed. The obtained thermal inactivation curves were upwardly concave, indicating rapid death at the beginning (10 min) followed by lower death rates and an asymptotic tail. The curves fitted the nonlinear Weibull model with beta parameters pasteurization process cannot be improved significantly by longer treatment or higher temperatures.

  13. Bacillus thuringiensis: fermentation process and risk assessment: a short review

    Directory of Open Access Journals (Sweden)

    Deise M. F Capalbo

    1995-02-01

    Full Text Available Several factors make the local production of Bacillus thuringiensis (Bt highly appropriate for pest control in developing nations. Bt can be cheaply produced on a wide variety of low cost, organic substrates. Local production results in considerable savings in hard currency which otherwise would be spent on importation of chemical and biological insecticides. The use of Bt in Brazil has been limited in comparison with chemical insecticides. Although Bt is imported, some Brazilian researchers have been working on its development and production. Fermentation processes (submerged and semi-solid were applied, using by-products from agro-industries. As the semi-solid fermentation process demonstrated to be interesting for Bt endotoxins production, it could be adopted for small scale local production. Although promising results had been achieved, national products have not been registered due to the absence of a specific legislation for biological products. Effective actions are being developed in order to solve this gap. Regardless of the biocontrol agents being considered atoxic and harmless to the environment, information related to direct and indirect effects of microbials are still insufficient in many cases. The risk analysis of the use of microbial control agents is of upmost importance nowadays, and is also discussed.

  14. Bacillus thuringiensis Toxins: An Overview of Their Biocidal Activity

    Science.gov (United States)

    Palma, Leopoldo; Muñoz, Delia; Berry, Colin; Murillo, Jesús; Caballero, Primitivo

    2014-01-01

    Bacillus thuringiensis (Bt) is a Gram positive, spore-forming bacterium that synthesizes parasporal crystalline inclusions containing Cry and Cyt proteins, some of which are toxic against a wide range of insect orders, nematodes and human-cancer cells. These toxins have been successfully used as bioinsecticides against caterpillars, beetles, and flies, including mosquitoes and blackflies. Bt also synthesizes insecticidal proteins during the vegetative growth phase, which are subsequently secreted into the growth medium. These proteins are commonly known as vegetative insecticidal proteins (Vips) and hold insecticidal activity against lepidopteran, coleopteran and some homopteran pests. A less well characterized secretory protein with no amino acid similarity to Vip proteins has shown insecticidal activity against coleopteran pests and is termed Sip (secreted insecticidal protein). Bin-like and ETX_MTX2-family proteins (Pfam PF03318), which share amino acid similarities with mosquitocidal binary (Bin) and Mtx2 toxins, respectively, from Lysinibacillus sphaericus, are also produced by some Bt strains. In addition, vast numbers of Bt isolates naturally present in the soil and the phylloplane also synthesize crystal proteins whose biological activity is still unknown. In this review, we provide an updated overview of the known active Bt toxins to date and discuss their activities. PMID:25514092

  15. Adhesion of Spores of Bacillus thuringiensis on a Planar Surface

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Eunhyea [Georgia Institute of Technology; Kweon, Hyojin [Georgia Institute of Technology; Yiacoumi, Sotira [Georgia Institute of Technology; Lee, Ida [University of Tennessee, Knoxville (UTK); Joy, David Charles [ORNL; Palumbo, Anthony Vito [ORNL; Tsouris, Costas [ORNL

    2010-01-01

    Adhesion of spores of Bacillus thuringiensis (Bt) and spherical silica particles on surfaces was experimentally and theoretically investigated in this study. Topography analysis via atomic force microscopy (AFM) and electron microscopy indicates that Bt spores are rod shaped, {approx}1.3 {mu}m in length and {approx}0.8 {mu}m in diameter. The adhesion force of Bt spores and silica particles on gold-coated glass was measured at various relative humidity (RH) levels by AFM. It was expected that the adhesion force would vary with RH because the individual force components contributing to the adhesion force depend on RH. The adhesion force between a particle and a planar surface in atmospheric environments was modeled as the contribution of three major force components: capillary, van der Waals, and electrostatic interaction forces. Adhesion force measurements for Bt spore (silica particle) and the gold surface system were comparable with calculations. Modeling results show that there is a critical RH value, which depends on the hydrophobicity of the materials involved, below which the water meniscus does not form and the contribution of the capillary force is zero. As RH increases, the van der Waals force decreases while the capillary force increases to a maximum value.

  16. Raman spectroscopy of Bacillus thuringiensis physiology and inactivation

    Science.gov (United States)

    Morrow, J. B.; Almeida, J.; Cole, K. D.; Reipa, V.

    2012-12-01

    The ability to detect spore contamination and inactivation is relevant to developing and determining decontamination strategy success for food and water safety. This study was conducted to develop a systematic comparison of nondestructive vibrational spectroscopy techniques (Surface-Enhanced Raman Spectroscopy, SERS, and normal Raman) to determine indicators of Bacillus thuringiensis physiology (spore, vegetative, outgrown, germinated and inactivated spore forms). SERS was found to provide better resolution of commonly utilized signatures of spore physiology (dipicolinic acid at 1006 cm-1 and 1387 cm-1) compared to normal Raman and native fluorescence indigenous to vegetative and outgrown cell samples was quenched in SERS experiment. New features including carotenoid pigments (Raman features at 1142 cm-1, 1512 cm-1) were identified for spore cell forms. Pronounced changes in the low frequency region (300 cm-1 to 500 cm-1) in spore spectra occurred upon germination and inactivation (with both free chlorine and by autoclaving) which is relevant to guiding decontamination and detection strategies using Raman techniques.

  17. Bacillus thuringiensis Toxins: An Overview of Their Biocidal Activity

    Directory of Open Access Journals (Sweden)

    Leopoldo Palma

    2014-12-01

    Full Text Available Bacillus thuringiensis (Bt is a Gram positive, spore-forming bacterium that synthesizes parasporal crystalline inclusions containing Cry and Cyt proteins, some of which are toxic against a wide range of insect orders, nematodes and human-cancer cells. These toxins have been successfully used as bioinsecticides against caterpillars, beetles, and flies, including mosquitoes and blackflies. Bt also synthesizes insecticidal proteins during the vegetative growth phase, which are subsequently secreted into the growth medium. These proteins are commonly known as vegetative insecticidal proteins (Vips and hold insecticidal activity against lepidopteran, coleopteran and some homopteran pests. A less well characterized secretory protein with no amino acid similarity to Vip proteins has shown insecticidal activity against coleopteran pests and is termed Sip (secreted insecticidal protein. Bin-like and ETX_MTX2-family proteins (Pfam PF03318, which share amino acid similarities with mosquitocidal binary (Bin and Mtx2 toxins, respectively, from Lysinibacillus sphaericus, are also produced by some Bt strains. In addition, vast numbers of Bt isolates naturally present in the soil and the phylloplane also synthesize crystal proteins whose biological activity is still unknown. In this review, we provide an updated overview of the known active Bt toxins to date and discuss their activities.

  18. Biopesticide production from Bacillus thuringiensis: an environmentally friendly alternative.

    Science.gov (United States)

    Rosas-García, Ninfa M

    2009-01-01

    Since its discovery as a microbial insecticide, Bacillus thuringiensis has been widely used to control insect pests important in agriculture, forestry, and medicine. The wide variety of formulations based on spore-crystal complexes intended for ingestion by target insects, are the result of many years of research. The development of a great variety of matrices for support of the spore-crystal complex enables many improvements, such as an increase in toxic activity, higher palatability to insects, or longer shelf lives. These matrices use many chemical, vegetable or animal compounds to foster contact between crystals and insect midguts, without harming humans or the environment. Biotechnology companies are tasked with the production of these kinds of bioinsecticides. These companies must not only provide formulations tailored to specific crops and the insect pests, but they must also search for and produce bioinsecticides based on new strains of high potency, whether wild or genetically improved. It is expected that new products will appear on the market soon, providing an increased activity spectrum and applicability to many other pest-impacted crops. These products may help develop a more organic agriculture. This review article discusses recent patents related to bioinsecticides.

  19. Prevalence of Salmonella spp., and serovars isolated from captive exotic reptiles in New Zealand.

    Science.gov (United States)

    Kikillus, K H; Gartrell, B D; Motion, E

    2011-07-01

    To investigate the prevalence of Salmonella spp. in captive exotic reptile species in New Zealand, and identify the serovars isolated from this population. Cloacal swabs were obtained from 378 captive exotic reptiles, representing 24 species, residing in 25 collections throughout New Zealand between 2008 and 2009. Samples were cultured for Salmonella spp., and suspected colonies were serotyped by the Institute of Environmental Science and Research (ESR). Forty-three of the 378 (11.4%) reptiles sampled tested positive for Salmonella spp., with 95% CI for the estimated true prevalence being 12-25% in exotic reptiles in this study population. Lizards tested positive for Salmonella spp. more often than chelonians. Agamid lizards tested positive more often than any other family group, with 95% CI for the estimated true prevalence being 56-100%.. Six Salmonella serovars from subspecies I and two from subspecies II were isolated. The serovar most commonly isolated was S. Onderstepoort (30.2%), followed by S. Thompson (20.9%), S. Potsdam (14%), S. Wangata (14%), S. Infantis (11.6%) and S. Eastbourne (2.3%). All of the subspecies I serovars have been previously reported in both reptiles and humans in New Zealand, and include serovars previously associated with disease in humans. This study showed that Salmonella spp. were commonly carried by exotic reptiles in the study population in New Zealand. Several serovars of Salmonella spp. with known pathogenicity to humans were isolated, including S. Infantis, which is one of the most common serovars isolated from both humans and non-human sources in New Zealand. The limitations of this study included the bias engendered by the need for voluntary involvement in the study, and the non-random sampling design. Based on the serovars identified in this and previous studies, it is recommended native and exotic reptiles be segregated within collections, especially when native reptiles may be used for biodiversity restoration

  20. Variable carbon catabolism among Salmonella enterica serovar Typhi isolates.

    Directory of Open Access Journals (Sweden)

    Lay Ching Chai

    Full Text Available BACKGROUND: Salmonella enterica serovar Typhi (S. Typhi is strictly a human intracellular pathogen. It causes acute systemic (typhoid fever and chronic infections that result in long-term asymptomatic human carriage. S. Typhi displays diverse disease manifestations in human infection and exhibits high clonality. The principal factors underlying the unique lifestyle of S. Typhi in its human host during acute and chronic infections remain largely unknown and are therefore the main objective of this study. METHODOLOGY/PRINCIPAL FINDINGS: To obtain insight into the intracellular lifestyle of S. Typhi, a high-throughput phenotypic microarray was employed to characterise the catabolic capacity of 190 carbon sources in S. Typhi strains. The success of this study lies in the carefully selected library of S. Typhi strains, including strains from two geographically distinct areas of typhoid endemicity, an asymptomatic human carrier, clinical stools and blood samples and sewage-contaminated rivers. An extremely low carbon catabolic capacity (27% of 190 carbon substrates was observed among the strains. The carbon catabolic profiles appeared to suggest that S. Typhi strains survived well on carbon subtrates that are found abundantly in the human body but not in others. The strains could not utilise plant-associated carbon substrates. In addition, α-glycerolphosphate, glycerol, L-serine, pyruvate and lactate served as better carbon sources to monosaccharides in the S. Typhi strains tested. CONCLUSION: The carbon catabolic profiles suggest that S. Typhi could survive and persist well in the nutrient depleted metabolic niches in the human host but not in the environment outside of the host. These findings serve as caveats for future studies to understand how carbon catabolism relates to the pathogenesis and transmission of this pathogen.

  1. Characterization of Salmonella enterica serovar Typhimurium and Salmonella enterica serovar 4,[5],12:i:- isolates from pigs presenting with diarrhea in Korea.

    Science.gov (United States)

    Lee, Ki-Eun; Lee, Deog-Yong; Choi, Hwan-Won; Chae, Su-Jin; Yun, Young-Sun; Lee, Ki-Chan; Cho, Yun-Sang; Yang, Dong-Kun

    2015-11-01

    Between 2011 and 2012, a total of 896 pig fecal samples were collected from nine provinces in Korea, and 50 salmonella enterica susp. enterica serovar Typhimurium (S. Typhimurium) was isolated. The characteristics of the 50 strains were analyzed, and 4 strains were identified as Salmonella enterica subsp. enterica serovar 4,[5],12:i:-. Salmonella 4,[5],12:i:- could not be distinguished from S. Typhimurium through phage typing, antimicrobial resistance testing or multiple-locus variable-number tandem repeat analysis (MLVA). However, among the four Salmonella 4,[5],12:i:- strains, one (KVCC-BA1400078) was identified as a Salmonella 4,[5],12:i:- clone isolated from humans in the United States, and another (KVCC-BA1400080) was identified as DT193, which has been primarily isolated from humans and animals in European countries. The presence of Salmonella 4,[5],12:i:- in Korea poses a significant threat of horizontal transfer between pigs and humans.

  2. Effect of Bacillus thuringiensis on microbial functional groups in sorghum rhizosphere Efeito do Bacillus thuringiensis sobre grupos funcionais de microrganismos na rizosfera de sorgo

    Directory of Open Access Journals (Sweden)

    Carlos Brasil

    2006-05-01

    Full Text Available The objective of this work was to assess the effect of two strains of Bacillus thuringiensis var. kurstaki on sorghum rhizosphere microorganisms. The strains were HD1, that produces the bioinsecticidal protein, and 407, that is a mutant non-producer. The strains do not influence microbial population, but reduce plant growth and improve mycorrhizal colonization and free living fixing N2 community.O objetivo deste trabalho foi avaliar o efeito de duas cepas de Bacillus thuringiensis var. kurstaki sobre microrganismos na rizosfera do sorgo. As cepas foram a HD1, produtora do cristal bioinseticida, e a 407, uma mutante não-produtora. As duas cepas não influenciam a comunidade microbiana, mas reduzem o crescimento da planta. A colonização micorrízica e a população de fixadores de N2 de vida livre aumentaram.

  3. Complete Genome and Methylome Sequences of Salmonella enterica subsp. enterica Serovar Panama (ATCC 7378) and Salmonella enterica subsp. enterica Serovar Sloterdijk (ATCC 15791)

    OpenAIRE

    Yao, Kuan; Muruvanda, Tim; Roberts, Richard J.; Payne, Justin; Allard, Marc W.; Hoffmann, Maria

    2016-01-01

    Salmonella enterica spp. are pathogenic bacteria commonly associated with food-borne outbreaks in human and animals. Salmonella enterica spp. are characterized into more than 2,500 different serotypes, which makes epidemiological surveillance and outbreak control more difficult. In this report, we announce the first complete genome and methylome sequences from two Salmonella type strains associated with food-borne outbreaks, Salmonella enterica subsp. enterica serovar Panama (ATCC 7378) and S...

  4. Advances in developing Bacillus thuringiensis-based insecticde formulations Avances en el desarrollo de formulaciones insecticidas a base de Bacillus thuringiensis

    OpenAIRE

    Rosas-García Ninfa María

    2008-01-01

    Developing Bacillus thuringiensis-based formulations is an old technology which has been revived during recent decades. The spore-crystal complex (being the main ingredient in these preparations) has been the main objective of this research, involving the search for new or improved strains. The type of materials used included a wide variety of completely biodegradable ingredients which could have been leaves, stems or fruit which when dried and ground could serve as feeding stimulants, as wel...

  5. Estirpes de Bacillus thuringiensis efetivas contra insetos das ordens Lepidoptera, Coleoptera e Diptera Bacillus thuringiensis strains effective against insects of Lepidoptera, Coleoptera and Diptera orders

    Directory of Open Access Journals (Sweden)

    Lílian Botelho Praça

    2004-01-01

    Full Text Available O objetivo deste trabalho foi selecionar entre 300 estirpes de Bacillus thuringiensis as efetivas simultaneamente contra larvas de Spodoptera frugiperda J.E. Smith e Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae, Anthonomus grandis Boheman (Coleoptera: Curculionidae, Aedes aegypti Linnaeus e Culex quinquefasciatus Say (Diptera: Culicidae. Foram selecionadas duas estirpes de B. thuringiensis, denominadas S234 e S997, que apresentaram atividade contra as três ordens de insetos. As estirpes foram caracterizadas por métodos morfológicos, bioquímicos e moleculares. As mesmas apresentaram duas proteínas principais de 130 e 65 kDa, produtos de reação em cadeia da polimerase de tamanho esperado para a detecção dos genes cry1Aa, cry1Ab, cry1Ac, cry1B e cry2 e cristais bipiramidais, cubóides e esféricos.The aim of this work was to select among 300 strains of Bacillus thuringiensis those which are simultaneously effective against larvae of Spodoptera frugiperda J.E. Smith and Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae, Anthonomus grandis Boheman (Coleoptera: Curculionidae, Aedes aegypti Linnaeus and Culex quinquefasciatus Say (Diptera: Culicidae. Two strains of B. thuringiensis were selected, S234 and S997, which presented activity against those three insect orders. Both strains were characterized by morphological, biochemical and molecular methods. They have presented two main proteins with 130 and 65 kDa, polimerase chain reaction products with expected sizes for detection of the genes cry1Aa, cry1Ab, cry1Ac, cry1B and cry2 and bipiramidal, cubical and spherical crystals.

  6. Porcine Response to a Multidrug-Resistant Salmonella enterica serovar I 4,[5],12:i:- Outbreak Isolate.

    Science.gov (United States)

    Shippy, Daniel C; Bearson, Bradley L; Holman, Devin B; Brunelle, Brian W; Allen, Heather K; Bearson, Shawn M D

    2018-02-07

    Salmonella enterica serovar I 4,[5],12:i:- has emerged as a common nontyphoidal Salmonella serovar to cause human foodborne illness. An interesting trait of serovar I 4,[5],12:i:- is that it only expresses the fliC gene for bacterial motility (i.e., monophasic), while most Salmonella strains alternately express two flagellin genes (fliC and fljB). The goal of this study was to characterize the porcine response following inoculation with a multidrug-resistant (MDR) serovar I 4,[5],12:i:- isolate associated with a multistate pork outbreak to determine if the increased prevalence of serovar I 4,[5],12:i:- in swine is due to enhanced pathogenicity. Pigs were inoculated and subsequently evaluated for the ability of the isolate to colonize intestinal tissues, cause clinical symptoms, induce an immune response, and alter the fecal microbiota over a 7-day period. Pigs exhibited a significant increase in rectal temperature (fever) (p isolate induced transient clinical disease in swine and perturbed the gastrointestinal microbial community. The porcine response to MDR serovar I 4,[5],12:i:- is similar to previous studies with virulent biphasic Salmonella enterica serovar Typhimurium, suggesting that the absence of fljB does not substantially alter acute colonization or pathogenesis in pigs.

  7. A method for in Vivo radiolabeling Bacillus thuringiensis native δ-endotoxin crystals

    Science.gov (United States)

    C. Noah Koller; Leah S. Bauer; Robert M. Hollingworth

    1995-01-01

    The entomocidal CryIIIA δ-endotoxin protein of Bacillus thuringiensis var. tenebrionis is distinctive in chemistry and host range. In contrast to other δ-endotoxins, the CryIIIA parasporal crystals are toxic within the acidic midgut environment of several coleopteran species, particularly those in the family...

  8. Effect of chemical additives on Bacillus thuringiensis (Bacillales: Bacillaceae) against Plutella xylostella (Lepidoptera: Pyralidae)

    Czech Academy of Sciences Publication Activity Database

    Zhang, L.; Qiu, S.; Huang, T.; Huang, Z.; Xu, L.; Wu, C.; Gelbič, Ivan; Guan, X.

    2013-01-01

    Roč. 106, č. 3 (2013), s. 1075-1080 ISSN 0022-0493 Institutional research plan: CEZ:AV0Z50070508 Keywords : additives * Bacillus thuringiensis * biocontrol Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection Impact factor: 1.605, year: 2013 http://www.bioone.org/doi/pdf/10.1603/EC12288

  9. Resistance: a threat to the insecticidal crystal proteins of Bacillus thuringiensis

    Science.gov (United States)

    Leah S. Bauer

    1995-01-01

    Insecticidal crystal proteins (also known as d-endotoxins) synthesized by the bacterium Bacillus thuringiensis Berliner (Bt) are the active ingredient of various environmentally friendly insecticides that are 1) highly compatible with natural enemies and other nontarget organisms due to narrow host specificity, 2) harmless to vertebrates, 3) biodegradable in the...

  10. A new formulation of Bacillus thuringiensis: UV protection and sustained release mosquito larvae studies

    Czech Academy of Sciences Publication Activity Database

    Zhang, L.; Zhang, X.; Zhang, Y.; Wu, S.; Gelbič, Ivan; Xu, L.; Guan, X.

    2016-01-01

    Roč. 6, DEC 22 (2016), č. článku 39425. ISSN 2045-2322 Institutional support: RVO:60077344 Keywords : Bacillus thuringiensis * pest control * UV protection Subject RIV: EE - Microbiology, Virology Impact factor: 4.259, year: 2016 http://www.nature.com/articles/srep39425

  11. Potato expressing beetle-specific Bacillus thuringiensis Cry3Aa toxin reduces performance of a moth

    Czech Academy of Sciences Publication Activity Database

    Hussein, H. M.; Habuštová, Oxana; Turanli, Ferit; Sehnal, František

    2006-01-01

    Roč. 32, č. 1 (2006), s. 1-13 ISSN 0098-0331 R&D Projects: GA ČR(CZ) GA522/02/1507 Institutional research plan: CEZ:AV0Z50070508 Keywords : Bacillus thuringiensis * Spodoptera littoralis * Leptinotarsa decemlineata Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection Impact factor: 1.896, year: 2006

  12. Characterization of Baculovirus Insecticides Expressing Tailored Bacillus thuringiensis CryIA(b) Crystal Proteins

    NARCIS (Netherlands)

    Martens, John W M; Knoester, Marga; Weijts, Franci; Groffen, Sander J A; Hu, Zhihong; Bosch, Dirk; Vlak, Just M.

    1995-01-01

    Full-length, truncated, and mature forms of the CryIA(b) insecticidal crystal protein gene of Bacillus thuringiensis were engineered into the p10 locus of Autographa californica nuclear polyhedrosis virus (AcNPV). A signal sequence of Heliothis virescens juvenile hormone esterase was introduced at

  13. Laboratory Assessment of the Effects of Bacillus thuringiensis on Native Lepidoptera

    Science.gov (United States)

    John W. Peacock; Dale F. Schweitzer; Jane L. Carter; Normand R. Dubois

    1998-01-01

    The effect of 2 formulations of Bacillus thuringiensis subsp. kurstaki (Foray 48B and Dipel 8AF) was evaluated on 42 species of native Lepidoptera in laboratory bioassays using instars that are present in the field at the time of gypsy moth suppression applications. Mortality was significant for 27 of the 42 species evaluated...

  14. Laboratory and field studies on the effects of Bacillus thuringiensis on non-target lepidoptera

    Science.gov (United States)

    John Peacock; Stephen Talley; Taylor Williams; Richard. Reardon

    1992-01-01

    Bacillus thuringiensis (B.t.) is one of the insecticides considered effective for suppression of gypsy moth infestations, and it is considered to one of the most selective in terms of its effects on other insects. Although B.t. is touted to be "environmentally safe", there is a paucity of field data to support this claim, particularly as...

  15. Use of spent mushroom substrate for production of Bacillus thuringiensis by solid-state fermentation

    Czech Academy of Sciences Publication Activity Database

    Wu, S.; Lan, Y.; Huang, D.; Peng, Y.; Huang, Z.; Xu, L.; Gelbič, Ivan; Carballar-Lejarazu, R.; Guan, X.; Zhang, L.; Zou, S.

    2014-01-01

    Roč. 107, č. 1 (2014), s. 137-143 ISSN 0022-0493 Institutional support: RVO:60077344 Keywords : Bacillus thuringiensis * spent mushroom substrate * solid-state fermentation Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection Impact factor: 1.506, year: 2014 http://www.bioone.org/doi/pdf/10.1603/EC13276

  16. Screen of Bacillus thuringiensis toxins for transgenic rice to control Sesamia inferens and Chilo suppressalis

    Science.gov (United States)

    Transgenic rice to control stem borer damage is under development in China. To assess the potential of Bacillus thuringiensis (Bt) transgenes in stem borer control, the toxicity of five Bt protoxins (Cry1Aa, Cry1Ab, Cry1Ac, Cry1Ba and Cry1Ca) against two rice stem borers, Sesamia inferens (pink stem...

  17. Biological activity of Bacillus thuringiensis (Bacillales: Bacillaceae) chitinase against Caenorhabditis elegans (Rhabditida: Rhabditidae)

    Czech Academy of Sciences Publication Activity Database

    Zhang, L.; Yu, J.; Xie, Y.; Lin, H.; Huang, Z.; Xu, L.; Gelbič, Ivan; Guan, X.

    2014-01-01

    Roč. 107, č. 2 (2014), s. 551-558 ISSN 0022-0493 Institutional support: RVO:60077344 Keywords : Bacillus thuringiensis * Caenorhabditis elegans * chitinase Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection Impact factor: 1.506, year: 2014 http://www.bioone.org/doi/ pdf /10.1603/EC13201

  18. The occurrence of Photorhabdus-like toxin complexes in Bacillus thuringiensis

    Science.gov (United States)

    Recently, genomic sequencing of a Bacillus thuringiensis (Bt) isolate from our collection revealed the presence of an apparent operon encoding an insecticidal toxin complex (Tca) similar to that first described from the entomopathogen Photorhabdus luminescens. To determine whether these genes are w...

  19. Characterization of cry1Cb3 and cry1Fb7 from Bacillus thuringiensis subsp. galleriae

    Czech Academy of Sciences Publication Activity Database

    Huang, T.; Xiao, Y.; Pan, J.; Zhang, L.; Gelbič, Ivan; Guan, X.

    2015-01-01

    Roč. 10, č. 1 (2015), s. 521-528 ISSN 2391-5412 Institutional support: RVO:60077344 Keywords : Bacillus thuringiensis subsp. galleriae * PCR-RFLP * cloning Subject RIV: EB - Genetics ; Molecular Biology http://www.degruyter.com/view/j/biol.2015.10.issue-1/biol-2015-0054/biol-2015-0054.xml

  20. Translocation and insecticidal activity of Bacillus thuringiensis living inside of plants.

    Science.gov (United States)

    Monnerat, Rose Gomes; Soares, Carlos Marcelo; Capdeville, Guy; Jones, Gareth; Martins, Erica Soares; Praça, Lilian; Cordeiro, Bruno Arrivabene; Braz, Shélida Vasconcelos; dos Santos, Roseane Cavalcante; Berry, Colin

    2009-07-01

    The major biological pesticide for the control of insect infestations of crops, Bacillus thuringiensis was found to be present naturally within cotton plants from fields that had never been treated with commercial formulations of this bacterium. The ability of B. thuringiensis to colonize plants as an endophyte was further established by the introduction of a strain marked by production of green fluorescent protein (GFP). After inoculation of this preparation close to the roots of cotton and cabbage seedlings, GFP-marked bacteria could be re-isolated from all parts of the plant, having entered the roots and migrated through the xylem. Leaves taken from the treated plants were able to cause toxicity when fed to the Lepidoptera Spodoptera frugiperda (cotton) and Plutella xylostella (cabbage). These results open up new horizons for understanding the natural ecology and evolution of B. thuringiensis and use of B. thuringiensis in insect control. Journal compilation © 2009 Society for Applied Microbiology and Blackwell Publishing Ltd. No claim to original Brazilian government works.

  1. Effect of Bacillus thuringiensis parasporal toxin on stimulating of IL-2 and IL-5 cytokines production

    Directory of Open Access Journals (Sweden)

    Marzieh Soleimany

    2018-03-01

    Full Text Available Introduction:Bacillus thuringiensis, is a Gram-positive spore-forming bacterium that produces crystalline parasporal protein (Cry during sporulation. Some of these Cry toxins do not show cytotoxicity against insects but they are capable to kill some human and animal cancer cells. The aim of this study was to verify whether cytocidal parasporal of B thuringiensis strains have immunostimulatory activity on human peripheral blood mononuclear cells (PBMNC and to evaluate the ability of IL-2 and IL-5 production. Materials and methods: B. thuringiensis toxin with cytocidal activity was isolated and treated with proteinase K. PBMNC was cultured and treated with activated crystal proteins. We evaluated the ability of different cytokines production with Flow Cytometry. Results: In this study, immune stimulatory toxins Cry1 were distinguished. This toxin can stimulate production of cytokines IL-2 and stop production of IL-5. Discussion and conclusion: According to anti-cancer effect of B. thuringiensis toxins and also immune stimulatory effect, with more research these toxins can be introduced as immunotherapy drug in cancer treatment.

  2. Investigation of Cytocidal Activity of Bacillus Thuringiensis Parasporal Toxin on CCRF-CEM Cell Line

    Directory of Open Access Journals (Sweden)

    Elham Moazamian

    2013-03-01

    Full Text Available Background & Objective: Parasporin is a parasporal protein of Bacillus thuringiensis and exhibits special cytocidal activity against human cancer cells. Similar to other insecticidal Bacillus thuringiensis crystal toxins, parasporin shows target specificity and damages the cellular membrane. In this study, different strains of Bacillus thuringiensis isolated from various regions of Iran and their cytocidal activity against CCRF-CEM cell line and human erythrocyte were investigated.   Materials & Methods: Fifty soil samples were collected from different Iranian provinces, and characterization was performed based on protein crystal morphology by phase-contrast microscope and variations of Cry protein toxin using SDS-PAGE. After parasporin was processed with proteinase K, the active form was produced and protein activity on the cell line was evaluated. Results: Parasporal inclusion proteins showed different cytotoxicity against acute lymphoblastic leukemia cells (ALL, but not against normal lymphocyte. Isolated parasporin demonstrated no hemolytic activity against human erythrocyte. It appears that these proteins have the ability to differentiate between normal lymphocytes and leukemia cells and have specific receptors on specific cancer cell lines. Conclusion: Our results provide evidence that the parasporin-producing organism is a common member in Bacillus thuringiensis populations occurring in the natural environments of Iran.

  3. IMPACT OF BT ( BACILLUS THURINGIENSIS ) CROPS ON BAT ACTIVITY IN SOUTH TEXAS AGROECOSYSTEMS

    Science.gov (United States)

    The widespread adoption of transgenic insecticidal crops raises concerns that nontarget species may be harmed and food webs disrupted. The goal of this research is to determine how transgenic Bt (Bacillus thuringiensis) crops impact the activity of Brazilian freetailed bats (Tada...

  4. Regulation by gut bacertia of immune response, Bacillus thuringiensis susceptibility and hemolin expression in Plodia interpunctella

    Science.gov (United States)

    Plodia interpunctella (Hübner) is an important stored grain insect pest worldwide, and the first lepidopteran with reported resistance to Bacillus thuringiensis (Bt) toxins. Since gut bacteria may affect Bt insecticidal activity, we determined whether P. interpunctella lacking gut enterobacteria had...

  5. Recent field experiences with Bacillus thuringiensis in Canada and research needs

    Science.gov (United States)

    Oswald N. Morris

    1985-01-01

    The CANUSA working group on the use of B.t. against the spruce budworm has prepared a document entitled "Guidelines for the operational use of Bacillus thuringiensis (B.t.) against the spruce budworm" following six years of extensive cooperative field trials in Canada and the U.S.A. (Morris et al 1984). The document summarized below (Table...

  6. Kelimpahan Arthropoda Karnivora di Pertanaman Padi Ratun di Sawah Lebak yang Diaplikasikan Bioinsektisida Bacillus Thuringiensis

    OpenAIRE

    Sunariah, Fila; Herlinda, Siti; Windusari, Yuanita

    2016-01-01

    Kelimpahan Arthropoda karnivora di pertanaman padi ratun di sawah lebak yang diaplikasikan bioinsektisida Bacillus thuringiensis telah dilakukan di sawah lebak Pemulutan, Ogan Ilir Sumatera Selatan selama Agustus-Oktober 2013. Penelitian bertujuan untuk mengetahui kelimpahan Arthropoda karnivora padi ratun yang diberi aplikasi Bacillus thurngiensis dan tanpa diberi aplikasi bioinsektisida. Pengambilan sampel spesies Arthropoda dilakukan dengan menggunakan jaring serangga pada tajuk tanaman pa...

  7. Bacillus thuringiensis toxins trigger receptor shedding from gypsy moth midgut cells

    Science.gov (United States)

    Algimantas P. Valaitis

    2007-01-01

    The mechanism of action of the Cry1 insecticidal proteins produced by Bacillus thuringiensis (Bt) begins with the processing of these proteins in the larval gut. After proteolytic activation, the Bt toxins bind to specific midgut receptors and insert into the membrane of the gut epithelial cells, causing insect death.

  8. Response of the Cottonwood Leaf Beetle (Coleoptera: Chrysomelidae) to Bacillus thuringiensis var. san diego

    Science.gov (United States)

    Leah S. Bauer

    1990-01-01

    A standardized laboratory bioassay was used to quantify the lethal and sub-lethal responses of larval and adult cottonwood leaf beetles, Chrysomela scripta F., to Bacillus thuringiensis var. san diego, formulated as M-One standard powder (Mycogen Corporation, San Diego). The median lethal concentration (LC

  9. Assessment of microbial larvicide spraying with Bacillus thuringiensis israelensis, for the prevention of malaria.

    Science.gov (United States)

    Kinde-Gazard, D; Baglo, T

    2012-03-01

    The aim of this study was to assess the contribution of microbial larvicide spraying, Bacillus thuringiensis israelensis, as prevention strategy against malaria. An experimental study consisted in spraying B. thuringiensis israelensis in a district during 1 year has been conducted. Another district (control) was not sprayed. Eight hundred and two children were evaluated, thick drop and swab examination was performed for those presenting with fever. The larval density was calculated in their habitats as well as larvicide remanence. Capture of mosquitoes with human bait allowed determining human exposure to bites at night, and identifying anopheles after dissection. The incidence of pediatric malaria was 13.8% in the sprayed district and 31.4% in the control district. The parasitic load ranged from 2000 to 42,000 parasites/μL in the sprayed district and 2000 to 576,000 parasites/μL in the control district. Plasmodium falciparum was the most frequent (97.8%) plasmodial species. In the control district, at least 20 larvae by liter of water were counted; anopheles larvae were found in 11 larval habitats out of 15 (73.33%). The human exposure to anopheles bites at night was 14.25 in the sprayed district and 33.13 in the control district. The remanence of B. thuringiensis israelensis was estimated at 9 days in the sprayed district. The larvicide B. thuringiensis israelensis may be used in vector control strategy for the prevention of malaria. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  10. Effects of Bacillus thuringiensis CRY1A(c) δ-endotoxin on growth ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-01-04

    Jan 4, 2010 ... The recent introduction of Bt maize and Bt cotton transgenic crops into Africa has raised concerns on their potential short and long-term ecological effects on the environment. The effects of Bacillus thuringiensis (Bt) Cry1A(c) δ-endotoxin on the growth, nodulation and productivity of two leguminous.

  11. Effects of ensiling of Bacillus thuringiensis (Bt) maize (MON810) on ...

    African Journals Online (AJOL)

    The study investigated the degradation of the Bt protein (Cry1Ab) in Bt maize during ensiling and chemical composition of the silage. Two laboratory studies were conducted at the University of Fort Hare. One Bacillus thuringiensis (Bt) maize cultivar (DKC80-12B) and its isoline (DKC80-10) in the 2008/2009 study and two Bt ...

  12. Effects of Bacillus thuringiensis CRY1A(c) d-endotoxin on growth ...

    African Journals Online (AJOL)

    The recent introduction of Bt maize and Bt cotton transgenic crops into Africa has raised concerns on their potential short and long-term ecological effects on the environment. The effects of Bacillus thuringiensis (Bt) Cry1A(c) d-endotoxin on the growth, nodulation and productivity of two leguminous plants grown in clay soil ...

  13. Serovars of Salmonella isolated from Danish turkeys between 1995 and 2000 and their antimicrobial resistance

    DEFF Research Database (Denmark)

    Pedersen, Karl; Hansen, H.C.; Jørgensen, J.C.

    2002-01-01

    , florfenicol, or amoxycillin with clavulanic acid, only 24 isolates were resistant to two or more compounds in various combinations of up to six compounds; one Salmonella Havana isolate was resistant to six compounds. Six isolates were serovar Typhimurium, but none of them belonged to phage type DT104....

  14. Multiple roles of putrescine and spermidine in stress resistance and virulence of Salmonella enterica serovar Typhimurium

    DEFF Research Database (Denmark)

    Cartas Espinel, Irene; Guerra, Priscila Regina; Jelsbak, Lotte

    2016-01-01

    Polyamines (putrescine and spermidine) are small-cationic amines ubiquitous in nature and present in most living cells. In recent years they have been linked to virulence of several human pathogens including Shigella spp and Salmonella enterica serovar Typhimurium (S. Typhimurium). Central to S...

  15. Comparative proteome analysis of Chlamydia trachomatis serovar A, D and L2

    DEFF Research Database (Denmark)

    Shaw, Allan C; Gevaert, Kris; Demol, Hans

    2002-01-01

    generated novel data on genetic variability as indicated by electrophoretic variation and potentially important examples of serovar specific differences in protein abundance. The availability of the complete genome made it feasible to map and to identify proteins of C. trachomatis on a large scale...

  16. Chlamydia trachomatis serovar G infection in a bisexual male with urethritis.

    Science.gov (United States)

    Rawre, Jyoti; Dhawan, Benu; Saigal, Karnika; Khanna, Neena

    2016-01-01

    We report a case of Chlamydia trachomatis serovar G urogenital tract infection in a 33-year-old human immunodeficiency virus-1 (HIV-1) seropositive Indian bisexual male. This case highlights the emergence of a new serovar in India. The patient was tested positive for C. trachomatis by both cryptic plasmid and omp A gene polymerase chain reaction (PCR). On further characterization using polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) and omp A gene sequencing, the strain was found to be C. trachomatis serovar G. His spouse was also found to be infected with C. trachomatis serovar G. Phylogenetic analysis was performed on the clinical isolates obtained from both partners and were found to be identical to the isolates available in GenBank. The sexual network could not be traced further. Detection of a new genotype suggests importation of a new strain into the population probably by sexual contact with a person from a geographical area where the strain is common. Identifying circulating genotypes in the community can assist in developing strategies for improved sexually transmitted disease control.

  17. Characterization of native and recombinant 75-kilodalton immunogens from Chlamydia trachomatis serovar L2

    DEFF Research Database (Denmark)

    Birkelund, Svend; Lundemose, AG; Christiansen, Gunna

    1989-01-01

    A 75-kilodalton (kDa) immunogen from Chlamydia trachomatis serovar L2 was characterized. The 75-kDa protein was localized in the cytoplasm of chlamydiae and was shown to be a protein synthesized early in the developmental cycle of chlamydiae. A gene library was made by the recombinant DNA technique...

  18. Characterization of a linear epitope on Chlamydia trachomatis serovar L2 DnaK-like protein

    DEFF Research Database (Denmark)

    Ozkokmen, D; Birkelund, Svend; Christiansen, Gunna

    1994-01-01

    A cytoplasmic 75-kDa immunogen from Chlamydia trachomatis serovar L2 has previously been characterized as being similar to the Escherichia coli heat shock protein DnaK. We have localized a linear epitope for one monoclonal antibody specific for C. trachomatis DnaK. By use of a recombinant DNA...

  19. Extremely Drug-Resistant Salmonella enterica Serovar Senftenberg Infections in Patients in Zambia

    DEFF Research Database (Denmark)

    Hendriksen, Rene S.; Joensen, Katrine Grimstrup; Lukwesa-Musyani, Chileshe

    2013-01-01

    Two cases of extremely drug-resistant Salmonella enterica serovar Senftenberg isolated from patients in Zambia were investigated by utilizing MIC determinations and whole-genome sequencing. The isolates were resistant to, and harbored genes toward, nine drug classes, including fluoroquinolones an...... and extended-spectrum cephalosporins, contained two plasmid replicons, and differed by 93 single-nucleotide polymorphisms....

  20. Antimicrobial drug susceptibility of Leptospira interrogans serovar hardjo isolated from cattle.

    Science.gov (United States)

    Prescott, J F; Nicholson, V M

    1988-01-01

    The susceptibility to commonly used drugs of 18 isolates of Leptospira hardjo from the kidneys of feedlot cattle from different sources was determined quantitatively. All isolates were susceptible to penicillin G, ampicillin, tetracycline, erythromycin and streptomycin. Susceptibility to sulphamethazine was ambiguous. No drug resistance was detected and the results were similar to those described for other serovars. PMID:3370565

  1. Tetracycline promotes the expression of ten fimbrial operons in specific Salmonella enterica serovar Typhimurium isolates

    Science.gov (United States)

    Multidrug-resistant (MDR) Salmonella is associated with increased morbidity in humans and presents an important food safety concern. Antibiotic resistance among isolates of Salmonella enterica serovar Typhimurium has become especially prevalent as over 27 per cent of isolates from humans in the Unit...

  2. Thioridazine protects the mouse from a virulent infection by Salmonella enterica serovar Typhimurium 74

    DEFF Research Database (Denmark)

    Dasgupta, Asish; Mukherjee, Sayanti; Chaki, Shaswati

    2010-01-01

    When administered to mice at doses of 100microg/mouse and 200microg/mouse, thioridazine (TDZ) significantly protected animals from the lethality produced by a virulent strain of Salmonella enterica serovar Typhimurium and reduced the number of bacteria retrieved from the spleen, liver and heart...

  3. First report of iliacus abscess caused by Salmonella enterica serovar Othmarschen.

    Science.gov (United States)

    Jha, Babita; Kim, Choon-Mee; Kim, Dong-Min; Chung, Jong-Hoon; Yoon, Na-Ra; Jha, Piyush; Kim, Seok Won; Jang, Sook Jin; Kim, Seon Gyeong; Chung, Jae Keun

    2016-02-01

    The non-typhoidal bacterium Salmonella enterica subspecies enterica serovar Othmarschen (Salmonella Othmarschen) is a rare human pathogen. Abscess formation due to non-typhoidal Salmonella infections is a very rare complication in this antibiotic era. We report the first case of iliacus abscess after a short period of gastroenteritis which was caused by non-typhoidal Salmonella enterica belonging to group C1, serovar Othmarschen in a patient without any underlying conditions. A young female presented in our hospital complaining of pain in right hip joint area. She gave a history of watery diarrhea 3 days before the onset of pain. On examination the patient was ill-looking and there was tenderness in the right hip joint area. S. enterica was identified using 16S rRNA gene amplification by PCR and serotyped to be serovar Othmarschen from the pus sample of iliacus abscess. This is the first reported case of iliacus abscess due to Salmonella serover Othmarschen infection. Our case suggests that S. enterica serovar Othmarschen can cause severe focal infections associated with gastroenteritis. The literature on the rare association of Salmonella enterica and abscess formation is reviewed. Copyright © 2015 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  4. New flagellin gene for Salmonella enterica serovar Typhi from the East Indonesian archipelago

    NARCIS (Netherlands)

    Hatta, Mochammad; Sultan, Andi R.; Pastoor, Rob; Smits, Henk L.

    2011-01-01

    Phase variation is a property unique of some Salmonella enterica serovar Typhi strains from Indonesia. Salmonella Typhi isolates from Indonesia have been described that in addition to the phase 1 Hd flagellin gene contain a second flagellin gene named z66. S. Typhi isolates from Indonesia with a

  5. Salmonella gene rma (ramA) and multiple-drug-resistant Salmonella enterica serovar typhimurium

    NARCIS (Netherlands)

    Straaten, van T.; Janssen, R.; Mevius, D.J.; Dissel, van J.T.

    2004-01-01

    MarA and its homologue, RamA, have been implicated in multidrug resistance (MDR). RamA overexpression in Salmonella enterica serovar Typhimurium and Escherichia coli conferred MDR independently of marA. Inactivation of ramA did not affect the antibiotic susceptibilities of wild-type S. enterica

  6. New Leptospira serovar Sokoine of serogroup Icterohaemorrhagiae from cattle in Tanzania

    NARCIS (Netherlands)

    Mgode, G. F.; Machang'u, R. S.; Goris, M. G.; Engelbert, M.; Sondij, S.; Hartskeerl, R. A.

    2006-01-01

    The prevalence of leptospirosis is generally high in domestic animals and rodents in Tanzania. Identification of Leptospira isolates from cattle was carried out to establish prevalent Leptospira serovars. Serological typing was done based on monoclonal antibodies and the standard cross-agglutination

  7. Natural surface coating to inactivate Salmonella enterica Serovar Typhimurium and maintain quality of cherry tomatoes

    Science.gov (United States)

    The objectives of the present study were to investigate the effectiveness of zein-based coatings in reducing populations of Salmonella enterica serovar Typhimurium and preserving quality of cherry tomatoes. Tomatoes were inoculated with a cocktail of S. Typhimurium LT2 plus three mutants on the smoo...

  8. Potential International Spread of Multidrug-Resistant Invasive Salmonella enterica Serovar Enteritidis

    Science.gov (United States)

    Rodicio, M. Rosario; Guerra, Beatriz; Hopkins, Katie L.

    2012-01-01

    In developing countries, Salmonella enterica serovar Enteritidis causes substantial illness and death, and drug resistance is increasing. Isolates from the United Kingdom containing virulence-resistance plasmids were characterized. They mainly caused invasive infections in adults linked to Africa. The common features in isolates from these continents indicate the role of human travel in their spread. PMID:22709653

  9. Typhaea stercorea (Coleoptera : Mycetophagidae), a carrier of Salmonella enterica serovar Infantis in a Danish broiler house

    DEFF Research Database (Denmark)

    Hald, Birthe; Olsen, A.; Madsen, Mogens

    1998-01-01

    In December 1994, Salmonella enterica serovar Infantis (S. Infantis) was accidentally introduced into a Danish broiler house by stocking an S. Infantis-infected broiler nock of 39,900 day-old chicks. At the time of the study, the infection had persisted through e broiler cycles. Typhaea stercorea...

  10. Multiresistant Salmonella enterica serovar 4,[5],12:i:- in Europe: a new pandemic strain?

    NARCIS (Netherlands)

    Hopkins, K.L.; Kirchner, M.; Guerra, B.; Granier, A.; Lucarelli, C.; Porrero, M.C.; Jakubczak, A.; Threlfall, J.; Mevius, D.J.

    2010-01-01

    A marked increase in the prevalence of S. enterica serovar 4,[5],12:i:- with resistance to ampicillin, streptomycin, sulphonamides and tetracyclines (R-type ASSuT) has been noted in food-borne infections and in pigs/pig meat in several European countries in the last ten years. One hundred and

  11. Novel Cell Wall Hydrolase CwlC from Bacillus thuringiensis Is Essential for Mother Cell Lysis.

    Science.gov (United States)

    Chen, Xiaomin; Gao, Tantan; Peng, Qi; Zhang, Jie; Chai, Yunrong; Song, Fuping

    2018-04-01

    In this study, a sporulation-specific gene (tentatively named cwlC ) involved in mother cell lysis in Bacillus thuringiensis was characterized. The encoded CwlC protein consists of an N-terminal N -acetylmuramoyl-l-alanine amidase (Mur N Ac-LAA) domain and a C-terminal amidase02 domain. The recombinant histidine-tagged CwlC proteins purified from Escherichia coli were able to directly bind to and digest the B. thuringiensis cell wall. The CwlC point mutations at the two conserved glutamic acid residues (Glu-24 and Glu-140) shown to be critical for the catalytic activity in homologous amidases resulted in a complete loss of cell wall lytic activity, suggesting that CwlC is an N -acetylmuramoyl-l-alanine amidase. Results of transcriptional analyses indicated that cwlC is transcribed as a monocistronic unit and that its expression is dependent on sporulation sigma factor K (σ K ). Deletion of cwlC completely blocked mother cell lysis during sporulation without impacting the sporulation frequency, Cry1Ac protein production, and insecticidal activity. Taken together, our data suggest that CwlC is an essential cell wall hydrolase for B. thuringiensis mother cell lysis during sporulation. Engineered B. thuringiensis strains targeting cwlC , which allows the crystal inclusion to remain encapsulated in the mother cell at the end of sporulation, may have the potential to become more effective biological control agents in agricultural applications since the crystal inclusion remains encapsulated in the mother cell at the end of sporulation. IMPORTANCE Mother cell lysis has been well studied in Bacillus subtilis , which involves three distinct yet functionally complementary cell wall hydrolases. In this study, a novel cell wall hydrolase, CwlC, was investigated and found to be essential for mother cell lysis in Bacillus thuringiensis CwlC of B. thuringiensis only shows 9 and 21% sequence identity with known B. subtilis mother cell hydrolases CwlB and CwlC, respectively

  12. Transcriptional profile of tomato roots exhibiting Bacillus thuringiensis-induced resistance to Ralstonia solanacearum.

    Science.gov (United States)

    Takahashi, Hideki; Nakaho, Kazuhiro; Ishihara, Takeaki; Ando, Sugihiro; Wada, Takumi; Kanayama, Yoshinori; Asano, Shinichiro; Yoshida, Shigenobu; Tsushima, Seiya; Hyakumachi, Mitsuro

    2014-01-01

    Activation of SA-dependent signaling pathway and suppression of JA-dependent signaling pathway seem to play key roles inB. thuringiensis-induced resistance toR. solanacearumin tomato plants. Bacillus thuringiensis, a well-known and effective bio-insecticide, has attracted considerable attention as a potential biological control agent for the suppression of plant diseases. Treatment of tomato roots with a filter-sterilized cell-free filtrate (CF) of B. thuringiensis systemically suppresses bacterial wilt caused by Ralstonia solanacearum through systemic activation of the plant defense system. Comparative analysis of the expression of the Pathogenesis-Related 1(P6) gene, a marker for induced resistance to pathogens, in various tissues of tomato plants treated with CF on their roots suggested that the B. thuringiensis-induced defense system was activated in the leaf, stem, and main root tissues, but not in the lateral root tissue. At the same time, the growth of R. solanacearum was significantly suppressed in the CF-treated main roots but not in the CF-treated lateral roots. This distinct activation of the defense reaction and suppression of R. solanacearum were reflected by the differences in the transcriptional profiles of the main and lateral tissues in response to the CF. In CF-treated main roots, but not CF-treated lateral roots, the expression of several salicylic acid (SA)-responsive defense-related genes was specifically induced, whereas jasmonic acid (JA)-related gene expression was either down-regulated or not induced in response to the CF. On the other hand, genes encoding ethylene (ET)-related proteins were induced equally in both the main and lateral root tissues. Taken together, the co-activation of SA-dependent signaling pathway with ET-dependent signaling pathway and suppression of JA-dependent signaling pathway may play key roles in B. thuringiensis-induced resistance to R. solanacearum in tomato.

  13. Evaluation of the ERIC-PCR as a probable method to differentiate Avibacterium paragallinarum serovars.

    Science.gov (United States)

    Hellmuth, Julius Eduard; Hitzeroth, Arina Corli; Bragg, Robert Richard; Boucher, Charlotte Enastacia

    2017-06-01

    Infectious coryza, an upper respiratory tract disease in chickens, caused by Avibacterium paragallinarum, leads to huge economic losses. The disease is controlled through vaccination; but vaccination efficacy is dependent on correct identification of the infecting serovar, as limited cross-protection is reported amongst some serovars. Current identification methods include the heamagglutination inhibition test, which is demanding and could be subjective. To overcome this, molecular typing methods proposed are the Multiplex polymerase chain reaction (PCR) and Restriction Fragment Length Polymorphism-PCR, but low reproducibility is reported. Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR has been suggested for molecular groupings of various bacterial species. This study focuses on evaluating the ERIC-PCR as a probable method to differentiate between different Av. paragallinarum serovars by grouping with reference isolates, based on clonal relations. The ERIC-PCR was performed on 12 reference isolates and 41 field isolates originating from South Africa and South America. The data indicate that the ERIC-PCR is not ideal for the differentiation or for molecular typing of Av. paragallinarum serovars, as no correlation is drawn upon comparison of banding patterns of field isolates and reference strains. However, the results do indicate isolates from the same origin sharing unique banding patterns, indicating potential clonal relationship; but when compared to the reference isolates dominant in the specific area, no correlation could be drawn. Furthermore, although the ERIC-PCR serves a purpose in epidemiological studies, it has proved to have little application in differentiating amongst serovars of Av. paragallinarum and to group untyped field strains with known reference strains.

  14. Phenotypic and molecular characterization of Salmonella enterica serovar Sofia, an avirulent species in Australian poultry.

    Science.gov (United States)

    Gan, Emily; Baird, Fiona J; Coloe, Peter J; Smooker, Peter M

    2011-04-01

    Salmonella enterica serovar Sofia (S. Sofia) is often isolated from chickens in Australia. However, despite its high frequency of isolation from chicken and chicken meat products, S. Sofia is rarely associated with animal or human salmonellosis, presumably because this serovar is avirulent in nature. The objective of this work was to investigate the phenotypic and molecular properties of S. Sofia in order to assess its pathogenic potential. Our in vivo studies support the observation that this serovar can colonize tissues, but does not cause disease in chickens. This was further confirmed with tissue culture assays, which showed that the ability of S. Sofia to adhere, invade and survive intracellularly is significantly diminished compared with the pathogenic Salmonella enterica serovar Typhimurium (S. Typhimurium) 82/6915. Molecular analysis of Salmonella pathogenicity islands (SPIs) showed that most of the differences observed in SPI1 to SPI5 of S. Sofia could be attributed to minor changes in the sequences, as indicated by a loss or gain of restriction cleavage sites within these regions. Sequence analysis demonstrated that the majority of virulence genes identified were predicted to encode proteins sharing a high identity (75-100 %) with corresponding proteins from S. Typhimurium. However, a number of virulence genes in S. Sofia have accumulated mutations predicted to affect transcription and/or translation. The avirulence of this serovar is probably not the result of a single genetic change but rather of a series of alterations in a large number of virulence-associated genes. The acquisition of any single virulence gene will almost certainly not be sufficient to restore S. Sofia virulence.

  15. Salmonella Sofia differs from other poultry-associated Salmonella serovars with respect to cell surface hydrophobicity.

    Science.gov (United States)

    Chia, T W R; Fegan, N; McMeekin, T A; Dykes, G A

    2008-12-01

    Salmonella enterica is one of the most important foodborne pathogens. Salmonella enterica subsp. II 4,12:b:- (Salmonella Sofia) is commonly found in Australian poultry. It has been suggested that physicochemical properties such as surface charge and hydrophobicity may affect bacterial attachment to surfaces and their ability to persist in food systems. A possible link between hydrophobicity cell surface charge and persistence of Salmonella from the poultry system was examined. Hydrophobicity of Salmonella Sofia (n = 14), Salmonella Typhimurium (n = 6), Salmonella Infantis (n = 3), and Salmonella Virchow (n = 2) was assayed using hydrophobic interaction chromatography, bacterial adherence to hydrocarbons (BATH), using xylene or hexadecane, and the contact angle method (CAM). Cellular surface charge (CSC) of the isolates was determined using zeta potential measurements. The majority (12 of 14) of Salmonella Sofia isolates were found to be hydrophobic when assayed using BATH with xylene, except isolates S1635 and S1636, and the other serovars were found to be hydrophilic. Salmonella Sofia isolates were not significantly different (P > 0.05) from isolates of other serovars as measured by hydrophobic interaction, BATH with hexadecane, or the CAM. No significant differences (P > 0.05) in zeta potential measurements were observed between isolates. Principal component analysis using results from all four measures of hydrophobicity allowed clear differentiation between isolates of the serovar Salmonella Sofia (except S1635 and S1636) and those of other Salmonella serovars. Differences in physicochemical properties may be a contributing factor to the Salmonella Sofia serovar's ability to attach to surfaces and persist in a food system.

  16. RAP-PCR fingerprinting reveals time-dependent expression of development-related genes following differentiation process of Bacillus thuringiensis

    Czech Academy of Sciences Publication Activity Database

    Huang, T.; Yu, X.; Gelbič, Ivan; Guan, X.

    2015-01-01

    Roč. 61, č. 9 (2015), s. 683-690 ISSN 0008-4166 Institutional support: RVO:60077344 Keywords : Bacillus thuringiensis * development * RNA arbitrarily primed PCR Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.335, year: 2015

  17. Resistance to Bacillus thuringiensis linked with a cadherin transmembrane mutation affecting cellular trafficking in pink bollworm from China

    Science.gov (United States)

    Transgenic crops producing insecticidal proteins from Bacillus thuringiensis (Bt) are cultivated extensively worldwide. However, their benefits are being eroded by increasingly rapid evolution of resistance in pests. In some previously analyzed strains of three major lepidopteran pests, resistance t...

  18. Interactions between Bacillus thuringiensis and parasitoids of late-instar larvae of the spruce budworm (Lepidoptera: Tortricidae)

    NARCIS (Netherlands)

    Schoenmaker, A.; Cusson, M.; Frankenhuyzen, van K.

    2001-01-01

    We investigated interactions between Bacillus thuringiensis Berliner var. kurstaki and parasitoids that attack late instars of the eastern spruce budworm, Choristoneura fumiferana (Clemens). In a petri-dish arena, females of Tranosema rostrale rostrale (Brishke) (Hymenoptera: Ichneumonidae) were

  19. [Genes of insecticidal crystal proteins with dual specificity in Bacillus thuringiensis strains, isolated in the Crimea territory].

    Science.gov (United States)

    Rymar, S Iu; Isakova, I A; Kuznietsova, L M; Kordium, V A

    2006-01-01

    The insecticidal crystal proteins of 15 B. thuringiensis strains, isolated in the Crimea territory that are toxical for some Lepidoptera and Colorado potato beetle larvae were identified by PAGE electrophoresis. Ten strains produced the crystal proteins with high molecular weight (> 120 kD). PCR with use of broad specificity primers and DNA of these B. thuringiensis strains as template demonstrated the specific PCR products (1000 bp). Amplified DNA fragments were cloned and sequenced. The nucleotide sequence analysis revealed that the genomes of ten strains of B. thuringiensis carried Cry1B genes, which are responsible for production of the insecticidal crystal proteins with dual specificity. The influence of the solubilization conditions on the structure and toxicity of Cry1B protein for Colorado potato beetle larvae was shown. The dual toxicity of studied B. thuringiensis strains is explained by the Cry1B genes presence in their genomes. These strains may be used to develop the broad specificity bioinsecticides.

  20. Microimaging of Bacillus thuringiensis Toxin-binding proteins in gypsy moth larval gut using confocal fluorescence microscopy

    Science.gov (United States)

    Daniel J. Krofcheck; Algimantas P. Valaitis

    2010-01-01

    After ingestion by susceptible insect larvae, Bacillus thuringiensis (Bt) insecticidal proteins bind to the brush border membranes of gut epithelial cells and disrupt the integrity of the plasma membrane by forming...

  1. Screening and identification of a Bacillus thuringiensis strain S1/4 with large and efficient insecticidal activities.

    OpenAIRE

    Jaoua, Samir; Sellami, Sameh; Zghal, Taheni; Cherif, Maroua; Zalila-Kolsi, Imen; Jaoua, Samir; Jamoussi, Kaïs

    2013-01-01

    The bacterium Bacillus thuringiensis was recognized for its entomopathogenic activities related to Cry and Cyt proteins forming the δ-endotoxins and some extracellular activities like the vegetative insecticidal proteins (VIP) and Cry1I. These activities may act specifically against diverse organisms and some of them typically characterize each strain. Here, we screened a set of 212 B. thuringiensis strains to search the higher insecticidal activities. These strains had bipyramidal and cubic ...

  2. Evaluation of Bacillus thuringiensis Pathogenicity for a Strain of the Tick, Rhipicephalus microplus, Resistant to Chemical Pesticides

    OpenAIRE

    Fern?ndez-Ruvalcaba, Manuel; Pe?a-Chora, Guadalupe; Romo-Mart?nez, Armando; Hern?ndez-Vel?zquez, V?ctor; de Parra, Alejandra Bravo; De La Rosa, Diego P?rez

    2010-01-01

    The pathogenicity of four native strains of Bacillus thuringiensis against Rhipicephalus (Boophilus) microplus (Canestrine) (Acari: Ixodidae) was evaluated. A R. microplus strain that is resistant to organophosphates, pyrethroids, and amidines, was used in this study. Adult R. microplus females were bioassayed using the immersion test of Drummond against 60 B. thuringiensis strains. Four strains, GP123, GP138, GP130, and GP140, were found to be toxic. For the immersion test, the total protein...

  3. Molecular and serological characterization of Leptospira interrogans serovar Canicola isolated from dogs, swine, and bovine in Brazil

    NARCIS (Netherlands)

    Miraglia, Fabiana; de Morais, Zenaide M.; Dellagostin, Odir A.; Seixas, Fabiana K.; Freitas, Julio C.; Zacarias, Francielle G. S.; Delbem, Adina C.; Ferreira, Thaís S. P.; Souza, Gisele O.; Hartskeerl, Rudy A.; Vasconcellos, Silvio A.; Moreno, Andrea M.

    2012-01-01

    The identification of Leptospira clinical isolates through genotyping and serotyping, besides the recognition of its reservoirs, are important tools for understanding the epidemiology of leptospirosis, and they are also keys for identifying new species and serovars. Fourteen clinical isolates from

  4. Intragastric immunization with recombinant Lactobacillus casei expressing flagellar antigen confers antibody-independent protective immunity against Salmonella enterica serovar Enteritidis

    NARCIS (Netherlands)

    Kajikawa, A.; Satoh, E.; Leer, R.J.; Yamamoto, S.; Igimi, S.

    2007-01-01

    A recombinant Lactobacillus casei expressing a flagellar antigen from Salmonella enterica serovar Enteritidis was constructed and evaluated as a mucosal vaccine. Intragastric immunization of the recombinant strain conferred protective immunity against Salmonella infection in mice. This immunization

  5. 40 CFR 174.532 - Bacillus thuringiensis eCry3.1Ab protein in corn; temporary exemption from the requirement of a...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus thuringiensis eCry3.1Ab... Bacillus thuringiensis eCry3.1Ab protein in corn, in or on the food and feed commodities of corn; corn... Bacillus thuringiensis eCry3.1Ab protein in corn is used as a plant-incorporated protectant in accordance...

  6. Evaluation de l'efficacité de la Bacillus thuringiensis contre les larves et imagos de Andrector ruficornis sur les plants de Solanum tuberosum au Cameroun

    OpenAIRE

    Ouzounov, IS.; Omokolo, ND.; Ambang, Z.

    2002-01-01

    Evaluation of the Efficiency of Bacillus thuringiensis on Larvae and Adults of Andrector ruficornis on Solanum tuberosum plants in Cameroon. The efficiency of Bacillus thuringiensis as an insecticide on the larvae and adults of A. ruficornis (a leaf eating pest) was investigated on Solanum tuberosum plants grown in the field. The results show that, one hour following the treatment of A. ruficornis with a 1.4 g/l suspension of Bacillus thuringiensis, larvae and adults are paralysed on the plan...

  7. Integrative analysis of Salmonellosis in Israel reveals association of Salmonella enterica Serovar 9,12:l,v:- with extraintestinal infections, dissemination of endemic S. enterica Serovar Typhimurium DT104 biotypes, and severe underreporting of outbreaks.

    Science.gov (United States)

    Marzel, Alex; Desai, Prerak T; Nissan, Israel; Schorr, Yosef Ilan; Suez, Jotham; Valinsky, Lea; Reisfeld, Abraham; Agmon, Vered; Guard, Jean; McClelland, Michael; Rahav, Galia; Gal-Mor, Ohad

    2014-06-01

    Salmonella enterica is the leading etiologic agent of bacterial food-borne outbreaks worldwide. This ubiquitous species contains more than 2,600 serovars that may differ in their host specificity, clinical manifestations, and epidemiology. To characterize salmonellosis epidemiology in Israel and to study the association of nontyphoidal Salmonella (NTS) serovars with invasive infections, 48,345 Salmonella cases reported and serotyped at the National Salmonella Reference Center between 1995 and 2012 were analyzed. A quasi-Poisson regression was used to identify irregular clusters of illness, and pulsed-field gel electrophoresis in conjunction with whole-genome sequencing was applied to molecularly characterize strains of interest. Three hundred twenty-nine human salmonellosis clusters were identified, representing an annual average of 23 (95% confidence interval [CI], 20 to 26) potential outbreaks. We show that the previously unsequenced S. enterica serovar 9,12:l,v:- belongs to the B clade of Salmonella enterica subspecies enterica, and we show its frequent association with extraintestinal infections, compared to other NTS serovars. Furthermore, we identified the dissemination of two prevalent Salmonella enterica serovar Typhimurium DT104 clones in Israel, which are genetically distinct from other global DT104 isolates. Accumulatively, these findings indicate a severe underreporting of Salmonella outbreaks in Israel and provide insights into the epidemiology and genomics of prevalent serovars, responsible for recurring illness. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  8. Multidrug-Resistant Salmonella enterica Serovar Muenchen from Pigs and Humans and Potential Interserovar Transfer of Antimicrobial Resistance

    OpenAIRE

    Gebreyes, Wondwossen A.; Thakur, Siddhartha

    2005-01-01

    Salmonella serovars are important reservoirs of antimicrobial resistance. Recently, we reported on multidrug-resistant (MDR) Salmonella enterica serovar Typhimurium strains among pigs with resistance to ampicillin, kanamycin, streptomycin, sulfamethoxazole, and tetracycline (resistance [R] type AKSSuT) and resistance to amoxicillin-clavulanic acid, ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (R type AxACSSuT). In the present study, 67 isolates (39 from humans...

  9. Leptospira Serovars for Diagnosis of Leptospirosis in Humans and Animals in Africa: Common Leptospira Isolates and Reservoir Hosts

    Science.gov (United States)

    Mgode, Georgies F.; Machang’u, Robert S.; Mhamphi, Ginethon G.; Katakweba, Abdul; Mulungu, Loth S.; Durnez, Lies; Leirs, Herwig; Hartskeerl, Rudy A.; Belmain, Steven R.

    2015-01-01

    The burden of leptospirosis in humans and animals in Africa is higher than that reported from other parts of the world. However, the disease is not routinely diagnosed in the continent. One of major factors limiting diagnosis is the poor availability of live isolates of locally circulating Leptospira serovars for inclusion in the antigen panel of the gold standard microscopic agglutination test (MAT) for detecting antibodies against leptospirosis. To gain insight in Leptospira serovars and their natural hosts occurring in Tanzania, concomitantly enabling the improvement of the MAT by inclusion of fresh local isolates, a total of 52 Leptospira isolates were obtained from fresh urine and kidney homogenates, collected between 1996 and 2006 from small mammals, cattle and pigs. Isolates were identified by serogrouping, cross agglutination absorption test (CAAT), and molecular typing. Common Leptospira serovars with their respective animal hosts were: Sokoine (cattle and rodents); Kenya (rodents and shrews); Mwogolo (rodents); Lora (rodents); Qunjian (rodent); serogroup Grippotyphosa (cattle); and an unknown serogroup from pigs. Inclusion of local serovars particularly serovar Sokoine in MAT revealed a 10-fold increase in leptospirosis prevalence in Tanzania from 1.9% to 16.9% in rodents and 0.26% to 10.75% in humans. This indicates that local serovars are useful for diagnosis of human and animal leptospirosis in Tanzania and other African countries. PMID:26624890

  10. Isolation of Leptospira santarosai, serovar guaricura from buffaloes (Bubalus bubalis in Vale do Ribeira, São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Vasconcellos Silvio A.

    2001-01-01

    Full Text Available In April 1998 urine samples from adult female buffaloes were collected in a farm located in Registro, Vale do Ribeira, São Paulo State, Brazil. The urine samples obtained after furosemide injection were immediately transported to the laboratory in liquid modified EMJH medium and seeded, by the serial dilution technique, into Fletcher's or modified EMJH-0.2% agar, both of them with 5-fluorouracil 100mg/mL. The intraperitoneoum inoculation of 0.5 mL was also performed with each urine sample in young, adult hamsters (Mesocricetus auratus. All samples seeded directly in culture medium were contaminated. The hamsters did not show any sign of disease and were killed at the 21st post inoculation day. At this time kidney cultures of these animals were performed and from one of them, one leptospira strain (M04-98 was isolated, identified as belonging to serogroup Sejroe by Microscopic Agglutination Test (MAT with a panel of 36 rabbit sera against serovars representative for the pathogenic serogroups. Subsequently, MAT was carried out with antisera against the 19 reference strains of serogroup Sejroe, revealing a close relationship with serovar guaricura. Afterwards the MAT was done with a panel of 18 monoclonal antibodies representative for serovars of serogroup Sejroe. The histogram closely resembled that of serovar guaricura. So Cross Agglutination Absorption Test (CAAT was carried out with the buffalo isolate and serovar guaricura, supporting the relationship between the buffalo isolate and serovar guaricura.

  11. Leptospira Serovars for Diagnosis of Leptospirosis in Humans and Animals in Africa: Common Leptospira Isolates and Reservoir Hosts.

    Science.gov (United States)

    Mgode, Georgies F; Machang'u, Robert S; Mhamphi, Ginethon G; Katakweba, Abdul; Mulungu, Loth S; Durnez, Lies; Leirs, Herwig; Hartskeerl, Rudy A; Belmain, Steven R

    2015-12-01

    The burden of leptospirosis in humans and animals in Africa is higher than that reported from other parts of the world. However, the disease is not routinely diagnosed in the continent. One of major factors limiting diagnosis is the poor availability of live isolates of locally circulating Leptospira serovars for inclusion in the antigen panel of the gold standard microscopic agglutination test (MAT) for detecting antibodies against leptospirosis. To gain insight in Leptospira serovars and their natural hosts occurring in Tanzania, concomitantly enabling the improvement of the MAT by inclusion of fresh local isolates, a total of 52 Leptospira isolates were obtained from fresh urine and kidney homogenates, collected between 1996 and 2006 from small mammals, cattle and pigs. Isolates were identified by serogrouping, cross agglutination absorption test (CAAT), and molecular typing. Common Leptospira serovars with their respective animal hosts were: Sokoine (cattle and rodents); Kenya (rodents and shrews); Mwogolo (rodents); Lora (rodents); Qunjian (rodent); serogroup Grippotyphosa (cattle); and an unknown serogroup from pigs. Inclusion of local serovars particularly serovar Sokoine in MAT revealed a 10-fold increase in leptospirosis prevalence in Tanzania from 1.9% to 16.9% in rodents and 0.26% to 10.75% in humans. This indicates that local serovars are useful for diagnosis of human and animal leptospirosis in Tanzania and other African countries.

  12. Rapid Screening of Epidemiologically Important Salmonella enterica subsp. enterica Serovars by Whole-Cell Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry ▿

    Science.gov (United States)

    Dieckmann, Ralf; Malorny, Burkhard

    2011-01-01

    Currently, 2,610 different Salmonella serovars have been described according to the White-Kauffmann-Le Minor scheme. They are routinely differentiated by serotyping, which is based on the antigenic variability at lipopolysaccharide moieties (O antigens), flagellar proteins (H1 and H2 antigens), and capsular polysaccharides (Vi antigens). The aim of this study was to evaluate the potential of matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) mass spectrometry for rapid screening and identification of epidemiologically important Salmonella enterica subsp. enterica serovars based on specific sets of serovar-identifying biomarker ions. By analyzing 913 Salmonella enterica subsp. enterica strains representing 89 different serovars using MALDI-TOF mass spectrometry, several potentially serovar-identifying biomarker ions were selected. Based on a combination of genus-, species-, subspecies-, and serovar-identifying biomarker ions, a decision tree classification algorithm was derived for the rapid identification of the five most frequently isolated Salmonella enterica serovars, Enteritidis, Typhimurium/4,[5],12:i:-, Virchow, Infantis, and Hadar. Additionally, sets of potentially serovar-identifying biomarker ions were detected for other epidemiologically interesting serovars, such as Choleraesuis, Heidelberg, and Gallinarum. Furthermore, by using a bioinformatic approach, sequence variations corresponding to single or multiple amino acid exchanges in several biomarker proteins were tentatively assigned. The inclusivity and exclusivity of the specific sets of serovar-identifying biomarker ions for the top 5 serovars were almost 100%. This study shows that whole-cell MALDI-TOF mass spectrometry can be a rapid method for prescreening S. enterica subsp. enterica isolates to identify epidemiologically important serovars and to reduce sample numbers that have to be subsequently analyzed using conventional serotyping by slide agglutination techniques. PMID

  13. Shoot Injury Increases the Level of Persistence of Salmonella enterica Serovar Sofia and Listeria innocua on Cos Lettuce and of Salmonella enterica Serovar Sofia on Chive.

    Science.gov (United States)

    Harapas, Dean; Premier, Robert; Tomkins, Bruce; Hepworth, Graham; Ajlouni, Said

    2015-12-01

    Minor shoot injury significantly (P cos lettuce in the greenhouse. Initial mean counts of the Salmonella on the injured and uninjured cos lettuce were on the order of 6 log CFU/g. After 3 days, the mean count decreased to 4.8 log CFU/g on the injured plants compared with the significantly (P cos lettuce and S. enterica serovar Sofia on chive. The findings reaffirm earlier results with Escherichia coli and increase the impetus to avoid shoot injury during the production of cos lettuce and chive, if bacteria of food safety concern are present.

  14. VNTR molecular typing of salmonella enterica serovar typhi isolates in Kathmandu valley

    Directory of Open Access Journals (Sweden)

    B Acharya

    2012-03-01

    Full Text Available Background: Typhoid fever continues to be a worldwide health problem, especially in developing countries. Effective epidemiological surveillance is needed to monitor the presence and spread of disease. Materials and Methods: Variable number tandem repeats (VNTR was performed for Salmonella enterica serovar typhi by multiplex-PCR in 28 Nepalese isolates of sporadic typhoid fever. Results: From all 28 total isolates, we could identify 12 VNTR profiles among the isolates, signifying multiple variants in circulation within the region. Conclusion: The VNTR-based typing assay for serovar typhi isolates can be used during an outbreak of enteric fever. The typing could eventually form the basis of an effective epidemiological surveillance system for developing rational strategies to control typhoid fever. DOI: http://dx.doi.org/10.3126/jpn.v2i3.6026 JPN 2012; 2(3: 220-223

  15. The Vi capsular polysaccharide enables Salmonella enterica serovar typhi to evade microbe-guided neutrophil chemotaxis.

    Directory of Open Access Journals (Sweden)

    Tamding Wangdi

    2014-08-01

    Full Text Available Salmonella enterica serovar Typhi (S. Typhi causes typhoid fever, a disseminated infection, while the closely related pathogen S. enterica serovar Typhimurium (S. Typhimurium is associated with a localized gastroenteritis in humans. Here we investigated whether both pathogens differ in the chemotactic response they induce in neutrophils using a single-cell experimental approach. Surprisingly, neutrophils extended chemotactic pseudopodia toward Escherichia coli and S. Typhimurium, but not toward S. Typhi. Bacterial-guided chemotaxis was dependent on the presence of complement component 5a (C5a and C5a receptor (C5aR. Deletion of S. Typhi capsule biosynthesis genes markedly enhanced the chemotactic response of neutrophils in vitro. Furthermore, deletion of capsule biosynthesis genes heightened the association of S. Typhi with neutrophils in vivo through a C5aR-dependent mechanism. Collectively, these data suggest that expression of the virulence-associated (Vi capsular polysaccharide of S. Typhi obstructs bacterial-guided neutrophil chemotaxis.

  16. Outbreak of Salmonella enterica serovar Typhimurium phage type DT41 in Danish poultry production

    DEFF Research Database (Denmark)

    Löfström, Charlotta; Hintzmann, Ann-Sofie; Sørensen, Gitte

    2015-01-01

    Salmonella enterica subspecies enterica serovar Typhimurium (S. Typhimurium) is one of the most prevalent serovars in Europe - where both poultry and poultry related products are common sources of human salmonellosis. Due to efficient control programs, the prevalence of S. Typhimurium in Danish...... poultry production is very low. Despite this, during the past decades there has been a reoccurring problem with infections with S. Typhimurium phage type DT41 in the Danish poultry production without identifying a clear source. In the end of 2013 and beginning of 2014 an increased isolation of S....... Typhimurium DT41 was noted mainly in this production, but also in other samples. To investigate this is in more detail, 47 isolates from egg layers (n = 5, 1 flock), broilers (n = 33, 13 flocks), broiler breeding flocks and hatches (n = 5; 2 flocks and 1 environmental hatchery sample), feed (n = 1), poultry...

  17. Diversity and antimicrobial susceptibility of Salmonella enterica serovars isolated from pig farms in Ibadan, Nigeria

    DEFF Research Database (Denmark)

    Fashae, Kayode; Hendriksen, Rene S.

    2014-01-01

    Kingston (n = 13; 5.7 %). The most widely distributed serovars among the farms were Salmonella Give (six farms) and Salmonella Elisaberthville (six farms). Resistance to chloramphenicol, sulfonamides, nalidixic acid, streptomycin, and tetracycline ranged from 11.6 % (n = 26) to 22.8 % (n = 51). Resistance...... of plasmid-mediated quinolone resistance (PMQR) genes in pigs in Ibadan, Nigeria. Pooled fresh pen floor fecal samples of pigs collected from 31 pig farms were cultured; the Salmonella isolates were serotyped and their antimicrobial susceptibility was determined. PMQR genes were screened by polymerase chain...... ciprofloxacin and gentamicin was low (n = 2; 0.9 %). Multiply resistant isolates included Salmonella Kentucky, the most resistant serovar. qnrB19 was found in two isolates of Salmonella Corvallis and one isolate of Salmonella Larochelle, respectively, while qnrS1 was found in two isolates of Salmonella Derby...

  18. SR450 And Superhawk XP Applications Of Bacillus thuringiensis israelensis Against Culex quinquefasciatus.

    Science.gov (United States)

    Dunford, James C; Stoops, Craig A; Estep, Alden S; Britch, Seth C; Richardson, Alec G; Walker, Todd W; Farooq, Muhammad; Hoel, David F; Platt, Raymond R; Smith, Vincent L; Wirtz, Robert A; Kerce, Jerry D

    2014-09-01

    Sprayer comparisons and larval morality assays were conducted following SR450 backpack mist blower and Superhawk XP thermal fogger applications of Vectobac® WDG Bacillus thuringiensis israelensis (Bti) against Culex quinquefasciatus. Bacillus thuringiensis israelensis was applied at maximum label rate in a 232.26-m(2) field plot located in north-central Florida with containers placed at 2 heights (ground level and 1.52 m above ground) on stakes positioned 3.04, 6.09, 9.14, 12.19, and 15.24 m from the spray line. Results indicated that there was no significant (P > 0.05) difference in 24- and 48-h larval mortality between the 2 sprayers or between the 2 heights. There was significant difference (P 70% larval mortality 3.04-9.14 m from the spray line, and control mosquito larvae.

  19. Are nematodes a missing link in the confounded ecology of the entomopathogen Bacillus thuringiensis?

    Science.gov (United States)

    Ruan, Lifang; Crickmore, Neil; Peng, Donghai; Sun, Ming

    2015-06-01

    Bacillus thuringiensis, which is well known as an entomopathogen, has been accepted by the public as a safe bioinsecticide. The natural ecology of this bacterium has never been particularly clear, with views ranging from it being an obligate pathogen to an opportunist pathogen that can otherwise exist as a soil saprophyte or a plant endophyte. This confusion has recently led to it being considered as an environmental pathogen that has evolved to occupy a diverse set of environmental niches in which it can thrive without needing a host. A significant driving force behind this classification is the fact that B. thuringiensis is found in high numbers in environments that are not occupied by the insect hosts to which it is pathogenic. It is our opinion that the ubiquitous presence of this bacterium in the environment is the result of a variety of vectoring systems, particularly those that include nematodes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Laser He-Ne effect on bacillus thuringiensis var. kurstaki strain LBT-24

    International Nuclear Information System (INIS)

    Dias, Adriana; Barreara, Lenay; Otero, Isabel; Rabelo, Yanet; Rodriguez, Dania

    1999-01-01

    Bacillus thuringiensis toxin is one of the world widely used entomopathogen. It presents an strong insecticide activity on Lepidoptera, Coleoptera and Diptera. It was studied the effect of Laser He-Ne on Bacillus thuringiensis var. kurstaki strain LBT-24. Growing curves were made and were calculated the duplication time and the specific growing speed of each one. The curves were statistically compared. It was also analysed the phage induction with and without Laser red light influence. Also, it was observed the presence of the d-endotoxin crystal with this treatment. The red Laser He-Ne enhanced the growth of this micro-organism under laboratory conditions and didn't have any effect over the other characteristics analysed

  1. Enhancement of virulence of bacillus thuringiensis and serratia marcescens by chemicals

    International Nuclear Information System (INIS)

    Khan, K. A.

    2006-01-01

    Studies were conducted on the enhancement of pathogenicity of Bacillus thuringiensis by 1% boric acid against various species of termites. The increase in virulence of Serratia marcescens by 1% potassium chloride or 1% Sodium citrate against the workers of M. championi has also been established. The increase in virulence is confirmed by the enhancement ratio, which are ranging from about 1.5 to 1.8 for Bacillus thuringiensis and 1.3 to 1.6 for Serratia marcescens. It was also noted that 1% boric acid alone was found toxic to various species of termites. However, Potassium chloride and Sodium citrate in a concentration of 1% were non-toxic to the workers of M. championi. (author)

  2. Larvicidal activity of Bacillus thuringiensis var. israelensis Cry11Aa toxin against Haemonchus contortus.

    Science.gov (United States)

    DE Lara, Ana Paula DE Souza Stori; Lorenzon, Lucas Bigolin; Vianna, Ana Muñoz; Santos, Francisco Denis Souza; Pinto, Luciano Silva; Aires Berne, Maria Elisabeth; Leite, Fábio Pereira Leivas

    2016-10-01

    Effective control of gastrointestinal parasites is necessary in sheep production. The development of anthelmintics resistance is causing the available chemically based anthelmintics to become less effective. Biological control strategies present an alternative to this problem. In the current study, we tested the larvicidal effects of Bacillus thuringiensis var. israelensis Cry11Aa toxin against Haemonchus contortus larvae. Bacterial suspensions [2 × 108 colony-forming units (CFU) g-1 of the feces] of B. thuringiensis var. israelensis and recombinant Escherichia coli expressing Cry11Aa toxin were added to naturally H. contortus egg-contaminated feces. The larvae were quantified, and significant reductions of 62 and 81% (P var. israelensis and recombinant E. coli expressing Cry11Aa toxin were then orally administered to lambs naturally infected with H. contortus. Twelve hours after administration, feces were collected and submitted to coprocultures. Significant larvae reductions (P var. israelensis is a promising new class of biological anthelmintics for treating sheep against H. contortus.

  3. Functional Analysis of Genes in the rfb Locus of Leptospira borgpetersenii Serovar Hardjo Subtype Hardjobovis

    OpenAIRE

    Bulach, Dieter M.; Kalambaheti, Thareerat; de la Peña-Moctezuma, Alejandro; Adler, Ben

    2000-01-01

    Lipopolysaccharide (LPS) is a key antigen in immunity to leptospirosis. Its biosynthesis requires enzymes for the biosynthesis and polymerization of nucleotide sugars and the transport through and attachment to the bacterial membrane. The genes encoding these functions are commonly clustered into loci; for Leptospira borgpetersenii serovar Hardjo subtype Hardjobovis, this locus, named rfb, spans 36.7 kb and contains 31 open reading frames, of which 28 have been assigned putative functions on ...

  4. Salmonella serovars and antimicrobial resistance in strains isolated from wild animals in captivity in Sinaloa, Mexico

    OpenAIRE

    Silva-Hidalgo, Gabriela; López-Valenzuela, Martin; Juárez-Barranco, Felipe; Montiel-Vázquez, Edith; Valenzuela-Sánchez, Beatriz

    2014-01-01

    The aim of the present study was to evaluate the frequency of antibiotic resistance in Salmonella spp. strains from wild animals in captivity at the Culiacan Zoo and the Mazatlan Aquarium in Sinaloa, Mexico. We identified 17 different Salmonella enterica serovars at a prevalence of 19.90% (Culiacan Zoo) and 6.25% (Mazatlan Aquarium). Antibiotic sensitivity tests revealed that, of the 83 strains studied, 100% were multidrug resistant (MDR). The drugs against which the greatest resistance was o...

  5. Molecular Characterisation of Salmonella enterica Serovar Typhi Isolated from Typhoidial Humans

    Directory of Open Access Journals (Sweden)

    Arunava Das

    2012-09-01

    Full Text Available Aims: Salmonella enterica serovar Typhi is the major causative agent for typhoidial fever around the globe among human population reported till date. Present research work was carried out for detection and molecular characterisation of Salmonella enterica serovar Typhi isolated from humans with Typhoidial fever by biochemical, phenotypical and virulence gene based polymerase chain reaction (PCR techniques. The isolated strains were also investigated for antibiotic susceptibility patterns as a control measure. Methodology and Results: A total of 16 clinical samples were collected from the same numbers of patients (7 males and 9 females from Coimbatore, Erode and Salem districts of Tamil Nadu and were processed via broth enrichment methods for isolation and identification of the causative agent S. enterica serovar Typhi. Microbiological and biochemical investigations revealed the presence of S. Typhi from 16 samples. The biotyping of the isolates showed that all the isolates belonged to biotype IV. The PCR analysis confirmed the presence of invA (Invasion gene, 244bp, tyv (Tyveloseepimerase gene, 615 bp, fliC-d (Phage-1 flagellin gene for d-antigen, 750 bp and viaB (Vi antigen gene, 439bp in all 16 clinical samples. The antibiotic susceptibility test that was carried out among the isolates against 12 antimicrobial agents, showed 100 % resistance to only ampicillin and 100 % sensitivity to carbenicillin, chloramphenicol, clindamycin, gentamycin, kanamycin and tetracycline.Conclusion, significance and impact of study: This study confirmed the association of virulent strains of S. enterica serovar Typhi from Typhoidial fever among human population and suggested that PCR based diagnostic could be very useful for the rapid detection of S. Typhi isolates. Present study emphasized the use of antibiotic like chloramphenicol or in combination with other antibiotics for the effective control of S. Typhi.

  6. Extended-spectrum cephalosporin- resistant Salmonella enterica serovar heidelberg strains, the Netherlands

    NARCIS (Netherlands)

    Liakopoulos, Apostolos; Geurts, Yvon; Dierikx, Cindy M.; Brouwer, Mike; Kant, Arie; Wit, Ben; Heymans, Raymond; Pelt, Van Wilfrid; Mevius, Dik J.

    2016-01-01

    Extended-spectrum cephalosporin-resistant Salmonella enterica serovar Heidelberg strains (JF6X01.0022/XbaI.0251, JF6X01.0326/XbaI.1966, JF6X01.0258/XbaI.1968, and JF6X01.0045/XbaI.1970) have been identified in the United States with pulsed-field gel electrophoresis. Our examination of isolates

  7. Genome-wide codon usage profiling of ocular infective Chlamydia trachomatis serovars and drug target identification.

    Science.gov (United States)

    Sadhasivam, Anupriya; Vetrivel, Umashankar

    2017-07-04

    Chlamydia trachomatis (C.t) is a Gram-negative obligate intracellular bacteria and is a major causative of infectious blindness and sexually transmitted diseases. Among the varied serovars of this organism, A, B and C are reported as prominent ocular pathogens. Genomic studies of these strains shall aid in deciphering potential drug targets and genomic influence on pathogenesis. Hence, in this study we performed deep statistical profiling of codon usage in these serovars. The overall base composition analysis reveals that these serovars are over biased to AU than GC. Similarly, relative synonymous codon usage also showed preference towards A/U ending codons. Parity Rule 2 analysis inferred unequal distribution of AT and GC, indicative of other unknown factors acting along with mutational pressure to influence codon usage bias (CUB). Moreover, absolute quantification of CUB also revealed lower bias across these serovars. The effect of natural selection on CUB was also confirmed by neutrality plot, reinforcing natural selection under mutational pressure turned to be a pivotal role in shaping the CUB in the strains studied. Correspondence analysis (COA) clarified that, C.t C/TW-3 to show a unique trend in codon usage variation. Host influence analysis on shaping the codon usage pattern also inferred some speculative relativity. In a nutshell, our finding suggests that mutational pressure is the dominating factor in shaping CUB in the strains studied, followed by natural selection. We also propose potential drug targets based on cumulative analysis of strand bias, CUB and human non-homologue screening.

  8. Histopathology and the lethal effect of Cry proteins and strains of Bacillus thuringiensis Berliner in Spodoptera frugiperda J.E. Smith Caterpillars (Lepidoptera, Noctuidae

    Directory of Open Access Journals (Sweden)

    N. Knaak

    Full Text Available Among the phytophagous insects which attack crops, the fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797 (Lepidoptera, Noctuidae is particularly harmful in the initial growth phase of rice plants. As a potential means of controlling this pest, and considering that the entomopathogen Bacillus thuringiensis Berliner demonstrates toxicity due to synthesis of the Cry protein, the present study was undertaken to evaluate this toxic effect of B. thuringiensis thuringiensis 407 (pH 408 and B. thuringiensis kurstaki HD-73 on S. frugiperda. The following method was used. Both bacterial strains were evaluated in vitro in 1st instar S. frugiperda caterpillars, by means of histopathological assays. The Cry1Ab and Cry1Ac proteins, codified by the respective strains of B. thuringiensis, were evaluated in vivo by bioassays of 1st instar S. frugiperda caterpillars in order to determine the Mean Lethal Concentration (LC50. The results of the histopathological analysis of the midget of S. frugiperda caterpillars demonstrate that treatment with the B. thuringiensis thuringiensis strain was more efficient, because the degradations of the microvilosities started 9 hours after treatment application (HAT, while in the B. thuringiensis kurstaki the same effect was noticed only after 12 HAT. Toxicity data of the Cry1Ab and Cry1Ac proteins presented for the target-species LC50 levels of 9.29 and 1.79 μg.cm-2 respectively. The strains and proteins synthesised by B. thuringiensis thuringiensis and B. thuringiensis kurstaki are effective in controlling S. frugiperda, and may be used to produce new biopesticides or the genes may be utilised in the genetic transformation of Oryza sativa L.

  9. [Septicaemia of chironomid larvae (Diptera: Chironomidae) promoted by Bacillus cereus and B. thuringiensis].

    Science.gov (United States)

    Khodyrev, V P

    2012-01-01

    Natural factors regulating the population of chironomids were studied. The bacteria Bacillus cereus were isolated from chironomids sampled from Kuyalnitskii Firth after epizooty of Chironomus sp., and bacteria Bacillus thuringiensis spp. israelensis (Bti) were isolated from dead larva of Chironomus plumosus sampled in the Sea of Azov (3-m depth). Bti were characterized by high insecticide activity on midges Anopheles messeae Fall., Aedes cireneus Mg., and Culex pipiens pipiens f. pipiens L.

  10. Efektifitas Bacillus Thuringiensis Yang Diisolasi Dari Sampel Tanah Di YOGYAKARTA Terhadap Larva Culex Quinquefasciatus Invitro

    OpenAIRE

    Suryani, Lilis

    2008-01-01

    Filariasis disease is a public health problem, especially in rural areas. One kinds of mosquitoes that transmited it is Culex quinquefasciatus. Since 1972 chemical insecticides has been usedfor vector control in Indonesia. However, in 1987 it was reported that there are many areas has been resistant against chemical insecticides. Bacillus thuringiensis is a gram positif bacteria, rod, aerobic and spore shape. There are many strain of this bacteria produces a toxic protein to insect. This rese...

  11. Genetical and radiobiological characteristics of phage Tg13 of Bacillus thuringiensis

    International Nuclear Information System (INIS)

    Takubova, R.M.; Azizbekyan, R.R.

    1979-01-01

    The radiation-genetical aspects of interrelations between phages and cells of the spore-forming bacteria Bacillus thurin-giensis were studied. The phage Tg13 liberates C-mutants, forming transparent negative colonies, both spontaneously and under the effect of UV irradiation. UV-radiation increases reliably the level of C-mutants in the population. The phenotype of the observed mutants is, evidently, caused by the specific features of interaction in the system: preudolysogenic culture -phage Tg13

  12. Activity of Bacillus thuringiensis D(delta)-endotoxins against codling moth (Cydia pomonella L.) larvae

    NARCIS (Netherlands)

    Boncheva, R.; Dukiandjiev, S.; Minkov, I.; Maagd, de R.A.; Naimov, S.

    2006-01-01

    Solubilized protoxins of nine Cry1 and one hybrid Cry1 ¿-endotoxin from Bacillus thuringiensis were tested for their activity against larvae of the codling moth (Cydia pomonella L). Cry1Da was the most toxic, followed by Cry1Ab, Cry1Ba, and Cry1Ac, while Cry1Aa, Cry1Fa, Cry1Ia, and SN19 were still

  13. Germination and persistence of Bacillus anthracis and Bacillus thuringiensis in soil microcosms.

    Science.gov (United States)

    Bishop, A H

    2014-11-01

    Decontaminating large, outdoor spaces of Bacillus anthracis spores presents significant problems, particularly in soil. Proof was sought that the addition of germinant chemicals could cause spores of B. anthracis and Bacillus thuringiensis, a commonly used simulant of the threat agent, to convert to the less resistant vegetative form in a microcosm. Nonsterile plant/soil microcosms were inoculated with spores of B. thuringiensis and two nonpathogenic strains of B. anthracis. A combination of L-alanine (100 mmol l(-1)) and inosine (10 mmol l(-1)) resulted in a 6 log decrease in spore numbers in both strains of B. anthracis over 2 weeks at 22°C; a 3 log decrease in B. anthracis Sterne spore numbers was observed after incubation for 2 weeks at 10°C. Negligible germination nor a decrease in viable count occurred in either strain when the concentration of L-alanine was decreased to 5 mmol l(-1). Germinated spores of B. thuringiensis were able to persist in vegetative form in the microcosms, whereas those of B. anthracis rapidly disappeared. The pleiotropic regulator PlcR, which B. anthracis lacks, does not contribute to the persistence of B. thuringiensis in vegetative form in soil. The principle of adding germinants to soil to trigger the conversion of spores to vegetative form has been demonstrated. Bacillus anthracis failed to persist in vegetative form or resporulate in the microcosms after it had been induced to germinate. The large scale, outdoor decontamination of B. anthracis spores may be facilitated by the application of simple, defined combinations of germinants. © 2014 Crown Copyright. Journal of Applied Microbiology © 2014 Society for Applied Microbiology This article is Published with the permission of the Controller of HMSO and Queen's Printer for Scotland.

  14. The potential of the novel mosquitocidal Bacillus thuringiensis strain LLP29 for use in practice

    Czech Academy of Sciences Publication Activity Database

    Zhang, L.; Wu, S.; Peng, Y.; Li, M.; Sun, L.; Huang, E.; Guan, X.; Gelbič, Ivan

    2011-01-01

    Roč. 36, č. 2 (2011), s. 458-460 ISSN 1081-1710 R&D Projects: GA MŠk 2B08003 Grant - others:National Natural Science Foundation of China (CN) 31071745; Science Foundation of the Ministry of Education of China (CN) 20093515110010; Science Foundation of the Ministry of Education of China (CN) 20093515120010 Institutional research plan: CEZ:AV0Z50070508 Keywords : Bacillus thuringiensis Subject RIV: ED - Physiology Impact factor: 0.885, year: 2011

  15. Biological Activity of Bacillus thuringiensis (Bacillales: Bacillaceae) in Anastrepha fraterculus (Diptera: Tephritidae).

    Science.gov (United States)

    Martins, Liliane Nachtigall; Lara, Ana Paula de Souza Stori de; Ferreira, Márcio Soares; Nunes, Adrise Medeiros; Bernardi, Daniel; Leite, Fábio Pereira Leivas; Garcia, Flávio Roberto Mello

    2018-01-18

    Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) is considered to be one of the major pest insects in fruit orchards worldwide. Bacillus thuringiensis Berliner (Bacillales: Bacillaceae) strains are widely used as biological control agents and show high biological activity against different insect species. The objective of this study was to evaluate the biological activity of different strains of B. thuringiensis against A. fraterculus larvae and adults. Bioassays were performed using suspensions of bacterial spores/crystals of B. thuringiensis var. israelensis (Bti), kurstaki (Btk), and oswaldocruzi (Bto) strains at three concentrations [2 × 107, 2 × 108, and 2 × 109 colony-forming units per ml (CFU ml-1)]. At a concentration of 2 × 109 CFU ml-1, a significant larval effect (mortality 60%) was observed when compared with the control treatment. Larvae that ingested spore/crystal suspensions of Bti, Btk, or Bto bacterial strains exhibited significant larval and pupal deformations, leading to a significant decrease (~50%) in the completion of the insects' biological cycle (egg to adult). The B. thuringiensis strains (Bti, Btk, or Bto) at a concentration of 2 × 109 CFU ml-1 in combination with one food attractant (BioAnastrepha 3% or CeraTrap 1.5%) in formulations of toxic baits provided high mortality (mortality > 85%) of A. fraterculus adults 7 d after treatment. However, the Btk strain in combination with CeraTrap 1.5% caused mortality of 40%. On the basis of these results, the native bacterial strains Bti, Btk, and Bto were considered to be promising candidates as biological control agents against A. fraterculus. © The Author(s) 2018. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Nano-Mechanical Properties of Heat Inactivated Bacillus anthracis and Bacillus thuringiensis Spores

    Science.gov (United States)

    2008-03-01

    spores were grown in plastic petri dishes on Criterion Dehydrated Culture Media , which contained per liter of formula 15 grams agar , 5 grams gelatin...became reality in 2001 when terrorists sent spores in a powdered form in letters to two senators and several news media offices, killing five people...is the causative agent of the disease anthrax. B. thuringiensis is often used in pesticides and bioengineering pest resistant crops because of its

  17. La bioetica sotto accusa. Osservazioni e considerazioni critiche

    Directory of Open Access Journals (Sweden)

    LO SAPIO, LUCA

    2017-06-01

    Full Text Available Bioethics on trial. Remarks and critical Observations After the definitive consecration of Bioethics, both at the academic and at the public level some scholars, from the early years of the new century, have begun to move criticism into various aspects of the discipline. In the present paper, after a brief medicineintroduction of historical character (§ 2, I will present some of these criticisms (§ 3 by highlighting strengths and weaknesses (§ 4. In the final paragraph (§5, I maintain that bioethics, despite some critical elements, can still be an important discipline both to understand the transformations of our society induced by biomedical developments and to provide homo technologicus with useful tools to guide his own moral conduct.

  18. Using Shakespeare's Sotto Voce to Determine True Identity From Text

    Directory of Open Access Journals (Sweden)

    David Kernot

    2018-03-01

    Full Text Available Little is known of the private life of William Shakespeare, but he is famous for his collection of plays and poems, even though many of the works attributed to him were published anonymously. Determining the identity of Shakespeare has fascinated scholars for 400 years, and four significant figures in English literary history have been suggested as likely alternatives to Shakespeare for some disputed works: Bacon, de Vere, Stanley, and Marlowe. A myriad of computational and statistical tools and techniques have been used to determine the true authorship of his works. Many of these techniques rely on basic statistical correlations, word counts, collocated word groups, or keyword density, but no one method has been decided on. We suggest that an alternative technique that uses word semantics to draw on personality can provide an accurate profile of a person. To test this claim, we analyse the works of Shakespeare, Christopher Marlowe, and Elizabeth Cary. We use Word Accumulation Curves, Hierarchical Clustering overlays, Principal Component Analysis, and Linear Discriminant Analysis techniques in combination with RPAS, a multi-faceted text analysis approach that draws on a writer's personality, or self to identify subtle characteristics within a person's writing style. Here we find that RPAS can separate the known authored works of Shakespeare from Marlowe and Cary. Further, it separates their contested works, works suspected of being written by others. While few authorship identification techniques identify self from the way a person writes, we demonstrate that these stylistic characteristics are as applicable 400 years ago as they are today and have the potential to be used within cyberspace for law enforcement purposes.

  19. Temperature and oxygen dependent metabolite utilization by Salmonella enterica serovars Derby and Mbandaka.

    Directory of Open Access Journals (Sweden)

    Matthew R Hayward

    Full Text Available Salmonella enterica is a zoonotic pathogen of clinical and veterinary significance, with over 2500 serovars. In previous work we compared two serovars displaying host associations inferred from isolation statistics. Here, to validate genome sequence data and to expand on the role of environmental metabolite constitution in host range determination we use a phenotypic microarray approach to assess the ability of these serovars to metabolise ~500 substrates at 25°C with oxygen (aerobic conditions to represent the ex vivo environment and at 37°C with and without oxygen (aerobic/anaerobic conditions to represent the in vivo environment. A total of 26 substrates elicited a significant difference in the rate of metabolism of which only one, D-galactonic acid-g-lactone, could be explained by the presence (S. Mbandaka or the absence (S. Derby of metabolic genes. We find that S. Mbandaka respires more efficiently at ambient temperatures and under aerobic conditions on 18 substrates including: glucosominic acid, saccharic acid, trehalose, fumaric acid, maltotriose, N-acetyl-D-glucosamine, N-acetyl-beta-D-mannosamine, fucose, L-serine and dihydroxy-acetone; whereas S. Derby is more metabolically competent anaerobically at 37°C for dipeptides, glutamine-glutamine, alanine-lysine, asparagine-glutamine and nitrogen sources glycine and nitrite. We conclude that the specific phenotype cannot be reliably predicted from the presence of metabolic genes directly relating to the metabolic pathways under study.

  20. The sensitivity of real-time PCR amplification targeting invasive Salmonella serovars in biological specimens

    Directory of Open Access Journals (Sweden)

    Chau Tran

    2010-05-01

    Full Text Available Abstract Background PCR amplification for the detection of pathogens in biological material is generally considered a rapid and informative diagnostic technique. Invasive Salmonella serovars, which cause enteric fever, can be commonly cultured from the blood of infected patients. Yet, the isolation of invasive Salmonella serovars from blood is protracted and potentially insensitive. Methods We developed and optimised a novel multiplex three colour real-time PCR assay to detect specific target sequences in the genomes of Salmonella serovars Typhi and Paratyphi A. We performed the assay on DNA extracted from blood and bone marrow samples from culture positive and negative enteric fever patients. Results The assay was validated and demonstrated a high level of specificity and reproducibility under experimental conditions. All bone marrow samples tested positive for Salmonella, however, the sensitivity on blood samples was limited. The assay demonstrated an overall specificity of 100% (75/75 and sensitivity of 53.9% (69/128 on all biological samples. We then tested the PCR detection limit by performing bacterial counts after inoculation into blood culture bottles. Conclusions Our findings corroborate previous clinical findings, whereby the bacterial load of S. Typhi in peripheral blood is low, often below detection by culture and, consequently, below detection by PCR. Whilst the assay may be utilised for environmental sampling or on differing biological samples, our data suggest that PCR performed directly on blood samples may be an unsuitable methodology and a potentially unachievable target for the routine diagnosis of enteric fever.

  1. Gonorrhoea: auxotypes, serovars, and clinical manifestations among female sex workers from Kinshasa, Zaïre.

    Science.gov (United States)

    Mukenge-Tshibaka, L; Alary, M; Van Dyck, E; Laga, M; Nzila, N

    1997-12-01

    The main question in this paper was to look at the distribution of auxotypes and serovars of Neisseria gonorrhoeae and check whether they correlate with clinical symptoms/signs among female sex workers (FSW) from Kinshasa, Zaïre. The subject were 1233 FSW enrolled in a cross sectional study on STDs and HIV infection in 1988; 771 of them were followed prospectively for a median duration of 23 months. At each visit, clinical symptoms and signs of cervicitis were recorded and the subjects were screened for gonococcal and chlamydial infection. The pre-dominant auxotypes were prototrophic (35.2%), proline requiring (29.6%), and proline requiring phenylalanine inhibition (19%). Serovars 1A-6 (42.5%) and 1B-1 (16.7%) were the commonest. Infection with auxotype prototrophic and phenylalanine inhibition (Proto/Phenali) was significantly associated with both mucopurulent cervicitis and pelvic inflammatory disease; (OR = 8.9; p = 0.002 and OR =19 x9; p = 0.002; respectively). Despite the few associations found in this study, there was not clear pattern linking clinical manifestations to auxotype/serovar profiles.

  2. Supplemental invasion of Salmonella from the perspective of Salmonella enterica serovars Kentucky and Typhimurium.

    Science.gov (United States)

    Howe, Kevin; Salehi, Sanaz; Hartford Bailey, R; Brooks, John P; Wills, Robert; Lawrence, Mark L; Karsi, Attila

    2017-04-05

    Critical to the development of Salmonellosis in humans is the interaction of the bacterium with the epithelial lining of the gastrointestinal tract. Traditional scientific reasoning held type III secretion system (T3SS) as the virulence factor responsible for bacterial invasion. In this study, field-isolated Salmonella enterica serovar Kentucky and a known human pathogen Salmonella enterica serovar Typhimurium were mutated and evaluated for the invasion of human colorectal adenocarcinoma epithelial cells. S. enterica serovar Kentucky was shown to actively invade a eukaryotic monolayer, though at a rate that was significantly lower than Typhimurium. Additionally, strains mutated for T3SS formation were less invasive than the wild-type strains, but the decrease in invasion was not significant in Kentucky. Strains mutated for T3SS formation were able to initiate invasion of the eukaryotic monolayer to varying degrees based on strain, In the case of Kentucky, the mutated strain initiated invasion at a level that was not significantly different from the wild-type strain. A different result was observed for Typhimurium as the mutation significantly lowered the rate of invasion in comparison to the wild-type strain.

  3. Characterization of Leptospira santarosai Serogroup Grippotyphosa Serovar Bananal Isolated from Capybara ( Hydrochaeris hydrochaeris ) in Brazil.

    Science.gov (United States)

    Moreno, Luisa Z; Miraglia, Fabiana; Marvulo, Maria F V; Silva, Jean C R; Paula, Catia D; Costa, Barbara L P; Morais, Zenaide M; Ferreira, Fernando; Neto, José S Ferreira; Dellagostin, Odir A; Hartskeerl, Rudy A; Vasconcellos, Silvio A; Moreno, Andrea M

    2016-07-01

    Leptospirosis is a widespread zoonosis caused by bacteria of the genus Leptospira. Rodents appear to be the most important reservoirs of infection. They contaminate the environment and food and can transmit the pathogen when they are consumed by carnivores. Capybara ( Hydrochaeris hydrochaeris ) are efficient reservoirs of Leptospira, and because they are in close contact with farm animals and are found in semiurban areas, they represent a risk to public health. We isolated five Leptospira strains from capybara kidneys in Sao Paulo State, Brazil, in 2001 and typed them using serologic and molecular techniques. These strains include the Leptospira santarosai serogroup Grippotyphosa serovar Bananal. Pulsed field gel electrophoresis resulted in a unique pattern distinct from the reference strains, and the isolates clustered with greater than 85% similarity. The isolates also presented higher growth rates than other Leptospira serovars, with high minimal inhibitory concentration values for most of the tested antibiotics, with the exception of penicillin and ampicillin. This isolation and characterization of the L. santarosai serogroup Grippotyphosa serovar Bananal from capybara, highlights the importance of wild and sinantropic rodents as carriers of pathogenic leptospires.

  4. Detection of OmpA gene by PCR for specific detection of Salmonella serovars

    Directory of Open Access Journals (Sweden)

    Joy. L. Kataria

    2013-10-01

    Full Text Available Aim: The study was carried out to determine the sensitivity and specificity of OmpA gene in Salmonella serovarsthrough PCR.Materials and Methods: Aset of primers were designed targeting the OmpAgene specific for the Salmonella and polymerasechain reaction was standardized using Salomonella Typhimurium as a positive control and as a negative control 4 nonsalmonella cultures such as Campylobacter coli, Arcobacter butzleri, Brucella abortus and E. coli. Sensitivity of the test wasdetermined by serial dilution of genomic DNAof standard S. Typhimurium. The PCR standardized was used for screening 68strains of different serovars of Salmonella.Results: The PCR developed targeting OmpA specific for Salmonella was highly specific in detection of the salmonellaserovar alone and sensitivity was upto 68.8 fg. Atotal of 68 virulent/ natural strains of different serovars of salmonella takenup for the study were positive by OmpAbased PCR.Conclusions: This study reports that, OmpAgene which is conserved among Salmonella serovars can be used for the detectionof Salmonella in food or clinical samples in further studies, with high sensitivity and specificity.

  5. Synergistic effect of certain insecticides combined with Bacillus thuringiensis on mosquito larvae

    Directory of Open Access Journals (Sweden)

    C.P. Narkhede

    2017-04-01

    Full Text Available For effective vector control it is essential to formulate new preparations having multiple action against the vector pest. Developing combined formulation of biopesticide and chemical pesticide is one of the novel concept to fight against the vectors with new weapons; however, compatibility of biopesticide i.e. Bacillus thuringiensis (Bt and chemical pesticide is a real hurdle. In this investigation, local isolate Bacillus thuringiensis SV2 (BtSV2 was tested for its compatibility with various available mosquito larvicides. Temephos was most compatible with BtSV2 than with other tested pesticides. These two compatible agents were tested for larvicidal potential. Our study revealed that the synergistic effect of both agents reduces LC50 value by 30.68 and 22.36% against the Ae. aegypti and An. stephensi, respectively. The larvicidal potential increased when compared to individual pesticides. It was also observed a biochemical change in larvae after the TBT (Temephos + Bacillus thuringiensis combination treatment; it involves decreased level of alpha esterase, acetylcholine esterase and protein while level of beta esterase and acid phosphatase was unchanged and alkaline phosphatase activity was increased. Increased potential of combined formulation may be due to altered physiological condition.

  6. Experimental design and Bayesian networks for enhancement of delta-endotoxin production by Bacillus thuringiensis.

    Science.gov (United States)

    Ennouri, Karim; Ayed, Rayda Ben; Hassen, Hanen Ben; Mazzarello, Maura; Ottaviani, Ennio

    2015-12-01

    Bacillus thuringiensis (Bt) is a Gram-positive bacterium. The entomopathogenic activity of Bt is related to the existence of the crystal consisting of protoxins, also called delta-endotoxins. In order to optimize and explain the production of delta-endotoxins of Bacillus thuringiensis kurstaki, we studied seven medium components: soybean meal, starch, KH₂PO₄, K₂HPO₄, FeSO₄, MnSO₄, and MgSO₄and their relationships with the concentration of delta-endotoxins using an experimental design (Plackett-Burman design) and Bayesian networks modelling. The effects of the ingredients of the culture medium on delta-endotoxins production were estimated. The developed model showed that different medium components are important for the Bacillus thuringiensis fermentation. The most important factors influenced the production of delta-endotoxins are FeSO₄, K2HPO₄, starch and soybean meal. Indeed, it was found that soybean meal, K₂HPO₄, KH₂PO₄and starch also showed positive effect on the delta-endotoxins production. However, FeSO4 and MnSO4 expressed opposite effect. The developed model, based on Bayesian techniques, can automatically learn emerging models in data to serve in the prediction of delta-endotoxins concentrations. The constructed model in the present study implies that experimental design (Plackett-Burman design) joined with Bayesian networks method could be used for identification of effect variables on delta-endotoxins variation.

  7. 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.

  8. Activity of Bacillus thuringiensis isolates against immature horn fly and stable fly (Diptera: Muscidae).

    Science.gov (United States)

    Lysyk, T J; Kalischuk-Tymensen, L D; Rochon, K; Selinger, L B

    2010-06-01

    We screened 85 isolates of Bacillus thuringiensis (Berliner), making up 57 different subspecies, and two isolates of Bacillus sphaericus (Meyer and Neide) for activity against immature horn flies, Haematobia irritans (L.), and stable flies, Stomoxys calcitrans (L.). The majority of B. thuringiensis and the B. sphaericus isolates had little or no activity against horn fly and stable fly. Approximately 87% of the isolates caused fly larvae and 64% caused stable fly, 95% of the isolates caused fly and stable fly immatures. These isolates were B. t. tolworthi 4L3, B. t. darmstadiensis 4M1, B. t. thompsoni 401, B. t. thuringiensis HD2, and B. t. kurstaki HD945. The LD50 values ranged from 2.2 to 7.9 x 10(6) spores per g manure for horn fly and from 6.3 to 35 x 10(6) spores per g media for stable fly. These were consistently more toxic compared with the B. t. israelensis isolates examined. All had DNA that hybridized with cry1Aa, cry1Ab, and cry1Ac toxin probes, three hybridized with a cry1B probe, and two hybridized with a cry2A probe. These may have potential for use in integrated management of pest flies.

  9. Two new Brazilian isolates of Bacillus thuringiensis toxic to Anticarsia gemmatalis (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    LM. Fiuza

    Full Text Available Bacillus thuringiensis is a bacterium used for biopesticides production and pest-resistant plants due to the synthesis of protein crystals by cry genes, which are effective in controlling several insect orders such as Lepidoptera. This work aimed at the evaluation and characterisation of two new B. thuringiensis isolates active against A. gemmatalis (Hübner 1818 larvae, which is the soybean major pest. The results showed that Bt117-4 isolate amplified fragments corresponding to cry2 and cry9 genes, and synthesised protein fragments equivalent to 130, 90 and 45 kDa. The Bt3146-4 isolate amplified DNA fragments corresponding to cry9 gene and synthesised protein fragments of 70, 58 and 38 kDa. Transmission electron microscopy revealed the presence of protein crystals in both isolates. CL50 with Cry purified proteins from Bt117-4 and Bt3146-4, corresponded to 0.195 and 0.191 µg larvae-1, respectively. The two B. thuringiensis isolates selected in this study were effective to control velvetbean caterpillar at laboratory conditions. Field tests should be carried on to develop new biopesticides formulation as well for cry genes resource for Anticarsia gemmatalis resistant transgenic plants.

  10. Phosphorus Availability in Wheat, in Volcanic Soils Inoculated with Phosphate-Solubilizing Bacillus thuringiensis

    Directory of Open Access Journals (Sweden)

    Jorge Delfim

    2018-01-01

    Full Text Available The use of phosphate solubilizing bacteria (PSB is an ecological strategy that allows for increasing the availability of phosphorus (P in soil. The objective of this study was to evaluate P availability in wheat, in soils derived from volcanic ash (Andisol and Ultisol, and inoculated with phosphate-solubilizing Bacillus thuringiensis, the experiment was conducted in pots under greenhouse conditions using a completely randomized design. Wheat plants were inoculated and re-inoculated at 20 and 46 days after sowing (DAS, respectively, with B. thuringiensis; and, soil and plant sampling was performed after 46, 66, and 87 days based on the Zadoks growth scale (Z. The inoculation resulted in an 11% increase in P of the rhizosphere at Z46 (Ultisol, P also increased 34% and 67% in aerial tissues at Z46 (Andisol and Ultisol, respectively, while an increase of 75% was observed in root tissues at Z87 (Ultisol. Similarly, the inoculation resulted in increases in acid phosphatase activity (Andisol, soil microbial biomass (Andisol and Ultisol, and root biomass in plants (Ultisol, without achieving increase of the aerial biomass of the plants. The phosphate solubilizing B. thuringiensis strain showed some positive, but also negative effects in soils and plants, depending on the soil.

  11. Avaliação da eficiência de formulações de Bacillus thuringiensis para o controle de traça-das-crucíferas em repolho no Distrito Federal Efficiency of Bacillus thuringiensis formulations in controlling Diamondback Moth in cabbage in the Federal District

    Directory of Open Access Journals (Sweden)

    Marina Castelo Branco

    1999-11-01

    Full Text Available A traça-das-crucíferas (Plutella xylostella é a praga mais importante do repolho no Distrito Federal. Seu controle é feito basicamente com inseticidas. Novos produtos são constantemente avaliados para o controle da praga e neste trabalho duas novas formulações de Bacillus thuringiensis [Bacillus thuringiensis var. aizawai (350 e 500 g/hae B. thuringiensis var. kurstaki x B. thuringiensis var. aizawai (350 e 500 ml/ha] foram avaliadas no período de maio a outubro de 1995. Os tratamentos B. thuringiensis var. kurstaki (500 ml/ha, deltametrina (240 ml/ha e uma testemunha sem pulverização foram também incluídos no experimento. O delineamento foi blocos ao acaso, com sete tratamentos e quatro repetições. Os resultados mostraram que B. thuringiensis var. aizawai nas duas dosagens avaliadas e B. thuringiensis var. kurstaki x B. thuringiensis var. aizawai (500 ml/ha foram os produtos mais eficientes. Ao final do experimento larvas e pupas de traça-das-crucíferas foram coletadas no campo e a primeira geração foi submetida a um teste de laboratório onde discos de folhas de repolho foram tratados com as dosagens dos inseticidas a base de B. thuringiensis utilizadas no campo. Larvas de segundo estádio foram colocadas sobre os discos tratados e a mortalidade de larvas avaliada após 72 h. Todos os tratamentos causaram mais de 97% de mortalidade de larvas. O resultado do teste de laboratório sugere que a menor eficiência de B. thuringiensis var. kurstaki x B. thuringiensis var. aizawai (350 ml/ha e B. thuringiensis var. kurstaki (500 ml/ha no teste de campo quando comparada aos demais Bacillus, pode ser devido à mais rápida degradação destes produtos no ambiente.The Diamondback Moth (Plutella xylostella is the most important cabbage pest in the Federal District. New insecticides are frequently tested for its control and in this study two new Bacillus thuringiensis formulations [B. thuringiensis var. aizawai (350 and 500 g/ha and B

  12. Assessment of exposure to Leptospira serovars in veterinary staff and dog owners in contact with infected dogs.

    Science.gov (United States)

    Barmettler, Reto; Schweighauser, Ariane; Bigler, Susanne; Grooters, Amy M; Francey, Thierry

    2011-01-15

    To assess patterns of seroreactivity to Leptospira serovars in veterinary professional staff and dog owners exposed to dogs with acute leptospirosis and to contrast these patterns in people with those observed in dogs. Cross-sectional study. Human subjects consisted of 91 people (50 veterinarians, 19 technical staff, 9 administrative personnel, and 13 dog owners) exposed to dogs with leptospirosis. Canine subjects consisted of 52 dogs with naturally occurring leptospirosis admitted to the University of Bern Vetsuisse Faculty Small Animal Clinic in 2007 and 2008. People were tested for seroreactivity to regionally prevalent Leptospira serovars by use of a complement fixation test. A questionnaire designed to identify risk factors associated with seropositivity was used to collect demographic information from each study participant. Dogs were tested for seroreactivity to Leptospira serovars by use of a microscopic agglutination test. On the basis of microscopic agglutination test results, infected dogs were seropositive for antibodies against Leptospira serovars as follows (in descending order): Bratislava (43/52 [83%]), Australis (43/52 [83%]), Grippotyphosa (18/52 [35%]), Pomona (12/52 [23%]), Autumnalis (6/52 [12%]), Icterohemorrhagiae (4/52 [8%]), Tarassovi (2/52 [4%]), and Canicola (1/52 [2%]). All 91 people were seronegative for antibodies against Leptospira serovars. Therefore, statistical evaluation of risk factors and comparison of patterns of seroreactivity to Leptospira serovars between human and canine subjects were limited to theoretical risks. Seroreactivity to Leptospira serovars among veterinary staff adhering to standard hygiene protocols and pet owners exposed to dogs with acute leptospirosis was uncommon.

  13. Molecular Characterization of Motile Serovars of Salmonella enterica from Breeder and Commercial Broiler Poultry Farms in Bangladesh

    Science.gov (United States)

    Barua, Himel; Biswas, Paritosh K.; Olsen, Katharina E. P.; Shil, Subrata K.; Christensen, Jens P.

    2013-01-01

    Contaminated poultry and poultry products are a major source of motile Salmonellae for human salmonellosis worldwide. Local circulation of any motile Salmonella serovar in poultry has a wider public health impact beyond its source of origin for being dispersed elsewhere through poultry trades or human travels. To investigate the status of motile Salmonella serovars in breeder farms in Bangladesh, multiple flocks of two breeder farms were observed for a period of six months. In addition, a cross-sectional survey was carried out to determine the prevalence and serovar distribution of motile Salmonella by randomly selecting 100 commercial broiler poultry farms. Five pooled faecal samples representing an entire housed flock of breeders or broilers were screened for presence of motile Salmonella following conventional bacteriological procedures. The Salmonella isolates obtained were subsequently serotyped, and characterized by plasmid profiling and pulsed-field gel electrophoresis (PFGE). The results revealed that both the breeder farms were positive with three Salmonella serovars: S. Virchow, S. Paratyphi B var Java (S. Java) and S. Enteritidis. Eleven of the 100 broiler farms investigated were positive for motile Salmonella, giving a farm-level prevalence of 11% (95% confidence interval 5–17%). S. Virchow and S. Kentucky were the two predominant serovars isolated from the broiler farms. The PFGE genotyping demonstrated that the isolates belonging to the same serovars were closely related due to variation in only 1–4 bands. All the S. Virchow and S. Java isolates, irrespective of breeder or broiler farm origin, were plasmid-free, except for one S. Virchow isolate from a broiler farm that harboured a 9.7 kb-sized plasmid. The S. Kentucky isolates belonged to three plasmid profiles having plasmids of four different sizes, ranging from 2.7 to 109 kb. This is the first report of any motile Salmonella serovars from breeder and commercial broiler poultry farms in

  14. Molecular characterization of motile serovars of Salmonella enterica from breeder and commercial broiler poultry farms in Bangladesh.

    Directory of Open Access Journals (Sweden)

    Himel Barua

    Full Text Available Contaminated poultry and poultry products are a major source of motile Salmonellae for human salmonellosis worldwide. Local circulation of any motile Salmonella serovar in poultry has a wider public health impact beyond its source of origin for being dispersed elsewhere through poultry trades or human travels. To investigate the status of motile Salmonella serovars in breeder farms in Bangladesh, multiple flocks of two breeder farms were observed for a period of six months. In addition, a cross-sectional survey was carried out to determine the prevalence and serovar distribution of motile Salmonella by randomly selecting 100 commercial broiler poultry farms. Five pooled faecal samples representing an entire housed flock of breeders or broilers were screened for presence of motile Salmonella following conventional bacteriological procedures. The Salmonella isolates obtained were subsequently serotyped, and characterized by plasmid profiling and pulsed-field gel electrophoresis (PFGE. The results revealed that both the breeder farms were positive with three Salmonella serovars: S. Virchow, S. Paratyphi B var Java (S. Java and S. Enteritidis. Eleven of the 100 broiler farms investigated were positive for motile Salmonella, giving a farm-level prevalence of 11% (95% confidence interval 5-17%. S. Virchow and S. Kentucky were the two predominant serovars isolated from the broiler farms. The PFGE genotyping demonstrated that the isolates belonging to the same serovars were closely related due to variation in only 1-4 bands. All the S. Virchow and S. Java isolates, irrespective of breeder or broiler farm origin, were plasmid-free, except for one S. Virchow isolate from a broiler farm that harboured a 9.7 kb-sized plasmid. The S. Kentucky isolates belonged to three plasmid profiles having plasmids of four different sizes, ranging from 2.7 to 109 kb. This is the first report of any motile Salmonella serovars from breeder and commercial broiler poultry

  15. Molecular characterization of motile serovars of Salmonella enterica from breeder and commercial broiler poultry farms in Bangladesh.

    Science.gov (United States)

    Barua, Himel; Biswas, Paritosh K; Olsen, Katharina E P; Shil, Subrata K; Christensen, Jens P

    2013-01-01

    Contaminated poultry and poultry products are a major source of motile Salmonellae for human salmonellosis worldwide. Local circulation of any motile Salmonella serovar in poultry has a wider public health impact beyond its source of origin for being dispersed elsewhere through poultry trades or human travels. To investigate the status of motile Salmonella serovars in breeder farms in Bangladesh, multiple flocks of two breeder farms were observed for a period of six months. In addition, a cross-sectional survey was carried out to determine the prevalence and serovar distribution of motile Salmonella by randomly selecting 100 commercial broiler poultry farms. Five pooled faecal samples representing an entire housed flock of breeders or broilers were screened for presence of motile Salmonella following conventional bacteriological procedures. The Salmonella isolates obtained were subsequently serotyped, and characterized by plasmid profiling and pulsed-field gel electrophoresis (PFGE). The results revealed that both the breeder farms were positive with three Salmonella serovars: S. Virchow, S. Paratyphi B var Java (S. Java) and S. Enteritidis. Eleven of the 100 broiler farms investigated were positive for motile Salmonella, giving a farm-level prevalence of 11% (95% confidence interval 5-17%). S. Virchow and S. Kentucky were the two predominant serovars isolated from the broiler farms. The PFGE genotyping demonstrated that the isolates belonging to the same serovars were closely related due to variation in only 1-4 bands. All the S. Virchow and S. Java isolates, irrespective of breeder or broiler farm origin, were plasmid-free, except for one S. Virchow isolate from a broiler farm that harboured a 9.7 kb-sized plasmid. The S. Kentucky isolates belonged to three plasmid profiles having plasmids of four different sizes, ranging from 2.7 to 109 kb. This is the first report of any motile Salmonella serovars from breeder and commercial broiler poultry farms in Bangladesh.

  16. Backyard Farms Represent a Source of Wide Host Range Salmonella Phages That Lysed the Most Common Salmonella Serovars.

    Science.gov (United States)

    Rivera, Dácil; Toledo, Viviana; Pillo, Francisca DI; Dueñas, Fernando; Tardone, Rodolfo; Hamilton-West, Christopher; Vongkamjan, Kitiya; Wiedmann, Martin; Switt, Andrea I Moreno

    2018-02-01

    The genus Salmonella has more than 2,600 serovars, and this trait is important when considering interventions for Salmonella control. Bacteriophages that are used for biocontrol must have an exclusively lytic cycle and the ability to lyse several Salmonella serovars under a wide range of environmental conditions. Salmonella phages were isolated and characterized from 34 backyard production systems (BPSs) with a history of Salmonella infections. BPSs were visited once, and cloacal or fecal samples were processed for phage isolation. Four hosts, Salmonella serovars Enteritidis, Heidelberg, Infantis, and Typhimurium, were used for phage isolation. The host range of the phages was later characterized with a panel of 23 Salmonella serovars (serovar diversity set) and 31 isolates obtained from the same farms (native set). Genetic relatedness for 10 phages with a wide host range was characterized by restriction fragment length polymorphism, and phages clustered based on the host range. We purified 63 phages, and 36 phage isolates were obtained on Salmonella Enteritidis, 16 on Salmonella Heidelberg, and 11 on Salmonella Infantis. Phages were classified in three clusters: (i) phages with a wide host range (cluster I), (ii) phages that lysed the most susceptible Salmonella serovars (serogroup D) and other isolates (cluster II), and (iii) phages that lysed only isolates of serogroup D (cluster III). The most susceptible Salmonella serovars were Enteritidis, Javiana, and Dublin. Seven of 34 farms yielded phages with a wide host range, and these phages had low levels of genetic relatedness. Our study showed an adaptation of the phages in the sampled BPSs to serogroup D Salmonella isolates and indicated that isolation of Salmonella phages with wide host range differs by farm. A better understanding of the factors driving the Salmonella phage host range could be useful when designing risk-based sampling strategies to obtain phages with a wide lytic host range for biocontrol

  17. 40 CFR 174.505 - Bacillus thuringiensis modified Cry3A protein (mCry3A) in corn; exemption from the requirement of...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus thuringiensis modified Cry3A... of Bacillus thuringiensis modified Cry3A protein (mCry3A) in corn are exempt from the requirement of... REQUIREMENTS FOR PLANT-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.505 Bacillus...

  18. 40 CFR 174.519 - Bacillus thuringiensis Cry2Ab2 protein in corn and cotton; exemption from the requirement of a...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus thuringiensis Cry2Ab2 protein... Bacillus thuringiensis Cry2Ab2 protein in or on corn or cotton are exempt from the requirement of a... REQUIREMENTS FOR PLANT-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.519 Bacillus...

  19. Distribution of Bacillus thuringiensis subsp. israelensis in Soil of a Swiss Wetland Reserve after 22 Years of Mosquito Control▿†

    Science.gov (United States)

    Guidi, Valeria; Patocchi, Nicola; Lüthy, Peter; Tonolla, Mauro

    2011-01-01

    Recurrent treatments with Bacillus thuringiensis subsp. israelensis are required to control the floodwater mosquito Aedes vexans that breeds in large numbers in the wetlands of the Bolle di Magadino Reserve in Canton Ticino, Switzerland. Interventions have been carried out since 1988. In the present study, the spatial distribution of resting B. thuringiensis subsp. israelensis spores in the soil was measured. The B. thuringiensis subsp. israelensis concentration was determined in soil samples collected along six transects covering different elevations within the periodically flooded zones. A total of 258 samples were processed and analyzed by quantitative PCR that targeted an identical fragment of 159 bp for the B. thuringiensis subsp. israelensis cry4Aa and cry4Ba genes. B. thuringiensis subsp. israelensis spores were found to persist in soils of the wetland reserve at concentrations of up to 6.8 log per gram of soil. Continuous accumulation due to regular treatments could be excluded, as the decrease in spores amounted to 95.8% (95% confidence interval, 93.9 to 97.7%). The distribution of spores was correlated to the number of B. thuringiensis subsp. israelensis treatments, the elevation of the sampling point, and the duration of the flooding periods. The number of B. thuringiensis subsp. israelensis treatments was the major factor influencing the distribution of spores in the different topographic zones (P thuringiensis subsp. israelensis spores are rather immobile after their introduction into the environment. PMID:21498758

  20. 40 CFR 174.501 - Bacillus thuringiensis Vip3Aa protein in corn and cotton; exemption from the requirement of a...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus thuringiensis Vip3Aa protein... Bacillus thuringiensis Vip3Aa proteins in or on corn or cotton are exempt from the requirement of a... REQUIREMENTS FOR PLANT-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.501 Bacillus...

  1. 40 CFR 174.506 - Bacillus thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn; exemption from the requirement of...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus thuringiensis Cry34Ab1 and... Bacillus thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn are exempted from the requirement of a... REQUIREMENTS FOR PLANT-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.506 Bacillus...

  2. 40 CFR 174.510 - Bacillus thuringiensis Cry1Ac protein in all plants; 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 thuringiensis Cry1Ac protein... PLANT-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.510 Bacillus thuringiensis Cry1Ac protein in all plants; exemption from the requirement of a tolerance. Residues of Bacillus...

  3. 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...

  4. 40 CFR 174.511 - Bacillus thuringiensis Cry1Ab protein in all plants; 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 thuringiensis Cry1Ab protein... PLANT-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.511 Bacillus thuringiensis Cry1Ab protein in all plants; exemption from the requirement of a tolerance. Residues of Bacillus...

  5. The Synergist Effect of The Henna Plant, Lawsonia alba on Bacillus thuringiensis var. kurstaki Against Third Larval Instar of Pistachio Leaf Borer, Ocneria terebinthina Strg. (Lep.: Lymanteriidae

    Directory of Open Access Journals (Sweden)

    Zahra Sheibani

    2017-12-01

    Full Text Available Ocneria terebinthina Strg. (Lep.: Lymanteriidae is a leaf borer pest in pistachio orchard. The toxicity of Bacillus thuringiensis var. kurstaki alone and in combination with henna powder was investigated on third larval instar of O. terebinthina under laboratory conditions. Bioassay was carried out using spray technique on pistachio offshoot. Probit analysis of concentration-mortality data was conducted to estimate the LC50 value. The LC50 value of B. thuringiensis on third instar of larvae was estimated as 2817.30 ppm. The synergist effect of henna powder on efficacy of B. thuringiensis was also evaluated. Three concentrations of henna powder were combined with minimum lethal dose of B. thuringiensis against third larval instar. The results revealed that the henna powder had synergist effect on B. thuringiensis. The combination of B. thuringiensis and henna powder (6000 ppm caused 80.68% mortality, whereas B. thuringiensis alone caused 15.91% mortality. Our results suggested that henna powder can increase the efficacy of B. thuringiensis in controlling O. terebinthina in pest integrated management.

  6. Kajian Formulasi Bacillus thuringiensis Dengan Carrier Limbah Cair Pabrik Kelapa Sawit Untuk Pengendalian Ulat Api (Setora nitens

    Directory of Open Access Journals (Sweden)

    Dwi Wahyuono

    2015-02-01

    Full Text Available This research aims to examine palm oil effluent as a carrier for B. thuringiensis and its effectiveness against Setora nitens instar II-III in palm plantation. This research was held on April – December 2013 using single factor experiment method that has been arranging in completely randomized design (CRD. The research have two stages, first stage: development of B .thuringiensis and second stage: testing bioassay. First stage consist of three treatments that is 100%, 75%, 50% of Palm Oil Effluent and Luria Bertani Broth as a possitive control. Every treatment was added 0,4 g red sugar and 30 ml coconut water. the treatment in second stage same with first stage but use destilled water in addition treatment.  The parameter used are viability of B. thuringiensis, mortality (%, the speed of mortality, the change of population (%, and anti feedant (%. The result shown that palm oil effluent serve the purpose of alternative media of development B. Thuringiensis 7,6 x 107 CFU/ml. The optimal incubation period based of the toxcicity that is 48 hours. Formulation LCPKS 100% + 0,4 g red sugar + 30 ml coconut water + B. thuringiensis inclined more better based on the parameter of mortality, the change of population precentage, the speed of mortality amd anti feedant.

  7. Evidence of two mechanisms involved in Bacillus thuringiensis israelensis decreased toxicity against mosquito larvae: Genome dynamic and toxins stability.

    Science.gov (United States)

    Elleuch, Jihen; Zribi Zghal, Raida; Lacoix, Marie Noël; Chandre, Fabrice; Tounsi, Slim; Jaoua, Samir

    2015-07-01

    Biopesticides based on Bacillus thuringiensis israelensis are the most used and most successful around the world. This bacterium is characterized by a dynamic genome able to win or lose genetic materials which leads to a decrease in its effectiveness. The detection of such phenomena is of great importance to monitor the stability of B. thuringiensis strains in industrial production processes of biopesticides. New local B. thuringiensis israelensis isolates were investigated. They present variable levels of delta-endotoxins production and insecticidal activities against Aedes aegypti larvae. Searching on the origin of this variability, molecular and biochemical analyses were performed. The obtained results describe two main reasons of the decrease of B. thuringiensis israelensis insecticidal activity. The first reason was the deletion of cry4Aa and cry10Aa genes from the 128-kb pBtoxis plasmid as evidenced in three strains (BLB124, BLB199 and BLB506) among five. The second was the early degradation of Cry toxins by proteases in larvae midgut mainly due to some amino acids substitutions evidenced in Cry4Ba and Cry11Aa δ-endotoxins detected in BLB356. Before biological treatment based on B. thuringiensis israelensis, the studies of microflore in each ecosystem have a great importance to succeed pest management programs. Copyright © 2015 Elsevier GmbH. All rights reserved.

  8. Decolorization of textile dye RB19 using volcanic rock matrix immobilized Bacillus thuringiensis cells with surface displayed laccase.

    Science.gov (United States)

    Wan, Juan; Sun, Xiaowen; Liu, Cheng; Tang, Mengjun; Li, Lin; Ni, Hong

    2017-06-01

    A triplicate volcanic rock matrix-Bacillus thuringiensis-laccase WlacD (VRMs-Bt-WlacD) dye decolorization system was developed. WlacD was displayed on the B. thuringiensis MB174 cell surface to prepare a whole-cell laccase biocatalyst by using two repeat N-terminal domains of autolysin Mbg (Mbgn) 2 as the anchoring motif. Immunofluorescence microscopic assays confirmed that the fusion protein (Mbgn) 2 -WlacD was anchored on the surface of the recombinant B. thuringiensis MB174. After optimization by a single factor test, L 9 (3 4 )-orthogonal test, Plackett-Burman test, steepest ascent method, and Box-Behnken response surface methodology, the whole-cell specific laccase activity of B. thuringiensis MB174 was improved to 555.2 U L -1 , which was 2.25 times than that of the primary culture condition. Optimized B. thuringiensis MB174 cells were further adsorbed by VRMs to prepare VRMs-Bt-WlacD, an immobilized whole-cell laccase biocatalyst. Decolorization capacity of as-prepared VRMs-Bt-WlacD toward an initial concentration of 500 mg L -1 of an textile dye reactive blue 19 (RB19) aqueous solution reached 72.36% at a solid-to-liquid ratio of 10 g-100 mL. Repeated decolorization-activation operations showed the high decolorization capacity of VRMs-Bt-WlacD and have the potential for large-scale or continuous operations.

  9. The Homolog of the GenebstAof the BTP1 Phage from Salmonella enterica Serovar Typhimurium ST313 Is an Antivirulence Gene in Salmonella enterica Serovar Dublin.

    Science.gov (United States)

    Herrero-Fresno, Ana; Espinel, Irene Cartas; Spiegelhauer, Malene Roed; Guerra, Priscila Regina; Andersen, Karsten Wiber; Olsen, John Elmerdahl

    2018-01-01

    In a previous study, a novel virulence gene, bstA , identified in a Salmonella enterica serovar Typhimurium sequence type 313 (ST313) strain was found to be conserved in all published Salmonella enterica serovar Dublin genomes. In order to analyze the role of this gene in the host-pathogen interaction in S Dublin, a mutant where this gene was deleted ( S Dublin Δ bstA ) and a mutant which was further genetically complemented with bstA ( S Dublin 3246-C) were constructed and tested in models of in vitro and in vivo infection as well as during growth competition assays in M9 medium, Luria-Bertani broth, and cattle blood. In contrast to the results obtained for a strain of S Typhimurium ST313, the lack of bstA was found to be associated with increased virulence in S Dublin. Thus, S Dublin Δ bstA showed higher levels of uptake than the wild-type strain during infection of mouse and cattle macrophages and higher net replication within human THP-1 cells. Furthermore, during mouse infections, S Dublin Δ bstA was more virulent than the wild type following a single intraperitoneal infection and showed an increased competitive index during competitive infection assays. Deletion of bstA did not affect either the amount of cytokines released by THP-1 macrophages or the cytotoxicity toward these cells. The histology of the livers and spleens of mice infected with the wild-type strain and the S Dublin Δ bstA mutant revealed similar levels of inflammation between the two groups. The gene was not important for adherence to or invasion of human epithelial cells and did not influence bacterial growth in rich medium, minimal medium, or cattle blood. In conclusion, a lack of bstA affects the pathogenicity of S Dublin by decreasing its virulence. Therefore, it might be regarded as an antivirulence gene in this serovar. Copyright © 2017 American Society for Microbiology.

  10. RESIDUAL TOXICITY OF BACILLUS THURINGIENSIS H-14 (VCRC B17 IN SOME TYPES OF BREEDING PLACES OF AEDES AEGYPTI

    Directory of Open Access Journals (Sweden)

    Salamun Salamun

    2012-09-01

    Full Text Available Bacillus thuringiensis H-14, adalah agensia mikrobial yang sangat spesifik terhadap serangga sasaran, aman terhadap golongan mamalia, dan tidak mencemari lingkungan, sehingga dapat dikembangkan sebagai agensia untuk pengendalian vektor, khususnya vektor demam berdarah dengue di Indonesia. Toksisitas residual B. thuringiensis H-14 (VCRC B17 terhadap larva instar III Aedes aegypti pada beberapa tipe tempat penampung air telah dievaluasi di dalam laboratorium. Hasil evaluasi menunjukkan bahwa angka kematian larva uji lebih dari 80% oleh pengaruh B. thuringiensis H-14 (VCRC B17 pada konsentrasi antara 1 sampai 25 mg/l di dalam tipe tempat penampung air dari semen, tanah liat, dan plastik masing-masing adalah 16 sampai 60 hari, 18 sampai 36 hari, dan 12 sampai 42 hari.

  11. Selection of optimum conditions of medium acidity and aeration for submerget cultivation of Bacillus thuringiensis and Beauveria bassiana

    Directory of Open Access Journals (Sweden)

    O. A. Dregval

    2010-06-01

    Full Text Available The paper deals with the influence of medium pH and aeration rate on growth and sporulation of Bacillus thuringiensis and Вeauveria bassiana, which are main constituents of the complex microbial insecticide. It was established optimal medium pH for B. thuringiensis – 6.0 and for В. bassiana – 6.0–7.0. The maximum productivity of the studied microorganisms was observed in the same range of aeration – 7– 14 mmol O2/l/h. The selected conditions of cultivation are necessary for the production of complex biological insecticide based on the association of B. thuringiensis and B. bassiana.

  12. 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...

  13. Isolation of Bacillus thuringiensis from the state of Amazonas, in Brazil, and screening against Aedes aegypti (Diptera, Culicidae

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    Joelma Soares-da-Silva

    2015-03-01

    Full Text Available We investigated the use of Bacillus thuringiensis isolated in the state of Amazonas, in Brazil, for the biological control of the dengue vector Aedes aegypti. From 25 soil samples collected in nine municipalities, 484 bacterial colonies were obtained, 57 (11.78% of which were identified as B. thuringiensis. Six isolates, IBt-03, IBt-06, IBt-07, IBt-28, IBt-30, and BtAM-27 showed insecticidal activity, and only BtAM-27 presents the five genes investigated cry4Aa, cry4Ba, cry10Aa, cry11Aa, and cry11Ba. The IBt-07 and IBt- 28, with lower LC50 values, showed equal toxicity compared to the standards. The isolates of B. thuringiensis from Amazonas constitute potential new means of biological control for A. aegypti, because of their larvicidal activity and the possibility that they may also contain new combinations of toxins.

  14. Evaluation of Bacillus thuringiensis Pathogenicity for a Strain of the Tick, Rhipicephalus microplus, Resistant to Chemical Pesticides

    Science.gov (United States)

    Fernández-Ruvalcaba, Manuel; Peña-Chora, Guadalupe; Romo-Martínez, Armando; Hernández-Velázquez, Víctor; de Parra, Alejandra Bravo; De La Rosa, Diego Pérez

    2010-01-01

    The pathogenicity of four native strains of Bacillus thuringiensis against Rhipicephalus (Boophilus) microplus (Canestrine) (Acari: Ixodidae) was evaluated. A R. microplus strain that is resistant to organophosphates, pyrethroids, and amidines, was used in this study. Adult R. microplus females were bioassayed using the immersion test of Drummond against 60 B. thuringiensis strains. Four strains, GP123, GP138, GP130, and GP140, were found to be toxic. For the immersion test, the total protein concentration for each bacterial strain was 1.25 mg/ml. Mortality, oviposition, and egg hatch were recorded. All of the bacterial strains had significant effects compared to the controls, but no significant differences were seen between the 4 strains. It is evident that these B. thuringiensis strains have a considerable detrimental effect on the R. microplus strain that is resistant to pesticides. PMID:21062139

  15. Prevalence of Salmonella Isolates from Chicken and Pig Slaughterhouses and Emergence of Ciprofloxacin and Cefotaxime Co-Resistant S. enterica Serovar Indiana in Henan, China

    Science.gov (United States)

    Bai, Li; Lan, Ruiting; Zhang, Xiuli; Cui, Shenghui; Xu, Jin; Guo, Yunchang; Li, Fengqin; Zhang, Ding

    2015-01-01

    The prevalence of Salmonella from chicken and pig slaughterhouses in Henan, China and antimicrobial susceptibility of these isolates to antibiotics was determined. From 283 chicken samples and 240 pig samples collected, 128 and 70 Salmonella isolates were recovered with an isolation rate of 45.2 and 29.2% respectively. The predominant serovars in chicken samples were S. enterica serovar Enteritidis, S. enterica serovar Hadar and S. enterica serovar Indiana, while those in pig samples were S. enterica serovar Typhimurium, S. enterica serovar Derby and S. enterica serovar Enteritidis. Resistance to ciprofloxacin was 8.6 and 10.0% for isolates from chickens and pigs respectively, whereas resistance to cefotaxime was 5.5 and 8.6%, respectively. Multidrug resistance (resistance to three or more classes of antimicrobial agent) was markedly higher in pig isolates (57.1%) than in chicken isolates (39.8%). Of particular concern was the detection of ciprofloxacin and cefotaxime co-resistant S. enterica serovar Indiana isolates, which pose risk to public health. All 16 S. enterica serovar Indiana isolates detected were resistant to ciprofloxacin, among which 11 were co-resistant to cefotaxime. The S. enterica serovar Indiana isolates accumulated point mutations in quinolone resistance determination regions of gyrA (S83F/D87G or S83F/D87N) and parC (T57S/S80R). Two plasmid mediated quinolone resistant determinants were found with aac (6')-Ib-cr and oqxAB in 16 and 12 S. enterica serovar Indiana isolates respectively. Cefotaxime-resistance of S. enterica serovar Indiana was associated with the acquisition of a blaCTX-M-65 gene. The potential risk of ciprofloxacin and cefotaxime co-resistant S. enterica serovar Indiana infection is a significant concern due to limited alternative treatment options. Reduction of Salmonella in chicken and pig slaughterhouses, in particular, ciprofloxacin and cefotaxime co-resistant S. enterica serovar Indiana will be an important measure to reduce

  16. New Role for DCR-1/Dicer in Caenorhabditis elegans Innate Immunity against the Highly Virulent Bacterium Bacillus thuringiensis DB27

    Science.gov (United States)

    Iatsenko, Igor; Sinha, Amit; Rödelsperger, Christian

    2013-01-01

    Bacillus thuringiensis produces toxins that target invertebrates, including Caenorhabditis elegans. Virulence of Bacillus strains is often highly specific, such that B. thuringiensis strain DB27 is highly pathogenic to C. elegans but shows no virulence for another model nematode, Pristionchus pacificus. To uncover the underlying mechanisms of the differential responses of the two nematodes to B. thuringiensis DB27 and to reveal the C. elegans defense mechanisms against this pathogen, we conducted a genetic screen for C. elegans mutants resistant to B. thuringiensis DB27. Here, we describe a B. thuringiensis DB27-resistant C. elegans mutant that is identical to nasp-1, which encodes the C. elegans homolog of the nuclear-autoantigenic-sperm protein. Gene expression analysis indicated a substantial overlap between the genes downregulated in the nasp-1 mutant and targets of C. elegans dcr-1/Dicer, suggesting that dcr-1 is repressed in nasp-1 mutants, which was confirmed by quantitative PCR. Consistent with this, the nasp-1 mutant exhibits RNA interference (RNAi) deficiency and reduced longevity similar to those of a dcr-1 mutant. Building on these surprising findings, we further explored a potential role for dcr-1 in C. elegans innate immunity. We show that dcr-1 mutant alleles deficient in microRNA (miRNA) processing, but not those deficient only in RNAi, are resistant to B. thuringiensis DB27. Furthermore, dcr-1 overexpression rescues the nasp-1 mutant's resistance, suggesting that repression of dcr-1 determines the nasp-1 mutant's resistance. Additionally, we identified the collagen-encoding gene col-92 as one of the downstream effectors of nasp-1 that play an important role in resistance to DB27. Taken together, these results uncover a previously unknown role for DCR-1/Dicer in C. elegans antibacterial immunity that is largely associated with miRNA processing. PMID:23918784

  17. Emergence and clonal dissemination of Salmonella enterica serovar Enteritidis causing salmonellosis in Mauritius

    DEFF Research Database (Denmark)

    Issack, Mohammad I.; Hendriksen, Rene S.; Hyytiae-Trees, Eija

    2014-01-01

    Introduction: For decades, Salmonella enterica serovar Enteritidis has been among the most prevalent serovars reported worldwide. However, it was rarely encountered in Mauritius until 2007; since then the number of non-typhoidal Salmonella serogroup O:9 (including serovar Enteritidis) increased...... food specimens were characterized by antimicrobial susceptibility testing and Multiple-Locus Variable-number tandem repeat Analysis (MLVA). Results: With the exception of a single isolate which demonstrated intermediate susceptibility to streptomycin, all isolates were pansusceptible to the 14...... or closely related to blood and exudate isolates, indicating that, besides gastroenteritis, the same strain caused invasive infections. Control of S. Enteritidis by poultry breeders would lower the financial burden associated with morbidity in humans caused by this organism in Mauritius....

  18. Bacillus thuringiensis subsp. sichuansis strain MC28 produces a novel crystal protein with activity against Culex quinquefasciatus larvae.

    Science.gov (United States)

    Guan, Peng; Dai, Xiaojuan; Zhu, Jun; Li, Qiao; Li, Shuangcheng; Wang, Shiquan; Li, Ping; Zheng, Aiping

    2014-04-01

    The Bacillus thuringiensis subsp. sichuansis MC28 strain produces spherical parasporal crystals during sporulation and exhibits remarkable insecticidal activity against dipteran and lepidopteran pests. We characterized a novel cry gene (cry69Aa1), which was found in the pMC95 plasmid of the MC28 strain. The cry69Aa1 gene was inserted into a shuttle vector (pSTK) and expressed in an acrystalliferous mutant B. thuringiensis HD73⁻. In this transformant, a large number of spherical parasporal crystals, which were toxic to Culex quinquefasciatus (Diptera), were formed.

  19. Listeria prevalence and Listeria monocytogenes serovar diversity at cull cow and bull processing plants in the United States.

    Science.gov (United States)

    Guerini, Michael N; Brichta-Harhay, Dayna M; Shackelford, T Steven D; Arthur, Terrance M; Bosilevac, Joseph M; Kalchayanand, Norasak; Wheeler, Tommy L; Koohmaraie, Mohammad

    2007-11-01

    Listeria monocytogenes, the causative agent of epidemic and sporadic listeriosis, is routinely isolated from many sources, including cattle, yet information on the prevalence of Listeria in beef processing plants in the United States is minimal. From July 2005 through April 2006, four commercial cow and bull processing plants were sampled in the United States to determine the prevalence of Listeria and the serovar diversity of L. monocytogenes. Samples were collected during the summer, fall, winter, and spring. Listeria prevalence on hides was consistently higher during cooler weather (28 to 92% of samples) than during warmer weather (6 and 77% of samples). The Listeria prevalence data collected from preevisceration carcass ranged from undetectable in some warm season samples to as high as 71% during cooler weather. Listeria on postintervention carcasses in the chill cooler was normally undetectable, with the exception of summer and spring samples from one plant where > 19% of the carcasses were positive for Listeria. On hides, L. monocytogenes serovar 1/2a was the predominant serovar observed, with serovars 1/2b and 4b present 2.5 times less often and serovar 1/2c not detected on any hides sampled. L. monocytogenes serovars 1/2a, 1/2c, and 4b were found on postintervention carcasses. This prevalence study demonstrates that Listeria species are more prevalent on hides during the winter and spring and that interventions being used in cow and bull processing plants appear to be effective in reducing or eliminating Listeria contamination on carcasses.

  20. Human leptospirosis: occurrence of serovars of Leptospira spp. in the state of Minas Gerais, Brazil, from 2008 to 2012.

    Science.gov (United States)

    Oliveira, Marluce Aparecida Assunção; Leal, Élida Aparecida; Correia, Max Assunção; Serufo Filho, José Carlos; Dias, Ricardo Souza; Serufo, José Carlos

    Leptospirosis is an infectious and acute disease caused by Leptospira spp. that have high epidemic potential. This study verified the main Leptospira spp. serovars detected by MAT from serum of patients with suspicion of leptospirosis from 2008 to 2012 in Minas Gerais State. The laboratory received sera from 4654 patients. All serum were screened by IgM-ELISA according to the manufacturer's instructions. Each sample reactive or indeterminate were tested against twenty-four serovars of Leptospira by MAT. In this study, 597 patients were classified as reactive on MAT. Only 301 patients were confirmed by laboratory test. It was not possible confirmation by laboratory diagnosis of 296 patients. Among the samples classified as reactive on MAT, 273 patients exhibited titers bigger than 800 for one or more serovars; seroconversion was detected in 28 cases. Percentage of 85.1% of the samples reactive on MAT corresponded to males, 39.4% corresponded to patients aged between 20 and 39 years old. The most common serovars found were Icterohaemorrhagiae, Andamana, Patoc, Tarassovi, Copenhageni, Hardjo and Australis. Concerning the samples that exhibited titers bigger than 800, serovar Icterohaemorrhagiae was also the most common, followed by Copenhageni, Andamana, Patoc, Tarassovi, Grippotyphosa and Canicola. In this study, 40% of the cases occurred to the metropolitan area, state capital and 34 neighboring towns. Our results show the possibly spreading serovars in Minas Gerais State and contribute to knowledge of human leptospirosis, aiming at improving the prevention, control of the disease, as well as the treatment of infected patients. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  1. Isolation and characterization of polyvalent bacteriophages infecting multi drug resistant Salmonella serovars isolated from broilers in Egypt.

    Science.gov (United States)

    Mahmoud, Mayada; Askora, Ahmed; Barakat, Ahmed Barakat; Rabie, Omar El-Farouk; Hassan, Sayed Emam

    2018-02-02

    In this study, we isolated and characterized three phages named as Salmacey1, Salmacey2 and Salmacey3, infecting multi drug resistant Salmonella serovars isolated from broilers in Egypt. The most prevalent Salmonella serovars were S. typhimurium, S. enteritidis, and S. kentucky. All these Salmonella serovars were found to be resistant to more than two of the ten antimicrobial agents tested. Only S. kentucky was found to be resistant to seven antimicrobial agents. Examination of these phage particles by transmission electron microscopy (TEM), demonstrated that two phages (Salmacey1, Salmacey2) were found to belong to family Siphoviridae, and Salmacey3 was assigned to the family Myoviridae. The results of host range assay revealed that these bacteriophages were polyvalent and thus capable of infecting four strains of Salmonella serovars and Citrobacter freundii. Moreover, the two phages (Salmacey1, Salmacey2) had a lytic effect on Enterobacter cloacae and Salmacey3 was able to infect E. coli. All phages could not infect S. para Typhi, Staphylococus aureus and Bacillus cereus. One-step growth curves of bacteriophages revealed that siphovirus phages (Salmacey1, Salmacey2) have burst size (80 and 90pfu per infected cell with latent period 35min and 40min respectively), and for the myovirus Salmacey3 had a burst size 110pfu per infected cell with latent period 60min. Molecular analyses indicated that these phages contained double-stranded DNA genomes. The lytic activity of the phages against the most multidrug resistant serovars S. kentucky as host strain was evaluated. The result showed that these bacteriophages were able to completely stop the growth of S. kentucky in vitro. These results suggest that phages have a high potential for phage application to control Salmonella serovars isolated from broilers in Egypt. Copyright © 2017. Published by Elsevier B.V.

  2. Molecular identification of common Salmonella serovars using multiplex DNA sensor-based suspension array.

    Science.gov (United States)

    Aydin, Muhsin; Carter-Conger, Jacqueline; Gao, Ning; Gilmore, David F; Ricke, Steven C; Ahn, Soohyoun

    2018-04-01

    Salmonella is one of major foodborne pathogens and the leading cause of foodborne illness-related hospitalizations and deaths. It is critical to develop a sensitive and rapid detection assay that can identify Salmonella to ensure food safety. In this study, a DNA sensor-based suspension array system of high multiplexing ability was developed to identify eight Salmonella serovars commonly associated with foodborne outbreaks to the serotype level. Each DNA sensor was prepared by activating pre-encoded microspheres with oligonucleotide probes that are targeting virulence genes and serovar-specific regions. The mixture of 12 different types of DNA sensors were loaded into a 96-well microplate and used as a 12-plex DNA sensor array platform. DNA isolated from Salmonella was amplified by multiplex polymerase chain reaction (mPCR), and the presence of Salmonella was determined by reading fluorescent signals from hybridization between probes on DNA sensors and fluorescently labeled target DNA using the Bio-Plex® system. The developed multiplex array was able to detect synthetic DNA at the concentration as low as 100 fM and various Salmonella serovars as low as 100 CFU/mL within 1 h post-PCR. Sensitivity of this assay was further improved to 1 CFU/mL with 6-h enrichment. The array system also correctly and specifically identified serotype of tested Salmonella strains without any cross-reactivity with other common foodborne pathogens. Our results indicate the developed DNA sensor suspension array can be a rapid and reliable high-throughput method for simultaneous detection and molecular identification of common Salmonella serotypes.

  3. MARTX Toxin in the Zoonotic Serovar of Vibrio vulnificus Triggers an Early Cytokine Storm in Mice

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    Celia Murciano

    2017-07-01

    Full Text Available Vibrio vulnificus biotype 2-serovar E is a zoonotic clonal complex that can cause death by sepsis in humans and fish. Unlike other biotypes, Bt2 produces a unique type of MARTXVv (Multifunctional-Autoprocessive-Repeats-in-Toxin; RtxA13, which is encoded by a gene duplicated in the pVvBt2 plasmid and chromosome II. In this work, we analyzed the activity of this toxin and its role in human sepsis by performing in vitro, ex vivo, and in vivo assays. First, we demonstrated that the ACD domain, present exclusively in this toxin variant, effectively has an actin-cross-linking activity. Second, we determined that the whole toxin caused death of human endotheliocytes and monocytes by lysis and apoptosis, respectively. Finally, we tested the hypothesis that RtxA13 contributes to human death caused by this zoonotic serovar by triggering an early cytokine storm in blood. To this end, we used a Bt2-SerE strain (R99 together with its rtxA13 deficient mutant, and a Bt1 strain (YJ016 producing RtxA11 (the most studied MARTXVv together with its rtxA11 deficient mutant, as controls. Our results showed that RtxA13 was essential for virulence, as R99ΔΔrtxA13 was completely avirulent in our murine model of infection, and that R99, but not strain YJ016, induced an early, strong and dysregulated immune response involving the up-regulation of a high number of genes. This dysregulated immune response was directly linked to RtxA13. Based on these results and those obtained ex vivo (human blood, we propose a model of infection for the zoonotic serovar of V. vulnificus, in which RtxA13 would act as a sepsis-inducing toxin.

  4. Preliminary Investigations on the Distribution of Leptospira Serovars in Domestic Animals in North-west Morocco.

    Science.gov (United States)

    Benkirane, A; Noury, S; Hartskeerl, R A; Goris, M G A; Ahmed, A; Nally, J E

    2016-04-01

    Leptospirosis is a neglected zoonosis of global importance with a complex epidemiology that affects humans, domestic and wild mammals. However, due to the diversity of clinical signs and difficulties of establishing a confirmatory laboratory diagnosis, the disease remains poorly investigated, particularly in the developing world. In Morocco, a descriptive study of the seroprevalence of Leptospira infection in animals has never been undertaken. To fill this gap, the current study was conducted on a subset of animals in north-west Morocco as a preliminary step towards understanding the epidemiological patterns of animal leptospirosis in the country. The study was conducted on 289 serum samples collected between January and April 2012 from dogs, cattle, sheep, goats and donkeys in the areas of Rabat-Temara, Sidi Kacem and Oulmes. All serum samples were tested by the MAT with 14 reference strains of the most prevalent pathogenic serovars of Leptospira and two serovars of non-pathogenic Leptospira. The overall seroprevalence of Leptospira in cattle, sheep, goats, dogs and donkeys was 15%, 18%, 20%, 21% and 20%, respectively. The most prevalent serogroups found in each species were Ballum, Sejroe, and Australis in cattle, Ballum, Australis and Sejroe in sheep, Australis and Ballum in goats, Javanica and Australis in donkey and Australis, Ballum and Canicola in dogs. Of all the serogroups tested in this study, Icterohaemorrhagiae, the only serogroup which has been previously reported in humans in Morocco, was rarely reactive. The majority of reactive sera were collected from low land areas. A large number of sera samples classified as seronegative when tested against pathogenic leptospires were positive when tested against non-pathogenic leptospires; this is suggestive of possible novel, as yet unclassified, Leptospira serovars in Morocco. Eleven of thirteen sheep urine samples were positive by real-time PCR confirming their role as Leptospira carriers in Morocco. © 2014

  5. Leptospira interrogans serovar copenhageni harbors two lexA genes involved in SOS response.

    Directory of Open Access Journals (Sweden)

    Luciane S Fonseca

    Full Text Available Bacteria activate a regulatory network in response to the challenges imposed by DNA damage to genetic material, known as the SOS response. This system is regulated by the RecA recombinase and by the transcriptional repressor lexA. Leptospira interrogans is a pathogen capable of surviving in the environment for weeks, being exposed to a great variety of stress agents and yet retaining its ability to infect the host. This study aims to investigate the behavior of L. interrogans serovar Copenhageni after the stress induced by DNA damage. We show that L. interrogans serovar Copenhageni genome contains two genes encoding putative LexA proteins (lexA1 and lexA2 one of them being potentially acquired by lateral gene transfer. Both genes are induced after DNA damage, but the steady state levels of both LexA proteins drop, probably due to auto-proteolytic activity triggered in this condition. In addition, seven other genes were up-regulated following UV-C irradiation, recA, recN, dinP, and four genes encoding hypothetical proteins. This set of genes is potentially regulated by LexA1, as it showed binding to their promoter regions. All these regions contain degenerated sequences in relation to the previously described SOS box, TTTGN 5CAAA. On the other hand, LexA2 was able to bind to the palindrome TTGTAN10TACAA, found in its own promoter region, but not in the others. Therefore, the L. interrogans serovar Copenhageni SOS regulon may be even more complex, as a result of LexA1 and LexA2 binding to divergent motifs. New possibilities for DNA damage response in Leptospira are expected, with potential influence in other biological responses such as virulence.

  6. Epidemiology of a Salmonella enterica subsp. Enterica serovar Typhimurium strain associated with a songbird outbreak.

    Science.gov (United States)

    Blehert, David S.; Hernandez, Sonia M.; Keel, Kevin; Sanchez, Susan; Trees, Eija; ,

    2012-01-01

    Salmonella enterica subsp. enterica serovar Typhimurium is responsible for the majority of salmonellosis cases worldwide. This Salmonella serovar is also responsible for die-offs in songbird populations. In 2009, there was an S. Typhimurium epizootic reported in pine siskins in the eastern United States. At the time, there was also a human outbreak with this serovar that was associated with contaminated peanuts. As peanuts are also used in wild-bird food, it was hypothesized that the pine siskin epizootic was related to this human outbreak. A comparison of songbird and human S. Typhimurium pulsed-field gel electrophoresis (PFGE) patterns revealed that the epizootic was attributed not to the peanut-associated strain but, rather, to a songbird strain first characterized from an American goldfinch in 1998. This same S. Typhimurium strain (PFGE type A3) was also identified in the PulseNet USA database, accounting for 137 of 77,941 total S. Typhimurium PFGE entries. A second molecular typing method, multiple-locus variable-number tandem-repeat analysis (MLVA), confirmed that the same strain was responsible for the pine siskin epizootic in the eastern United States but was distinct from a genetically related strain isolated from pine siskins in Minnesota. The pine siskin A3 strain was first encountered in May 2008 in an American goldfinch and later in a northern cardinal at the start of the pine siskin epizootic. MLVA also confirmed the clonal nature of S. Typhimurium in songbirds and established that the pine siskin epizootic strain was unique to the finch family. For 2009, the distribution of PFGE type A3 in passerines and humans mirrored the highest population density of pine siskins for the East Coast.

  7. Genomic Comparison of Non-Typhoidal Salmonella enterica Serovars Typhimurium, Enteritidis, Heidelberg, Hadar and Kentucky Isolates from Broiler Chickens.

    Science.gov (United States)

    Dhanani, Akhilesh S; Block, Glenn; Dewar, Ken; Forgetta, Vincenzo; Topp, Edward; Beiko, Robert G; Diarra, Moussa S

    2015-01-01

    Non-typhoidal Salmonella enterica serovars, associated with different foods including poultry products, are important causes of bacterial gastroenteritis worldwide. The colonization of the chicken gut by S. enterica could result in the contamination of the environment and food chain. The aim of this study was to compare the genomes of 25 S. enterica serovars isolated from broiler chicken farms to assess their intra- and inter-genetic variability, with a focus on virulence and antibiotic resistance characteristics. The genomes of 25 S. enterica isolates covering five serovars (ten Typhimurium including three monophasic 4,[5],12:i:, four Enteritidis, three Hadar, four Heidelberg and four Kentucky) were sequenced. Most serovars were clustered in strongly supported phylogenetic clades, except for isolates of serovar Enteritidis that were scattered throughout the tree. Plasmids of varying sizes were detected in several isolates independently of serovars. Genes associated with the IncF plasmid and the IncI1 plasmid were identified in twelve and four isolates, respectively, while genes associated with the IncQ plasmid were found in one isolate. The presence of numerous genes associated with Salmonella pathogenicity islands (SPIs) was also confirmed. Components of the type III and IV secretion systems (T3SS and T4SS) varied in different isolates, which could explain in part, differences of their pathogenicity in humans and/or persistence in broilers. Conserved clusters of genes in the T3SS were detected that could be used in designing effective strategies (diagnostic, vaccination or treatments) to combat Salmonella. Antibiotic resistance genes (CMY, aadA, ampC, florR, sul1, sulI, tetAB, and srtA) and class I integrons were detected in resistant isolates while all isolates carried multidrug efflux pump systems regardless of their antibiotic susceptibility profile. This study showed that the predominant Salmonella serovars in broiler chickens harbor genes encoding adhesins

  8. Gonorrhoea: auxotypes, serovars, and clinical manifestations among female sex workers from Kinshasa, Zaïre.

    OpenAIRE

    Mukenge-Tshibaka, L; Alary, M; Van Dyck, E; Laga, M; Nzila, N

    1997-01-01

    The main question in this paper was to look at the distribution of auxotypes and serovars of Neisseria gonorrhoeae and check whether they correlate with clinical symptoms/signs among female sex workers (FSW) from Kinshasa, Zaïre. The subject were 1233 FSW enrolled in a cross sectional study on STDs and HIV infection in 1988; 771 of them were followed prospectively for a median duration of 23 months. At each visit, clinical symptoms and signs of cervicitis were recorded and the subjects were s...

  9. BIOCHEMICAL AND MOLECULAR CHARACTERIZATION OF SALMONELLA-ENTERICA SEROVAR BERTA, AND COMPARISON OF METHODS FOR TYPING

    DEFF Research Database (Denmark)

    Olsen, J. E.; Brown, D. J.; Baggesen, Dorte Lau

    1992-01-01

    Strains of Salmonella enterica serovar berta (S. berta) from Denmark and seven other countries have been characterized with the aim of developing a rational typing strategy in connection with outbreak investigations, Biotyping divided the strains into H2S-positive (90 %) and H2S-negative (10 %) b...... with restriction enzyme analysis of plasmids seemed to be the most rational typing strategy for S. berta. The results indicated that S. berta strains regardless of geographical source or host are possibly clonal in nature....

  10. Extended-Spectrum Cephalosporin-Resistant Salmonella enterica serovar Heidelberg Strains, the Netherlands1

    Science.gov (United States)

    Geurts, Yvon; Dierikx, Cindy M.; Brouwer, Michael S.M.; Kant, Arie; Wit, Ben; Heymans, Raymond; van Pelt, Wilfrid; Mevius, Dik J.

    2016-01-01

    Extended-spectrum cephalosporin-resistant Salmonella enterica serovar Heidelberg strains (JF6X01.0022/XbaI.0251, JF6X01.0326/XbaI.1966, JF6X01.0258/XbaI.1968, and JF6X01.0045/XbaI.1970) have been identified in the United States with pulsed-field gel electrophoresis. Our examination of isolates showed introduction of these strains in the Netherlands and highlight the need for active surveillance and intervention strategies by public health organizations. PMID:27314180

  11. Extended-Spectrum Cephalosporin-Resistant Salmonella enterica serovar Heidelberg Strains, the Netherlands(1).

    Science.gov (United States)

    Liakopoulos, Apostolos; Geurts, Yvon; Dierikx, Cindy M; Brouwer, Michael S M; Kant, Arie; Wit, Ben; Heymans, Raymond; van Pelt, Wilfrid; Mevius, Dik J

    2016-07-01

    Extended-spectrum cephalosporin-resistant Salmonella enterica serovar Heidelberg strains (JF6X01.0022/XbaI.0251, JF6X01.0326/XbaI.1966, JF6X01.0258/XbaI.1968, and JF6X01.0045/XbaI.1970) have been identified in the United States with pulsed-field gel electrophoresis. Our examination of isolates showed introduction of these strains in the Netherlands and highlight the need for active surveillance and intervention strategies by public health organizations.

  12. Detection and Molecular Characterization of Salmonella enterica Serovar Eppendorf Circulating in Chicken Farms in Tunisia.

    Science.gov (United States)

    Ben Salem, R; Abbassi, M S; García, V; García-Fierro, R; Njoud, C; Messadi, L; Rodicio, M R

    2016-06-01

    Salmonella enterica subsp. enterica serovar Eppendorf, with antigenic formula 1,4,12,[27]:d:1,5, is an infrequent serovar. However, 14% (20 of 142) of the isolates recovered during June-July 2012 in chicken farms in Tunisia belonged to S. Eppendorf. These isolates were analysed for resistance and virulence profiles. None of them were susceptible to all antimicrobials tested, while 70%, 60%, 50%, 50%, 20% and 5% were resistant to sulphonamides (sul1, sul2 and sul3), streptomycin (aadA1-like), trimethoprim (dfrA1-like), nalidixic acid (GyrA Asp87 →Asn and not identified), gentamicin (not identified) and ampicillin (blaTEM -1-like). About 30% of the isolates showed decreased susceptibility to ciprofloxacin and carried the qnrB gene; 65% of the isolates were multidrug resistant and contained class 1 integrons with sul1 or sul3 in the 3' conserved segment. The orgA, ssaQ, mgtC, siiD and sopB virulence genes located on SPI1 to SPI5 and the fimbrial bcfC gene were present in all isolates; the sopE1 and sodC1 carried by prophages were variably detected; however, the prophage gipA gene and the spvC gene of serovar-specific virulence plasmids were absent. Altogether, ten resistance and three virulence profiles were identified. Typing of the isolates with XbaI- and BlnI-PFGE supports a close relationship, although they appear to be evolving under selective pressure probably caused by antimicrobial use in chicken husbandry. As far as we know, this is the first study investigating the molecular bases of antimicrobial drug resistance, the virulence gene content and the PFGE profiles of S. Eppendorf. The epidemiological surveillance of this serovar would be necessary to evaluate its possible impact on human health, particularly in Tunisia and other African countries where it was already reported. © 2015 Blackwell Verlag GmbH.

  13. The Tricarballylate Utilization (tcuRABC) Genes of Salmonella enterica Serovar Typhimurium LT2

    OpenAIRE

    Lewis, Jeffrey A.; Horswill, Alexander R.; Schwem, Brian E.; Escalante-Semerena, Jorge C.

    2004-01-01

    The genes of Salmonella enterica serovar Typhimurium LT2 encoding functions needed for the utilization of tricarballylate as a carbon and energy source were identified and their locations in the chromosome were established. Three of the tricarballylate utilization (tcu) genes, tcuABC, are organized as an operon; a fourth gene, tcuR, is located immediately 5′ to the tcuABC operon. The tcuABC operon and tcuR gene share the same direction of transcription but are independently transcribed. The t...

  14. An epidemiological study of Salmonella enterica serovar 4, 12 : b :- in broiler chickens in Denmark

    DEFF Research Database (Denmark)

    Chadfield, M.; Skov, Marianne; Christensen, J.

    2001-01-01

    Epidemiological investigations of isolates of Salmonella enterica serovar 4, 12:b:- were carried out to establish particular molecular markers to assign isolates to a common origin. Plasmid profiling demonstrated that over 50% of 291 isolates, obtained between 1991 and 1996, were plasmid......-free. The remaining isolates exhibited a common trend in plasmid content of 105 and 2 kb. Although no specific correlation to any particular source within the poultry industry was discernible using plasmid analysis, there were indications of clonality with local divergence. Ribotyping with EcoRI demonstrated limited...

  15. BIOCHEMICAL AND MOLECULAR CHARACTERIZATION OF SALMONELLA-ENTERICA SEROVAR BERTA, AND COMPARISON OF METHODS FOR TYPING

    DEFF Research Database (Denmark)

    Olsen, J. E.; Brown, D. J.; Baggesen, Dorte Lau

    1992-01-01

    Strains of Salmonella enterica serovar berta (S. berta) from Denmark and seven other countries have been characterized with the aim of developing a rational typing strategy in connection with outbreak investigations, Biotyping divided the strains into H2S-positive (90 %) and H2S-negative (10...... with restriction enzyme analysis of plasmids seemed to be the most rational typing strategy for S. berta. The results indicated that S. berta strains regardless of geographical source or host are possibly clonal in nature....

  16. Salmonella serovars and antimicrobial resistance in strains isolated from wild animals in captivity in Sinaloa, Mexico.

    Science.gov (United States)

    Silva-Hidalgo, Gabriela; López-Valenzuela, Martin; Juárez-Barranco, Felipe; Montiel-Vázquez, Edith; Valenzuela-Sánchez, Beatriz

    2014-08-01

    The aim of the present study was to evaluate the frequency of antibiotic resistance in Salmonella spp. strains from wild animals in captivity at the Culiacan Zoo and the Mazatlan Aquarium in Sinaloa, Mexico. We identified 17 different Salmonella enterica serovars at a prevalence of 19.90% (Culiacan Zoo) and 6.25% (Mazatlan Aquarium). Antibiotic sensitivity tests revealed that, of the 83 strains studied, 100% were multidrug resistant (MDR). The drugs against which the greatest resistance was observed were: penicillin, erythromycin, dicloxacillin, ampicillin, cephalothin, and chloramphenicol. We therefore conclude that MDR is common among Salmonella isolates originating from wild animals in captivity in Sinaloa.

  17. Prevalence and antimicrobial resistance of Salmonella serovars isolated from poultry in Ghana.

    Science.gov (United States)

    Andoh, L A; Dalsgaard, A; Obiri-Danso, K; Newman, M J; Barco, L; Olsen, J E

    2016-11-01

    Poultry are possible sources of non-typhoidal Salmonella serovars which may cause foodborne human disease. We conducted a cross-sectional study to determine the prevalence of Salmonella serovars in egg-laying hens and broilers at the farm level and their susceptibility to antimicrobials commonly used in the poultry industry in Ghana. Sampling of faeces by a sock method (n = 75), dust (n = 75), feed (n = 10) and drinking water (n = 10) was performed at 75 commercial egg-laying and broiler farms in two regions of Ghana and skin neck (n = 30) at a local slaughterhouse from broilers representing different flocks. Salmonella was detected in 94/200 (47%) samples with an overall flock prevalence of 44·0%. Sixteen different serovars were identified with S. Kentucky (18·1%), S. Nima (12·8%), S. Muenster (10·6%), S. Enteritidis (10·6%) and S. Virchow (9·6 %) the most prevalent types. The predominant phage type of S. Enteritidis was PT1. All strains were susceptible to cefotaxime, ceftazidime and cefoxitin. Fifty-seven (60·6%) strains were resistant to one or more of the remaining nine antimicrobials tested by disk diffusion, of which 23 (40·4%) showed multi-resistance (resistance to ⩾3 classes of antimicrobials). Of the resistant strains (n = 57), the most significant were to nalidixic acid (89·5%), tetracycline (80·7%), ciprofloxacin (64·9%), sulfamethazole (42·1%), trimethoprim (29·8%) and ampicillin (26·3%). All S. Kentucky strains were resistant to more than two antimicrobials and shared common resistance to nalidixic acid or ciprofloxacin and tetracycline, often in combinations with other antimicrobials. PFGE analysis using XbaI of S. Kentucky demonstrated one dominant clone in the country. In conclusion, poultry produced in Ghana has a high prevalence of multi-resistant Salmonella and the common finding of clonal S. Kentucky in the Kumasi area warrants further investigations into the epidemiology of this serovar. There is an urgent need for surveillance

  18. Salmonella enterica serovars Typhimurium and Enteritidis causing mixed infections in febrile children in Mozambique

    Directory of Open Access Journals (Sweden)

    García V

    2018-01-01

    Full Text Available Vanesa García,1 Inácio Mandomando,2,3 Joaquim Ruiz,4 Silvia Herrera-León,5 Pedro L Alonso,3,4 M Rosario Rodicio1 1Departamento de Biología Funcional, Área de Microbiología, Universidad de Oviedo, Oviedo, Spain; 2Centro de Investigação em Saúde de Manhiça, 3Instituto Nacional de Saúde, Ministério da Saúde, Maputo, Mozambique; 4ISGlobal, Barcelona Centre for International Health Research, Hospital Clínic, Universitat de Barcelona, Barcelona, 5Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain Background and purpose: Invasive nontyphoidal salmonellosis, mostly caused by serovars Typhimurium and Enteritidis of Salmonella enterica, has emerged as a major public health problem in sub-Saharan Africa. The aim of this study was the clinical and microbiological characterization of nontyphoidal salmonellosis episodes affecting febrile children in Mozambique. Patients and methods: The clinical records of the patients were evaluated, and S. enterica isolates were characterized with regard to serovar, phage type, antimicrobial resistance (phenotype/responsible genes, plasmid content, pulsed-field gel electrophoresis, and multilocus sequence typing. Results: Fifteen S. Typhimurium and 21 S. Enteritidis isolates were recovered from blood samples of 25 children, the majority with underlying risk factors. With regard to phage typing, most isolates were either untypeable or reacted but did not conform, revealing that a number of previously unrecognized patterns are circulating in Mozambique. Most isolates were multidrug-resistant, with nearly all of the responsible genes located on derivatives of serovar-specific virulence plasmids. ST313 and ST11 were the predominant sequence types associated with S. Typhimurium and S. Enteritidis, respectively, and the uncommon ST1479 was also detected in S. Enteritidis. A distinct XbaI fragment of ~350 kb was associated with pulsed-field gel electrophoresis patterns of

  19. c-di-GMP Regulates Various Phenotypes and Insecticidal Activity of Gram-Positive Bacillus thuringiensis

    Directory of Open Access Journals (Sweden)

    Yang Fu

    2018-02-01

    Full Text Available C-di-GMP has been well investigated to play significant roles in the physiology of many Gram-negative bacteria. However, its effect on Gram-positive bacteria is less known. In order to more understand the c-di-GMP functions in Gram-positive bacteria, we have carried out a detailed study on the c-di-GMP-metabolizing enzymes and their physiological functions in Bacillus thuringiensis, a Gram-positive entomopathogenic bacterium that has been applied as an insecticide successfully. We performed a systematic study on the ten putative c-di-GMP-synthesizing enzyme diguanylate cyclases (DGCs and c-di-GMP-degrading enzyme phosphodiesterases (PDEs in B. thuringiensis BMB171, and artificially elevated the intracellular c-di-GMP level in BMB171 by deleting one or more pde genes. We found increasing level of intracellular c-di-GMP exhibits similar activities as those in Gram-negative bacteria, including altered activities in cell motility, biofilm formation, and cell-cell aggregation. Unexpectedly, we additionally found a novel function exhibited by the increasing level of c-di-GMP to promote the insecticidal activity of this bacterium against Helicoverpa armigera. Through whole-genome transcriptome profile analyses, we found that 4.3% of the B. thuringiensis genes were differentially transcribed when c-di-GMP level was increased, and 77.3% of such gene products are involved in some regulatory pathways not reported in other bacteria to date. In summary, our study represents the first comprehensive report on the c-di-GMP-metabolizing enzymes, their effects on phenotypes, and the transcriptome mediated by c-di-GMP in an important Gram-positive bacterium.

  20. c-di-GMP Regulates Various Phenotypes and Insecticidal Activity of Gram-Positive Bacillus thuringiensis

    Science.gov (United States)

    Fu, Yang; Yu, Zhaoqing; Liu, Shu; Chen, Bo; Zhu, Li; Li, Zhou; Chou, Shan-Ho; He, Jin

    2018-01-01

    C-di-GMP has been well investigated to play significant roles in the physiology of many Gram-negative bacteria. However, its effect on Gram-positive bacteria is less known. In order to more understand the c-di-GMP functions in Gram-positive bacteria, we have carried out a detailed study on the c-di-GMP-metabolizing enzymes and their physiological functions in Bacillus thuringiensis, a Gram-positive entomopathogenic bacterium that has been applied as an insecticide successfully. We performed a systematic study on the ten putative c-di-GMP-synthesizing enzyme diguanylate cyclases (DGCs) and c-di-GMP-degrading enzyme phosphodiesterases (PDEs) in B. thuringiensis BMB171, and artificially elevated the intracellular c-di-GMP level in BMB171 by deleting one or more pde genes. We found increasing level of intracellular c-di-GMP exhibits similar activities as those in Gram-negative bacteria, including altered activities in cell motility, biofilm formation, and cell-cell aggregation. Unexpectedly, we additionally found a novel function exhibited by the increasing level of c-di-GMP to promote the insecticidal activity of this bacterium against Helicoverpa armigera. Through whole-genome transcriptome profile analyses, we found that 4.3% of the B. thuringiensis genes were differentially transcribed when c-di-GMP level was increased, and 77.3% of such gene products are involved in some regulatory pathways not reported in other bacteria to date. In summary, our study represents the first comprehensive report on the c-di-GMP-metabolizing enzymes, their effects on phenotypes, and the transcriptome mediated by c-di-GMP in an important Gram-positive bacterium. PMID:29487570

  1. Bacillus thuringiensis monogenic strains: screening and interactions with insecticides used against rice pests

    Science.gov (United States)

    Pinto, Laura M.N.; Dörr, Natália C.; Ribeiro, Ana Paula A.; de Salles, Silvia M.; de Oliveira, Jaime V.; Menezes, Valmir G.; Fiuza, Lidia M.

    2012-01-01

    The screening of Bacillus thuringiensis (Bt) Cry proteins with high potential to control insect pests has been the goal of numerous research groups. In this study, we evaluated six monogenic Bt strains (Bt dendrolimus HD-37, Bt kurstaki HD-1, Bt kurstaki HD-73, Bt thuringiensis 4412, Bt kurstaki NRD-12 and Bt entomocidus 60.5, which codify the cry1Aa, cry1Ab, cry1Ac, cry1Ba, cry1C, cry2A genes respectively) as potential insecticides for the most important insect pests of irrigated rice: Spodoptera frugiperda, Diatraea saccharalis, Oryzophagus oryzae, Oebalus poecilus and Tibraca limbativentris. We also analyzed their compatibility with chemical insecticides (thiamethoxam, labdacyhalothrin, malathion and fipronil), which are extensively used in rice crops. The bioassay results showed that Bt thuringiensis 4412 and Bt entomocidus 60.5 were the most toxic for the lepidopterans, with a 93% and 82% mortality rate for S. frugiperda and D. saccharalis, respectively. For O. oryzae, the Bt kurstaki NRD-12 (64%) and Bt dendrolimus HD-37 (62%) strains were the most toxic. The Bt dendrolimus HD-37 strain also caused high mortality (82%) to O. poecilus, however the strains assessed to T. limbativentris caused a maximum rate of 5%. The assays for the Bt strains interaction with insecticides revealed the compatibility of the six strains with the four insecticides tested. The results from this study showed the high potential of cry1Aa and cry1Ba genes for genetic engineering of rice plants or the strains to biopesticide formulations. PMID:24031872

  2. c-di-GMP Regulates Various Phenotypes and Insecticidal Activity of Gram-PositiveBacillus thuringiensis.

    Science.gov (United States)

    Fu, Yang; Yu, Zhaoqing; Liu, Shu; Chen, Bo; Zhu, Li; Li, Zhou; Chou, Shan-Ho; He, Jin

    2018-01-01

    C-di-GMP has been well investigated to play significant roles in the physiology of many Gram-negative bacteria. However, its effect on Gram-positive bacteria is less known. In order to more understand the c-di-GMP functions in Gram-positive bacteria, we have carried out a detailed study on the c-di-GMP-metabolizing enzymes and their physiological functions in Bacillus thuringiensis , a Gram-positive entomopathogenic bacterium that has been applied as an insecticide successfully. We performed a systematic study on the ten putative c-di-GMP-synthesizing enzyme diguanylate cyclases (DGCs) and c-di-GMP-degrading enzyme phosphodiesterases (PDEs) in B. thuringiensis BMB171, and artificially elevated the intracellular c-di-GMP level in BMB171 by deleting one or more pde genes. We found increasing level of intracellular c-di-GMP exhibits similar activities as those in Gram-negative bacteria, including altered activities in cell motility, biofilm formation, and cell-cell aggregation. Unexpectedly, we additionally found a novel function exhibited by the increasing level of c-di-GMP to promote the insecticidal activity of this bacterium against Helicoverpa armigera . Through whole-genome transcriptome profile analyses, we found that 4.3% of the B. thuringiensis genes were differentially transcribed when c-di-GMP level was increased, and 77.3% of such gene products are involved in some regulatory pathways not reported in other bacteria to date. In summary, our study represents the first comprehensive report on the c-di-GMP-metabolizing enzymes, their effects on phenotypes, and the transcriptome mediated by c-di-GMP in an important Gram-positive bacterium.

  3. Isolation and characterization of a new Bacillus thuringiensis strain with a promising toxicity against Lepidopteran pests.

    Science.gov (United States)

    Boukedi, Hanen; Sellami, Sameh; Ktari, Sonia; Belguith-Ben Hassan, Najeh; Sellami-Boudawara, Tahya; Tounsi, Slim; Abdelkefi-Mesrati, Lobna

    2016-01-01

    Insecticides derived from Bacillus thuringiensis are gaining worldwide importance as environmentally desirable alternatives to chemicals for the control of pests in public health and agriculture. Isolation and characterization of new strains with higher and broader spectrum of activity is an ever growing field. In the present work, a novel Tunisian B. thuringiensis isolate named BLB459 was characterized and electrophoresis assay showed that among a collection of 200 B. thuringiensis strains, the plasmid profile of BLB459 was distinctive. SmaI-PFGE typing confirmed the uniqueness of the DNA pattern of this strain, compared with BUPM95 and HD1 reference strains. PCR and sequencing assays revealed that BLB459 harbored three cry genes (cry30, cry40 and cry54) corresponding to the obtained molecular sizes in the protein pattern. Interestingly, PCR-RFLP assay demonstrated the originality of the BLB459 cry30-type gene compared to the other published cry30 genes. Insecticidal bioassays showed that BLB459 spore-crystal suspension was highly toxic to both Ephestia kuehniella and Spodoptera littoralis with LC50 values of about 64 (53-75) and 80 (69-91) μg of toxin cm(-2), respectively, comparing with that of the commercial strain HD1 used as reference. Important histopathological effects of BLB459 δ-endotoxins on the two tested larvae midguts were detected, traduced by the vacuolization of the apical cells, the damage of microvilli, and the disruption of epithelial cells. These results proved that BLB459 strain could be of a great interest for lepidopteran biocontrol. Copyright © 2016 Elsevier GmbH. All rights reserved.

  4. A novel mosquitocidal Bacillus thuringiensis strain LLP29 isolated from the phylloplane of Magnolia denudata

    Czech Academy of Sciences Publication Activity Database

    Zhang, L.; Huang, E.; Lin, J.; Gelbič, Ivan; Zhang, Q.; Guan, Y.; Huang, T.; Guan, X.

    2010-01-01

    Roč. 165, č. 2 (2010), s. 133-141 ISSN 0944-5013 R&D Projects: GA MŠk 2B08003 Grant - others:United Fujian Provincial Health and Education Project for Tackling Key Research(CN) WKJ2008-2-44; Talented Youth Project of Fujian Province(CN) 2008F3012; Educational Department of Fujian Province(CN) JA08080; Fujian Agriculture and Forestry University(CN) 08A01 Institutional research plan: CEZ:AV0Z50070508 Keywords : Bacillus thuringiensis * cyt1 * mosquito Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection Impact factor: 1.958, year: 2010

  5. Sensitivity of the bacterium Bacillus Thuringiensis as an insect disease agent to gamma-rays

    International Nuclear Information System (INIS)

    Merdam, A.I.; Abdu, R.M.

    1977-01-01

    The effect of gamma radiation on the viability of the entomopathogenic spore-forming bacterium, Bacillus thuringiensis, was tested. The different gamma doses varied much in their effect on such bacterium. All irradiated Bacillus suspensions with doses below 85 krad showed different degrees of inhibitory activity. However, bacterial suspensions irradiated at a dose of 90 krad. proved to promote spore germination. Changes in the physiological, and morphological characters of the irradiated Bacillus at these levels were detected. The new observed characters were induced at a particular dose level of 90 krad. These new characters are assumed to be due to genetic changes induced at this particular gamma dose

  6. Comparative Genomics of Bacillus thuringiensis Reveals a Path to Specialized Exploitation of Multiple Invertebrate Hosts.

    Science.gov (United States)

    Zheng, Jinshui; Gao, Qiuling; Liu, Linlin; Liu, Hualin; Wang, Yueying; Peng, Donghai; Ruan, Lifang; Raymond, Ben; Sun, Ming

    2017-08-08

    Understanding the genetic basis of host shifts is a key genomic question for pathogen and parasite biology. The Bacillus cereus group, which encompasses Bacillus thuringiensis and Bacillus anthracis , contains pathogens that can infect insects, nematodes, and vertebrates. Since the target range of the essential virulence factors (Cry toxins) and many isolates is well known, this group presents a powerful system for investigating how pathogens can diversify and adapt to phylogenetically distant hosts. Specialization to exploit insects occurs at the level of the major clade and is associated with substantial changes in the core genome, and host switching between insect orders has occurred repeatedly within subclades. The transfer of plasmids with linked cry genes may account for much of the adaptation to particular insect orders, and network analysis implies that host specialization has produced strong associations between key toxin genes with similar targets. Analysis of the distribution of plasmid minireplicons shows that plasmids with orf156 and orf157 , which carry genes encoding toxins against Lepidoptera or Diptera, were contained only by B. thuringiensis in the specialized insect clade (clade 2), indicating that tight genome/plasmid associations have been important in adaptation to invertebrate hosts. Moreover, the accumulation of multiple virulence factors on transposable elements suggests that cotransfer of diverse virulence factors is advantageous in terms of expanding the insecticidal spectrum, overcoming insect resistance, or through gains in pathogenicity via synergistic interactions between toxins. IMPORTANCE Population genomics have provided many new insights into the formation, evolution, and dynamics of bacterial pathogens of humans and other higher animals, but these pathogens usually have very narrow host ranges. As a pathogen of insects and nematodes, Bacillus thuringiensis , which produces toxins showing toxicity to many orders of insects and

  7. [Experiments with Bacillus thuringiensis protoplasts. I. Isolation of protoplasts and their reversion to bacillary form].

    Science.gov (United States)

    Tsenin, A N; Nesterenko, A V; Rybchin, V N; Potokin, I L; Pisarevskiĭ, Iu S

    1983-04-01

    A method for protoplastization of crystal- and spore-forming Bacillus thuringiensis bacterian and consequent cell wall regeneration on a solid hypertonic medium is presented. Up to 50% of the protoplasts prepared were viable and formed colonies under special conditions; at the same time, less than 0,01% of the cells treated with lysozyme were resistant to the osmotic shock; bacterial autolytic system takes part in protoplasts formation. Electron microscopic studies of protoplasts and cells confirm the fact of cell wall removal and support the proposed mechanism of protoplast formation.

  8. Distinct clpP Genes Control Specific Adaptive Responses in Bacillus thuringiensis

    OpenAIRE

    Fedhila, Sinda; Msadek, Tarek; Nel, Patricia; Lereclus, Didier

    2002-01-01

    ClpP and ClpC are subunits of the Clp ATP-dependent protease, which is ubiquitous among prokaryotic and eukaryotic organisms. The role of these proteins in stress tolerance, stationary-phase adaptive responses, and virulence in many bacterial species has been demonstrated. Based on the amino acid sequences of the Bacillus subtilis clpC and clpP genes, we identified one clpC gene and two clpP genes (designated clpP1 and clpP2) in Bacillus thuringiensis. Predicted proteins ClpP1 and ClpP2 have ...

  9. Avances en el desarrollo de formulaciones insecticidas a base de bacillus thuringiensis

    OpenAIRE

    Rosas-García, Ninfa María

    2008-01-01

    El desarrollo de las formulaciones insecticidas elaboradas a base de la bacteria Bacillus thuringiensis es una tecnología centenaria que ha recibido un fuerte impacto en décadas recientes. La mezcla de esporas y cristales, que es el principio activo de estas preparaciones, ha sido objeto de estudio constante y en ello se destaca la búsqueda de cepas cada vez más potentes o mejoradas. Así mismo, los materiales utilizados incluyen una amplia variedad de ingredientes completamente biodegradables...

  10. Isolation of strains of Bacillus thuringiensis insecticidal biological activity against Ceratitis capitata

    International Nuclear Information System (INIS)

    Hmaied, Ezzedine; Ben Mbarek, Wael

    2010-01-01

    The present work is to study the effect of toxins (δ-endotoxins) extracted from strains of Bacillus thuringiensis isolated from the mud on the fly Sabkhat Dejoumi Ceratitis capitata, a pest of citrus and fruit trees. Among 51 isolated tested, 15 showed a very significant insecticidal activity, characterized by mortality rates exceeding 80 pour cent. These mortality rates are caused by endotoxins of Bt revealed variability between them. The preliminary results of this study encourage us towards the characterization of the insecticidal activity produced by strains of Bt for large scale application.

  11. 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

    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...... 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...

  12. Potency of Bacillus thuringiensis isolates from bareng Tenes-Malang City as a biological control agent for suppressing third instar of Aedes aegypti larvae

    Science.gov (United States)

    Lutfiana, Nihayatul; Gama, Zulfaidah Penata

    2017-11-01

    Dengue is a mosquito-borne viral disease that is transmitted by the female Aedes species. The number of dengue fever cases has increased in many geographic regions including Indonesia and one of them occurred in Bareng Tenes, Malang City, East Java Province. The objective of this research was to identify the potency of B. thuringeinsis isolates from Bareng Tenes, Malang, as the biological agent to control third instar Ae. aegypti larvae and to identify the potential B. thuringiensis isolates based on 16S rDNA sequence. B. thuringiensis was isolated from water and soil from 12 sites in the Bareng Tenes area. Bacterial isolation was performed using B. thuringiensis selective media. Several isolates had similar phenotypic characters with B. thuringiensis used to toxicity test against third instar Ae. aegypti larvae. The LC50-96h value was determined using probit regression. The most effective isolate was identified based on the 16S rDNA sequence, then aligned to the reference isolate using the BLAST program. A phylogeny tree was constructed using the Maximum Likelihood method. This study showed that among 22 isolates of B. thuringiensis, only BA02b, BS04a, and BA03a isolates have similar phenotypic characters with B. thuringiensis. Based on the toxicity test of B. thuringiensis against the third instar of Ae. aegypti larvae, it was indicated that BA02b and BA03a isolates were the potential agents to control Ae. aegypti larvae. BA02b isolate was the most effective B. thuringiensis (LC50-96h = 2,75 x 107 cell/mL). Based on 16S rDNA sequence, BA02b was identified as Bacillus thuringiensis var. Israelensis BGSC4Q2 (99 % similarities).

  13. EFEKTIVITAS Bacillus thuringiensis H-14 STRAIN LOKAL DALAM BUAH KELAPA TERHADAP LARVA Anopheles sp dan Culex sp di KAMPUNG LAUT KABUPATEN CILACAP

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    Blondine Ch. P

    2013-07-01

    Full Text Available Abstrak Bacillus thuringiensis serotipe H-14 strain lokal adalah bakteri patogen bersifat target spesifiknya larva nyamuk, aman bagi mamalia dan lingkungan. Penelitian bertujuan menentukan efektivitas B. thuringiensis H-14 strain lokal yang dikembangbiakkan dalam buah kelapa untuk pengendalian larva Anopheles sp dan Culex sp. Rancangan eksperimental semu, terdiri dari kelompok perlakuan dan kontrol. Bacillus thuringiensis H-14 strain lokal dikembangbiakan dalam10 buah kelapa umur 6–8 bulan, dengan berat kira-kira 1 kg, telah berisi air kelapa sekitar 400-500 ml/buah kelapa yang diperoleh dari Desa Klaces, Kampung Laut, Kabupaten Cilacap. Diinkubasi selama 14 hari pada temperatur kamar dan ditebarkan di 6 kolam yang menjadi habitat perkembangbiakan larva nyamuk dengan luas berkisar 3–100 m2.Hasil yang diperoleh menunjukkan efektivitas B. thuringiensis H-14 strain lokal terhadap larva Anopheles sp dan Culex sp selama 1 hari sesudah penebaran kematian larva berturut-turut sebesar 80–100% dan 79,31–100%. Sedangkan pada hari ke-14 sebesar 69,30–76,71% dan 67,69–86,04%. Buah kelapa dapat digunakan sebagai media lokal alternatif untuk pengembangbiakan B. thuringiensis H-14 strain lokal Kata kunci: B. thuringiensis H-14,  strain  lokal, buah kelapa, pengendalian larva Abstract Bacillus thuringiensis serotype H-14 local strain is pathogenic bacteria which specific  target to mosquito larvae. It is safe for mammals and enviroment. The aims of this study was to determine the effectivity of B. thuringiensis H-14 local strain which culturing in thecoconut wates against Anopheles sp and Culex sp mosquito larvae. This research is quasi experiment which consist of treated  and control groups. Bacillus thuringiensis H-14 local strain was cultured in 10 coconuts with 6–8 months age with weight around 1 kg that contained were approximately 400-500 ml/coconut were taken from Klaces village, Kampung Laut. After that the coconuts incubated for 14

  14. The importance of Leptospira interrogans serovars Icterohaemorrhagiae and Canicola in coastal zone and in southern fields of Rio Grande do Sul, Brazil

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    Felipe J. Silva

    2014-01-01

    Full Text Available This study aimed to describe the occurrence of Leptospira interrogans serovars Icterohaemorrhagiae and Canicola, in coastal zone and in southern grasslands of Rio Grande do Sul, Brazil. In each one of the four analyzed farms blood samples were collected from free-living wild animals, domestic animals and humans to perform serological testing for leptospirosis. The presence of antibodies was verified by microscopic agglutination test (MAT. The criterion adopted to consider a serum as agglutination reactant was at least 50% of leptospira for a microscopic field of 100x. From 17 blood samples collected at Chuí, five (29.41% were positive, three (60.00% for serovar Icterohaemorrhagiae and two (40.00% for Canicola. From 21 samples collected in the County of Santana da Boa Vista, six (28.57% were positive, four (66.67% for serovar Canicola and two (33.33% for serovar Icterohaemorrhagiae. From 32 samples collected at Alegrete, 10 (31.25% were positive, seven (70.00% for serovar Icterohaemorrhagiae and three (30.00% foro serovar Canicola. From 17 blood samples collected in Cruz Alta, three (17.64% were positive, two (66.67% for serovar Icterohaemorrhagiae and one (33.33% for Canicola. It is necessary to improve sanitary practices on farms in the state of Rio Grande do Sul, in order to achieve success in leptospirosis control programs.

  15. Physiological and Immunological Regulations in Caenorhabditis elegans Infected with Salmonella enterica serovar Typhi.

    Science.gov (United States)

    Sivamaruthi, Bhagavathi Sundaram; Balamurugan, Krishnaswamy

    2014-03-01

    Studies pertaining to Salmonella enterica serovar Typhimurium infection by utilizing model systems failed to mimic the essential aspects of immunity induced by Salmonella enterica serovar Typhi, as the determinants of innate immunity are distinct. The present study investigated the physiological and innate immune responses of S. Typhi infected Caenorhabditis elegans and also explored the Ty21a mediated immune enhancement in C. elegans. Ty21a is a known live vaccine for typhoidal infection in human beings. Physiological responses of C. elegans infected with S. Typhi assessed by survival and behavioral assays revealed that S. Typhi caused host mortality by persistent infection. However, Ty21a exposure to C. elegans was not harmful. Ty21a pre-exposed C. elegans, exhibited significant resistance against S. Typhi infection. Elevated accumulation of S. Typhi inside the infected host was observed when compared to Ty21a exposures. Transcript analysis of candidate innate immune gene (clec-60, clec-87, lys-7, ilys-3, scl-2, cpr-2, F08G5.6, atf-7, age-1, bec-1 and daf-16) regulations in the host during S. Typhi infection have been assessed through qPCR analysis to understand the activation of immune signaling pathways during S. Typhi infections. Gene silencing approaches confirmed that clec-60 and clec-87 has a major role in the defense system of C. elegans during S. Typhi infection. In conclusion, the study revealed that preconditioning of host with Ty21a protects against subsequent S. Typhi infection.

  16. First outbreak of food poisoning caused by Salmonella enterica subspecies enterica serovar Berta in Italy.

    Science.gov (United States)

    Di Giannatale, E; Sacchini, L; Persiani, T; Alessiani, A; Marotta, F; Zilli, K

    2012-08-01

    To provide an epidemiologic interpretation of a suspected outbreak of food poisoning caused by Salmonella enterica subspecies enterica serovar Berta strains isolated from humans and from the leftovers of the implicated foods (cream, dairy-based desserts and eggs). We have correlated the similarity between the strains through genotyping with Pulsed Field Gel Electrophoresis (PFGE), studying antimicrobial sensitivity patterns and epidemiological investigation. The clonal origin of the outbreak was confirmed by all laboratory tests. PFGE analysis of the restriction profiles obtained with XbaI and SpeI revealed a certainly correlation from the strains isolated from the various sources, while the antimicrobial sensitivity pattern was the same in all cases, with all strains sensitive to all antibiotics tested. Poor hygiene conditions in the facility concerned, lack of hygiene in food handling, high summer temperatures and positive cultures from asymptomatic staff could all be implicated in the infection, with food being the means through which it spread. This study describes the first outbreak of food poisoning caused by Salmonella enterica subspecies enterica serovar Berta (Salmonella Berta) reported in Italy. It confirms the importance of correlating epidemiological investigations with genotyping and phenotyping to understand the dynamics of infection. © 2012 The Authors. Letters in Applied Microbiology © 2012 The Society for Applied Microbiology.

  17. Cattle-derived Salmonella enterica serovar Dublin Infections in Red Foxes ( Vulpes vulpes ) in Tyrol, Austria.

    Science.gov (United States)

    Glawischnig, Walter; Lazar, Judit; Wallner, Alice; Kornschober, Christian

    2017-04-01

    Salmonella enterica serovar Dublin is endemic in the cattle population in some areas of the Austrian province Tyrol, and each year single dairy farms have experienced clinical infections. To ascertain if Tyrolean red foxes ( Vulpes vulpes ) act as a reservoir for Salmonella spp., we tested hepatic tissue and intestinal content from foxes hunted in the years 2015-16 by using microbiological methods. In addition, we included several fox fecal samples collected on a mountain pasture near chamois carcasses in the investigation. Of 434 foxes tested, nine animals (2.1%) were positive for Salmonella spp. Serotyping revealed five foxes positive with S. Dublin, demonstrating that this serovar exists in the Tyrolean fox population. The fecal samples collected in the area surrounding skeletonized chamois ( Rupicapra rupicapra ) also tested positive for S. Dublin. These chamois were probably victims of a waterborne outbreak caused by S. Dublin-shedding cattle. Our results indicate that the S. Dublin infections in red foxes were primarily acquired through ingestion of infected cattle material such as abortion tissues, but also by feeding on dead chamois. The findings underline the importance of interspecies transmission in this domestic/wildlife interface.

  18. Lack of efflux mediated quinolone resistance in Salmonella enterica serovars Typhi and Paratyphi A

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    Sylvie eBaucheron

    2014-01-01

    Full Text Available Salmonella enterica serovars Typhi and Paratyphi A isolates from human patients in France displaying different levels of resistance to quinolones or fluoroquinolones were studied for resistance mechanisms to these antimicrobial agents. All resistant isolates carried either single or multiple target gene mutations (i.e. in gyrA, gyrB, or parC correlating with the resistance levels observed. Active efflux, through upregulation of multipartite efflux systems, has also been previously reported as contributing mechanism for other serovars. Therefore, we investigated also the occurrence of non-target gene mutations in regulatory regions affecting efflux pump expression. However, no mutation was detected in these regions in both Typhi and Paratyphi isolates of this study. Besides, no overexpression of the major efflux systems was observed for these isolates. Nevertheless, a large deletion of 2334 bp was identified in the acrS-acrE region of all S. Typhi strains but which did not affect the resistance phenotype. As being specific to S. Typhi, this deletion could be used for specific molecular detection purposes. In conclusion, the different levels of quinolone or FQ resistance in both S. Typhi and S. Paratyphi A seem to rely only on target modifications.

  19. Three case studies involving Leptospira interrogans serovar pomona infection in mixed farming units : case report

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    B. Gummow

    1999-07-01

    Full Text Available Three case studies involving Leptospira interrogans serovar pomona outbreaks within mixed farming systems in South Africa are described. On 2 farms, pigs constituted the main enterprise with cattle and sheep of secondary importance. On each of these 2 farms, abortion due to L. pomona in sows was confirmed by culture, and antibody titres to pomona were detected in cattle, sheep, horses and dogs. On the 3rd farm, a piggery was ofsecondary importance to cattle farming. Abortion and death in cows occurred on this farmand serology showed titres to various serovars, including pomona. L. pomona was also isolated from bovine urine, an aborted bovine foetus and kidneys from slaughtered pigs. This particular case study was regarded as clinically atypical in that adult Jersey cattle died of acute leptospirosis in a semiarid region of South Africa. In all 3 case studies, the poor management of pig effluent and of the drinking water and its sources played a pivotal role in the transmission of the disease. Inadequate vaccination of animals against Leptospira and poor record-keeping within the secondary farming enterprises were also contributing factors to the spread of leptospirosis.

  20. Requirement for cobalamin by Salmonella enterica serovars Typhimurium, Pullorum, Gallinarum and Enteritidis during infection in chickens

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    Jacqueline Boldrin de Paiva

    2011-12-01

    Full Text Available Salmonella enterica serovar Typhimurium synthesizes cobalamin (vitamin B12 only during anaerobiosis. Two percent of the S. Typhimurium genome is devoted to the synthesis and uptake of vitamin B12 and to B12-dependent reactions. To understand the requirement for cobalamin synthesis better, we constructed mutants of Salmonella serovars Enteritidis and Pullorum that are double-defective in cobalamin biosynthesis (ΔcobSΔcbiA. We compared the virulence of these mutants to that of their respective wild type strains and found no impairment in their ability to cause disease in chickens. We then assessed B12 production in these mutants and their respective wild type strains, as well as in S. Typhimurium ΔcobSΔcbiA, Salmonella Gallinarum ΔcobSΔcbiA, and their respective wild type strains. None of the mutants was able to produce detectable B12. B12 was detectable in S. Enteritidis, S. Pullorum and S. Typhimurium wild type strains but not in S. Gallinarum. In conclusion, the production of vitamin B12 in vitro differed across the tested Salmonella serotypes and the deletion of the cbiA and cobS genes resulted in different levels of alteration in the host parasite interaction according to Salmonella serotype tested.

  1. The effect of nitric oxide combined with fluoroquinolones against Salmonella enterica serovar Typhimurium in vitro

    Directory of Open Access Journals (Sweden)

    Coban AY

    2003-01-01

    Full Text Available Two regulons, soxRS and marRAB, are associated with resistance to quinolones or multiple antibiotic in Salmonella enterica serovar Typhimurium. These regulons are activated by nitric oxide and redox-cycling drugs, such as paraquat and cause on activation of the acrAB-encoded efflux pump. In this study, we investigated the effect of nitric oxide (NO alone and in combination with ofloxacin, ciprofloxacin, and pefloxacin against S. typhimurium clinical isolates and mutant strains in vitro. We did not observe synergistic effect against clinical isolates and SH5014 (parent strain of acr mutant, while we found synergistic effect against PP120 (soxRS mutant and SH7616 (an acr mutant S. typhimurium for all quinolones. Our results suggest that the efficiencies of some antibiotics, including ofloxacin, ciprofloxacin, and pefloxacin are decreased via activation of soxRS and marRAB regulons by NO in S. enterica serovar Typhimurium. Further studies are warranted to establish the interaction of NO with the genes of Salmonella and, with multiple antibiotic resistance.

  2. Characterization of Tunisian Bacillus thuringiensis strains with abundance of kurstaki subspecies harbouring insecticidal activities against the lepidopteran insect Ephestia kuehniella.

    Science.gov (United States)

    Saadaoui, Imen; Al-Thani, Roda; Al-Saadi, Fatma; Belguith-Ben Hassan, Najeh; Abdelkefi-Mesrati, Lobna; Schultz, Patrick; Rouis, Souad; Jaoua, Samir

    2010-12-01

    The study of 257 crystal-producing Bacillus thuringiensis isolates from bioinsecticide free soil samples collected from different sites in Tunisia, was performed by PCR amplification, using six primer pairs specific for cry1, cry2, cry3, cry4, and vip3A genes, by the investigation of strain plasmid pattern, crystal morphology and delta-endotoxin content and by the assessment of insecticidal activities against the lepidopteran insect Ephestia kuehniella. Based on plasmid pattern study, 11 representative strains of the different classes were subjected to morphological and molecular analyses. The comparison of the PFGE fingerprints confirmed the heterogeneity of these strains. B. thuringiensis kurstaki strains, harbouring at the same time the genes cry1A, cry2, cry1Ia, and vip3A, were the most abundant (65.4%). 33.34% of the new isolates showed particular delta-endotoxin profiles but no PCR products with the used primer sets. B. thuringiensis israelensis was shown to be also very rare among the Tunisian B. thuringiensis isolates diversity. These findings could have considerable impacts for the set up of new pest control biological agents.

  3. Bacillus thuringiensis Cry1Ca-resistant Spodoptera exigua lacks expression of one of four Aminopeptidase N genes

    NARCIS (Netherlands)

    Herrero, S.; Gechev, T.; Bakker, P.L.; Moar, W.; Maagd, de R.A.

    2005-01-01

    BACKGROUND: Insecticidal toxins from Bacillus thuringiensis bind to receptors on midgut epithelial cells of susceptible insect larvae. Aminopeptidases N (APNs) from several insect species have been shown to be putative receptors for these toxins. Here we report the cloning and expression analysis of

  4. A hybrid Bacillus thuringiensis delta-endotoxin gene gives resistance against a coleopteran and a lepidopteran pest in transgenic potato

    NARCIS (Netherlands)

    Naimov, S.; Dukiandjiev, S.; Maagd, de R.A.

    2003-01-01

    Expression of Bacillus thuringiensis delta-endotoxins has proven to be a successful strategy for obtaining insect resistance in transgenic plants. Drawbacks of expression of a single resistance gene are the limited target spectrum and the potential for rapid adaptation of the pest. Hybrid toxins

  5. Characterization of the pH-Mediated solubility of Bacillus thuringiensis var. san diego native δ-endotoxin crystals

    Science.gov (United States)

    C. N. Koller; L. S. Bauer; R. M. Hollingworth

    1992-01-01

    Native crystals of Bacillus thuringiensis var. san diego, a coleopteran-specific δ-endotoxin, were metabolically labeled with [35S]methionine. Specific activity was 82,000 CPM/μg (2.44 Ci/mmol). Using a universal buffer formulated with the same ionic strength at every pH, we determined that...

  6. Bacillus thuringiensis Cry3Aa protoxin intoxication of Tenebrio molitor induces widespread changes in the expression of serine peptidase transcripts

    Science.gov (United States)

    The yellow mealworm, Tenebrio molitor, is a pest of stored grain products and is sensitive to the coleopteran-specific Cry3Aa toxin from Bacillus thuringiensis (Bt). Larvae digest protein initially with cysteine peptidases in the anterior midgut and further with serine peptidases in middle and poste...

  7. Survival of Bacillus thuringiensis strains in gypsy moth (Lymantria dispar) larvae is correlated with production of urease

    Science.gov (United States)

    Phyllis A.W. Martin; Robert R. Jr. Farrar; Michael B. Blackburn

    2011-01-01

    We tested 50 lepidopteran-toxic Bacillus thuringiensis Berliner (Bt) strains with diverse phenotypes for the ability to survive repeated passages through larvae of the gypsy moth, Lymantria dispar (L.), without intervening growth on artificial media. These experiments have revealed a remarkable correlation...

  8. Isolation of transcripts from Diabrotica virgifera virgifera LeConte responsive to the Bacillus thuringiensis toxin Cry3Bb1

    Science.gov (United States)

    Crystal proteins derived from Bacillus thuringiensis (Bt) have been widely used as a method of insect pest management for several decades. In recent years, a transgenic corn expressing the Cry3Bb1 toxin has been successfully used for protection against corn rootworm larvae (Genus...

  9. Expression of Bacillus thuringiensis cytolytic toxin (Cyt2Ca1) in citrus roots to control Diaprepes abbreviatus larvae

    Science.gov (United States)

    Diaprepes abbreviatus (L.) is an important pest of citrus in the USA. Currently, no effective management strategies of Diaprepes abbreviatus exist in citriculture. To protect citrus against Diaprepes abbreviatus a transgenic citrus rootstock expressing Bacillus thuringiensis Cyt2Ca1, an insect toxin...

  10. Bacillus thuringiensis delta-endotoxin Cry1 hybrid proteins with increased activity against the Colorado potato beetle

    NARCIS (Netherlands)

    Naimov, S.; Weemen-Hendriks, M.; Dukiandjiev, S.; Maagd, de R.A.

    2001-01-01

    Cry1 delta-endotoxins of Bacillus thuringiensis are generally active against lepidopteran insects, but Cry1Ba and Cry1Ia have additional, though low, levels of activity against coleopterans such as the Colorado potato beetle. Here we report the construction of Cry1Ba/Cry1Ia hybrid toxins which have

  11. INSECTICIDAL TOXIN FROM BACILLUS THURINGIENSIS IS RELEASED FROM ROOTS OF TRANSGENIC BT CORN IN VITRO AND IN SITU. (R826107)

    Science.gov (United States)

    AbstractThe insecticidal toxin encoded by the cry1Ab gene from Bacillus thuringiensis was released in root exudates from transgenic Bt corn during 40 days of growth in soil amended to 0, 3, 6, 9, or 12% (v/v) with montmorillonite or kaolinite in a...

  12. The introduction of integrated pest management in the Ethiopian horticultural sector : Bacillus thuringiensis strains and its toxicity

    NARCIS (Netherlands)

    Belder, den E.; Elderson, J.

    2012-01-01

    1 Introduction As hazards of conventional broad acting pesticides are documented, researchers, poli cymakers and growers look for pesticides that are toxic only to the target pest, have no impact on other such as beneficial species, and have fewer environmental effects. Bacillus thuringiensis (Bt)

  13. Recovery of Bacillus thuringiensis and related spore-forming bacteria from soil after application for gypsy moth control

    Science.gov (United States)

    Phyllis A.W. Martin; Elizabeth A. Mongeon; Michael B. Blackburn; Dawn E. Gundersen-Rindal

    2011-01-01

    Bacillus thuringiensis Berliner (Bt) has been applied for gypsy moth (Lymantria dispar L.) control in forests in the northeastern U.S. for many years. The subspecies of Bt that is used (urstaki) is not common in U.S. soil. We attempted to recover Bt from...

  14. Characterization of eight Bacillus thuringiensis isolates originated from fecal samples of Fuzhou Zoo and Fuzhou Panda Center

    Czech Academy of Sciences Publication Activity Database

    Wu, Ch.; Wu, L.; Zhang, L.; Gelbič, Ivan; Xu, L.; Guan, X.

    2014-01-01

    Roč. 17, č. 3 (2014), s. 395-397 ISSN 1226-8615 Institutional support: RVO:60077344 Keywords : Bacillus thuringiensis * faeces * microscophy Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection Impact factor: 0.946, year: 2014 http://www.sciencedirect.com/science/article/pii/S122686151400034X

  15. Isolation and characterization of a novel native Bacillus thuringiensis strain BRC-HZM2 capable of degrading chlorpyrifos

    Czech Academy of Sciences Publication Activity Database

    Wu, S.; Peng, Y.; Huang, Z.; Huang, Z.; Xu, L.; Gelbič, Ivan; Guan, X.; Zhang, L.; Zou, S.

    2015-01-01

    Roč. 55, č. 3 (2015), s. 389-397 ISSN 0233-111X Institutional support: RVO:60077344 Keywords : Bacillus thuringiensis * biopesticide * biodegradation Subject RIV: EE - Microbiology, Virology Impact factor: 1.585, year: 2015 http://onlinelibrary.wiley.com/doi/10.1002/jobm.201300501/epdf

  16. Localization of Bacillus thuringiensis Cry1A toxin-binding molecules in gypsy moth larval gut sections using fluorescence microscopy

    Science.gov (United States)

    Algimantas P. Valaitis

    2011-01-01

    The microbial insecticide Bacillus thuringiensis (Bt) produces Cry toxins, proteins that bind to the brush border membranes of gut epithelial cells of insects that ingest it, disrupting the integrity of the membranes, and leading to cell lysis and insect death. In gypsy moth, Lymantria dispar, two toxin-binding molecules for the...

  17. 77 FR 6471 - Bacillus thuringiensis Cry2Ae Protein in Cotton; Exemption from the Requirement of a Tolerance

    Science.gov (United States)

    2012-02-08

    ... requirement of a tolerance for residues of Bacillus thuringiensis Cry2Ae protein in or on the food and feed... transformation using plasmid pTEM12. This PIP provides event GHB119 cotton protection against feeding damage by... for event GHB119 is BCS-GH005-8. The cry2Ae gene was isolated from Bt subspecies dakota and its...

  18. PENGARUH KETINGGIAN HABITAT KELAPA (Cocos nucifera TERHADAP PENGEMBANGBIAKAN Bacillus thuringiensis H-14 DAN TOKSISITASNYA TERHADAP JENTIK (Anopheles aconitus

    Directory of Open Access Journals (Sweden)

    Lulus Susanti

    2013-05-01

    Full Text Available Abstrak Penggunaan Bacillus thuringiensis H-14 sebagai biolarvasida sudah banyak diketahui di masyarakat. Balai Besar Penelitian dan Pengembangan Vektor dan Reservoir Penyakit (B2P2VRP telah menguji penggunaan media buah kelapa sebagai media pengembangbiakan B.thuringiensis H-14. Pada penelitian ini dilakukan pengembangbiakkan B.thuringiensis H-14 galur lokal dengan menggunakan media air kelapa yang diambil dari berbagai wilayah dengan memperhatikan ketinggian wilayahnya. Lokasi pengambilan sampel air kelapa adalah daerah dengan ketinggian < 20 m dpl (pantai Parangtritis, 21 – 250 m dpl (Kabupaten Purworejo, 251 – 500 m dpl (Kabupaten Semarang dan 501 – 750 m dpl (Kota Salatiga. Penelitian ini dilakukan dengan mengambil air buah kelapa hijau umur 4 – 6 bulan atau berat mencapai > 600 gram dari masing-masing wilayah penelitian. Kemudian air kelapa dari masing-masing wilayah penelitian diambil secara random untuk dilakukan pengujian kandungan nutrisinya, sedangkan sisanya di sterilisasi untuk dijadikan media pengembangbiakan B.thuringiensis H-14. Tujuan dari penelitian ini untuk mengetahui ada atau tidaknya perbedaan hasil pengembangbiakan di media air kelapa yang didapatkan dari lokasi dengan ketinggian habitat yang berbeda-beda, serta efek toksisitasnya terhadap jentik Anopheles aconitus. Hasil uji analisa air kelapa dari pantai Parangtritis adalah kadar karbohidrat 1,82%, dengan lemak 0,02%, protein 0,04% dan gula reduksi sebesar 1,67%. Air kelapa dari kabupaten Purworejo kandungan karbohidrat 1,92%, lemak 0,01%. protein 0,06% dan gula reduksi 1,87%. Air kelapa dari Kabupaten Semarang kandungan karbohidrat 1,68%, lemak 0,01%, protein 0,12% dan gula reduksi 1,52%. Sedangkan kandungan karbohidrat dari air kelapa kota Salatiga adalah 3,12% merupakan kandungan yang tertinggi dibandingkan dari daerah lain, kandungan lemak 0,01%, protein 0,11% dan gula reduksi 2,97%, merupakan kandungan tertinggi dibandingkan dengan hasil dari daerah lain

  19. Larvicidal efficacy of Catharanthus roseus Linn. (Family: Apocynaceae) leaf extract and bacterial insecticide Bacillus thuringiensis against Anopheles stephensi Liston.

    Science.gov (United States)

    Panneerselvam, Chellasamy; Murugan, Kadarkarai; Kovendan, Kalimuthu; Kumar, Palanisamy Mahesh; Ponarulselvam, Sekar; Amerasan, Duraisamy; Subramaniam, Jayapal; Hwang, Jiang-Shiou

    2013-11-01

    To explore the larvicidal activity of Catharanthus roseus (C. roseus) leaf extract and Bacillus thuringiensis (B. thuringiensis) against the malarial vector Anopheles stephensi (An. stephensi), when being used alone or together. The larvicidal activity was assayed at various concentrations under the laboratory and field conditions. The LC50 and LC90 values of the C. roseus leaf extract were determined by probit analysis. The plant extract showed larvicidal effects after 24 h of exposure; however, the highest larval mortality was found in the petroleum ether extract of C. roseus against the first to fourth instars larvae with LC50=3.34, 4.48, 5.90 and 8.17 g/L, respectively; B. thuringiensis against the first to fourth instars larvae with LC50=1.72, 1.93, 2.17 and 2.42 g/L, respectively; and the combined treatment with LC50=2.18, 2.41, 2.76 and 3.22 g/L, respectively. No mortality was observed in the control. The petroleum ether extract of C. roseus extract and B. thuringiensis have potential to be used as ideal eco-friendly agents for the control of An. stephensi in vector control programs. The combined treatment with this plant crude extract and bacterial toxin has better larvicidal efficacy against An. stephensi. Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  20. Nontarget impact of Bacillus thuringiensis kurstaki in central Appalachian mixed broadleaf-pine forests: long-term evaluation of arthropods

    Science.gov (United States)

    John S. Strazanac; George E. Seidel; Vicki Kondo; Cynthia J. Fritzler; Linda Butler

    2007-01-01

    Current measures for gypsy moth (Lymantria dispar L.) control emphasize the use of pheromones, growth regulators, and biopesticides. One of the biopesticides, Bacillus thuringiensis kurstaki (Btk), will continue to be necessary for immediate control of gypsy moth and other forest lepidopteran outbreaks. Although...

  1. Effect of proteolytic and detoxification enzyme inhibitors on Bacillus thuringiensis var. israelensis tolerance in the mosquito Aedes aegypti

    Czech Academy of Sciences Publication Activity Database

    Hu, X.; Guo, Y.; Wu, S.; Liu, Z.; Fu, T.; Shao, E.; Carballar-Lejarazú, R.; Zhao, G.; Huang, Z.; Gelbič, Ivan; Guan, X.; Zou, S.; Xu, L.; Zhang, L.

    2017-01-01

    Roč. 27, č. 2 (2017), s. 169-179 ISSN 0958-3157 Institutional support: RVO:60077344 Keywords : Bacillus thuringiensis * Bti * Aedes aegypti Subject RIV: ED - Physiology OBOR OECD: Biology (theoretical, mathematical, thermal, cryobiology, biological rhythm), Evolutionary biology Impact factor: 0.919, year: 2016

  2. [Bacillus thuringiensis: general aspects. An approach to its use in the biological control of lepidopteran insects behaving as agricultural pests].

    Science.gov (United States)

    Sauka, Diego H; Benintende, Graciela B

    2008-01-01

    Bacillus thuringiensis is the most widely applied biological pesticide used to control insects that affect agriculture and forestry and which transmit human and animal pathogens. During the past decades B. thuringiensis has been the subject of intensive research. These efforts have yielded considerable data about the relationships between the structure, mechanism of action, and genetics of their pesticidal crystal proteins. As a result, a coherent picture of these relationships has emerged. Other studies have focused on the ecological role of the B. thuringiensis crystal proteins and their performance in agricultural and other natural settings. With this knowledge as background and the help of biotechnological tools, researchers are now reporting promising results in the development of more useful toxins, recombinant bacteria, new formulations and transgenic plants that express pesticidal activity, in order to assure that these products are utilized with the best efficiency and benefit. This article is an attempt to integrate all these recent developments in the study of B. thuringiensis into a context of biological control of lepidopteran insect pest of agricultural importance.

  3. Beetle-specific Bacillus thuringiensis Cry3Aa toxin reduces larval growth and curbs reproduction in Spodoptera littoralis (Boisd.)

    Czech Academy of Sciences Publication Activity Database

    Hussein, Hany; Habuštová, Oxana; Sehnal, František

    2005-01-01

    Roč. 61, - (2005), s. 1186-1192 ISSN 1526-498X R&D Projects: GA ČR(CZ) GA522/02/1507 Institutional research plan: CEZ:AV0Z50070508 Keywords : Bacillus thuringiensis * Spodoptera littoralis * Bt applications Subject RIV: ED - Physiology Impact factor: 1.175, year: 2005

  4. Decolorization of dyehouse effluent and biodegradation of Congo red by Bacillus thuringiensis RUN1.

    Science.gov (United States)

    Olukanni, Olumide David; Osuntoki, Akinniyi A; Awotula, Ayodeji Olushola; Kalyani, Dayanand C; Gbenle, George Olabode; Govindwar, Sanjay P

    2013-06-28

    A dye-decolorizing bacterium was isolated from a soil sample and identified as Bacillus thuringiensis using 16S rRNA sequencing. The bacterium was able to decolorize three different textile dyes, namely, Reactive blue 13, Reactive red 58, and Reactive yellow 42, and a real dyehouse effluent up to 80-95% within 6 h. Some non-textile industrially important dyes were also decolorized to different extents. Fourier transform infrared spectroscopy and gas chromatography-mass spectrometer analysis of the ethyl acetate extract of Congo red dye and its metabolites showed that the bacterium could degrade it by the asymmetric cleavage of the azo bonds to yield sodium (4- amino-3-diazenylnaphthalene-1-sulfonate) and phenylbenzene. Sodium (4-amino-3-diazenylnaphthalene-1-sulfonate) was further oxidized by the ortho-cleavage pathway to yield 2- (1-amino-2-diazenyl-2-formylvinyl) benzoic acid. There was induction of the activities of laccase and azoreductase during the decolorization of Congo red, which suggests their probable role in the biodegradation. B. thuringiensis was found to be versatile and could be used for industrial effluent biodegradation.

  5. Isolation and toxicity test of Bacillus thuringiensis from Sekayu region soil, South Sumatra on Spodopteralitura

    Science.gov (United States)

    Afriani, S. R.; Pujiastuti, Y.; Irsan, C.; Damiri, N.; Nugraha, S.; Sembiring, E. R.

    2018-01-01

    This study aimed to obtain bacterial isolates B. thuringiensis potential as a biological control against pests Spodoptera litura. The research was conducted at the Laboratory of Pest and Disease Department, Agricultural Faculty of Sriwijaya University, Campus Inderalaya Ogan Ilir, South Sumatera, from March to June 2017. The study was conducted with survey method and laboratory trial. The results showed that of the 50 soil samples from three villages selected through morphological observation, reaction staining, KOH test, catalase test, producing 13 bacterial isolates. Screening of the 13th toxicity of the isolates suspected B. thuringiensis against S. litura larvae was investigated. Based on the toxicity screening test the following facts were obtained: five isolates ie KJ2M2, KJ3E1, KJ3JB1, KJ3D3 and KJ3D5 were lower toxicity than Dipel, two isolates ie KJ3K4 and KJ3D3 which had the same toxicity to Dipel. Five isolates the KJ3E3, KJ3BW5, KJ3JB5, KJ3D1 and LC2, LC3 known to have effectiveness until the seventh day reached 40%. There was one isolate that is KJ3BW5 which was more effective compared to Dipel as comparison.

  6. Isolation and characterization of radioresistant mutants in Bacillus subtilis and Bacillus thuringiensis

    International Nuclear Information System (INIS)

    Kalinin, V.L.; Petrov, V.N.; Petrova, T.M.

    1981-01-01

    Vegetative cells of Bac. thuringiensis var. galleriae (the wild-type strain 351) are much more sensitive to lethal effects of UV light and 60 Co-γ-rays than those of Bac. subtilis (the wild-type strain 168). This difference is less pronounced for spores of these strains. By means of repeated γ-irradiation-regrowth cycles radioresistant mutants Bac. thuringiensis Gamsup(r) 14 and Bac. subtilis Gamsup(r) 9 were selected. The vegetative cells of these mutants are correspondingly 19 times and 3.9 times more resistant to lethal effects of γ-radiation than the cells of the parental strains. The resistance of the Gamsup(r) mutant cells to lethal effects of UV light and H 2 O 2 is also increased. The spores of the Gamsup(r) 14 mutant are 1.5-1.7 times more resistant to γ-radiation and UV light than the wild-type spores. The radioresistant mutants and the parental strains do not vary in their capacity for host-cell reactivation of UV- or γ-irradiated phages Tg13 and 105

  7. High instability of a nematicidal Cry toxin plasmid in Bacillus thuringiensis.

    Science.gov (United States)

    Sheppard, Anna E; Nakad, Rania; Saebelfeld, Manja; Masche, Anna C; Dierking, Katja; Schulenburg, Hinrich

    2016-01-01

    In bacterial pathogens, virulence factors are often carried on plasmids and other mobile genetic elements, and as such, plasmid evolution is central in understanding pathogenicity. Bacillus thuringiensis is an invertebrate pathogen that uses plasmid-encoded crystal (Cry) toxins to establish infections inside the host. Our study aimed to quantify stability of two Cry toxin-encoding plasmids, BTI_23p and BTI_16p, under standard laboratory culturing conditions. These two plasmids are part of the genome of the B. thuringiensis strain MYBT18679, which is of particular interest because of its high pathogenicity towards nematodes. One of the plasmids, BTI_23p, was found to be highly unstable, with substantial loss occurring within a single growth cycle. Nevertheless, longer term experimental evolution in the absence of a host revealed maintenance of the plasmid at low levels in the bacterial populations. BTI_23p encodes two nematicidal Cry toxins, Cry21Aa2 and Cry14Aa1. Consistent with previous findings, loss of the plasmid abolished pathogenicity towards the nematode Caenorhabditis elegans, which could be rescued by addition of Cry21Aa2-expressing Escherichia coli. These results implicate BTI_23p as a plasmid that is required for successful infection, yet unstable when present at high frequency in the population, consistent with the role of Cry toxins as public goods. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Cytotoxicity Analysis of Three Bacillus thuringiensis Subsp. israelensis δ-Endotoxins towards Insect and Mammalian Cells

    Science.gov (United States)

    Teixeira Corrêa, Roberto Franco; Ardisson-Araújo, Daniel Mendes Pereira; Monnerat, Rose Gomes; Ribeiro, Bergmann Morais

    2012-01-01

    Three members of the δ-endotoxin group of toxins expressed by Bacillus thuringiensis subsp. israelensis, Cyt2Ba, Cry4Aa and Cry11A, were individually expressed in recombinant acrystalliferous B. thuringiensis strains for in vitro evaluation of their toxic activities against insect and mammalian cell lines. Both Cry4Aa and Cry11A toxins, activated with either trypsin or Spodoptera frugiperda gastric juice (GJ), resulted in different cleavage patterns for the activated toxins as seen by SDS-PAGE. The GJ-processed proteins were not cytotoxic to insect cell cultures. On the other hand, the combination of the trypsin-activated Cry4Aa and Cry11A toxins yielded the highest levels of cytotoxicity to all insect cells tested. The combination of activated Cyt2Ba and Cry11A also showed higher toxic activity than that of toxins activated individually. When activated Cry4Aa, Cry11A and Cyt2Ba were used simultaneously in the same assay a decrease in toxic activity was observed in all insect cells tested. No toxic effect was observed for the trypsin-activated Cry toxins in mammalian cells, but activated Cyt2Ba was toxic to human breast cancer cells (MCF-7) when tested at 20 µg/mL. PMID:23029407

  9. Quantification of Bacillus thuringiensis Vip3Aa16 Entomopathogenic Toxin Using Its Hemolytic Activity.

    Science.gov (United States)

    Boukedi, Hanen; Ben Khedher, Saoussen; Ghribi, Dhouha; Dammak, Mariam; Tounsi, Slim; Abdelkefi-Mesrati, Lobna

    2017-05-01

    Vegetative insecticidal proteins produced by some Bacillus thuringiensis strains are specifically toxic to different agricultural pests such as the polyphagous Spodoptera and several other Lepidopteran insects, but one of the major problems found in the use of these biopesticides was the lack of an easy and credible method of quantification of such secreted toxins. Heterologous expression of B. thuringiensis Vip3Aa16 toxin was performed in Escherichia coli then the protein was purified by chromatography. Using blood agar as well as blood agar overlay (zymogram assay), we reported, for the first time, the capacity of Vip3Aa16 to induce hemolysis. The hemolytic activity of this protein was shown to be relatively stable after treatment at 40 °C and at a range of pH between 6.5 and 9. Moreover, a linear relationship was shown between hemolysis levels and Vip3Aa16 concentrations. The model established in the present study could quantify Vip3A toxin as a function of hemolytic activity and the assay proposed showed to be a simple and low-cost method to readily assess Vip3A toxins in liquid cultures and facilitate the use of this kind of bioinsecticides in pest management programs.

  10. Two distinct pathways lead Bacillus thuringiensis to commit to sporulation in biofilm.

    Science.gov (United States)

    Verplaetse, Emilie; Slamti, Leyla; Gohar, Michel; Lereclus, Didier

    2017-05-01

    The spore-forming bacterium Bacillus thuringiensis is an efficient biofilm producer, responsible for persistent contamination of industrial food processing systems. B. thuringiensis biofilms are highly heterogeneous bacterial structures in which three distinct cell types controlled by quorum sensing regulators were identified: PlcR-controlled virulent cells, NprR-dependent necrotrophic cells and cells committed to sporulation, a differentiation process controlled by Rap phosphatases and Spo0A-P. Interestingly, a cell lineage study revealed that, in LB medium or in insect larvae, only necrotrophic cells became spores. Here we analyzed cellular differentiation undertaken by cells growing in biofilm in a medium optimized for sporulation. No virulent cells were identified; surprisingly, two distinct routes could lead to differentiation as a spore in this growth condition: the NprR-dependent route, followed by the majority of cells, and the newly identified NprR-independent route, which is followed by 20% of sporulating cells. Copyright © 2016. Published by Elsevier Masson SAS.

  11. Functional analysis of the sporulation-specific diadenylate cyclase CdaS in Bacillus thuringiensis

    Science.gov (United States)

    Zheng, Cao; Ma, Yang; Wang, Xun; Xie, Yuqun; Ali, Maria K.; He, Jin

    2015-01-01

    Cyclic di-AMP (c-di-AMP) is a recently discovered bacterial secondary messenger molecule, which is associated with various physiological functions. In the genus Bacillus, the intracellular level and turnover of c-di-AMP are mainly regulated by three diadenylate cyclases (DACs), including DisA, CdaA and CdaS, and two c-di-AMP-specific phosphodiesterases (GdpP and PgpH). In this study, we demonstrated that CdaS protein from B. thuringiensis is a hexameric DAC protein that can convert ATP or ADP to c-di-AMP in vitro and the N-terminal YojJ domain is essential for the DAC activity. Based on the markerless gene knock-out method, we demonstrated that the transcription of cdaS was initiated by the sporulation-specific sigma factor σH and the deletion of cdaS significantly delayed sporulation and parasporal crystal formation. These findings contrast with similar experiments conducted using B. subtilis, wherein transcription of its cdaS was initiated by the sigma factor σG. Deletion of all the three DAC genes from a single strain was unsuccessful, suggesting that c-di-AMP is an indispensable molecule in B. thuringiensis. Phylogenetic analysis indicated increased diversity of CdaS in the B. cereus and B. subtilis Bacillus subgroups. In summary, this study identifies important aspects in the regulation of c-di-AMP in the genus Bacillus. PMID:26441857

  12. Susceptibility of Grapholita molesta (Busck, 1916) to formulations of Bacillus thuringiensis, individual toxins and their mixtures.

    Science.gov (United States)

    Ricietto, Ana Paula Scaramal; Gomis-Cebolla, Joaquín; Vilas-Bôas, Gislayne Trindade; Ferré, Juan

    2016-11-01

    The Oriental fruit moth, Grapholita molesta (Lepidoptera: Tortricidae), is a major pest of fruit trees worldwide, such as peach and apple. Bacillus thuringiensis has been shown to be an efficient alternative to synthetic insecticides in the control of many agricultural pests. The objective of this study was to evaluate the effectiveness of B. thuringiensis individual toxins and their mixtures for the control of G. molesta. Bioassays were performed with Cry1Aa, Cry1Ac, Cry1Ca, Vip3Aa, Vip3Af and Vip3Ca, as well as with the commercial products DiPel® and XenTari®. The most active proteins were Vip3Aa and Cry1Aa, with LC 50 values of 1.8 and 7.5ng/cm 2 , respectively. Vip3Ca was nontoxic to this insect species. Among the commercial products, DiPel® was slightly, but significantly, more toxic than XenTari®, with LC 50 values of 13 and 33ng commercial product/cm 2 , respectively. Since Vip3A and Cry1 proteins are expressed together in some insect-resistant crops, we evaluated possible synergistic or antagonistic interactions among them. The results showed moderate to high antagonism in the combinations of Vip3Aa with Cry1Aa and Cry1Ca. Copyright © 2016. Published by Elsevier Inc.

  13. Effects of Bacillus thuringiensis strains virulent to Varroa destructor on larvae and adults of Apis mellifera.

    Science.gov (United States)

    Alquisira-Ramírez, Eva Vianey; Peña-Chora, Guadalupe; Hernández-Velázquez, Víctor Manuel; Alvear-García, Andrés; Arenas-Sosa, Iván; Suarez-Rodríguez, Ramón

    2017-08-01

    The sublethal effects of two strains of Bacillus thuringiensis, which were virulent in vitro to Varroa destructor, were measured on Apis mellifera. The effects of five concentrations of total protein (1, 5, 25, 50 and 100μg/mL) from the EA3 and EA26.1 strains on larval and adult honey bees were evaluated for two and seven days under laboratory conditions. Based on the concentrations evaluated, total protein from the two strains did not affect the development of larvae, the syrup consumption, locomotor activity or proboscis extension response of adults. These same parameters were also tested for the effects of three concentrations (1, 10 and 15μg/kg) of cypermethrin as a positive control. Although no significant differences were observed after two days of treatment with cypermethrin, a dose-response relationship in syrup consumption and locomotor activity was observed. A significant reduction in the proboscis extension response of the bees treated with cypermethrin was also observed. Therefore, in contrast to cypermethrin, our results indicate that the EA3 and EA26.1 strains of B. thuringiensis can be used in beehives to control V. destructor and reduce the negative effects of this mite on colonies without adverse effects on the larvae and adults of A. mellifera. Additionally, the overuse of synthetic miticides, which produce both lethal and sublethal effects on bees, can be reduced. Copyright © 2017 Elsevier Inc. All rights reserved.

  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. Cytotoxicity analysis of three Bacillus thuringiensis subsp. israelensis δ-endotoxins towards insect and mammalian cells.

    Directory of Open Access Journals (Sweden)

    Roberto Franco Teixeira Corrêa

    Full Text Available Three members of the δ-endotoxin group of toxins expressed by Bacillus thuringiensis subsp. israelensis, Cyt2Ba, Cry4Aa and Cry11A, were individually expressed in recombinant acrystalliferous B. thuringiensis strains for in vitro evaluation of their toxic activities against insect and mammalian cell lines. Both Cry4Aa and Cry11A toxins, activated with either trypsin or Spodoptera frugiperda gastric juice (GJ, resulted in different cleavage patterns for the activated toxins as seen by SDS-PAGE. The GJ-processed proteins were not cytotoxic to insect cell cultures. On the other hand, the combination of the trypsin-activated Cry4Aa and Cry11A toxins yielded the highest levels of cytotoxicity to all insect cells tested. The combination of activated Cyt2Ba and Cry11A also showed higher toxic activity than that of toxins activated individually. When activated Cry4Aa, Cry11A and Cyt2Ba were used simultaneously in the same assay a decrease in toxic activity was observed in all insect cells tested. No toxic effect was observed for the trypsin-activated Cry toxins in mammalian cells, but activated Cyt2Ba was toxic to human breast cancer cells (MCF-7 when tested at 20 µg/mL.

  16. Insecticidal Activity of Bacillus thuringiensis Strains Isolated from Soil and Water

    Directory of Open Access Journals (Sweden)

    Edyta Konecka

    2012-01-01

    Full Text Available We attempted to search novel Bacillus thuringiensis strains that produce crystals with potential utility in plant protection and with higher activity than strains already used in biopesticide production. Seven B. thuringiensis soil and water isolates were used in the research. We predicted the toxicity of their crystals by cry gene identification employing PCR method. The isolate MPU B63 with interesting, according to us, genes content was used in evaluating its crystal toxicity against Cydia pomonella caterpillars. The strain MPU B63 was cultured from water sample and had cry1Ab, cry1B, and cry15 genes. The LC50 crystals of MPU B63 were compared to LC50 of commercial bioinsecticide Foray determined against C. pomonella (codling moth. The activity of MPU B63 inclusions against codling moth larvae was approximately 24-fold higher than that of Foray. The results are a promising introduction for further study evaluating the potential usefulness of isolate MPU B63 crystals in plant protection.

  17. Insecticidal Activity of Bacillus thuringiensis Strains Isolated from Soil and Water

    Science.gov (United States)

    Konecka, Edyta; Baranek, Jakub; Hrycak, Anita; Kaznowski, Adam

    2012-01-01

    We attempted to search novel Bacillus thuringiensis strains that produce crystals with potential utility in plant protection and with higher activity than strains already used in biopesticide production. Seven B. thuringiensis soil and water isolates were used in the research. We predicted the toxicity of their crystals by cry gene identification employing PCR method. The isolate MPU B63 with interesting, according to us, genes content was used in evaluating its crystal toxicity against Cydia pomonella caterpillars. The strain MPU B63 was cultured from water sample and had cry1Ab, cry1B, and cry15 genes. The LC50 crystals of MPU B63 were compared to LC50 of commercial bioinsecticide Foray determined against C. pomonella (codling moth). The activity of MPU B63 inclusions against codling moth larvae was approximately 24-fold higher than that of Foray. The results are a promising introduction for further study evaluating the potential usefulness of isolate MPU B63 crystals in plant protection. PMID:22666145

  18. Adaptive Strategies of Bacillus thuringiensis Isolated from Acid Mine Drainage Site in Sabah, Malaysia.

    Science.gov (United States)

    Yik, Low Yi; Chin, Grace Joy Wei Lie; Budiman, Cahyo; Joseph, Collin Glenn; Musta, Baba; Rodrigues, Kenneth Francis

    2018-06-01

    The adaptive process in bacteria is driven by specific genetic elements which regulate phenotypic characteristics such as tolerance to high metal ion concentrations and the secretion of protective biofilms. Extreme environments such as those associated with heavy metal pollution and extremes of acidity offer opportunities to study the adaptive mechanisms of microorganisms. This study focused on the genome analysis of Bacillus thuringiensis (Bt MCMY1), a gram positive rod shaped bacterium isolated from an acid mine drainage site in Sabah, Malaysia by using a combination of Single Molecule Real Time DNA Sequencing, Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). The genome size of Bt MCMY1 was determined to be 5,458,152 bases which was encoded on a single chromosome. Analysis of the genome revealed genes associated with resistance to Copper, Mercury, Arsenic, Cobalt, Zinc, Cadmium and Aluminum. Evidence from SEM and FTIR indicated that the bacterial colonies form distinct films which bear the signature of polyhydroxyalkanoates (PHA) and this finding was supported by the genome data indicating the presence of a genetic pathway associated with the biosynthesis of PHAs. This is the first report of a Bacillus sp. isolated from an acid mine drainage site in Sabah, Malaysia and the genome sequence will provide insights into the manner in which B. thuringiensis adapts to acid mine drainage.

  19. Analysis of abrB Expression during the Infectious Cycle of Bacillus thuringiensis Reveals Population Heterogeneity

    Directory of Open Access Journals (Sweden)

    Samia Ben Rejeb

    2017-12-01

    Full Text Available Using the model host/pathogen pair Galleria mellonella/Bacillus thuringiensis, we have shown that these bacteria could kill their insect host, survive in its cadaver and form spores by sequentially activating virulence, necrotrophism and sporulation genes. However, the population isolated from the cadavers was heterogeneous, including non-sporulating cells in an unknown physiological state. To characterize these bacteria, we used a transcriptional fusion between the promoter of a gene expressed during early exponential growth (abrB and a reporter gene encoding a destabilized version of GFP, in combination with a fluorescent reporter of the necrotrophic state. The composition of the bacterial population during infection was then analyzed by flow cytometry. We showed that the PabrB promoter was activated in the population that had turned on the necrotrophic reporter, suggesting a re-entry into vegetative growth. Strikingly, the cells that did not go through the necrotrophic state did not activate the PabrB promoter and appear as a dormant subpopulation. We propose a new model describing the B. thuringiensis cell types during infection.

  20. Fate of insecticidal Bacillus thuringiensis Cry protein in soil: differences between purified toxin and biopesticide formulation.

    Science.gov (United States)

    Hung, Truong Phuc; Truong, Le Van; Binh, Ngo Dinh; Frutos, Roger; Quiquampoix, Hervé; Staunton, Siobhán

    2016-12-01

    Bacillus thuringiensis produces insecticidal proteins known as Cry, and its efficiency and absence of side effects make it the most widely used biopesticide. There is little information on the role of soils in the fate of Cry proteins from commercial biopesticide formulations, unlike toxins from genetically modified crops, which have been intensively studied in recent years. The persistence of Cry in soil was followed under field and laboratory conditions. Sunlight accelerated loss of detectable Cry under laboratory conditions, but little effect of shade was observed under field conditions. The half-life of biopesticide proteins in soil under natural conditions was about 1 week. Strong temperature effects were observed, but they differed for biopesticide and purified protein, indicating different limiting steps. For the biopesticide, the observed decline in detectable protein was due to biological factors, possibly including the germination of B. thuringiensis spores, and was favoured by higher temperature. In contrast, for purified proteins, the decline in detectable protein was slower at low temperature, probably because the conformational changes of the soil-adsorbed protein, which cause fixation and hence reduced extraction efficiency, are temperature dependent. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  1. Bacillus thuringiensis strain NG, a Novel Isolated Strain for production of Various Polyhydroxyalkanoates

    Directory of Open Access Journals (Sweden)

    Nazila Gholamveisi

    2017-12-01

    Full Text Available Introduction: Microbial biopolymers such as polyhydroxyalkanoates (PHA are proper alternatives for petroleum-derived plastics. These biopolymers have many advantages over conventional plastics such as biodegradability, environmental friendly and infinite as a renewable resource. Therefore, our study was aimed to isolate a bacterial strain capable of producing polyhydroxybutyrate (PHB; a highly applicable type of PHA. Materials and methods: To this aim, a total of 6 PHA-producing bacteria were isolated from waste water exit site of a brewery factory. The 6 isolates were studied by Sudan black-staining technique and the most stained isolate was selected for further studies. Next, the selected isolate was identified based on morphological, biochemical and phylogenetic analyses. Finally, the ability of strain in producing PHB as well as other PHAs was analyzed via GC-MS technique. Results: Strain NG had the highest yield of PHB, according to Sudan black-staining technique and it was selected for further studies. The strain NG was identified as a new strain of Bacillus thuringiensis. According to GC-MS results, this strain was able to produce PHB as well as 4 other PHAs including hexadecanoic acid methyl ester, octadecanoic acid methyl ester, tetradecanoic acid methyl ester, 8-octadecenoic acid methyl ester. Discussion and conclusion: It was the first report on producing various PHAs at the same time by a strain of Bacillus thuringiensis.

  2. Isolation, characterization and toxicity of native Bacillus thuringiensis isolates from different hosts and habitats in Iran

    Directory of Open Access Journals (Sweden)

    Ghassemi-Kahrizeh Akbar

    2017-09-01

    Full Text Available Bacillus thuringiensis is a Gram-positive, aerobic, facultative anaerobic and endospore-forming bacterium. Different strains of this species have the ability to produce parasporal crystalline inclusions which are toxic to larvae of different insect orders and other invertebrates and cause rapid death of the host. To determine the importance of this species in microbial control, we collected native strains and studied their virulence on the diamondback moth, Plutella xylostella. More than 148 samples were collected from Alborz, Guilan and Mazandaran Provinces. Experimental samples, including soil samples from forests, fruit gardens, agricultural fields, diseased and dead larvae, were transferred to a laboratory in sterile plastic containers. For evaluating B. thuringiensis isolates virulence, a cabbage leaf dip method with 106 cell · ml−1 concentration of various Bt isolates was applied to diamondback moths. Larval mortality was recorded 72 h after treatment. Based on bioassay results, all isolates were classified into three high, medium and low virulence groups. Protein level characterization based on the SDS-PAGE gel analysis showed that two isolates from a high virulence group have proteins of high molecular masses of 121 and 109 kDa. Results revealed that there is a positive correlation between protein masses and virulence of isolates. In addition, this research introduced nine strains that are highly toxic to P. xylostella and would be valuable as insecticidal agents for controlling lepidopteran pests.

  3. Probiotic Enterococcus mundtii Isolate Protects the Model Insect Tribolium castaneum against Bacillus thuringiensis

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    Thorben Grau

    2017-07-01

    Full Text Available Enterococcus mundtii strains isolated from the larval feces of the Mediterranean flour moth Ephestia kuehniella show antimicrobial activity against a broad spectrum of Gram-positive and Gram-negative bacteria. The in vitro probiotic characterization of one isolate revealed a high auto-aggregation score, a hydrophilic cell surface, tolerance for low pH, no hemolytic activity, and susceptibility to all tested antibiotics. We used the red flour beetle Tribolium castaneum, an established model organism, for the in vivo characterization of one probiotic E. mundtii isolate from E. kuehniella larvae. Tribolium castaneum larvae were fed orally with the probiotic isolate or the corresponding supernatant and then infected with either the entomopathogen Bacillus thuringiensis or Pseudomonas entomophila. Larvae exposed to the isolate or the supernatant showed increased survival following infection with B. thuringiensis but not P. entomophila. Heat treatment or treatment with proteinase K reduced the probiotic effect of the supernatant. However, the increased resistance attracts a fitness penalty manifested as a shorter lifespan and reduced fertility. T. castaneum has, pending on further research, the potential as an alternative model for the pre-screening of probiotics.

  4. Characterization of a Chitin-Binding Protein from Bacillus thuringiensis HD-1.

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    Naresh Arora

    Full Text Available Strains of Bacillus thuringiensis produce insecticidal proteins. These strains have been isolated from diverse ecological niches, such as soil, phylloplane, insect cadavers and grain dust. To effectively propagate, these strains produce a range of molecules that facilitate its multiplication in a competing environment. In this report, we have examined synthesis of a chitin-binding protein and evaluated its effect on fungi encountered in environment and its interaction with insecticidal proteins synthesized by B. thuringiensis. The gene encoding chitin-binding protein has been cloned and expressed. The purified protein has been demonstrated to interact with Cry insecticidal protein, Cry1Ac by Circular Dichrosim spectroscopy (CD and in vitro pull down assays. The chitin-binding protein potentiates insecticidal activity of bacillar insecticidal protein, Cry1Ac. Further, chitin-binding protein was fungistatic against several soil fungi. The chitin binding protein is expressed in spore mother cell and deposited along with insecticidal protein, Cry1Ac. It interacts with Cry1Ac to potentiate its insecticidal activity and facilitate propagation of Bacillus strain in environment by inhibiting growth of certain fungi.

  5. Optimization of process parameters for enhanced biodegradation of acid red 119 by Bacillus thuringiensis SRDD

    Directory of Open Access Journals (Sweden)

    Riddhi H. Dave

    2012-02-01

    Full Text Available Developed Bacillus thuringiensis SRDD showed degradation of C.I. Acid red 119 and growth under the extremecondition of temperature 70°C, pH 3-8, heavy metals concentration of 0.8 mM, NaCl up to 900 mM and 1000 ppm dye. Cottonseed, caster cake and corn cake powders were found to be better and cheaper nutrient supplements for the Bacillus thuringiensisSRDD for biodegradation as compared to molasses. After development of the culture and the process, more than99% degradation was achieved in less than 2 hrs of contact time even on 18th cycles of addition of 100 ppm AR-119 dye. Thedeveloped process showed AR-119 biodegradation rate as high as 220 mg L-1 h-1, which is found to be 130 times more ascompared to the reported data. U.V., FTIR, TLC and HPLC analysis data confirmed biodegradation ability of the Bacillusthuringiensis for AR-119.

  6. Characterization of a Chitin-Binding Protein from Bacillus thuringiensis HD-1.

    Science.gov (United States)

    Arora, Naresh; Sachdev, Bindiya; Gupta, Rani; Vimala, Y; Bhatnagar, Raj K

    2013-01-01

    Strains of Bacillus thuringiensis produce insecticidal proteins. These strains have been isolated from diverse ecological niches, such as soil, phylloplane, insect cadavers and grain dust. To effectively propagate, these strains produce a range of molecules that facilitate its multiplication in a competing environment. In this report, we have examined synthesis of a chitin-binding protein and evaluated its effect on fungi encountered in environment and its interaction with insecticidal proteins synthesized by B. thuringiensis. The gene encoding chitin-binding protein has been cloned and expressed. The purified protein has been demonstrated to interact with Cry insecticidal protein, Cry1Ac by Circular Dichrosim spectroscopy (CD) and in vitro pull down assays. The chitin-binding protein potentiates insecticidal activity of bacillar insecticidal protein, Cry1Ac. Further, chitin-binding protein was fungistatic against several soil fungi. The chitin binding protein is expressed in spore mother cell and deposited along with insecticidal protein, Cry1Ac. It interacts with Cry1Ac to potentiate its insecticidal activity and facilitate propagation of Bacillus strain in environment by inhibiting growth of certain fungi.

  7. Characterization of a Chitin-Binding Protein from Bacillus thuringiensis HD-1

    Science.gov (United States)

    Gupta, Rani; Vimala, Y.; Bhatnagar, Raj K.

    2013-01-01

    Strains of Bacillus thuringiensis produce insecticidal proteins. These strains have been isolated from diverse ecological niches, such as soil, phylloplane, insect cadavers and grain dust. To effectively propagate, these strains produce a range of molecules that facilitate its multiplication in a competing environment. In this report, we have examined synthesis of a chitin-binding protein and evaluated its effect on fungi encountered in environment and its interaction with insecticidal proteins synthesized by B. thuringiensis. The gene encoding chitin-binding protein has been cloned and expressed. The purified protein has been demonstrated to interact with Cry insecticidal protein, Cry1Ac by Circular Dichrosim spectroscopy (CD) and in vitro pull down assays. The chitin-binding protein potentiates insecticidal activity of bacillar insecticidal protein, Cry1Ac. Further, chitin-binding protein was fungistatic against several soil fungi. The chitin binding protein is expressed in spore mother cell and deposited along with insecticidal protein, Cry1Ac. It interacts with Cry1Ac to potentiate its insecticidal activity and facilitate propagation of Bacillus strain in environment by inhibiting growth of certain fungi. PMID:23824872

  8. Novel toxicity of Bacillus thuringiensis strains against the melon fruit fly, Bactrocera cucurbitae (Diptera: Tephritidae).

    Science.gov (United States)

    Shishir, Md Asaduzzaman; Akter, Asma; Bodiuzzaman, Md; Hossain, M Aftab; Alam, Md Musfiqul; Khan, Shakil Ahmed; Khan, Shakila Nargis; Hoq, M Mozammel

    2015-01-01

    Bactrocera cucurbitae (melon fruit fly) is one of the most detrimental vegetable-damaging pests in Bangladesh. The toxicity of Bacillus thuringiensis (Bt) has been reported against a few genera of Bactrocera in addition to numerous other insect species. Bt strains, harbouring cry1A-type genes were, therefore, assayed in vivo against the 3(rd) instar larvae of B. cucurbitae in this study. The biotype-based prevalence of cry1 and cry1A genes was calculated to be 30.8% and 11.16%, respectively, of the test strains (n=224) while their prevalence was greatest in biotype kurstaki. Though three indigenous Bt strains from biotype kurstaki with close genetic relationship exhibited higher toxicity, maximum mortalities were recorded for Btk HD-73 (96%) and the indigenous Bt JSc1 (93%). LC50 and LC99 values were determined to be 6.81 and 8.32 for Bt JSc1, 7.30 and 7.92 for Bt SSc2, and 6.99 and 7.67 for Btk HD-73, respectively. The cause of toxicity and its variation among the strains was found to be correlated with the synergistic toxic effects of cry1, cry2, cry3 and cry9 gene products, i.e. relevant Cry proteins. The novel toxicity of the B. thuringiensis strains against B. cucurbitae revealed in the present study thus will help in developing efficient and eco-friendly control measures such as Bt biopesticides and transgenic Bt cucurbits.

  9. Uso de productos derivados de Bacillus thuringiensis como alternativa de control en nematodos de importancia veterinaria. Revisión

    Directory of Open Access Journals (Sweden)

    Alejandro Vázquez-Pineda

    2012-01-01

    Full Text Available La bacteria entomopatógena Bacillus thuringiensis produce cristales proteicos con actividad citotóxica en contra de insectos y nematodos. La toxicidad de B. thuringiensis en plagas agrícolas es ampliamente conocida, pero poco se conoce acerca de su actividad en contra de nematodos parásitos. Recientemente, la actividad nematicida de las proteínas derivadas de B. thuringiensis se demostró en parásitos de mamíferos como Haemonchus, Teladorsagia, Nippostrongylus, y Ancylostoma, y en nematodos de plantas, Globodera y Meloidogyne. Entre el grupo de B. thuringiensis con efecto nematicida, las proteínas de la cepa IB-16 han mostrado actividad letal de 50 a 100 % en contra de diferentes estadios del principal género de rumiantes, Haemonchus contortus. Asimismo, los géneros de nematodos de vida libre, Panagrellus redivivus y Caenorhabditis elegans han sido blanco de estudios de la acción nematicida de B. thuringiensis. Por ejemplo, el efecto tóxico de la proteína Cry5B de B. thuringiensis se observó en las células intestinales de C. elegans, además esta acción parece involucrar receptores celulares específicos, similares a los que se han notificado en contra de plagas agrícolas. Asimismo, la unión de la proteína Cry5B ocurre en receptores específicos, como moléculas de carbohidratos, las cuales están presentes en la membrana de las células de intestino de los nematodos, ocasionando daño y muerte. A través de este tipo de estudios, los derivados de B. thuringiensis podrían considerarse una alternativa de control en nematodos que afectan a los animales domésticos, como rumiantes, así como en contra de otros nematodos patógenos de mamíferos e incluso de plantas agrícolas.

  10. Salmonella enterica serovar Typhimurium DT104 invasion is not enhanced by sub-inhibitory concentrations of the antibiotic florfenicol

    Science.gov (United States)

    The incidence of multi-drug resistant Salmonella has increased globally over the past several decades. Isolates of Salmonella enterica serovar Typhimurium DT104 are resistant to five or more antibiotics, including florfenicol, and have been associated with enhanced virulence in livestock and humans....

  11. Role of anionic charges of osmoregulated periplasmic glucans of Salmonella enterica Serovar Typhimurium SL1344 in mice virulence

    Science.gov (United States)

    Osmoregulated periplasmic glucans (OPGs) are important periplasmic constituents of Salmonella spp. and are required for optimal growth in hypoosmotic environments such as irrigation and vegetable wash waters as well as for mice virulence. opgB gene of Salmonella enterica serovar Typhimurium was ide...

  12. Critical role of glycogen synthase kinase-3ß in regulating the avian heterophil response to Salmonella enterica serovar Enteritidis

    Science.gov (United States)

    A microarray-assisted gene expression screen of chicken heterophils revealed glycogen synthase kinase-3ß (GSK-3ß), a multifunctional Ser/Thr kinase, to be consistently up-regulated 30-180 min following stimulation with Salmonella enterica serovar Enteritidis (S. Enteritidis). The present study was ...

  13. Ecology and modelling of Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium in cattle manure and soil

    NARCIS (Netherlands)

    Semenov, A.V.

    2008-01-01

    The number of food poisoning cases caused by enteropathogens has increased in recent years. A significant part of the outbreaks associated with the consumption of raw vegetables has been attributed to Escherichia coli O157:H7 and Salmonella enterica subsp. enterica serovar Typhimurium. Bovine manure

  14. Quantification of contamination of lettuce by GFP-expressing Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium

    NARCIS (Netherlands)

    Franz, Eelco; Visser, Anna A; Van Diepeningen, Anne D; Klerks, Michel M; Termorshuizen, Aad J; van Bruggen, Ariena H C

    The primary objective of this study was to determine the possibility of internalization of GFP-expressing Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium (S. Typhimurium) strains MAE 110 (multi-cellular morphology) and 119 (wild type morphology) into lettuce seedlings (Lactuca

  15. Draft Genome Sequence of a Salmonella enterica Serovar Typhi Strain Resistant to Fourth-Generation Cephalosporin and Fluoroquinolone Antibiotics

    OpenAIRE

    Gul, Danish; Potter, Robert F.; Riaz, Hurmat; Ashraf, Shifa Tariq; Wallace, Meghan A.; Munir, Tehmina; Ali, Amjad; Burnham, Carey-Ann; Dantas, Gautam; Andleeb, Saadia

    2017-01-01

    ABSTRACT Typhoid is endemic in developing countries. We report here the first draft genome sequence of a Salmonella enterica serovar Typhi clinical isolate from Pakistan exhibiting resistance to cefepime (a fourth-generation cephalosporin) and fluoroquinolone antibiotics, two of the last-generation therapies against this pathogen. The genome is ~4.8 Mb, with two putative plasmids.

  16. Molecular identification of Salmonella enterica subsp. enterica serovar Gallinarum biovars Gallinarum and Pullorum by a duplex PCR assay.

    Science.gov (United States)

    Batista, Diego Felipe Alves; de Freitas Neto, Oliveiro Caetano; de Almeida, Adriana Maria; Barrow, Paul Andrew; de Oliveira Barbosa, Fernanda; Berchieri Junior, Angelo

    2016-07-01

    Salmonella enterica subsp. enterica serovar Gallinarum biovar Gallinarum (S Gallinarum) and biovar Pullorum (S Pullorum) are 2 poultry pathogens that cause major economic losses to the poultry industry worldwide. Control of both diseases mainly relies on the adoption of biosecurity programs, and success is dependent on accurate and fast detection. Based on this concept, we developed a duplex PCR assay, targeting 2 chromosomal sequences, which allowed us to precisely identify and differentiate S Gallinarum and S Pullorum field strains. This assay was validated by testing genomic DNA from 40 S Gallinarum and 29 S Pullorum field strains, 87 other Salmonella serovars, and 7 non-Salmonella strains. The serovar identifier region (SIR) primers produced a fragment only in S Gallinarum and S Pullorum strains, whereas the fragment from the ratA coding sequence, which was previously demonstrated to differentiate the 2 biovars, was also amplified from other Salmonella serovars. Our results showed that the combination of both SIR and ratA amplifications could be used to identify as well as to differentiate colonies of S Gallinarum and S Pullorum reliably. Thus, we believe this methodology can be a useful ancillary tool for routine veterinary diagnostic laboratories by providing rapid, accurate results. © 2016 The Author(s).

  17. A functional cra gene is required for Salmonella enterica serovar typhimurium virulence in BALB/c mice

    DEFF Research Database (Denmark)

    Allen, J. H.; Utley, M.; Van den Bosch, H.

    2000-01-01

    A minitransposon mutant of Salmonella enterica serovar Typhimurium SR-11, SR-11 Fad(-), is unable to utilize gluconeogenic substrates as carbon sources and is avirulent and immunogenic when administered perorally to BALB/c mice (M. J. Utley et al., FEMS Microbiol. Lett., 163:129-134, 1998). Here...

  18. Serological and molecular characterization of leptospira serovar Kenya from captive African giant pouched rats (Cricetomys gambianus) from Morogoro Tanzania

    NARCIS (Netherlands)

    Machang'u, R. S.; Mgode, G. F.; Assenga, J.; Mhamphi, G.; Weetjens, B.; Cox, C.; Verhagen, R.; Sondij, S.; Goris, M. G.; Hartskeerl, R. A.

    2004-01-01

    Two identical leptospiral isolates coded Sh9 and Sh25 obtained from the urine of captive African giant pouched rats (Cricetomys gambianus), destined for use as biodetector of antipersonnel landmines were typed as serovar Kenya using cross-agglutination absorption test and DNA fingerprinting with the

  19. Quantification of contamination of lettuce by GFP-expressing Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium

    NARCIS (Netherlands)

    Franz, E.; Visser, A.A.; Diepeningen, van A.D.; Klerks, M.M.; Termorshuizen, A.J.; Bruggen, van A.H.C.

    2007-01-01

    The primary objective of this study was to determine the possibility of internalization of GFP-expressing Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium (S. Typhimurium) strains MAE 110 (multi-cellular morphology) and 119 (wild type morphology) into lettuce seedlings (Lactuca

  20. Draft Genome Sequences of Four Salmonella enterica subsp. enterica Serovar Enteritidis Strains Implicated in Infections of Avian and Human Hosts

    KAUST Repository

    An, Ran

    2018-01-24

    Salmonella enterica subsp. enterica serovar Enteritidis is a wide-host-range pathogen. Occasionally, it is involved in invasive infections, leading to a high mortality rate. Here, we present the draft genome sequences of four S Enteritidis strains obtained from human and avian hosts that had been involved in bacteremia, gastroenteritis, and primary infections.

  1. Chlortetracycline and florfenicol induce expression of genes associated with pathogenicity in multidrug-resistant Salmonella enterica serovar Typhimurium

    Science.gov (United States)

    Background Multidrug-resistant (MDR) Salmonella enterica serovar Typhimurium (S. Typhimurium) is a serious public health threat as infections caused by these strains are more difficult and expensive to treat. Livestock serve as a reservoir for MDR Salmonella, and the antibiotics chlortetracycline an...

  2. Analysis of the contribution of bacteriophage ST64B to in vitro virulence traits of Salmonella enterica serovar Typhimurium

    DEFF Research Database (Denmark)

    Fresno, Ana Herrero; Leekitcharoenphon, Pimlapas; Hendriksen, Rene S.

    2014-01-01

    Comparison of the publicly available genomes of the virulent Salmonella enterica serovar Typhimurium (S. Typhimurium) strains SL1344, 14028s and D23580 to that of the virulence-attenuated isolate LT2 revealed the absence of a full sequence of bacteriophage ST64B in the latter. Four selected ST64B...

  3. Chromosomal rearrangements formed by rrn recombination do not improve replichore balance in host-specific Salmonella enterica serovars.

    Directory of Open Access Journals (Sweden)

    T David Matthews

    2010-10-01

    Full Text Available Most of the ∼2,600 serovars of Salmonella enterica have a broad host range as well as a conserved gene order. In contrast, some Salmonella serovars are host-specific and frequently exhibit large chromosomal rearrangements from recombination between rrn operons. One hypothesis explaining these rearrangements suggests that replichore imbalance introduced from horizontal transfer of pathogenicity islands and prophages drives chromosomal rearrangements in an attempt to improve balance.This hypothesis was directly tested by comparing the naturally-occurring chromosomal arrangement types to the theoretically possible arrangement types, and estimating their replichore balance using a calculator. In addition to previously characterized strains belonging to host-specific serovars, the arrangement types of 22 serovar Gallinarum strains was also determined. Only 48 out of 1,440 possible arrangement types were identified in 212 host-specific strains. While the replichores of most naturally-occurring arrangement types were well-balanced, most theoretical arrangement types had imbalanced replichores. Furthermore, the most common types of rearrangements did not change replichore balance.The results did not support the hypothesis that replichore imbalance causes these rearrangements, and suggest that the rearrangements could be explained by aspects of a host-specific lifestyle.

  4. Transcriptomic analysis of swarm motility phenotype of Salmonella enterica serovar Typhimurium mutant defective in periplasmic glucan synthesis

    Science.gov (United States)

    Movement of food-borne pathogens on moist surfaces enables them to migrate towards more favorable niches and facilitate their survival for extended periods of time. Salmonella enterica serovar Typhimurium mutants defective in OPG synthesis are unable to exhibit motility on moist surfaces (swarming) ...

  5. Construction of physical and genetic maps of Chlamydia trachomatis serovar L2 by pulsed-field gel electrophoresis

    DEFF Research Database (Denmark)

    Birkelund, Svend; Stephens, RS

    1992-01-01

    We constructed the physical map of Chlamydia trachomatis serovar L2 by using three restriction endonucleases, NotI (GC[GGCCGC), SgrAI (C(A/G)[CCGG(T/G)G), and Sse8387I (CCTGCA[GG), and we analyzed the fragments by pulsed-field gel electrophoresis. A total of 25 restriction endonuclease sites and 13...

  6. Draft Genome Sequence ofSalmonella entericasubsp.entericaSerovar Infantis Strain SPE101, Isolated from a Chronic Human Infection.

    Science.gov (United States)

    Iriarte, Andrés; Giner-Lamia, Joaquín; Silva, Claudia; Betancor, Laura; Astocondor, Lizeth; Cestero, Juan J; Ochoa, Theresa; García, Coralith; Puente, José L; Chabalgoity, José A; García-Del Portillo, Francisco

    2017-07-20

    We report a 4.99-Mb draft genome sequence of Salmonella enterica subsp. enterica serovar Infantis strain SPE101, isolated from feces of a 5-month-old breast-fed female showing diarrhea associated with severe dehydration and malnutrition. The infection prolonged for 6 months despite antibiotic treatment. Copyright © 2017 Iriarte et al.

  7. Alternate phase variation in expression of two major surface membrane proteins (MBA and UU376) of Ureaplasma parvum serovar 3.

    Science.gov (United States)

    Zimmerman, Carl-Ulrich R; Stiedl, Thomas; Rosengarten, Renate; Spergser, Joachim

    2009-03-01

    Ureaplasma urealyticum and Ureaplasma parvum are commensals and pathogens of the human urogenital tract and of newborn infants. There are four distinct U. parvum serovars and 10 distinct U. urealyticum serovars. Both species possess a distinct immunodominant variable surface protein, the multiple banded antigen (MBA), which shows size variability among isolates as a result of changes in the number of C-terminal repeating units. Adjacent to the MBA gene (UU375) lies UU376, which was annotated as 'Ureaplasma-specific conserved hypothetical gene'. In four different strains of U. parvum serovar 3, we demonstrated expression of UU376 by Western blot analysis and phase variation between UU376, here designated Upvmp376 (Ureaplasma phase-variable membrane protein 376), and MBA after application of selective pressure with hyperimmune antisera directed against either protein. By Southern blot analysis, we found that the switch between MBA and Upvmp376 expression is associated with a DNA inversion event in which the nonrepetitive region of the MBA gene and its putative promoter region are opposed to either the repetitive region of MBA or UU376. We propose that in U. parvum serovar 3, and presumably in all U. parvum and U. urealyticum, an inversion event at specific sites effects an alternate ON/OFF switching of the genes UU375 and UU376.

  8. A rapid and specific detection of pathogenic serovar Salmonella typhimurium by loop-mediated isothermal amplification method (LAMP

    Directory of Open Access Journals (Sweden)

    Hadi Ravan

    2017-09-01

    Discussion and conclusion: As a result of a high sensitivity and specificity of the method as well as its low cost per assay, it could be concluded that the present LAMP assay is a powerful, accurate, and efficient method for detecting pathogenic serovar Salmonella typhimurium in food-processing industries and diagnostic laboratories.

  9. Spore prevalence and toxigenicity of Bacillus cereus and Bacillus thuringiensis isolates from U.S. retail spices.

    Science.gov (United States)

    Hariram, Upasana; Labbé, Ronald

    2015-03-01

    Recent incidents of foodborne illness associated with spices as the vehicle of transmission prompted this examination of U.S. retail spices with regard to Bacillus cereus. This study focused on the levels of aerobic-mesophilic spore-forming bacteria and B cereus spores associated with 247 retail spices purchased from five states in the United States. Samples contained a wide range of aerobic-mesophilic bacterial spore counts ( 10(7) CFU/g). Using a novel chromogenic agar, B. cereus and B. thuringiensis spores were isolated from 77 (31%) and 11 (4%) samples, respectively. Levels of B. cereus were thuringiensis isolates possessed at least one type of enterotoxin gene: HBL (hemolysin BL) or nonhemolytic enterotoxin (NHE). None of the 88 isolates obtained in this study possessed the emetic toxin gene (ces). Using commercially available immunological toxin detection kits, the toxigenicity of the isolates was confirmed. The NHE enterotoxin was expressed in 98% of B. cereus and 91% of B. thuringiensis isolates that possessed the responsible gene. HBL enterotoxin was detected in 87% of B. cereus and 100% of B. thuringiensis PCR-positive isolates. Fifty-two percent of B. cereus and 54% of B. thuringiensis isolates produced both enterotoxins. Ninety-seven percent of B. cereus isolates grew at 12°C, although only two isolates grew well at 9°C. The ability of these spice isolates to form spores, produce diarrheal toxins, and grow at moderately abusive temperatures makes retail spices an important potential vehicle for foodborne illness caused by B. cereus strains, in particular those that produce diarrheal toxins.

  10. Characterization, N-terminal sequencing and classification of Tolworthcin 524: A bacteriocin produced by Bacillus thuringiensis subsp. tolworthi.

    Science.gov (United States)

    Pacheco-Cano, Rubén D; de la Fuente-Salcido, Norma M; Salcedo-Hernández, Rubén; León-Galván, M Fabiola; Bideshi, Dennis K; Hernández-Guzmán, Gustavo; Barboza-Corona, J Eleazar

    2014-12-01

    Bacteriocins synthesized by entomopathogenic Bacillus thuringiensis are gaining attention owing to their inhibitory effects against a wide variety of pathogenic bacteria. In the present study, we purified and characterized Tolworthcin 524, a bacteriocin synthesized by B. thuringiensis subsp. tolworthi, and compared it with other bacteriocins synthesized by B. thuringiensis. Tolworthcin 524 was separated and purified from the secretome of B. thuringiensis by fast protein liquid chromatography with a gel filtration column to obtain yields of 17% and a specific activity of ∼3600U/mgprotein. The purified product showed two peptides of ∼9 and 6kDa with antimicrobial activity in a gel-screening assay. The purified product was analyzed by two-dimensional electrophoresis and the resolved peptides of ∼9 and 6kDa with isoelectric points of ∼8 were sequenced. Partial sequences (METPVVQPR and DWTCWSCLVCAACS) were obtained suggesting that the ∼9 and 6kDa correspond to the prebacteriocin and mature Tolworthcin 524, respectively. Sequences showed high identity with Thurincin H and Thuricin 17 and had a conserved motif with other bacteriocins of B. thuringiensis. Based on sequence data, Tolworthcin 524 was classified in subclass II.2 (Thuricin-like peptides) of the Bacillus bacteriocin classification scheme. The larger peptide did not harbor a sequence suggestive of a signal peptide neither did it contain the double-glycine (GG) motif characteristic of the secretion leader recognized by the ABC transport system. Implications of these properties in Tolworthcin 524 secretion are discussed. Copyright © 2014 Elsevier GmbH. All rights reserved.

  11. Detection of β-exotoxin synthesis in Bacillus thuringiensis using an easy bioassay with the nematode Caenorhabditis elegans.

    Science.gov (United States)

    Sánchez-Soto, A I; Saavedra-González, G I; Ibarra, J E; Salcedo-Hernández, R; Barboza-Corona, J E; Del Rincón-Castro, M C

    2015-12-01

    The insecticidal activity of Bacillus thuringiensis is owing to the action of Cry and Cyt proteins. In addition to the synthesis of insecticidal proteins, some strains are able to synthesize β-exotoxin, which is highly toxic to humans. In this regard, it is very important to have a simple method to detect β-exotoxin to avoid the commercial production of this type of strains. In this work, we developed a simple and fast method, using the nematode Caenorhabditis elegans to detect indirectly the synthesis of β-exotoxin by B. thuringiensis strain. Using this assay, we detected that ~60% of Mexican native strains (i.e. LBIT-471, 491, 492, 497, 507, 511, 515, 536 and 537) were toxic to the nematode (44-97% mortalities) and their β-exotoxin (βEx(+) ) production, including a positive control (NRD-12), was confirmed by HPLC. In addition, the negative controls (βEx(-) ) LBIT-436 (HD-1) and LBIT-438 and also the native strains LBIT-499, 500, 521, 522, 533 and 542, did not show a detrimental effect against nematodes larvae, neither the synthesis of β-exotoxin as determined by HPLC. Finally, we did not find a correlation between B. thuringiensis strains with similar plasmid patterns and the β-exotoxin production. In this work, we implemented a qualitative and fast bioassay using the nematode Caenorhabditis elegans to detect the production of β-exotoxin in different strains of Bacillus thuringiensis. We show that this assay is useful to detect β-exotoxin in B. thuringiensis with high reliability, helping to discriminate strains that could not be used as bioinsecticides because of their putative risk to humans. Data show that qualitative bioassay with nematodes is a potential alternative to fly larvae bioassays, and correlated with the determination of β-exotoxin by HPLC. © 2015 The Society for Applied Microbiology.

  12. A strong promoter of a non-cry gene directs expression of the cry1Ac gene in Bacillus thuringiensis.

    Science.gov (United States)

    Zhang, Xin; Gao, Tantan; Peng, Qi; Song, Lai; Zhang, Jie; Chai, Yunrong; Sun, Dongmei; Song, Fuping

    2018-04-01

    Bacillus thuringiensis bacteria show insecticidal activities that rely upon the production of insecticidal crystal proteins, which are encoded by cry or cyt genes and can target a variety of insect pests. It has been shown that cry1Ac is the only cry gene in B. thuringiensis subsp. kurstaki HD73 (B. thuringiensis HD73) and its expression is controlled by both σ E and σ K . Here, we report a novel σ E -dependent strong promoter of a non-cry gene (HD73_5014), which can direct strong cry1Ac gene expression in B. thuringiensis HD73. We constructed an E. coli-B. thuringiensis shuttle vector (pHT315-P 5014 -1Ac) for cry1Ac gene expression, using the HD73_5014 gene promoter. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western blot analysis showed that expression of the cry1Ac gene directed by the HD73_5014 gene promoter was at the same level as that directed by the previously known strongest cry promoter, P cry8E . However, this strain did not form typical bipyramidal crystals in mother cells, as observed by transmission electron microscopy and atomic force microscope. The strain with Cry1Ac protein expression under the control of the HD73_5014 gene promoter (P 5014 -cry1Ac) showed insecticidal activity against Plutella xylostella similar to that under the control of the orf1cry8E gene promoter (P cry8E -cry1Ac). Collectively, these results suggest that the HD73_5014 gene promoter, as a non-cry gene promoter, would be an efficient transcriptional element for cry gene expression. These data also show the possibility for improving Cry production by searching for transcriptional elements in not only cry genes, but also non-cry genes.

  13. Larvicidal Activities of Indigenous Bacillus thuringiensis Isolates and Nematode Symbiotic Bacterial Toxins against the Mosquito Vector, Culex pipiens (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Ashraf M Ahmed

    2017-06-01

    Full Text Available Background: The incidence of mosquito-borne diseases and the resistance of mosquitoes to conventional pesticides have recently caused a panic to the authorities in the endemic countries. This study was conducted to identify native larvicidal biopesticides against Culex pipiens for utilization in the battle against mosquito-borne diseases.Methods: Larvicidal activities of new indigenous Bacillus thuringiensis isolates and crude toxin complexes (TCs of two nematode bacterial-symbionts, Photorhabdus luminescens akhurstii (HRM1 and Ph. luminescens akhurstii (HS1 that tested against Cx. pipiens. B. thuringiensis isolates were recovered from different environmental samples in Saudi Arabia, and the entomopathogenic nematodes, Heterorhabditis indica (HRM1 and He. sp (HS1 were iso­lated from Egypt. Larvicidal activities (LC50 and LC95 of the potentially active B. thuringiensis strains or TCs were then evaluated at 24 and 48h post-treatment.Results: Three B. thuringiensis isolates were almost as active as the reference B. thuringiensis israelensis (Bti-H14, and seven isolates were 1.6–5.4 times more toxic than Bti-H14. On the other hand, the TCs of the bacterial sym­bionts, HRM1 and HS1, showed promising larvicidal activities. HS1 showed LC50 of 2.54 folds that of HRM1 at 24h post-treatment. Moreover, histopathological examinations of the HS1-treated larvae showed deformations in midgut epithelial cells at 24h post-treatment.Conclusion: Synergistic activity and molecular characterization of these potentially active biocontrol agents are currently being investigated. These results may lead to the identification of eco-friend mosquito larvicidal product(s that could contribute to the battle against mosquito-borne diseases.

  14. Prevalence and characterization of multi-drug resistant Salmonella Enterica serovar Gallinarum biovar Pullorum and Gallinarum from chicken

    Directory of Open Access Journals (Sweden)

    Md. Shafiullah Parvej

    2016-01-01

    Full Text Available Aim: Salmonella is an important zoonotic pathogen responsible for animal and human diseases. The aim of the present study was to determine the prevalence and stereotyping of Salmonella isolates isolated from apparently healthy poultry. Furthermore, the clonal relatedness among the isolated Salmonella serovars was assessed. Materials and Methods: A total of 150 cloacal swab samples from apparently healthy chickens were collected, and were subjected for the isolation and identification of associated Salmonella organisms. The isolated colonies were identified and characterized on the basis of morphology, cultural characters, biochemical tests, slide agglutination test, polymerase chain reaction, and pulsed-field gel electrophoresis (PFGE. Antibiotic sensitivity patterns were also investigated using commonly used antibiotics. Results: Of the 150 samples, 11 (7.33% produced characteristics pink colony with black center on XLD agar medium, and all were culturally and biochemically confirmed to be Salmonella. All possessed serovar-specific gene SpeF and reacted uniformly with group D antisera, suggesting that all of the isolates were Salmonella Enterica serovar Gallinarum, biovar Pullorum and/or Gallinarum. Antimicrobial susceptibility testing revealed that 54.54% of the isolated Salmonella Enterica serovars were highly sensitive to ciprofloxacin, whereas the 81.81% isolates were resistant to amoxycillin, doxycycline, kanamycin, gentamycin, and tetracycline. Pulsed-field gel electrophoresis of the XbaI-digested genomic DNA exhibited identical banding patterns, suggesting that the multidrug resistant Salmonella Enterica serovars occurring in commercial layers are highly clonal in Bangladesh. Conclusion: The present study was conducted to find out the prevalence of poultry Salmonella in layer chicken and to find out the clonal relationship among them. The data in this study suggest the prevalence of Salmonella Enterica, which is multidrug resistant and

  15. Proteolysis, histopathological effects, and immunohistopathological localization of delta-endotoxins of Bacillus thuringiensis subsp. kurstaki in the midgut of lepidopteran olive tree pathogenic insect Prays oleae.

    Science.gov (United States)

    Rouis, S; Chakroun, M; Saadaoui, I; Jaoua, S

    2007-02-01

    Considering the fact that Prays oleae is one of the most pathogenic insects to the olive tree in the Mediterranean basin, particularly in Tunisia, the mode of action of Cry insecticidal toxins of Bacillus thuringiensis kurstaki in Prays oleae midgut was investigated. The proteolysis of Bacillus thuringiensis delta-endotoxins in the midgut was a key step in determining their potency against Prays oleae. The latter's proteases activated the delta-endotoxins early, yielding stable toxins. The in vitro and in vivo binding of these toxins to Prays oleae larvae midgut was studied immunohistochemically, evidencing a midgut columnar cell vacuolization, microvilli damage, and then a pass of epithelium cell content into the larvae midgut. Moreover, Bacillus thuringiensis toxins were shown to bind to the apical microvilli of the midgut epithelial cells. The in vitro study of the interaction of Prays oleae midgut proteins with biotinylated Bacillus thuringiensis toxins allowed the prediction of four suitable receptor proteins in Prays oleae.

  16. Lack of detrimental effects of Bacillus thuringiensis Cry toxins on the insect predator Chrysoperla carnea: a toxicological, histopathological, and biochemical analysis

    NARCIS (Netherlands)

    Rodrigo-Simón, A.; Maagd, de R.A.; Avilla, C.; Bakker, P.L.; Molthoff, J.W.; González-Zamora, J.; Ferré, J.

    2006-01-01

    The effect of Cry proteins of Bacillus thuringiensis on the green lacewing (Chrysoperla carnea) was studied by using a holistic approach which consisted of independent, complementary experimental strategies. Tritrophic experiments were performed, in which lacewing larvae were fed Helicoverpa

  17. Susceptibility of the endangered Karner blue butterfly (Lepidoptera: Lycaenidae) to Bacillus thuringiensis var. kurstaki used for gypsy moth suppression in Michigan

    Science.gov (United States)

    Catherine Papp Herms; Deborah G. McCullough; Leah S. Bauer; Robert A. Haack; Norman R. Dubois

    1997-01-01

    We investigated the phenological and physiological susceptibility of the endangered Karner blue butterfly (Lycaeides melissa samuelis) to Bacillus thuringiensis var. kurstaki (Bt), a product widely used for gypsy moth (Lymantria dispar) suppression in Michigan and other infested states. We...

  18. Natural phytosanitary products effects on Bacillus Thuringiensis SUBSP. Kurstaki (BerlinerEfeito de produtos fitossanitários naturais sobre Bacillus Thuringiensis subesp. Kurstaki (Berliner

    Directory of Open Access Journals (Sweden)

    Everton Ricardi Lozano da Silva

    2012-12-01

    Full Text Available This work aimed to evaluate the effect of natural phytossanitary products (NPP on spores and crystal toxicity of Bacillus thuringiensis subsp. kurstaki – HD1 (Btk. For this commercial products (Agromos, Biogermex, Bovemax, Bordeaux mixture, Ecolife®, Dalneen, Matan Plus, Pyronin and Stüble-Aid® were used at three different concentrations. The effect of NPP on spores was assessed by comparing a suspension of Btk + NPP with sterile distilled water (SDW and another suspension with nutrient broth (NB, inoculated on nutrient agar (NA in Petri dishes to quantify the number of CFU/mL, 18 h after inoculation and incubation. The effect of NPP on crystals was evaluated with a suspension of Btk+SDW+NPP added to the artificial diet supplied for Anticarsia gemmatalis Hub. (Lepidoptera: Noctuidae quantifying the number of dead larvae at 12, 24, 48 and 72 h. Matan Plus was the only natural product that did not present effect on spores. All other products, regardless of concentration, decreased significantly CFU/mL Regarding crystals, Bordeaux mixture was the only one that reduced significantly Btk insecticidal activity at three concentrations. Este trabalho objetivou avaliar o efeito dos produtos fitossanitários naturais (PFN sobre esporos e sobre a toxicidade dos cristais de Bacillus thuringiensis subespécie kurstaki – HD1 (Btk. Para tal foram usados os produtos comerciais (Agromos, Biogermex, Bovemax, Calda Bordalesa, Ecolife®, Dalneen, Matan Plus, Pironin e Stüble –Aid® em três diferentes concentrações. O efeito dos PFN sobre esporos foi avaliado comparando-se suspensões de Btk + PFN com água destilada esterelizada (ADE e suspensões com caldo nutriente (CB, inoculadas em agar nutriente (AN, em placas de Petri quantificando-se o número de unidades formadoras de colônias (UFC / mL, 18 h após a inoculação e incubação. O efeito dos PFN sobre cristais foi avaliado com suspensões de Btk + ADE + PFN adicionados à dieta artificial

  19. Study of the Bacillus thuringiensis Vip3Aa16 histopathological effects and determination of its putative binding proteins in the midgut of Spodoptera littoralis

    OpenAIRE

    Abdelkefi-Mesrati, Lobna; Boukedi, Hanen; Dammak-Karray, Mariam; Sellami-Boudawara, Tahya; Jaoua, Samir; Tounsi, Slim

    2011-01-01

    The bacterium Bacillus thuringiensis produces, at the vegetative stage of its growth, Vip3A proteins with activity against a broad spectrum of lepidopteran insects. The Egyptian cotton leaf worm (Spodoptera littoralis) is an important agricultural pest that is susceptible to the Vip3Aa16 protein of Bacillus thuringiensis kurstaki strain BUPM95. The midgut histopathology of Vip3Aa fed larvae showed vacuolization of the cytoplasm, brush border membrane destruction, vesicle formation in the apic...

  20. The Synergist Effect of The Henna Plant, Lawsonia alba on Bacillus thuringiensis var. kurstaki Against Third Larval Instar of Pistachio Leaf Borer, Ocneria terebinthina Strg. (Lep.: Lymanteriidae)

    OpenAIRE

    Zahra Sheibani

    2017-01-01

    Ocneria terebinthina Strg. (Lep.: Lymanteriidae) is a leaf borer pest in pistachio orchard. The toxicity of Bacillus thuringiensis var. kurstaki alone and in combination with henna powder was investigated on third larval instar of O. terebinthina under laboratory conditions. Bioassay was carried out using spray technique on pistachio offshoot. Probit analysis of concentration-mortality data was conducted to estimate the LC50 value. The LC50 value of B. thuringiensis on third instar of larvae ...

  1. High resolution clustering of Salmonella enterica serovar Montevideo strains using a next-generation sequencing approach

    Directory of Open Access Journals (Sweden)

    Allard Marc W

    2012-01-01

    Full Text Available Abstract Background Next-Generation Sequencing (NGS is increasingly being used as a molecular epidemiologic tool for discerning ancestry and traceback of the most complicated, difficult to resolve bacterial pathogens. Making a linkage between possible food sources and clinical isolates requires distinguishing the suspected pathogen from an environmental background and placing the variation observed into the wider context of variation occurring within a serovar and among other closely related foodborne pathogens. Equally important is the need to validate these high resolution molecular tools for use in molecular epidemiologic traceback. Such efforts include the examination of strain cluster stability as well as the cumulative genetic effects of sub-culturing on these clusters. Numerous isolates of S. Montevideo were shot-gun sequenced including diverse lineage representatives as well as numerous replicate clones to determine how much variability is due to bias, sequencing error, and or the culturing of isolates. All new draft genomes were compared to 34 S. Montevideo isolates previously published during an NGS-based molecular epidemiological case study. Results Intraserovar lineages of S. Montevideo differ by thousands of SNPs, that are only slightly less than the number of SNPs observed between S. Montevideo and other distinct serovars. Much less variability was discovered within an individual S. Montevideo clade implicated in a recent foodborne outbreak as well as among individual NGS replicates. These findings were similar to previous reports documenting homopolymeric and deletion error rates with the Roche 454 GS Titanium technology. In no case, however, did variability associated with sequencing methods or sample preparations create inconsistencies with our current phylogenetic results or the subsequent molecular epidemiological evidence gleaned from these data. Conclusions Implementation of a validated pipeline for NGS data acquisition and

  2. Salmonella enterica subsp. salamae serovar Sofia, a prevalent serovar in Australian broiler chickens, is also capable of transient colonisation in layers.

    Science.gov (United States)

    Cooper, Caitlin; Moore, Robert J; Chandry, P Scott; Fegan, Narelle

    2018-03-14

    1. Salmonella enterica subsp. salamae serovar sofia (S. sofia) is a prevalent strain of Salmonella in Australian broilers and has been isolated from broiler chickens, litter, dust, as well as pre- and post-processing carcasses, and retail chicken portions but has never been reported in commercial Australian layers or eggs. 2. To investigate whether a S. sofia isolate from a broiler could colonise layers, one-month-old Hyline brown layers were orally inoculated with S. sofia and colonisation was monitored for 2-4 weeks. 3. Overall, 30-40% of the chickens shed S. sofia from the cloaca between 6 and 14 d post-inoculation which then declined to 10% by d 21. Necropsy at 2 weeks post-inoculation revealed 80% of birds harboured S. sofia in the caecum, whilst, by 4 weeks post-infection, no chickens were colonised with S. sofia in the gastrointestinal tract, liver or spleen. Additionally, no aerosol 'bird to bird' transfer was evident. 4. This study demonstrated that laying hens can be colonised by broiler-derived S. sofia; however, this colonisation was transient, reaching a peak at 14 d post-inoculation, and was completely cleared by 28 d post-inoculation. The transience of colonisation of S. sofia in layers could be a factor explaining why S. sofia has never been detected when screening for Salmonella serotypes found in Australian laying hens or eggs.

  3. Impact of UV radiation on activity of linear furanocoumarins and Bacillus thuringiensis var. kurstaki against Spodoptera exigua: Implications for tritrophic interactions

    International Nuclear Information System (INIS)

    Trumble, J.T.; Moar, W.J.; Brewer, M.J.; Carson, W.G.

    1991-01-01

    Acidic fogs with a pH of 2.0 and duration of 2 hr did not reduce the efficacy of Bacillus thuringiensis var. kurstaki. Therefore, the impact of UV radiation was investigated on the interactions between (1) levels of the antibacterial linear furanocoumarins psoralen, bergapten, and xanthotoxin in Apium graveolens (L.) occurring following a 2.0 pH acidic fog episode, (2) the noctuid Spodoptera exigua, and (3) a sublethal dosage of the microbial pathogen B. thuringiensis var. kurstaki. Mean time to pupation in the absence of UV radiation was significantly extended by the addition of either psoralens or B. thuringiensis. Larvae developing on diets containing B. thuringiensis plus psoralens required nearly 40% longer to pupate than controls, but their effects were additive as the interaction was not significant. Mean time to mortality, a weighted average time of death, was not significantly affected by any of the treatments. In a 2 x 2 x 2 factorial analysis, all main effects reduced survival significantly, as did the three-way interaction. Thus, antagonistic interactions with psoralens that would reduce the effectiveness of B. thuringiensis in the field were not observed. When pairs of main effects were nested within the two levels of the third factor, several two-way interactions were found. Interestingly, the activity of B. thuringiensis and the psoralens, individually or in combination, was enhanced by exposure to UV radiation. Implications of this research are discussed for both natural and agricultural ecosystems

  4. Impact of UV radiation on activity of linear furanocoumarins and Bacillus thuringiensis var. kurstaki against Spodoptera exigua: Implications for tritrophic interactions

    Energy Technology Data Exchange (ETDEWEB)

    Trumble, J.T.; Moar, W.J.; Brewer, M.J.; Carson, W.G. (Univ. of California, Riverside (United States))

    1991-05-01

    Acidic fogs with a pH of 2.0 and duration of 2 hr did not reduce the efficacy of Bacillus thuringiensis var. kurstaki. Therefore, the impact of UV radiation was investigated on the interactions between (1) levels of the antibacterial linear furanocoumarins psoralen, bergapten, and xanthotoxin in Apium graveolens (L.) occurring following a 2.0 pH acidic fog episode, (2) the noctuid Spodoptera exigua, and (3) a sublethal dosage of the microbial pathogen B. thuringiensis var. kurstaki. Mean time to pupation in the absence of UV radiation was significantly extended by the addition of either psoralens or B. thuringiensis. Larvae developing on diets containing B. thuringiensis plus psoralens required nearly 40% longer to pupate than controls, but their effects were additive as the interaction was not significant. Mean time to mortality, a weighted average time of death, was not significantly affected by any of the treatments. In a 2 {times} 2 {times} 2 factorial analysis, all main effects reduced survival significantly, as did the three-way interaction. Thus, antagonistic interactions with psoralens that would reduce the effectiveness of B. thuringiensis in the field were not observed. When pairs of main effects were nested within the two levels of the third factor, several two-way interactions were found. Interestingly, the activity of B. thuringiensis and the psoralens, individually or in combination, was enhanced by exposure to UV radiation. Implications of this research are discussed for both natural and agricultural ecosystems.

  5. Produccion por tecnologia de fermentacion de bacillus thuringiensis utilizando medios alternativos

    Directory of Open Access Journals (Sweden)

    Yaneth Amparo Muñoz-Peñalosa

    2000-01-01

    Full Text Available In the production by fermentation technology Bacillus thuringiensis of five alternative methods they were studied. The results of cell growth, working-level 100ml in static culture and temperature of 28 ° C, mostraronque the optimal substrate corresponded to the environment in which molasses and rice powder was added (alternative Medium No. 1] The cell development using 100 ml of substrate was studied with reciprocating shaking 110 rpm. in this test was determined filter curve creciemiento medio.The inoculum, allowed tiempode set the process in 6 hours. For the development of fermentations, are counted with the experimental equipment, glass bioreactor in two liters of capacity and aeration devices, mechanical stirring, sampling and output gases.The fermentation in the production of Bacillus thuringiensis is the type discontinuous submerged aerobic process and growth into account .Teniendo bibliographic information and preliminary results of the study, fixed working parameters were determined for production by fermentation of Bacillus thuringiensis, being alternative means No. 1, volume 1 liter temperature 28 ° C and cell concentration of the inoculum. To determine the optimum parameters of fermantacion was used a factorial design of experiments of the type 22, (two variables at two levels, with aeration (3.2-0.5 VVM and agitation (110-210 rpm .The fermentations performed 7, 4 design and 3 the average level of the variables. For monitoring fermentation sample was taken every 12 hours and cell concentration (Chamber of Neuvauer and pH was analyzed. The results of cell concentration measurement for fermentations at 60 hours shows that optimum working conditions and limitations correspond to the values ​​of the variable, 3.2 VVM aeration and agitation 210 Variable rpm.Significant was the aeration of pH in the fermentation media change neutral to acid and ended as a staple. A fermentations I were efectuo controlde microbiological quality, Gram

  6. Biochemical, immunological and toxicological characteristics of the crystal proteins of Bacillus thuringiensis subsp. medellin

    Directory of Open Access Journals (Sweden)

    Sergio Orduz

    1996-04-01

    Full Text Available Characterization of the insecticidal and hemolytic activity of solubilized crystal proteins of Bacillus thuringiensis (Bt subsp. medellin (Btmed was performed and compared to solubilized crystal proteins of isolates 1884 of B. thuringiensis subsp. israelensis (Bti and isolate PG-14 of B. thuringiensis subsp. morrisoni (Btm. In general, at acid pH values solubilization of the Bt crystalline parasporal inclusions (CPI was lower than at alkaline pH. The larvicidal activity demonstrated by the CPI of Btmed indicated that optimal solubilization of CPI takes place at a pH value of 11.3, in Bti at pH values from 5.03 to 11.3 and in Btm at pH values from 9.05 to 11.3. Hemolytic activity against sheep red blood cells was mainly found following extraction at pH 11.3 in all Bt strains tested. Polyacrylamide gel electrophoresis under denaturing conditions revealed that optimal solubilization of the CPI in all Bt strains takes place at the alkaline pH values from 9.05 to 11.3. An enriched preparation of Btmed crystals was obtained, solubilized and crystal proteins were separated on a size exclusion column (Sephacryl S-200. Three main protein peaks were observed on the chromatogram. The first peak had two main proteins that migrate between 90 to 100 kDa. These proteins are apparently not common to other Bt strains isolated to date. The second and third peaks obtained from the size exclusion column yielded polypeptides of 68 and 28-30 kDa, respectively. Each peak independently, showed toxicity against 1st instar Culex quinquefasciatus larvae. Interestingly, combinations of the fractions corresponding to the 68 and 30 kDa protein showed an increased toxicity. These results suggest that the 94 kDa protein is an important component of the Btmed toxins with the highest potency to kill mosquito larvae. When crystal proteins of Bti were probed with antisera raised independently against the three main protein fractions of Btmed, the only crystal protein that showed

  7. Global Monitoring of Salmonella Serovar Distribution from the World Health Organization Global Foodborne Infections Network Country Data Bank: Results of Quality Assured Laboratories from 2001 to 2007

    DEFF Research Database (Denmark)

    Hendriksen, Rene S.; Vieira, Antonio; Karlsmose, Susanne

    2011-01-01

    most frequently identified serovars of Salmonella isolated from humans from 2001 to 2007 in laboratories from 37 countries that participated in World Health Organization Global Foodborne Infections Network and demonstrated serotyping proficiency in the Global Foodborne Infections Network External...

  8. Complete genome sequence of the thermotolerant foodborne pathogen Salmonella enterica serovar Senftenberg ATCC 43845 and phylogenetic analysis of loci encoding thermotolerance

    Science.gov (United States)

    Introduction: Previous studies in Cronobacter sakazakii, Klebsiella spp., and Escherichia coli have identified a genomic island that confers thermotolerance to its hosts. This island has recently been identified in Salmonella enterica serovar Senfentenberg ATCC 43845, a historically important, heat ...

  9. Survival and transmission of Salmonella enterica serovar typhimurium in an outdoor organic pig farming environment

    DEFF Research Database (Denmark)

    Jensen, Annette Nygaard; Dalsgaard, Anders; Stockmarr, Anders

    2006-01-01

    , which caused substantial contamination of the environment. This suggests that isolation of animals as soon as a Salmonella infection is indicated by clinical symptoms of diarrhea could be a means of reducing and controlling the spread and persistence of Salmonella in outdoor organic pig production......It was investigated how organic rearing conditions influence the Salmonella enterica infection dynamics in pigs and whether Salmonella persists in the paddock environment. Pigs inoculated with S. enterica serovar Typhimurium were grouped with Salmonella-negative tracer pigs. Bacteriological...... of Salmonella-negative pigs into four naturally Salmonella-contaminated paddocks caused Salmonella infections of pigs in two paddocks. In one of these paddocks, all tracer pigs (n = 10) became infected, coinciding with a previous high Salmonella infection rate and high Salmonella excretion level. Our results...

  10. Chlamydia trachomatis C-complex serovars are a risk factor for preterm birth

    DEFF Research Database (Denmark)

    Hollegaard, Stine; Vogel, Ida; Thorsen, Poul

    2007-01-01

    BACKGROUND: Potential associations between current or previous C. trachomatis infections (general IgG and serovars) and spontaneous preterm birth (PTB) were examined and associations between C. trachomatis infections and previous fertility problems were explored. PATIENTS AND METHODS: At week 17......, Chlamydia antigen, Chlamydia IgG, Chlamydia complex B, C and GF levels were measured. Spontaneous preterm birth (...) and odds ratios (OR) were estimated by logistic regression. RESULTS: C. trachomatis C-complex positivity was associated with spontaneous PTB [RR 2.6 (1.1-6.29)] and additionally with a prior history of subfertility [OR 4.4 [2.5-7.7]), infertility treatment [OR 7.2 (4.0-12.8)] and ectopic pregnancy [5.2 (2...

  11. Microgravity as a novel environmental signal affecting Salmonella enterica serovar Typhimurium virulence

    Science.gov (United States)

    Nickerson, C. A.; Ott, C. M.; Mister, S. J.; Morrow, B. J.; Burns-Keliher, L.; Pierson, D. L.

    2000-01-01

    The effects of spaceflight on the infectious disease process have only been studied at the level of the host immune response and indicate a blunting of the immune mechanism in humans and animals. Accordingly, it is necessary to assess potential changes in microbial virulence associated with spaceflight which may impact the probability of in-flight infectious disease. In this study, we investigated the effect of altered gravitational vectors on Salmonella virulence in mice. Salmonella enterica serovar Typhimurium grown under modeled microgravity (MMG) were more virulent and were recovered in higher numbers from the murine spleen and liver following oral infection compared to organisms grown under normal gravity. Furthermore, MMG-grown salmonellae were more resistant to acid stress and macrophage killing and exhibited significant differences in protein synthesis than did normal-gravity-grown cells. Our results indicate that the environment created by simulated microgravity represents a novel environmental regulatory factor of Salmonella virulence.

  12. Risk factors associated with Salmonella enterica serovar typhimurium infection in Danish broiler flocks

    DEFF Research Database (Denmark)

    Skov, M. N.; Angen, Øystein; Chriel, M.

    1999-01-01

    A retrospective longitudinal study was conducted to identify risk factors associated with Salmonella enterica serovar typhimurium (S. typhimurium) infection in Danish broiler flocks. The data included all broiler flocks slaughtered in 1995, and the epidemiological unit was the individual broiler...... for analysis. Five factors and an interaction term were found significant by multivariate logistic regression analysis. An increased risk for S, typhimurium infection was associated with two parent flocks, one confirmed infected and one suspected of being infected with S. typhimurium, with two...... of the hatcheries, and with five houses on the farm. An interaction between season anal the previously mentioned hatcheries, and a random effect at farm level was also found to be statistically significant. Twelve variables were not found to be associated with S, typhimurium infection: medication, growth promoters...

  13. Survey of Salmonella serovars in broilers and laying breeding reproducers in East of Algeria.

    Science.gov (United States)

    Ammar, Ayachi; Alloui, Nadir; Bennoune, Omar; Kassah-Laouar, Ahmed

    2010-03-08

    Avian salmonellosis affects the poultry industry in underdeveloped and in developed countries. The aim of this study was to identify the most common Salmonella serovars in broilers and laying breeding reproducers in Eastern Algeria according to the ISO 6579 method. A total of 294 samples were obtained from two flocks of 10,000 broilers and laying breeding reproducers. Samples included livers and spleens, drag swabs of bottom boxes of young chickens, cloacal swabs, and faecal samples of chickens. Additional samples were also taken from water, feed and dusty surfaces. Only the cloacal swabs, poultry faeces and samples from dusty surfaces were positive for Salmonella Typhimurium and Salmonella Livingstone with a detection rate of 12% and 1.6% respectively. The results showed evidence of legislative failure regarding biosafety within the poultry industry in the area of Batna, Eastern Algeria.

  14. Risk factors associated with Salmonella enterica serovar typhimurium infection in Danish broiler flocks

    DEFF Research Database (Denmark)

    Skov, M. N.; Angen, Øystein; Chriel, M.

    1999-01-01

    A retrospective longitudinal study was conducted to identify risk factors associated with Salmonella enterica serovar typhimurium (S. typhimurium) infection in Danish broiler flocks. The data included all broiler flocks slaughtered in 1995, and the epidemiological unit was the individual broiler...... flock. The S. typhimurium status was determined by microbiological examination of 60 fresh fecal samples. This procedure should detect an infected flock with a probability above 95%, if the prevalence is above 5%, and given that the sensitivity of the test is 100%. Nineteen variables were selected...... for analysis. Five factors and an interaction term were found significant by multivariate logistic regression analysis. An increased risk for S, typhimurium infection was associated with two parent flocks, one confirmed infected and one suspected of being infected with S. typhimurium, with two...

  15. Antimicrobial resistance in Salmonella enterica subsp. enterica serovar typhimurium from humans and production animals

    DEFF Research Database (Denmark)

    Seyfarth, Anne Mette; Wegener, Henrik Caspar; FrimodtMoller, N.

    1997-01-01

    .4% of strains from cattle, 11.1% of strains from pigs and 9.2% of strains from poultry. Multiple resistance, i.e. resistance against at least four antimicrobial agents, was found in 9.2% of the human strains, but in only two of the cattle isolates, The majority of the multi-resistant strains in humans were from......: Poultry strains were usually resistant only to ampicillin, white pig and cattle isolates were most often resistant to sulphonamide, tetracycline and streptomycin. Typing of the strains showed that some animal strains and human strains were indistinguishable. In conclusion, while antimicrobial resistance......We have studied the frequency of antimicrobial resistance and epidemiological relatedness among 473 isolates of Salmonella enterica subsp, enterica serovar typhimurium (S. typhimurium) from human and veterinary sources. The human strains were clinical isolates from patients with diarrhoea sent...

  16. Antimicrobial resistance in Salmonella enterica subsp. enterica serovar typhimurium from humans and production animals

    DEFF Research Database (Denmark)

    Seyfarth, Anne Mette; Wegener, Henrik Caspar; FrimodtMoller, N.

    1997-01-01

    infections contracted outside Denmark, most often in southern Europe or south-east Asia. Resistance in human strains was most common against tetracycline (13%), ampicillin (12%), sulphonamide (12%), streptomycin (10%) and chloramphenicol (8%). The resistance pattern differed somewhat in animal isolates......: Poultry strains were usually resistant only to ampicillin, white pig and cattle isolates were most often resistant to sulphonamide, tetracycline and streptomycin. Typing of the strains showed that some animal strains and human strains were indistinguishable. In conclusion, while antimicrobial resistance......We have studied the frequency of antimicrobial resistance and epidemiological relatedness among 473 isolates of Salmonella enterica subsp, enterica serovar typhimurium (S. typhimurium) from human and veterinary sources. The human strains were clinical isolates from patients with diarrhoea sent...

  17. Complete Genome Sequence of Salmonella enterica subsp. enterica Serovar Agona 460004 2-1, Associated with a Multistate Outbreak in the United States.

    Science.gov (United States)

    Hoffmann, Maria; Payne, Justin; Roberts, Richard J; Allard, Marc W; Brown, Eric W; Pettengill, James B

    2015-07-02

    Within the last several years, Salmonella enterica subsp. enterica serovar Agona has been among the 20 most frequently isolated serovars in clinical cases of salmonellosis. In this report, the complete genome sequence of S. Agona strain 460004 2-1 isolated from unsweetened puffed-rice cereal during a multistate outbreak in 2008 was sequenced using single-molecule real-time DNA sequencing. Copyright © 2015 Hoffmann et al.

  18. Functional analysis of genes in the rfb locus of Leptospira borgpetersenii serovar Hardjo subtype Hardjobovis.

    Science.gov (United States)

    Bulach, D M; Kalambaheti, T; de la Peña-Moctezuma, A; Adler, B

    2000-07-01

    Lipopolysaccharide (LPS) is a key antigen in immunity to leptospirosis. Its biosynthesis requires enzymes for the biosynthesis and polymerization of nucleotide sugars and the transport through and attachment to the bacterial membrane. The genes encoding these functions are commonly clustered into loci; for Leptospira borgpetersenii serovar Hardjo subtype Hardjobovis, this locus, named rfb, spans 36.7 kb and contains 31 open reading frames, of which 28 have been assigned putative functions on the basis of sequence similarity. Characterization of the function of these genes is hindered by the fact that it is not possible to construct isogenic mutant strains in Leptospira. We used two approaches to circumvent this problem. The first was to clone the entire locus into a heterologous host system and determine if a "recombinant" LPS or polysaccharide was synthesized in the new host. The second approach used putative functions to identify mutants in other bacterial species whose mutations might be complemented by genes on the leptospiral rfb locus. This approach was used to investigate the function of three genes in the leptospiral rfb locus and demonstrated function for orfH10, which complemented a wbpM strain of Pseudomonas aeruginosa, and orfH13, which complemented an rfbW strain of Vibrio cholerae. However, despite the similarity of OrfH11 to WecC, a wecC strain of E. coli was not complemented by orfH11. The predicted protein encoded by orfH8 is similar to GalE from a number of organisms. A Salmonella enterica serovar Typhimurium strain producing no GalE was used as a background in which orfH8 produced detectable GalE enzyme activity.

  19. Differential Killing of Salmonella enterica Serovar Typhi by Antibodies Targeting Vi and Lipopolysaccharide O:9 Antigen

    Science.gov (United States)

    Hart, Peter J.; O’Shaughnessy, Colette M.; Siggins, Matthew K.; Bobat, Saeeda; Kingsley, Robert A.; Goulding, David A.; Crump, John A.; Reyburn, Hugh; Micoli, Francesca; Dougan, Gordon; Cunningham, Adam F.; MacLennan, Calman A.

    2016-01-01

    Salmonella enterica serovar Typhi expresses a capsule of Vi polysaccharide, while most Salmonella serovars, including S. Enteritidis and S. Typhimurium, do not. Both S. Typhi and S. Enteritidis express the lipopolysaccharide O:9 antigen, yet there is little evidence of cross-protection from anti-O:9 antibodies. Vaccines based on Vi polysaccharide have efficacy against typhoid fever, indicating that antibodies against Vi confer protection. Here we investigate the role of Vi capsule and antibodies against Vi and O:9 in antibody-dependent complement- and phagocyte-mediated killing of Salmonella. Using isogenic Vi-expressing and non-Vi-expressing derivatives of S. Typhi and S. Typhimurium, we show that S. Typhi is inherently more sensitive to serum and blood than S. Typhimurium. Vi expression confers increased resistance to both complement- and phagocyte-mediated modalities of antibody-dependent killing in human blood. The Vi capsule is associated with reduced C3 and C5b-9 deposition, and decreased overall antibody binding to S. Typhi. However, purified human anti-Vi antibodies in the presence of complement are able to kill Vi-expressing Salmonella, while killing by anti-O:9 antibodies is inversely related to Vi expression. Human serum depleted of antibodies to antigens other than Vi retains the ability to kill Vi-expressing bacteria. Our findings support a protective role for Vi capsule in preventing complement and phagocyte killing of Salmonella that can be overcome by specific anti-Vi antibodies, but only to a limited extent by anti-O:9 antibodies. PMID:26741681

  20. Differential Killing of Salmonella enterica Serovar Typhi by Antibodies Targeting Vi and Lipopolysaccharide O:9 Antigen.

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    Peter J Hart

    Full Text Available Salmonella enterica serovar Typhi expresses a capsule of Vi polysaccharide, while most Salmonella serovars, including S. Enteritidis and S. Typhimurium, do not. Both S. Typhi and S. Enteritidis express the lipopolysaccharide O:9 antigen, yet there is little evidence of cross-protection from anti-O:9 antibodies. Vaccines based on Vi polysaccharide have efficacy against typhoid fever, indicating that antibodies against Vi confer protection. Here we investigate the role of Vi capsule and antibodies against Vi and O:9 in antibody-dependent complement- and phagocyte-mediated killing of Salmonella. Using isogenic Vi-expressing and non-Vi-expressing derivatives of S. Typhi and S. Typhimurium, we show that S. Typhi is inherently more sensitive to serum and blood than S. Typhimurium. Vi expression confers increased resistance to both complement- and phagocyte-mediated modalities of antibody-dependent killing in human blood. The Vi capsule is associated with reduced C3 and C5b-9 deposition, and decreased overall antibody binding to S. Typhi. However, purified human anti-Vi antibodies in the presence of complement are able to kill Vi-expressing Salmonella, while killing by anti-O:9 antibodies is inversely related to Vi expression. Human serum depleted of antibodies to antigens other than Vi retains the ability to kill Vi-expressing bacteria. Our findings support a protective role for Vi capsule in preventing complement and phagocyte killing of Salmonella that can be overcome by specific anti-Vi antibodies, but only to a limited extent by anti-O:9 antibodies.