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Sample records for thuringiensis subspecies israelensis

  1. A study of the effect of Bacillus thuringiensis serotype H14 (subspecies israelensis) delta endotoxin on Musca larva.

    Science.gov (United States)

    Mehrabi, Mohammad Reza; Zoghimofrad, Laya; Mazinani, Mahboubeh; Akbarzadeh, Azim; Rahimi, Amirabbas

    2015-01-01

    House flies (Musca domestica) are of major public health concern in areas with poor sanitation and hygiene conditions. Biological control through the use of parasitoids and pathogens is one of the alternatives to the use of chemical pesticides for control of insects of public health importance. The effects of the delta endotoxin of Bacillus thuringiensis on house fly larval mortality were studied. Gel filtration and SDS-PAGE methods were used for separation and purification of proteins. Delta endotoxin was incubated with larvae in concentrations of 0.43 mg/mL and 0.27 mg/mL in bioassay tests. The results of this study indicated protein crystal toxicity against larvae of the house fly. A concentration of 0.43 mg/mL of this toxin caused 100% mortality in house fly larvae. The LD50 amount of these toxins was calculated as 125 µg/g. The results of this study suggest that the use of the protein crystal including delta endotoxin of Bacillus thuringiensis serotype H14 is an effective weapon in the biological fight against the house fly.

  2. 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.

  3. 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

  4. 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 ...

  5. 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.

  6. 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 ...

  7. 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...

  8. 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.

  9. 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

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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.

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

    African Journals Online (AJOL)

    israelensis (Bti) to mitigate the effects of black fly bites. This study was aimed at ... Black-flies have been a concern in many countries because they vector Onchocerciasis (River blindness). Onchocerciasis is an ..... no continuation of the life cycle the number of the adults in the environment began to drop. The general.

  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. 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

  19. 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.

  20. Low translocation of Bacillus thuringiensis israelensis to inner organs in mice after pulmonary exposure to commercial biopesticide

    DEFF Research Database (Denmark)

    Barfod, Kenneth Klingenberg; Ørum-Smidt, Lasse; Krogfelt, Karen A.

    2010-01-01

    Translocation of viable cells from a Bacillus thuringiensis israelensis-based biopesticide to inner organs in a mouse model was studied. Mice were exposed to the originally formulated product through the lungs and gastrointestinal tract by intratracheal instillation. Colony forming units (CFU) were...... grown from lungs, caecum, spleen and liver on Bacillus cereus-specific agar (BCSA) after 24 h and finally determined to be biopesticide strain B. t. israelensis by large plasmid profile. No CFU were found in spleen or liver of the control mice or in any aerosol background or material. We have shown...... biopesticides in the future....

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

    Directory of Open Access Journals (Sweden)

    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.

  2. Production of the bioinsecticide Bacillus thuringiensis subsp. israelensis with deltamethrin increases toxicity towards mosquito larvae.

    Science.gov (United States)

    Tetreau, G; Patil, C D; Chandor-Proust, A; Salunke, B K; Patil, S V; Després, L

    2013-08-01

    Bacillus thuringiensis subsp. israelensis is a bioinsecticide used for larval mosquito control and it represents a safe alternative to chemical insecticides. Despite its environmental safety, it is less efficient and persistent than chemical insecticides. To bypass these limitations, we propose to combine the advantages of chemical and biological insecticides by producing Bti in a medium supplemented with a chemical insecticide (DDT, deltamethrin, permethrin, propoxur or temephos). Among the investigated insecticides, the addition of deltamethrin in the medium induced a higher toxicity (over 6.72-fold) of the composite deltamethrin-Bti towards mosquito larvae as compared to Bti alone. This was mainly due to the insertion of deltamethrin into the membranes of Bti spores, as evidenced by a quantification of membrane-extracted deltamethrin by HPLC. This composite larvicide is a promising tool to decrease the quantity of chemicals dispersed in the environment, to increase the efficacy of Bti and to facilitate its widespread use as a transition between chemical and biological insecticides. Further experiments are required to characterize the mechanisms that underline the incorporation of deltamethrin into Bti to optimize the production and the toxicity of this composite larvicide. This study is the first report of an increased efficacy of the mosquitocidal bioinsecticide Bacillus thuringiensis subsp. israelensis (Bti) when produced with a chemical insecticide. The results clearly demonstrate that deltamethrin is able to synergize the insecticidal activity of Bti through inclusion into spore membranes, reducing off-target and nonspecific toxicity occurring when the chemical is used alone as sprays. This new composite chemical-biological insecticide can become an invaluable tool as an intermediate between single chemical usage and the widespread use of Bti, notably in developing countries with limited financial resources for intensive mosquito control campaigns. © 2013

  3. Long lasting persistence of Bacillus thuringiensis Subsp. israelensis (Bti in mosquito natural habitats.

    Directory of Open Access Journals (Sweden)

    Mathieu Tilquin

    Full Text Available BACKGROUND: The detrimental effects of chemical insecticides on the environment and human health have lead to the call for biological alternatives. Today, one of the most promising solutions is the use of spray formulations based on Bacillus thuringiensis subsp. israelensis (Bti in insect control programs. As a result, the amounts of Bti spread in the environment are expected to increase worldwide, whilst the common belief that commercial Bti is easily cleared from the ecosystem has not yet been clearly established. METHODOLOGY/MAIN FINDINGS: In this study, we aimed to determine the nature and origin of the high toxicity toward mosquito larvae found in decaying leaf litter collected in several natural mosquito breeding sites in the Rhône-Alpes region. From the toxic fraction of the leaf litter, we isolated B. cereus-like bacteria that were further characterized as B. thuringiensis subsp. israelensis using PCR amplification of specific toxin genes. Immunological analysis of these Bti strains showed that they belong to the H14 group. We finally used amplified length polymorphism (AFLP markers to show that the strains isolated from the leaf litter were closely related to those present in the commercial insecticide used for field application, and differed from natural worldwide genotypes. CONCLUSIONS/SIGNIFICANCE: Our results raise the issue of the persistence, potential proliferation and environmental accumulation of human-spread Bti in natural mosquito habitats. Such Bti environmental persistence may lengthen the exposure time of insects to this bio-insecticide, thereby increasing the risk of resistance acquisition in target insects, and of a negative impact on non-target insects.

  4. 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...

  5. Modular columns to study depth-dependence behavior of mosquito larvae and toxicity of Bacillus thuringiensis subsp. israelensis.

    Science.gov (United States)

    Meir, Michal; Ben-Dov, Eitan; Zaritsky, Arieh

    2011-03-01

    Modular transparent column system was designed to study depth-dependence behavior of mosquito larvae. The system was used in preliminary experiments to evaluate the effect of water depth on the larvicidal activity of Bacillus thuringiensis subsp. israelensis de Barjac against bottom feeder larvae of Aedes aegypti (Linn.) (Diptera: Culicidae), and suggestions for increasing the efficiency of the device are discussed. Copyright © 2010 Elsevier B.V. All rights reserved.

  6. 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

  7. 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.

  8. Toxicity and affecting factors of Bacillus thuringiensis var. israelensis on Chironomus kiiensis larvae.

    Science.gov (United States)

    Cao, Chuan-Wang; Sun, Li-Li; Wen, Rong-Rong; Li, Xiao-Peng; Wu, Hong-Qu; Wang, Zhi-Ying

    2012-01-01

    Abstract Bacillus thuringiensis var. israelensis (Bti) is a suitable agent for controlling Chironomus kiiensis, a major pest polluting water. In this study, laboratory bioassays were used to study toxicity and affecting factors of Bti on C. kiiensis larvae. Tests were conducted using three commercial Bti formulations (oil miscible suspension, 1,200 ITU/mL; wettable power, 1,200 ITU/mg; technical material, 5,000 ITU/mg) of Bti. The toxicity of Bti formulations to third and fourth instar C. kiiensis larvae was in decreasing order of technical material, oil miscible suspension, and wettable powder, based on the 12 and 24 hour LC50 values. Increasing larval densities (from 10 to 30 per bioassay cup) increased the LC50 values for fourth instar C. kiiensis larvae. The LC50 values for fourth instar larvae reared in sand substrate were higher than those from soil substrate, and autoclaved substrates significantly increased the LC50 values. The technical material of Bti at 12 and 24 hours responded similarly to changes in temperature between 30° C and 15° C, but the LC50 values at a range of tested temperatures showed distinct differences in time points.

  9. Susceptibility of Aedes aegypti larvae to temephos and Bacillus thuringiensis var israelensis in integrated control Susceptibilidade de larvas de Aedes aegypti ao tratamento integrado com temephos e Bacillus thuringiensis var israelensis

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    Carlos Fernando S. de Andrande

    1991-06-01

    Full Text Available The susceptibility of field collected Aedes aegypti larvae was evaluated in terms of median lethal time (LT50 and final mortality, when treated with temephos, Bacillus thuringiensis var israelensis as well as mixtures of these two agents. Third instar larvae were shown to be more susceptible than early and late fourth instar ones to the entomopathogen. Survival of some individuals when exposed to temephos suggest possible resistance. Temporal synergism in early fourth instar larvae was detected when they were exposed to mixtures of Bti-temephos. The possibility of this integrated treatment is commented on.A susceptibilidade de larvas de Aedes aegypti coletadas no campo foi avaliada em termos do tempo letal mediano (TL50 e da mortalidade final, quando tratadas com temephos, Bacillus thuringiensis var israelensis ou misturas desses dois agentes. As larvas de terceiro estádio mostraram-se mais suceptíveis ao patógeno do que aquelas no início ou no fim do quarto estádio. A sobrevivência de alguns indivíduos aos tratamentos com temephos permite sugerir a possibilidade de resistência. Foi detectada a existência de sinergismo temporal, quando larvas no início do quarto estádio foram tratadas com as misturas do Bti com o temephos. A possibilidade do tratamento integrado é comentada.

  10. Persistence of Toxic Activity of Fermentation Extracts from Bacillus thuringiensis var. israelensis after More Than Three Decades of Storage

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    Luis Jesús Galán-Wong

    2017-01-01

    Full Text Available This study was carried out to determine the persistence of toxicity of fermentation extracts of Bacillus thuringiensis var. israelensis after more than three decades of storage. For this purpose, a population of Aedes aegypti was established. The mortality rate of 20 spore-crystal extracts purified using the acetone-lactose coprecipitation method was measured and evaluated by bioassays according to a modified WHO protocol. The extracts with the highest mortality rate were determined in triplicate by their LD50 and LD98. All extracts showed toxicity at the highest tested dose (1000 ppm and some, such as strains 3260 and 3501, still killed larvae at doses as low as 0.01 ppm. These data are surprising because no study on the activity of B. thuringiensis toxic proteins after such a long storage time has been reported.

  11. [Experimental observation of toxic effect of Bacillus thuringiensis var. israelensis against Aedes, Culex and Anopheles larvae].

    Science.gov (United States)

    Li, Ju-Lin; Zhu, Guo-Ding; Zhou, Hua-Yun; Tang, Jian-Xia; Cao, Jun

    2014-02-01

    To evaluate the toxic effect of Bacillus thuringiensis var. israelensis (Bti) wettable powder against Aedes, Culex and Anopheles larvae. The biological assay was applied to test the lethal concentration of 50% (LC50) of Bti wettable powder against Aedes, Culex and Anopheles larvae. The LC50(s) of Bti wettable powder against Aedes albopictus, Culex pipiens pallens and Anopheles sinensis larvae were 0.104, 0.160 microg/ml and 0.324 microg/ml, respectively; its biological potencies against them were 0.125, 0.192 IU/ml and 0.389 IU/ml, respectively. The LC50(s) of continuous contact of Bti wettable powder with An. sinensis stage III larvae for 1, 2 d and 3 d were 0.324, 0.092 microg/ml and 0.032 microg/ml, respectively, and its biological potencies were 0.389, 0.110 IU/ml and 0.038 IU/ml, respectively. The LC50(s) of the bacteria against An. sinensis stage I , II, III, IV were 0.024, 0.137, 0.324 microg/ml and 0.450 microg/ml, respectively, and the biological potencies were 0.029, 0.164, 0.389 IU/ml and 0.540 IU/ml, respectively. Bti wettable powder has a good toxicity to Aedes, Culex and Anopheles larvae, especially for the latter two. It is better to apply the bacteria at the early stage of mosquito larvae.

  12. Production of wetland Chironomidae (Diptera) and the effects of using Bacillus thuringiensis israelensis for mosquito control.

    Science.gov (United States)

    Lundström, J O; Schäfer, M L; Petersson, E; Persson Vinnersten, T Z; Landin, J; Brodin, Y

    2010-02-01

    Massive mosquito nuisance problems, caused by the flood-water mosquito Aedes sticticus, occur after floods in the flood plains of the River Dalälven, central Sweden. Since 2002, the biological mosquito larvicide Bacillus thuringiensis var. israelensis (Bti) has been used to control these mosquitoes. Here, we report results from the first six years of monitoring Chironomidae, the most susceptible non-target organisms, in three wetlands with Bti-treatment against mosquitoes and in three wetlands without treatment. Emergence traps were used for continuous insect sampling from May to September each year, 2002-2007, and were emptied once a week. A total of 21,394 chironomids of 135 species were collected, and the subfamily Orthocladiinae dominated the fauna followed by Chironominae and Tanypodinae. The annual chironomid production in the wetlands was low, with an average of 1917 individuals per m(2), and 42 g ash-free dry weight per m(2). We found no reduced production of chironomids at neither family, nor subfamily level, in Bti-treated as compared to untreated wetlands. This is the first long-term follow-up study of the possible effects of Bti-based mosquito larval control on chironomid species production. In the short-term view, one species had higher production in treated areas. In the long-term view, four species had higher and one species had lower production in treated areas. We conclude that the Bti-based control of flood-water mosquitoes does not cause any major direct negative effects on chironomid production, and therefore does not seem to induce any risk for indirect negative effects on birds, bats or any other predators feeding on chironomids.

  13. Fate of Bacillus thuringiensis subsp. israelensis in the Field: Evidence for Spore Recycling and Differential Persistence of Toxins in Leaf Litter

    Science.gov (United States)

    Alessi, Mattia; Veyrenc, Sylvie; Périgon, Sophie; David, Jean-Philippe; Reynaud, Stéphane; Després, Laurence

    2012-01-01

    Bacillus thuringiensis subsp. israelensis is a bioinsecticide increasingly used worldwide for mosquito control. Despite its apparent low level of persistence in the field due to the rapid loss of its insecticidal activity, an increasing number of studies suggested that the recycling of B. thuringiensis subsp. israelensis can occur under specific, unknown conditions. Decaying leaf litters sampled in mosquito breeding sites in the French Rhône-Alpes region several months after a treatment were shown to exhibit a high level of larval toxicity and contained large amounts of spores. In the present article, we show that the high concentration of toxins found in these litters is consistent with spore recycling in the field, which gave rise to the production of new crystal toxins. Furthermore, in these toxic leaf litter samples, Cry4Aa and Cry4Ba toxins became the major toxins instead of Cyt1Aa in the commercial mixture. In a microcosm experiment performed in the laboratory, we also demonstrated that the toxins, when added in their crystal form to nontoxic leaf litter, exhibited patterns of differential persistence consistent with the proportions of toxins observed in the field-collected toxic leaf litter samples (Cry4 > Cry11 > Cyt). These results give strong evidence that B. thuringiensis subsp. israelensis recycled in specific breeding sites containing leaf litters, and one would be justified in asking whether mosquitoes can become resistant when exposed to field-persistent B. thuringiensis subsp. israelensis for several generations. PMID:23001669

  14. A differentially displayed mRNA related to restistance to Bacillus thuringiensis israelensis of Aedes albopictus selected in vitro-activated CYT1AA6

    Czech Academy of Sciences Publication Activity Database

    Zhang, L.; Zhang, Q.; Huang, E.; Li, M.; Huang, T.; Xu, L.; Wu, Ch.; Guan, X.; Gelbič, Ivan

    2012-01-01

    Roč. 28, č. 4 (2012), s. 327-329 ISSN 8756-971X Institutional support: RVO:60077344 Keywords : Bacillus thuringiensis israelensis * resistence * Aedes albopictus Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.755, year: 2012 http://www.bioone.org/doi/pdf/10.2987/12-6263R.1

  15. Combined effect of seaweed (Sargassum wightii) and Bacillus thuringiensis var. israelensis on the coastal mosquito,Anopheles sundaicus, in Tamil Nadu, India

    Science.gov (United States)

    Studies were made of the extract of Sargassum wightii combined with Bacillus thuringiensis var. israelensis (Bti) for control of the malaria vector Anopheles sundaicus. Treatment of mosquito larvae with 0.001% S. wightii extract indicated median lethal concentrations (LC50) of 88, 73, 134, 156, and...

  16. [Effect of Bacillus thuringiensis var. israelensis (Bti) on detoxification enzyme activity of larvae of Culex pipiens pallens and Aedes aegypti].

    Science.gov (United States)

    Han, Guang-jie; Li, Chuan-ming; Sun, Jun; Liu, Qin; Zhao, Song; Qi, Jian-hang; Xu, Jian

    2015-08-01

    To investigate the effect of Bacillus thuringiensis var. israelensis (Bti) on the activities of three detoxification enzymes of Culex pipiens pallens and Aedes aegypti larvae. The activities of glutathione transferase, acetyl cholinesterase and carboxyl esterase, were detected after two kinds of mosquito larvae were treated by Bti at different time and concentrations. The activities of three detoxification enzymes of the two kinds of mosquito larvae were influenced by Bti treatment. The activity of glutathione transferase was increased after the Bti treatment, but declined significantly and inhibited at a low level sustainably. The activity of carboxyl esterase was increased after the Bti treatment, but recovered to normal level quickly. Acetyl cholinesterase was affected slightly by the Bti treatment, shortly inhibited in the first time and then recovered. The active effects of the three detoxification enzymes were positively related to the concentration of Bti. The enzyme activities of glutathione transferase, acetyl cholinesterase and carboxyl esterase could be affected by Bti significantly.

  17. PENGARUH BEBERAPA DOSIS BACILLUS THURINGIENSIS VAR ISRAELENSIS SEROTYPE H14 TERHADAP LARVA AEDES AEGYPTI DI KALIMANTAN BARAT

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    Dian Perwitasari

    2016-03-01

    Full Text Available One of the dengue control efforts is the use  of Bacillus thuringiensis in order to reduce the dengue vector of Aedes aegypti through its larvas. This was an experimental research using gram-positive bacteria B. thuringiensis var israelensis (Bactivec serotype H-14 which was applied with several concentrations (0.02 ml, 0.01 ml and 0.007 ml in 246 ml of water that has been filled with 25 larvas of the 3rd or 4th instars. Larvas were taken from the area of ​​West Kalimantan. Data were analyzed using a completely randomized design to examine the percentage of larval mortality within 3 hours, 9 hours and over 12 hours. The results showed that the concentration of 0,02 bactivec caused 89%  larval mortality, and  concentrations of 0,01 and 0,007 caused 88% and 87% larval mortality, respectively within the 9 hours exposure time. It can be concluded that the use of 0,07 ml of bactivec  is still effective to  control  Aedes aegypti larvae. To determine  the negative of  the use of bactivec,  further studies  are needed.  

  18. 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).

  19. Isolation and purification of Bacillus thuringiensis var. israelensis IМV В-7465 peptidase with specificity toward elastin and collagen.

    Science.gov (United States)

    Nidialkova, N A; Varbanets, L D; Chernyshenko, V O

    2016-01-01

    Peptidase of Bacillus thuringiensis var. israelensis IМV В-7465 was isolated from culture supernatant using consecutive fractionations by an ammonium sulphate (60% saturation), ion-exchange chromatography and gel-filtration on the TSK-gels Toyoperl HW-55 and DEAE 650(M). Specific elastase (442 U∙mg of protein-1) and collagenase (212.7 U∙mg of protein-1) activities of the purified enzyme preparation were 8.0- and 6.1-fold, respectively higher than ones of the culture supernatant. Peptidase yields were 33.5% for elastase activity and 30.1% for collagenase activity. It was established that the enzyme is serine metal-dependent alkaline peptidase with Mr about 37 kDa. Maximal hydrolysis of elastin and collagen occurs at the optimum pH 8.0 and t° – 40 and 50 °С, respectively. The purified preparation has high stability at pH in the range of 7.0 to 10.0 and 40-50 °С.

  20. Solid-phase extraction of copper, iron and zinc ions on Bacillus thuringiensis israelensis loaded on Dowex optipore V-493

    International Nuclear Information System (INIS)

    Tuzen, Mustafa; Melek, Esra; Soylak, Mustafa

    2008-01-01

    Bacillus thuringiensis israelensis loaded on Dowex optipore V-493 as new adsorbent for the separation-preconcentration of heavy metal ions has been proposed. The analytical conditions for the quantitative recoveries of copper(II), iron(III) and zinc(II) including pH, amounts of adsorbent, sample volume, etc. were investigated. The influences of alkaline and earth alkaline ions were also reported. The recovery values for the analytes are generally higher than 95%. The preconcentration factor was 37. The limit of detections of the analyte ions (k = 3, N = 21) were 1.14 μg L -1 for copper, 2.01 μg L -1 for iron and 0.14 μg L -1 for zinc. The relative standard deviations of the determinations were found to be lower than 9%. The procedure was validated by analyzing copper, iron and zinc contents in two certified reference materials, NRCC-SLRS-4 Riverine water and NIST SRM 1515 Apple leaves. Agreements between the obtained results and the certified values were achieved. The developed preconcentration method was applied in the flame atomic absorption spectrometric determination of copper, iron and zinc in several samples including a multivitamin-multimineral tablet, dialysis solutions, natural waters and some food samples

  1. Solid-phase extraction of copper, iron and zinc ions on Bacillus thuringiensis israelensis loaded on Dowex optipore V-493

    Energy Technology Data Exchange (ETDEWEB)

    Tuzen, Mustafa; Melek, Esra [Gaziosmanpasa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey); Soylak, Mustafa [Erciyes University, Faculty of Science and Arts, Chemistry Department, 38039 Kayseri (Turkey)], E-mail: msoylak@gmail.com

    2008-11-30

    Bacillus thuringiensis israelensis loaded on Dowex optipore V-493 as new adsorbent for the separation-preconcentration of heavy metal ions has been proposed. The analytical conditions for the quantitative recoveries of copper(II), iron(III) and zinc(II) including pH, amounts of adsorbent, sample volume, etc. were investigated. The influences of alkaline and earth alkaline ions were also reported. The recovery values for the analytes are generally higher than 95%. The preconcentration factor was 37. The limit of detections of the analyte ions (k = 3, N = 21) were 1.14 {mu}g L{sup -1} for copper, 2.01 {mu}g L{sup -1} for iron and 0.14 {mu}g L{sup -1} for zinc. The relative standard deviations of the determinations were found to be lower than 9%. The procedure was validated by analyzing copper, iron and zinc contents in two certified reference materials, NRCC-SLRS-4 Riverine water and NIST SRM 1515 Apple leaves. Agreements between the obtained results and the certified values were achieved. The developed preconcentration method was applied in the flame atomic absorption spectrometric determination of copper, iron and zinc in several samples including a multivitamin-multimineral tablet, dialysis solutions, natural waters and some food samples.

  2. Fly ash based Bacillus thuringiensis var. israelensis formulation for use against Culex quinquefasciatus, the vector of filariasis in natural ecosystems.

    Science.gov (United States)

    Tamilselvan, S; Jambulingam, P; Manoharan, V; Shanmugasundaram, R; Vivekanandan, G; Manonmani, A M

    2015-09-01

    Fly ash is produced in huge quantities by the various thermal power stations in India. This thermal waste has been employed as a carrier material in the preparation of a biopesticidal water dispersible powder (WDP) formulation for use against mosquitoes. In the present investigation, this newly developed fly ash based WDP formulation was evaluated in natural breeding habitats of mosquito. Fly ash based WDP formulation of Bacillus thuringiensis var. israelensis (VCRC B17) was evaluated for its efficacy and residual activity in aquatic habitats supporting breeding of Culex quinquefasciatus, the vector of lymphatic filariasis in Neyveli Township, Neyveli Lignite Corporation, India for a period of one month. At an application rate of 10 kg/ha, the WDP was effective for five days regardless of the habitat, and provided 80-100% reduction in larval abundance of Cx. quinquefasciatus. The study indicates that for continued control of immature density and prevention of adult emergence, a weekly application of this formulation is necessary. This study also showed that fly ash based formulations can be used for immediate control of mosquitoes in different types of habitats and has also brought out a new avenue for the utilization of coal ash.

  3. Use of Bacillus thuringiensis israelensis in integrated vector control of Aedes sp. in Sri Lanka: a prospective controlled effectiveness study.

    Science.gov (United States)

    Tissera, H A; Samaraweera, P C; Jayamanne, B D W; Janaki, M D S; U Chulasiri, M P P; Rodrigo, C; Fernando, S D

    2018-02-01

    The annual incidence of dengue has been increasing over the last few years in Sri Lanka with seasonal epidemics. Biological control of the vector has not been part of the integrated vector control implemented by the public health authorities of Sri Lanka so far. This pilot study assessed the effectiveness of using Bacillus thuringiensis israelensis (Bti) spray to control the Aedes mosquito vector population density. Prospective controlled effectiveness study in three administrative divisions of Colombo. Study areas were selected from urban, semiurban and rural administrative divisions within the district, and they were compared with two matching controls from the same division. Test areas received three cycles of Bti spraying 1 month apart. Control areas were not sprayed with Bti. Ovitrap and larval indices were calculated at baseline and 2 weeks after each spray cycle. There was a significant improvement in the adult vector population (ovitrap index) in the test areas after three spray cycles, but this effect had disappeared after 8 weeks (no residual effect). There was no consistent positive impact on larval indices (premise, container and Breteau indices) after each spray cycle. Bti might have a moderate impact on adult vector populations mediated via transient reductions in larval populations. However, this effect is not sustained probably due to rapid re-infestation. Bti spray, if implemented, can only play a supplementary role to other vector control methods. © 2017 John Wiley & Sons Ltd.

  4. Monitoring resistance to Bacillus thuringiensis subsp. israelensis in the field by performing bioassays with each Cry toxin separately

    Directory of Open Access Journals (Sweden)

    Guillaume Tetreau

    2013-11-01

    Full Text Available Bacillus thuringiensis subsp. israelensis (Bti is increasingly used worldwide for mosquito control and is the only larvicide used in the French Rhône-Alpes region since decades. The artificial selection of mosquitoes with field-persistent Bti collected in breeding sites from this region led to a moderate level of resistance to Bti, but to relatively high levels of resistance to individual Bti Cry toxins. Based on this observation, we developed a bioassay procedure using each Bti Cry toxin separately to detect cryptic Bti-resistance evolving in field mosquito populations. Although no resistance to Bti was detected in none of the three mosquito species tested (Aedes rusticus, Aedes sticticus and Aedes vexans, an increased tolerance to Cry4Aa (3.5-fold and Cry11Aa toxins (8-fold was found in one Ae. sticticus population compared to other populations of the same species, suggesting that resistance to Bti may be arising in this population. This study confirms previous works showing a lack of Bti resistance in field mosquito populations treated for decades with this bioinsecticide. It also provides a first panorama of their susceptibility status to individual Bti Cry toxins. In combination with bioassays with Bti, bioassays with separate Cry toxins allow a more sensitive monitoring of Bti-resistance in the field.

  5. Culex Mosquitoes (Diptera: Culicidae) Egg Laying in Traps Loaded With Bacillus thuringiensis Variety israelensis and Baited With Skatole

    Science.gov (United States)

    BARBOSA, ROSÂNGELA M. R.; REGIS, LÊDA; VASCONCELOS, ROBERTO; LEAL, WALTER S.

    2010-01-01

    The Southern house mosquito, Culex quinquefasciatus, is an important human health pest as a vector of several pathogens, including agents of lymphatic filariasis and arboviruses like West Nile virus. We conducted preliminary experiments in Recife, Brazil, to explore applications of Culex oviposition attractants in combination with Bacillus thuringiensis variety israelensis (Bti) in an attract- and-kill approach. Simple, cost-effective oviposition traps, BR-OVT, loaded with Bti and baited with or without attractant, were deployed in 10 homes for 30 d in 2 consecutive yr. Significantly higher numbers of egg rafts were deposited in traps baited with skatole or infusion than the control water traps. In the first year, 2006, significantly higher numbers of eggs were deposited in infusion-baited traps, particularly in the first 15 d of the experiment, than in skatole traps, but in the following year no significant difference was observed between synthetic and natural attractants. The tests strongly demonstrate that skatole or infusion can be used to enhance the number of egg rafts deposited on Bti-treated oviposition traps. PMID:20496581

  6. Isolation and purification of Bacillus thuringiensis var. israelensis IМV В-7465 peptidase with specificity toward elastin and collagen

    Directory of Open Access Journals (Sweden)

    N. А. Nidialkova

    2016-06-01

    Full Text Available Peptidase of Bacillus thuringiensis var. israelensis IМV В-7465 was isolated from culture supernatant using consecutive fractionations by an ammonium sulphate (60% saturation, ion-exchange chromatography and gel-filtration on the TSK-gels Toyoperl HW-55 and DEAE 650(M. Specific elastase (442 U∙mg of protein-1 and collagenase (212.7 U∙mg of protein-1 activities of the purified enzyme preparation were 8.0- and 6.1-fold, respectively higher than ones of the culture supernatant. Peptidase yields were 33.5% for elastase activity and 30.1% for collagenase activity. It was established that the enzyme is serine metal-dependent alkaline peptidase with Mr about 37 kDa. Maximal hydrolysis of elastin and collagen occurs at the optimum pH 8.0 and t° – 40 and 50 °С, respectively. The purified preparation has high stability at pH in the range of 7.0 to 10.0 and 40-50 °С.

  7. Mosquito biolarvicide production by sequential fermentation with dual strains of Bacillus thuringiensis subsp. israelensis and Bacillus sphaericus using sewage sludge.

    Science.gov (United States)

    Zhuang, Li; Zhou, Shungui; Wang, Yueqiang; Chang, Min

    2011-01-01

    This study demonstrated the bioconversion of sewage sludge into a composite biolarvicide for mosquito control based on sequential fermentation with dual strains of Bacillus thuringiensis subsp. israelensis (Bti) and Bacillus sphaericus (Bs). Results showed that sewage sludge was a suitable fermentation substrate for supporting growth, sporulation and mosquitocidal proteins synthesis by Bti and Bs. Through sequential fermentation with dual strains, a 10-L bench-scale fermentor was capable of producing Bti and Bs at a cell concentration of 2.1×10(9) and 6.8×10(8) CFU/mL, respectively. Such sequential fermentation can save half of raw materials and energy consumption comparing with the sludge fermentation with single strain. The toxic activity and persistence of the composite biolarvicide against mosquito larvae in the polluted waters were enhanced by the increased toxin complexity and synergistic interactions. This study, for the first time, validates the technical feasibility of using sewage sludge to produce a cost-effective composite biolarvicide based on Bti and Bs. Copyright © 2010 Elsevier Ltd. All rights reserved.

  8. Operational Evaluation Of Vectomax® WSP (Bacillus thuringiensis Subsp. israelensis+Bacillus sphaericus) Against Larval Culex pipiens in Septic Tanks (1).

    Science.gov (United States)

    Cetin, Huseyin; Oz, Emre; Yanikoglu, Atila; Cilek, James E

    2015-06-01

    The residual effectiveness of VectoMax® WSP (a water-soluble pouch formulation containing a combination of Bacillus thuringiensis subsp. israelensis strain AM65-52 and B. sphaericus strain ABTS 1743) when applied to septic tanks against 3rd- and 4th-stage larvae of Culex pipiens L. was evaluated in this study. This formulation was evaluated at operational application rates of 1 pouch (10 g) and 2 pouches (20 g) per septic tank. Both application rates resulted in >96% control of larvae for 24 days. Operationally, VectoMax WSP has proven to be a useful tool for the nonchemical control of Culex species in septic tank environments.

  9. Mapping of residues of fibrinogen cleaved by protease II of Bacillus thuringiensis var. israelensis IMV B-7465

    Directory of Open Access Journals (Sweden)

    E. M. Stohniy

    2016-04-01

    Full Text Available The limited proteolysis of macromolecules allows obtaining the fragments that preserve the structure and functional properties of the whole molecule and could be used in the study of proteins structure and function. Proteases targeted to fibrinogen and fibrin are of interest as the tool for obtaining of functionally active fragments of fibrin(ogen and for the direct defibrination in vivo. That is why the aim of the present work was to study the proteolytic action of Protease II (PII purified from Bacillus thuringiensis var. israelensis IMV B-7465 on fibrinogen. Hydrolysis products of fibrinogen by PII were analysed by SDS-PAGE under reducing conditions with further immunoprobing using the mouse monoclonal 1-5A (anti-Aα509-610 and ІІ-5С (anti-Aα20-78 antibodies. It was shown that PII cleaved preferentially the Aα-chain of fibrinogen splitting off the peptide with apparent molecular weight of 10 kDa that corresponded the C-terminal part of Aα-chain of fibrinogen molecule. MALDI-TOF analysis of hydrolysis of fibrinogen was performed using a Voyager-DE. Results analyzed by Data Explorer 4.0.0.0 allowed to detect the main peak occurring at mass/charge (M/Z ratio of 11 441 Da. According to “Peptide Mass Calculator” this peptide corresponded to fragment Аα505-610 of fibrinogen molecule. The result showed that PII cleaves the peptide bond AαAsp-Thr-Ala504-Ser505. Thus, PII can be used for the obtaining of unique fragments of fibrinogen molecule. As far as αC-domain contains numerous sites of fibrin intermolecular interactions we can consider PII as a prospective agent for their study and for the defibrination.

  10. Dynamics of Bacillus thuringiensis var. israelensis and Lysinibacillus sphaericus spores in urban catch basins after simultaneous application against mosquito larvae.

    Science.gov (United States)

    Guidi, Valeria; Lehner, Angelika; Lüthy, Peter; Tonolla, Mauro

    2013-01-01

    Bacillus thuringiensis var. israelensis (Bti) and Lysinibacillus sphaericus (Lsph) are extensively used in mosquito control programs. These biocides are the active ingredients of a commercial larvicide. Quantitative data on the fate of both Bti and Lsph applied together for the control of mosquitoes in urban drainage structures such as catch basins are lacking. We evaluated the dynamics and persistence of Bti and Lsph spores released through their concomitant application in urban catch basins in southern Switzerland. Detection and quantification of spores over time in water and sludge samples from catch basins were carried out using quantitative real-time PCR targeting both cry4A and cry4B toxin genes for Bti and the binA gene for Lsph. After treatment, Bti and Lsph spores attained concentrations of 3.76 (± 0.08) and 4.13 (± 0.09) log ml(-1) in water, then decreased progressively over time, reaching baseline values. For both Bti and Lsph, spore levels in the order of 10(5) g(-1) were observed in the bottom sludge two days after the treatment and remained constant for the whole test period (275 days). Indigenous Lsph strains were isolated from previously untreated catch basins. A selection of those was genotyped using pulsed field gel electrophoresis of SmaI-digested chromosomal DNA, revealing that a subset of isolates were members of the clonal population of strain 2362. No safety issues related to the use of this biopesticide in the environment have been observed during this study, because no significant increase in the number of spores was seen during the long observation period. The isolation of native Lysinibacillus sphaericus strains belonging to the same clonal population as strain 2362 from catch basins never treated with Lsph-based products indicates that the use of a combination of Bti and Lsph for the control of mosquitoes does not introduce non-indigenous microorganisms in this area.

  11. Mortality Patterns of Simulium vittatum Larvae (Diptera: Simuliidae) Following Exposure to Insecticidal Proteins Produced by Bacillus thuringiensis var. israelensis.

    Science.gov (United States)

    Iburg, Joseph P; Gray, Elmer W; Noblet, Raymond

    2015-03-01

    Products containing insecticidal crystalline proteins (ICPs) produced by Bacillus thuringiensis var. israelensis (Bti ICPs) are used to suppress vector and nuisance populations of black flies. The efficacy of an application of these products is often determined by a posttreatment evaluation of larval mortality. Larvae are typically removed from the substrate at some point in time after application of the product and mortality is determined. The time necessary for the effects of Bti ICPs to cause morality in exposed larvae can vary, and there is little consensus on how long operators should wait before evaluating larval mortality. This study was conducted to provide more information to larvicide applicators when performing posttreatment evaluations. Simulium vittatum larvae were exposed to Bti ICPs under controlled conditions and the mortality was monitored over time. Larvae exposed to operational concentrations of ICPs exhibited maximum mortality, approximately 87%, after 4 h. Exposure of larvae to 1/3 of that concentration resulted in similar mortality; however, the maximum mortality was not reached until 8 h postexposure. Additional experiments revealed that maximum mortality and time to maximum mortality can also be affected by components in the larval medium. Larval mortality was compared between larvae exposed to Bti ICPs in moderately hard water, medium containing 50 parts per million (ppm) of kaolinite, and medium containing 50 ppm of cellulose. The clay material had no significant effect on larval mortality or time to achieve maximum mortality. When cellulose was present in the medium, the time to maximum mortality was increased 50% and overall mortality was reduced by more than 40%.

  12. Tolerance to individual and joint effects of arsenic and Bacillus thuringiensis subsp. israelensis or Lysinibacillus sphaericus in Culex mosquitoes.

    Science.gov (United States)

    Mogren, Christina L; Walton, William E; Trumble, John T

    2014-08-01

    Arsenic contamination of global water supplies has come to the forefront in policy decisions in recent decades. However, the effects of arsenic on lower trophic levels of insects inhabiting contaminated ecosystems are not well understood. One approach to document both acute and sublethal effects of toxicants like arsenic is to assay them in combination with microbial pathogens to evaluate shifts in survival curves of the test organisms. Larvae of Culex quinquefasciatus and Culex tarsalis were reared in water containing 0 or 1 000 μg/L of arsenate or arsenite. Fourth instars were then exposed to a range of doses of Bacillus thuringiensis subsp. israelensis (Bti) or Lysinibacillus sphaericus (Ls), with shifts in lethal concentrations determined. Arsenic accumulation in 4th instars was also quantified, and a relative growth index (RGI) calculated for the treatments and compared to controls. Larvae of both species accumulated between 4 447 ± 169 ng As/g and 6 983 ± 367 ng As/g, though RGI values indicated accumulation did not affect growth and development. In all cases, the LC50 's and LC90 's of Cx. quinquefasciatus exposed jointly with arsenic and Bti/Ls were higher than Cx. tarsalis. Cx. tarsalis reared in arsenite showed a significant reduction in their Bti LC90 values compared to the control, indicating a sublethal effect of Bti. When exposed jointly with Ls, arsenite was more toxic than arsenate in Cx. tarsalis. Overall, these results indicate tolerance of these Culex species to arsenic exposures, and why this may occur is discussed. © 2013 Institute of Zoology, Chinese Academy of Sciences.

  13. Dynamics of Bacillus thuringiensis var. israelensis and Lysinibacillus sphaericus spores in urban catch basins after simultaneous application against mosquito larvae.

    Directory of Open Access Journals (Sweden)

    Valeria Guidi

    Full Text Available Bacillus thuringiensis var. israelensis (Bti and Lysinibacillus sphaericus (Lsph are extensively used in mosquito control programs. These biocides are the active ingredients of a commercial larvicide. Quantitative data on the fate of both Bti and Lsph applied together for the control of mosquitoes in urban drainage structures such as catch basins are lacking. We evaluated the dynamics and persistence of Bti and Lsph spores released through their concomitant application in urban catch basins in southern Switzerland. Detection and quantification of spores over time in water and sludge samples from catch basins were carried out using quantitative real-time PCR targeting both cry4A and cry4B toxin genes for Bti and the binA gene for Lsph. After treatment, Bti and Lsph spores attained concentrations of 3.76 (± 0.08 and 4.13 (± 0.09 log ml(-1 in water, then decreased progressively over time, reaching baseline values. For both Bti and Lsph, spore levels in the order of 10(5 g(-1 were observed in the bottom sludge two days after the treatment and remained constant for the whole test period (275 days. Indigenous Lsph strains were isolated from previously untreated catch basins. A selection of those was genotyped using pulsed field gel electrophoresis of SmaI-digested chromosomal DNA, revealing that a subset of isolates were members of the clonal population of strain 2362. No safety issues related to the use of this biopesticide in the environment have been observed during this study, because no significant increase in the number of spores was seen during the long observation period. The isolation of native Lysinibacillus sphaericus strains belonging to the same clonal population as strain 2362 from catch basins never treated with Lsph-based products indicates that the use of a combination of Bti and Lsph for the control of mosquitoes does not introduce non-indigenous microorganisms in this area.

  14. Histopathological effects of cypermethrin and Bacillus thuringiensis var. israelensis on midgut of Chironomus calligraphus larvae (Diptera: Chironomidae).

    Science.gov (United States)

    Lavarías, Sabrina; Arrighetti, Florencia; Siri, Augusto

    2017-06-01

    Pesticides are extensively used for the control of agricultural pests and disease vectors, but they also affect non-target organisms. Cypermethrin (CYP) is a synthetic pyrethroid used worldwide. Otherwise, bioinsecticides like Bacillus thuringiensis var. israelensis (Bti) have received great attention as an environmentally benign and desirable alternative. In order to evaluate the toxicity of those pesticides, Chironomus calligraphus was selected due to its high sensitivity to some toxicants. Third and fourth instars larvae were exposed to serial dilutions of CYP and Bti to determine LC 50 values. In order to evaluate the potentially histopathological alterations as biomarkers, after 96-h of exposure, live larvae were fixed for histological analysis of the mid region of digestive tract. The 96-h LC 50 values were 0.52 and 1.506μg/L for CYP and Bti, respectively. Midgut histological structure of the control group showed a single layer of cubical cells with microvilli in their apical surface and a big central nucleus. The midgut epithelium of larvae exposed to a low concentration of CYP (0.037μg/L) showed secretion activity and vacuolization while at high concentration (0.3μg/L) cells showed a greater disorganization and a more developed fat body. On the other hand, Bti caused progressive histological damage in this tissue. Chironomus calligraphus is sensitive to Bti and CYP toxicity like other Chironomus species. The histopathological alterations could be a valuable tool to assess toxicity mechanism of different pesticides. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. 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.

  16. [Susceptibility of populations of Simulium (Chirostilbia) pertinax Kollar, 1832 (Culicomorpha, Simuliidae) to eemephos and to Bacillus thuringiensis var. israelensis-based formulation].

    Science.gov (United States)

    de Andrade, C F; Castello Branco Júnior, A

    1991-10-01

    The use of wooden troughs on stream beds, artificially colonized by blackfly larvae, is proposed for larvicide evaluations. Mortality was recorded 3 or 4 hours after treatment. Larval susceptibility was also evaluated utilizing the LT50 criterion. In there field assays Simulium (C.) pertinax populations from the litoral of S. Paulo and Rio de Janeiro States were shown to be resistant to temephos, even when subjected to high concentrations. Vectobac 12 AS, a Bacillus thuringiensis var. israelensis product, was shown to be more potent against late instar larvae and efficient in concentrations higher than 7,200 ITU/l (10 min). The LT50 to 3,744 ITU/l (10 min) was calculated as 70.9 min.

  17. Bacillus thuringiensis var. israelensis immobilized on Chromosorb 101: A new solid phase extractant for preconcentration of heavy metal ions in environmental samples

    International Nuclear Information System (INIS)

    Mendil, Durali; Tuzen, Mustafa; Usta, Canan; Soylak, Mustafa

    2008-01-01

    Bacillus thuringiensis var. israelensis immobilized on Chromosorb 101 that is a new solid phase extractor has been presented at this work for the preconcentration and separation of cadmium(II), lead(II), manganese(II), chromium(III), nickel(II) and cobalt(II) in environmental samples. The analytical parameters including pH of aqueous solutions, sample volume, eluent types, etc. were investigated for the quantitative recoveries of the analytes. The influences of the some metal ions as concomitant were investigated. Under the optimized conditions, the detection limits by 3σ for analyte ions were in the range of 0.37-2.85 μg L -1 . The accuracy of the developed procedure was confirmed by IAEA 336 Lichen and NIST SRM 1573a Tomato leaves certified reference materials. The method was also applied successfully to the determination of analytes in microwave digested red wine, rice and canned fish samples and sea water, spring water and urine samples

  18. Comparison of two commercial formulations of Bacillus thuringiensis var. israelensis for the control of Anopheles aquasalis (Diptera: Culicidae at three salt concentrations

    Directory of Open Access Journals (Sweden)

    Frances R Osborn

    2007-02-01

    Full Text Available Anopheles aquasalis larvae are salt water tolerant, preferring concentrations between 10 and 20 parts per thousand (ppt. The larvicidal efficacy of two formulations of Bacillus thuringiensis var. israelensis (Vectobac-12AS® and Bactivec®, was investigated against An. aquasalis at salinities of 0, 10, and 20 ppt. A probit analysis was used to calculate the lethal concentrations (LC50 and LC95 for each product at each salinity. The LC50 and LC95 were higher for Bactivec® than Vectobac-12AS®, and for Bactivec®, the LC50 and LC95 increased with salinity. Vectobac-12AS® should thus be preferred to Bactivec® for An. aquasalis control, especially in saline breeding habitats.

  19. Efficacy and efficiency of new Bacillus thuringiensis var. israelensis and Bacillus sphaericus formulations against Afrotropical anophelines in Western Kenya

    NARCIS (Netherlands)

    Fillinger, U.; Knols, B.G.J.; Becker, N.

    2002-01-01

    We evaluated the efficacy of new water-dispersible granular (WDG) formulations of Bacillus thuringienis var. israelensis (Bti; VectoBac?) and B. sphaericus (Bs; VectoLex?, Valent BioScience Corp., Illinois, USA) for the control of larval Anopheles gambiae sensu lato Giles mosquitoes in a

  20. Development of a Low Cost Bioprocess for Endotoxin Production by Bacillus thuringiensis var israelensis Intended for Biological Control of Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Carlos Ricardo Soccol

    2009-11-01

    Full Text Available Aedes aegypti is the vector of Dengue disease, responsible for 20,000 deaths/year worldwide. Bacillus thuringiensis var israelensis - Bti releases selective and effective toxins (crystal proteins against A. aegypti larvae. We present a low cost bioprocess for toxin production, accomplished by a selected Brazilian strain Bti (BR-LPB01 and employment of low cost substrates. Soybean meal and sugarcane molasses lead to high toxic effectiveness after 2L bioreactor fermentation (LD50=26ng/mL, near to the reference strain IPS82 (LD50=17.3 ng/mL. The pH ranged between 5.8 and 7.0 during the exponential growth period and between 7.0 and 8.4 during the stationary phase, with low activity. Thus, control of foam and pH 7.0 were started and proved to be crucial for high activity. It was verified that the fermentation could be discontinued after 20 hours, when the highest activity was present.A dengue é transmitida pelo Aedes aegypti, doença responsável por 20.000 mortes/ano no mundo. Bacillus thuringiensis var israelensis libera toxinas seletivas e eficazes (proteínas cristal contra larvas de A. aegypti. Propõe-se um bioprocesso de baixo custo para a produção da toxina, pelo emprego de uma cepa brasileira selecionada de Bti (BR-LPB01 e de substratos de baixo custo. Farelo de soja e melaço de cana levaram a eficácia tóxica alta após fermentação em biorreator 2L (DL50=26ng/mL, valor próximo a estirpe de referência IPS82 (DL50=17,3 ng/mL. O pH variou entre 5,8 e 7,0 durante o período de crescimento exponencial e entre 7,0 e 8,4 durante a fase estacionária, com baixa atividade larvicida. Assim, controles de espuma e de pH 7,0 foram iniciados e demonstraram serem cruciais para alta atividade. Verificou-se que a fermentação deve ser interrompida após vinte horas, quando se obtém a maior atividade.

  1. Susceptibilidade de populações de Simulium (Chirostilbia pertinax Kollar, 1832 (Culicomorpha, Simuliidae ao temephos e a um formulado à base de Bacillus thuringiensis var. israelensis Susceptibility of population of Simulium (Chirostilbia pertinax Kollar, 1832 (Culicomorpha, Simuliidae to temephos and Bacillus thuringiensis var. israelensis formulation

    Directory of Open Access Journals (Sweden)

    Carlos Fernando S. de Andrade

    1991-10-01

    Full Text Available O uso de pequenas calhas de madeira no leito de riachos, manualmente colonizadas com borrachudos, é proposto para avaliações da eficiência de larvicidas 3 ou 4 horas após as aplicações. A susceptibilidade larval também foi avaliada pelo critério de TL50. Em três ensaios no litoral do Estado de São Paulo e Rio de Janeiro, populações de Simulium (C. pertinax Kollar, 1832 mostraram-se resistentes ao temephos, mesmo em altas concentrações. Vectobac 12 AS, à base de Bacillus thuringiensis var. israelensis mostrou-se mais potente contra larvas dos últimos estádios e eficiente para controle em concentrações a partir de 7.200 UIP/1 (10 min.. O TL50para 3.744 UIP/1 (10 min. foi de 70,9 minutos.The use of wooden troughs on stream beds, artificially colonized by blackfly larvae, is proposed for larvicide evaluations. Mortality was recorded 3 or 4 hours after treatment. Larval susceptibility was also evaluated utilizing the LT50 criterion. In there field assays Simulium (C. pertinax populations from the litoral of S. Paulo and Rio de Janeiro States were shown to be resistant to temephos, even when subjected to high concentrations. Vectobac 12 AS, a Bacillus thuringiensis var. israelensis product, was shown to be more potent against late instar larvae and efficient in concentrations higher than 7,200 ITU/1 (10 min. The LT50 to 3,744 ITU/1 (10 min was calculated as 70.9 min.

  2. Comparison between diflubenzuron and a Bacillus thuringiensis israelensis- and Lysinibacillus sphaericus-based formulation for the control of mosquito larvae in urban catch basins in Switzerland.

    Science.gov (United States)

    Guidi, Valeria; Lüthy, Peter; Tonolla, Mauro

    2013-06-01

    A field test was conducted to evaluate a commercial biolarvicide based on Bacillus thuringiensis var. israelensis and Lysinibacillus sphaericus to control mosquitoes breeding in catch basins in southern Switzerland. The efficacy and residual activity of the microbial mosquito larvicide applied at the recommended rate of 10 g per catch basin was compared to the currently used larvicide diflubenzuron. Both products provided a very good control activity (> 97% of reduction) of late instars (3rd and 4th instars) and pupae for 4 wk. However, only the microbial formulation controlled immature stages during the whole period of the trial, with > 98% of larval reduction. A single application of the microbial larvicide applied at 10 g per catch basin significantly reduced the number of immature mosquitoes for at least 70 days. The quantity of rainfall in the 48-h period before each sampling and the water temperature did not influence the efficacy of the treatments. Under the environmental conditions encountered in southern Switzerland, the larvicide tested may be a valid alternative to diflubenzuron to control mosquitoes in urban catch basins. The long-lasting control by the microbial larvicide further reduces the number of treatments required to keep the population of mosquitoes at low levels.

  3. Evaluation of a commercial Bacillus thuringiensis var. israelensis formulation for the control of chironomid midge larvae (Diptera: Chironomidae) in establishing rice crops in south-eastern Australia.

    Science.gov (United States)

    Stevens, Mark M; Hughes, Peter A; Mo, Jianhua

    2013-01-01

    A commercial formulation of Bacillus thuringiensis var. israelensis (B.t.i.) was evaluated for its potential to control chironomid midge larvae in newly sown rice crops in south-eastern Australia. Two replicated small-plot field trials were conducted using product application rates of 0.5-6 kg/ha. In trial 1 application rates between 2 and 6 kg product/ha all significantly (Plarvae to species level from selected samples indicated that populations of Chironomus tepperi, the principal pest species that attacks the roots of rice seedlings, were reduced at all application rates; elimination of C. tepperi was achieved in trial 1 at an application rate of 2 kg/ha. Consistent with other studies, non-target Tanypodinae were not adversely affected by B.t.i., and in some treatments populations of Tanypodinae exceeded control levels by up to 73%. In the first trial, which was conducted under relatively high pest pressure, plant establishment was significantly (Plarvae in establishing rice crops where members of the Chironominae, the group most susceptible to B.t.i., are the principal species of concern. The high specificity of B.t.i. for nematoceran Diptera should lead to reduced impacts on non-target organisms. Copyright © 2012 Elsevier Inc. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    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.

  5. Sequence Analysis of Inducible Prophage phIS3501 Integrated into the Haemolysin II Gene of Bacillus thuringiensis var israelensis ATCC35646

    Directory of Open Access Journals (Sweden)

    Bouziane Moumen

    2012-01-01

    Full Text Available Diarrheic food poisoning by bacteria of the Bacillus cereus group is mostly due to several toxins encoded in the genomes. One of them, cytotoxin K, was recently identified as responsible for severe necrotic syndromes. Cytotoxin K is similar to a class of proteins encoded by genes usually annotated as haemolysin II (hlyII in the majority of genomes of the B. cereus group. The partially sequenced genome of Bacillus thuringiensis var israelensis ATCC35646 contains several potentially induced prophages, one of them integrated into the hlyII gene. We determined the complete sequence and established the genomic organization of this prophage-designated phIS3501. During induction of excision of this prophage with mitomycin C, intact hlyII gene is formed, thus providing to cells a genetic ability to synthesize the active toxin. Therefore, this prophage, upon its excision, can be implicated in the regulation of synthesis of the active toxin and thus in the virulence of bacterial host. A generality of selection for such systems in bacterial pathogens is indicated by the similarity of this genetic arrangement to that of Staphylococcus aureus  β-haemolysin.

  6. 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

  7. Fly ash based Bacillus thuringiensis var. israelensis formulation for use against Culex quinquefasciatus, the vector of filariasis in natural ecosystems

    OpenAIRE

    S Tamilselvan; P Jambulingam; V Manoharan; R Shanmugasundaram; G Vivekanandan; A M Manonmani

    2015-01-01

    Background & objectives: Fly ash is produced in huge quantities by the various thermal power stations in India. This thermal waste has been employed as a carrier material in the preparation of a biopesticidal water dispersible powder (WDP) formulation for use against mosquitoes. In the present investigation, this newly developed fly ash based WDP formulation was evaluated in natural breeding habitats of mosquito. Methods: Fly ash based WDP formulation of Bacillus thuringiensis var. israele...

  8. Use of Bacillus thuringiensis var israelensis as a viable option in an Integrated Malaria Vector Control Programme in the Kumasi Metropolis, Ghana.

    Science.gov (United States)

    Nartey, Rita; Owusu-Dabo, Ellis; Kruppa, Thomas; Baffour-Awuah, Sandra; Annan, Augustina; Oppong, Samuel; Becker, Norbert; Obiri-Danso, Kwasi

    2013-04-22

    Integrated Vector Control (IVC) remains the approach for managing the malaria-causing vector. The study investigated the contribution of Bacillus thuringiensis israelensis (Bti) in the control of malaria by targeting the larvae and also mapped and documented major breeding sites in the Kumasi metropolis, Ghana. Using a hand held GPS receiver unit, major breeding sites within the metropolis were mapped out during the larval survey. Mosquito larvae were then collected from the breeding sites and reared in an insectary to obtain an F1 generation for laboratory bioassays. The minimum effective dosage of Bti Water Dispersible Granular (WDG) formulation was determined by a series of bioassays. Based on the results obtained in the laboratory, the optimum effective dosage of Bti formulations against naturally occurring larvae of the indigenous mosquito species was determined through open field trials. A total of 33 breeding sites were identified and geo-referenced during the larval surveys with the majority of the breeding sites located in the Asokwa sub-metropolis, Kumasi, Ghana. A Bti (3,000 International Toxic Unit (ITU)/mg) concentration of 0.026 mg/l resulted in 50% mortality whilst a concentration of 0.136 mg/l resulted in 95% mortality. Results from the open field trials with Bti showed that a dosage of 0.2 kg/ha is as effective as 0.4 kg/ha in suppressing late instars and resulting pupae. This study reveals that Bti at a very low dosage of 0.2 kg/ha is highly effective against Anopheles larvae and therefore offers viable options for the management of vector mosquitoes. Further research is needed to extend this to the field in order to determine its ability to reduce malaria incidence.

  9. Evaluating Liquid and Granular Bacillus thuringiensis var. israelensis Broadcast Applications for Controlling Vectors of Dengue and Chikungunya Viruses in Artificial Containers and Tree Holes.

    Science.gov (United States)

    Harwood, James F; Farooq, Muhammad; Turnwall, Brent T; Richardson, Alec G

    2015-07-01

    The principal vectors of chikungunya and dengue viruses typically oviposit in water-filled artificial and natural containers, including tree holes. Despite the risk these and similar tree hole-inhabiting mosquitoes present to global public health, surprisingly few studies have been conducted to determine an efficient method of applying larvicides specifically to tree holes. The Stihl SR 450, a backpack sprayer commonly utilized during military and civilian vector control operations, may be suitable for controlling larval tree-hole mosquitoes, as it is capable of delivering broadcast applications of granular and liquid dispersible formulations of Bacillus thuringiensis var. israelensis (Bti) to a large area relatively quickly. We compared the application effectiveness of two granular (AllPro Sustain MGB and VectoBac GR) and two liquid (Aquabac XT and VectoBac WDG) formulations of Bti in containers placed on bare ground, placed beneath vegetative cover, and hung 1.5 or 3 m above the ground to simulate tree holes. Aedes aegypti (L.) larval mortality and Bti droplet and granule density data (when appropriate) were recorded for each formulation. Overall, granular formulations of Bti resulted in higher mortality rates in the simulated tree-hole habitats, whereas applications of granular and liquid formulations resulted in similar levels of larval mortality in containers placed on the ground in the open and beneath vegetation. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

  10. European common frog Rana temporaria (Anura: Ranidae) larvae show subcellular responses under field-relevant Bacillus thuringiensis var. israelensis (Bti) exposure levels.

    Science.gov (United States)

    Allgeier, Stefanie; Frombold, Bianca; Mingo, Valentin; Brühl, Carsten A

    2018-04-01

    Bacillus thuringiensis var. israelensis (Bti) is presumed to be an environmental friendly agent for the use in either health-related mosquito control or the reduction of nuisance associated with mosquitoes from seasonal wetlands. Amphibians inhabiting these valuable wetlands may be exposed to Bti products several times during their breeding season. Up until now, information regarding effects on the non-targeted group of amphibians has to be considered rather inconsistent. On this account, we evaluated how three repeated exposures to frequently used Bti formulations (VectoBac ® 12AS, VectoBac ® WG) in field-relevant rates affect European common frog (Rana temporaria) larvae. In a laboratory approach, we assessed potential effects with regard to enzymatic biomarkers (glutathione-S-transferase (GST), glutathione reductase (GR), acetylcholine esterase (AChE)), development, body condition and survival until the end of metamorphosis. Although survival and time to metamorphosis were not significantly affected, larval development tended to be shortened in the Bti treated water phase. Furthermore, exposure to Bti induced significant increases of GST (37-550%), GR (5-140%) and AChE (38-137%) irrespectively of the applied formulation, indicating detoxification, antioxidant responses as well as an alteration of neuronal activity. GST activity increased twice as much after two repeatedly executed Bti applications within a time period of 6 days. The examination of several biochemical markers is needed to fully evaluate the ecotoxicological risk of Bti for amphibian populations, especially in the context of worldwide amphibian declines. Nevertheless, following the precautionary principle, it may be advisable to implement certain thresholds for application numbers and intervals in order to ensure environmentally friendly mosquito control programs, especially in areas designated for nature conservation. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Bacterial Larvicide, Bacillus thuringiensis israelensis Strain AM 65-52 Water Dispersible Granule Formulation Impacts Both Dengue Vector, Aedes aegypti (L.) Population Density and Disease Transmission in Cambodia.

    Science.gov (United States)

    Setha, To; Chantha, Ngan; Benjamin, Seleena; Socheat, Doung

    2016-09-01

    A multi-phased study was conducted in Cambodia from 2005-2011 to measure the impact of larviciding with the bacterial larvicide, Bacillus thuringiensis israelensis (Bti), a water dispersible granule (WG) formulation on the vector, Aedes aegypti (L.) and the epidemiology. In our studies, all in-use containers were treated at 8 g/1000 L, including smaller containers and animal feeders which were found to contribute 23% of Ae aegypti pupae. The treated waters were subjected to routine water exchange activities. Pupal production was suppressed by an average 91% for 8 weeks. Pupal numbers continued to remain significantly lower than the untreated commune (UTC) for 13 weeks post treatment in the peak dengue vector season (ptreated commune. An average 70% of the household harbored 0-5 Ae aegypti mosquitoes per home for 8 weeks post treatment, but in the same period of time >50% of the household in the UTC harbored ≥11 mosquitoes per home. The adult population continued to remain at significantly much lower numbers in the Bti treated commune than in the UTC for 10-12 weeks post treatment (ptreatment in the 6 months monsoon season with complete coverage of the target districts achieved an overall dengue case reduction of 48% in the 6 treated districts compared to the previous year, 2010. Five untreated districts in the same province had an overwhelming increase of 352% of dengue cases during the same period of time. The larvicide efficacy, treatment of all in-use containers at the start of the monsoon season, together with treatment coverage of entire districts interrupted disease transmission in the temephos resistant province.

  12. 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

  13. Efeito residual de apresentações comerciais dos larvicidas temefos e Bacillus thuringiensis israelensis sobre larvas de Aedes aegypti em recipientes com renovação de água Residual effect of commercial applications of larvicides temefos and Bacillus thuringiensis israelensis on Aedes aegypti larvae in recipients with water renewal

    Directory of Open Access Journals (Sweden)

    Ricardo José Soares Pontes

    2005-08-01

    Full Text Available Avaliou-se o efeito residual do temefos (apresentações comerciais A, B, C e Bacillus thuringiensis israelensis (D e E sobre larvas de Aedes aegypti, em recipientes com renovação de água. Utilizaram-se 44 béqueres de 1.000ml (8 para cada apresentação e 4 controles. Em cada béquer introduziram-se diariamente 25 larvas. Após 24 horas, contavam-se as larvas mortas, esvaziavam-se os béqueres até 200ml, repunha-se o volume original e acrescentavam-se novas larvas. A duração do efeito residual máximo (100% de mortalidade foi: A-19; B-39; C-40; D-8; E-19 dias. A razão de mortalidade permaneceu equivalente entre todos os larvicidas durante 25 dias; B e C mostraram RM 2,40 vezes maior do que E entre 46-95 dias; B, comparado com A, mostrou RM 1,90-7,51 vezes maior entre 26-95 dias. Conclui-se pela maior eficácia de duas apresentações do temefos, mesmo em uma situação epidemiológica de longa exposição ao produto e com renovação de água dos recipientes.The residual effect of temefos (commercial applications A, B and C and Bacillus thuringiensis israelensis (D and E on Aedes aegypti larvae was evaluated, in recipients with water renewal. Forty-four beakers of 1,000ml each (8 for each application and 4 controls were used. In each beaker, 25 larvae were introduced daily. After 24 hours, the dead larvae were counted, the beakers emptied to 200ml and refilled to original volume, with addition of new larvae. The duration of the maximum residual effect (100% of mortality was: A-19; B-39; C-40; D-8; E-19 days. The mortality ratio of all applications remained equivalent for 25 days; B, C and E maintained MR equivalent up to 45 days; B and C showed MR 2.40 times greater than E, between 46-95 days; B, compared with A, showed MR 1.90-7.51 times greater between 26-95 days. The conclusion was greater effectiveness of two presentations of temefos, even in an epidemiological situation with long exposure to the product and renewal of water in

  14. Toxicity of Bacillus thuringiensis var. israelensis in aqueous suspension on the South American common frog Leptodactylus latrans (Anura: Leptodactylidae) tadpoles

    International Nuclear Information System (INIS)

    Lajmanovich, Rafael C.; Junges, Celina M.; Cabagna-Zenklusen, Mariana C.; Attademo, Andrés M.; Peltzer, Paola M.; Maglianese, Mariana; Márquez, Vanina E.; Beccaria, Alejandro J.

    2015-01-01

    The effects of commercial formulations of Bacillus thuringiensisvar.israelensis (Bti) on non-target organisms are still a matter of debate; in amphibians, the risks of Bti are little known. To evaluate the toxicity of a commercial liquid (aqueous suspension, AS) formulation of Bti (Introban ® ) on Leptodactylus latrans tadpoles, including median lethal concentration (LC 50 ) and no-and lowest–observed-effect concentrations (NOEC and LOEC, respectively), as well as the possible effects of Bti on oxidative responses, erythrocytes genotoxicity, and histology of the intestines. In the laboratory, tadpoles were exposed to nominal concentrations of 0 (control), 2.5, 5, 10, 20 and 40 mg/L of formulated Bti-AS. Glutathione S-transferase (GST) and catalase (CAT) activities, as well as formation of erythrocyte nuclear abnormalities (ENAs), and histological effect were measured in tadpoles displaying survival rates >85%. L. latrans tadpoles were sensitive to exposure to Bti-AS, reaching 100% mortality after 48 h of exposure at the highest concentration. Bti-AS induced GST and CAT enzymes and genotoxicity (erythrocyte's nuclear abnormalities), and caused intestine's histopathology. Our results demonstrate that toxicity of Bti-AS is dose-dependent for L. latrans tadpoles and that sublethal exposure alters enzymes of oxidative stress, induces genotoxicity, and causes intestine damage. Further research is needed to evaluate the ecotoxicological risk of the massive use of Bti formulations on amphibian populations that commonly used suburban wastewater or urban waterbodies to reproduce and where this biopesticide is frequently applied. - Highlights: • An ecotoxicological evaluation of a Bti formulation on amphibian was conducted. • Toxicity of Bti-AS was dose-dependent for Leptodactylus latrans tadpoles. • Sublethal exposure altered the enzymes of oxidative stress (GST and CAT). • Bti-AS was genotoxic because increased MN frequencies (CO: 0.82–2.74‰).

  15. Toxicity of Bacillus thuringiensis var. israelensis in aqueous suspension on the South American common frog Leptodactylus latrans (Anura: Leptodactylidae) tadpoles

    Energy Technology Data Exchange (ETDEWEB)

    Lajmanovich, Rafael C., E-mail: lajmanovich@hotmail.com [National Council for Scientific and Technical Research (CONICET), Buenos Aires (Argentina); Faculty of Biochemistry and Biological Sciences (FBCB-UNL), Ciudad Universitaria Paraje el Pozo s/n, 3000 Santa Fe (Argentina); Junges, Celina M. [National Council for Scientific and Technical Research (CONICET), Buenos Aires (Argentina); Faculty of Biochemistry and Biological Sciences (FBCB-UNL), Ciudad Universitaria Paraje el Pozo s/n, 3000 Santa Fe (Argentina); Cabagna-Zenklusen, Mariana C. [Faculty of Biochemistry and Biological Sciences (FBCB-UNL), Ciudad Universitaria Paraje el Pozo s/n, 3000 Santa Fe (Argentina); Attademo, Andrés M.; Peltzer, Paola M. [National Council for Scientific and Technical Research (CONICET), Buenos Aires (Argentina); Faculty of Biochemistry and Biological Sciences (FBCB-UNL), Ciudad Universitaria Paraje el Pozo s/n, 3000 Santa Fe (Argentina); Maglianese, Mariana; Márquez, Vanina E.; Beccaria, Alejandro J. [Faculty of Biochemistry and Biological Sciences (FBCB-UNL), Ciudad Universitaria Paraje el Pozo s/n, 3000 Santa Fe (Argentina)

    2015-01-15

    The effects of commercial formulations of Bacillus thuringiensisvar.israelensis (Bti) on non-target organisms are still a matter of debate; in amphibians, the risks of Bti are little known. To evaluate the toxicity of a commercial liquid (aqueous suspension, AS) formulation of Bti (Introban{sup ®}) on Leptodactylus latrans tadpoles, including median lethal concentration (LC{sub 50}) and no-and lowest–observed-effect concentrations (NOEC and LOEC, respectively), as well as the possible effects of Bti on oxidative responses, erythrocytes genotoxicity, and histology of the intestines. In the laboratory, tadpoles were exposed to nominal concentrations of 0 (control), 2.5, 5, 10, 20 and 40 mg/L of formulated Bti-AS. Glutathione S-transferase (GST) and catalase (CAT) activities, as well as formation of erythrocyte nuclear abnormalities (ENAs), and histological effect were measured in tadpoles displaying survival rates >85%. L. latrans tadpoles were sensitive to exposure to Bti-AS, reaching 100% mortality after 48 h of exposure at the highest concentration. Bti-AS induced GST and CAT enzymes and genotoxicity (erythrocyte's nuclear abnormalities), and caused intestine's histopathology. Our results demonstrate that toxicity of Bti-AS is dose-dependent for L. latrans tadpoles and that sublethal exposure alters enzymes of oxidative stress, induces genotoxicity, and causes intestine damage. Further research is needed to evaluate the ecotoxicological risk of the massive use of Bti formulations on amphibian populations that commonly used suburban wastewater or urban waterbodies to reproduce and where this biopesticide is frequently applied. - Highlights: • An ecotoxicological evaluation of a Bti formulation on amphibian was conducted. • Toxicity of Bti-AS was dose-dependent for Leptodactylus latrans tadpoles. • Sublethal exposure altered the enzymes of oxidative stress (GST and CAT). • Bti-AS was genotoxic because increased MN frequencies (CO: 0.82–2.74

  16. Eficiência e Persistência de Três Produtos Comerciais à Base de Bacillus thuringiensis israelensis e Bacillus sphaericus no controle de Culicidae (Diptera em Lagoas de Tratamento de Efluentes

    Directory of Open Access Journals (Sweden)

    Jose Lopes

    2010-11-01

    Abstract. The hematofagic effect caused by females belonging to some species of Culicidae on humans and animals can be directly related to pathogen transmission, allergic reactions and uneasiness. The emergence of populations resistant to chemical insecticides has fostered the use of alternative methods, mainly biological control. The trials were conducted in three effluent treatment lagoons, on larvae of Culicidae to test the efficiency and persistence of commercial products whose active principles are based on Bacillus thuringiensis israelensis Berliner and Bacillus sphaericus Neide. The products tested were Vectolex (a granulated formulation of B. sphaericus, Sphaericus (a liquid formulation of B. sphaericus and Bt-horus (a liquid formulation of B. thuringiensis. The products were applied biweekly and evaluations were conducted 0, 24, 48, 72, and 120 hours after each application. The lagoons were colonized by Culex nigripalpus Theobald (1.5%, Culex saltanensis Dyar (2.25%, and Culex quinquefasciatus Say (96.25%. Bt-horus reduced larvae by 89.06%, 83.97% and 89.96% at 24, 48 and 72 hours after product application, respectively. The granulated and the liquid formulations containing B. sphaericus reduced larvae by 98.89 % and 98.34% 24 hours after application, and by 99.79% and 99.78% after 48 hours, respectively. The products and the different formulations were effective in controlling larvae of all three Culicidae species in lagoons with high levels of organic matter, but the persistence was recorded in two and three days for products containing respectively B. sphaericus and B. thuringiensis israelensis.

  17. Escalamiento para la producción de un biopesticida a partir de B. thuringiensis subsp. israelensis en biorreactores de 20 y 200 Litros

    Directory of Open Access Journals (Sweden)

    Sergio Ordúz

    2000-02-01

    Full Text Available

    Bacillus thuringiensis es una bacteria gram positiva esporulada que en fase estacionaria expresa algunas endotoxinas, contra un amplio espectro de larvas de insectos. Para desarrollar un biopesticida con base en B. thuringiensis que sea competitivo localmente es necesario generar la tecnología necesaria para su producción masiva, por esta razón el objetivo del trabajo fue escalar el proceso para la producción de B. thuringiensis basándose en el coeficiente volumétrico de transferencia de oxígeno corregido por presión (KLap partiendo de un biorreactor de 20 litros hasta llegar a un biorreactor de 200 litros.

    Para llevar a cabo este objetivo se realizó en primer lugar una evaluación del KLa a diferentes velocidades de agitación y flujos de aire por el método dinámico con el fin de obtener un modelo matemático que relacionara las variables anteriores. Se realizaron diferentes fermentaciones en un biorreactor de 20 litros con 11 litros de medio de cultivo utilizando B. thuringiensis subesp. israelensis. La velocidad de agitación y el flujo de aire se fijaron con base en un diseño factorial 22 con punto central realizando una repetición por cada punto del diseño, a continuación se realizaron dos fermentaciones adicionales por fuera del diseño para corroborar los resultados. Las fermentaciones de mayor escala se realizaron en un biorreactor de 200 litros con 110 litros de medio de cultivo, la velocidad de agitación y el flujo de aire se fijaron con base en los resultados obtenidos en las

  18. Controle de Aedes (Stegomyia aegypti (Linnaeus, 1762 e Culex (Culex quinquefasciatus Say, 1823 através de formulados contendo Bacillus thuringiensis israelensis em temperaturas controladas

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    João Zequi

    2011-11-01

    Abstract. Aedes (Stegomyia aegypti (Linnaeus and Culex (Culex quinquefasciatus Say are important pathogen vectors in urban environments. This study was designed to evaluate commercial formulations containing Bacillus thuringiensis israelensis de Barjac for the control of Ae. aegypti and Cx. quinquefasciatus and to assess their efficiency as compared to manufacturers´ claims. The tested products were the liquid formulation of Aquabac® XT 1200 ITU/mg, Teknar® 3000AAU/mg, and Vectobac® AS 1200 ITU/mg, and the solid products Vectobac® WDG 3000 ITU/mg, Vectobac® Tablet 2200 ITU/mg, and the trial formulation of Biouel 500 ITU/mg. All products were tested at 25±2°C temperature and the liquid formulations were also tested at 15±2°C, 35±2°C, and at room temperature (25.37 to 28.73ºC. The experiments were conducted with 25 larvae at the early 4th stage, in 150 mL of distilled water; the dead larvae were counted 24 hours after product application. Results were analyzed using Probit to calculate CL50. The 25±2°C temperature, Vectobac WDG, and Vectobac Tablet were the most efficient in controlling Ae. aegypti, with CL50 of 0.10 (0.08 – 0.11 mg/L and 0.10 (0.09 – 0.11 mg/L, respectively. The most efficient products for Cx. quinquefasciatus were Vectobac WDG, Vectobac AS, Biouel, and Vectobac T. When the potency claimed by manufacturers was compared to our laboratory results, Biouel had the best performance for both species. Vectobac AS was the most efficient for both species of Culicidae tested at 15±2°C, 35±2°C and at room temperature (25.37 to 28.37°C. Lower product concentrations were required at 35±2°C room temperature to control Cx. quinquefasciatus than for Ae. aegypti.

  19. Producción de Bacillus thuringiensis H-14 var. Israelensis utilizando espárrago (Asparagus officinalis) y su uso potencial para el control de la Malaria en la Libertad- Perú

    OpenAIRE

    Franklin Vargas V; Judith Roldán R; Gina Zavaleta E; Miriam Gil F; Cynthia Ampuero R; Ana Burga; Bertha Moreno; Carlos Vergara D; Palmira Ventosilla L

    2001-01-01

    Objetivo: Estandarizar un medio, de cultivo utilizando la infusión de espárrago (Asparagus officinalis) para la producción masiva de Bacillus thuringiensis (Bti) H-14 var. israelensis y determinar el efecto biolarvicida del Bti sobre Anopheles sp en criaderos naturales del distrito Laredo durante los meses de Enero a Diciembre del 2000. Materiales y métodos: Se ensayaron 3 medios a base de infusión de espárrago blanco: M1: 100 mL de la infusión, pH 9; M2: 50 mL de la infusión con 50 mL de buf...

  20. Avaliação da eficácia do Bacillus thuringiensis var. israelensis no controle de formas imaturas do Aedes (Stegomyia aegypti ( Linnaeus, 1762 em ambiente de laboratório.

    Directory of Open Access Journals (Sweden)

    Cleber Barreto Espindola

    2008-03-01

    Full Text Available ResumoAedes aegypti (L., 1762 é considerado um mosquito cosmopolita, com ocorrência nas regiões tropicais e subtropicais. No Brasil, está restrito às vilas e cidades, sempre com características domiciliares e peridomicíliares e, raramente é encontrado em ambientes onde a densidade populacional é baixa. Este mosquito é o único vetor do arbovírus da dengue e da febre amarela urbana em todo território nacional, e é considerado um dos vetores mais importantes na veiculação de patógenos a humanos. A grande resistência dos mosquitos a inseticidas químicos e a freqüente preocupação social com a poluição ambiental, resultou na procura de alternativas para o controle desses insetos, tais como a utilização de bactérias entomopatogênicas. Esse trabalho foi realizado objetivando mensurar a eficácia dessa bactéria no controle das formas imaturas de Ae. aegypti. Para a realização deste, foram criadas individualmente 350 larvas de geração F2 de Ae. aegypti em copos plásticos de 200 ml, contendo 100 ml de água não clorada. Na contaminação foi usado 5mg de Bacillus thuringiensis var. israelensis para cada estágio larval. A análise estatística foi realizada pelo teste de Mann-Whitney a 5%. A mortalidade das larvas contaminadas foi de 100%, 98%, 98%, 100% e 4% para o 2º, 3º, 4º estágio e pupa A média do número de dias de vida das larvas após contaminação no 1º, 2º, 3º, 4º estágio e pupa foi de 1,36; 2,46; 1,24; 1,22 e 3,46 dias respectivamente, exceto para a pupa, a duração dos estágios foi menor para os indivíduos contaminados, (P<0,05. O B. thuringiensis var. israelensis demonstrou ser um bioinseticida eficaz, causando mortalidade total de 99,5% das larvas contaminadas, embora para a fase de pupa não tenha sido eficaz. Desta forma ele representa uma boa opção para o controle de larvas de Ae. aegypti, entretanto para as pupas, outras alternativas devem ser estudadas.Evaluation of efficacy of Bacillus

  1. Laboratory and field evaluation of formulated Bacillus thuringiensis var. israelensis as a feed additive and using topical applications for control of Musca domestica (Diptera: Muscidae) larvae in caged-poultry manure.

    Science.gov (United States)

    Mwamburi, L A; Laing, M D; Miller, R

    2011-02-01

    Infestations of house flies, Musca domestica L., are a continual problem around poultry establishments. Acute toxicity of two commercial Bacillus thuringiensis variety israelensis (Bti) formulations (water-dispersible granules and bran formulation) was evaluated against larvae in the laboratory and against natural populations of M. domestica larvae in the field applied in feed to chickens and as topical applications in the poultry houses. Bioassay data showed that susceptibility of M. domestica larvae increased to a given concentration of Bti as the duration of exposure increased. In the laboratory studies, the LC(50) values of Bti for the larvae ranged between 65 and 77.4 μg/ml. In the field, a concentration of 10 g Bti/kg of feed resulted in 90% reduction of larvae at 4 wk after treatment. A higher concentration (2 g/liter) of Bti in spray applications was not significantly more effective than the lower concentration of 1 g/liter. Adding Bti to chicken feed is potentially an efficient measure for the management and control of house flies in caged-poultry facilities. © 2011 Entomological Society of America

  2. 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

    Directory of Open Access Journals (Sweden)

    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.

  3. Levantamento de espécies de Odonata associadas à tanques de piscicultura e efeito de Bacillus thuringiensis var. israelensis sobre ninfas de Pantala flavescens (Fabricius, 1798 - DOI: 10.4025/actascibiolsci.v26i1.1655 Odonata species survey associated with psiculture tanks and Bacillus thuringiensis var. israelensis effect on Pantala flavescens (Fabricius, 1798 nymphs (Odonata: Libellulidae - DOI: 10.4025/actascibiolsci.v26i1.1655

    Directory of Open Access Journals (Sweden)

    Douglas Moisés Quintilhiano

    2004-04-01

    Full Text Available Várias estações de piscicultura que trabalham com a produção de alevinos ou peixes ornamentais têm apresentado problemas relacionados à predação de larvas, pós-larvas e alevinos por ninfas de insetos da Ordem Odonata. Dessa forma, objetivou-se fazer um levantamento de espécies de odonatos presentes em tanques de criação de peixes em dois municípios da região centro-oeste de Minas Gerais, assim como avaliar o efeito de Bacillus thuringiensis var. israelensis de Barjac sobre ninfas de Pantala flavescens (Fabricius, 1798 (Odonata: Libellulidae. Durante um período de três meses, foram realizadas coletas quinzenais, sendo os insetos adultos capturados com o auxílio de redes entomológicas e as ninfas, através de peneiras de malha fina, acopladas a cabos de madeira. As ninfas capturadas foram levadas para o laboratório onde foram individualizadas em caixas de isopor com capacidade para 2L, vedadas em sua extremidade superior com filó. Logo após a emergência dos adultos, esses foram mortos, acondicionados em envelopes e enviados para serem identificados. Os experimentos laboratoriais foram conduzidos em sala climatizada à 25 ± 2°C, UR de 70 ± 10% e fotofase de 12 horas. Ninfas de segundo ínstar de P. flavescens foram individualmente acondicionadas em caixas de isopor contendo cada uma 500mL de água livre de cloro e, estando essas no terceiro, quinto e sétimo ínstares, foram tratadas com B. thuringiensis var. israelensis, através do produto microbiano Vectobac®, em formulação granulada. O produto foi aplicado diretamente na água do recipiente de criação, em concentração indicada para o controle de larvas de culicídeos, duas concentrações superiores e duas inferiores a essa, além da testemunha, na qual não se aplicou o produto. As avaliações foram realizadas a 24, 48 e 72 horas após a aplicação do produto, registrando-se o número de insetos mortos em cada tratamento. Em ambos os experimentos, as ninfas

  4. Producción de Bacillus thuringiensis H-14 var. Israelensis utilizando espárrago (Asparagus officinalis y su uso potencial para el control de la Malaria en la Libertad- Perú

    Directory of Open Access Journals (Sweden)

    Franklin Vargas V

    2001-07-01

    Full Text Available Objetivo: Estandarizar un medio, de cultivo utilizando la infusión de espárrago (Asparagus officinalis para la producción masiva de Bacillus thuringiensis (Bti H-14 var. israelensis y determinar el efecto biolarvicida del Bti sobre Anopheles sp en criaderos naturales del distrito Laredo durante los meses de Enero a Diciembre del 2000. Materiales y métodos: Se ensayaron 3 medios a base de infusión de espárrago blanco: M1: 100 mL de la infusión, pH 9; M2: 50 mL de la infusión con 50 mL de buffer fosfato, pH 7; y M3: 25 mL de la infusión con 75 mL de agua destilada, pH 9. Como control se utilizó el medio estándar TPH. La producción de Bti en los medios de cultivo fueron evaluadas para determinar la efectividad biolarvicida a través del LC50 y LC90. El medio de cultivo óptimo (menor LC50 y LC90 sirvió para la producción masiva del Bti, el cual se sometió a bioensayos de laboratorio y aplicaciones en criaderos naturales. La efectividad fue determinada mediante la densidad larvaria pre y post aplicación del Bti. Resultados: El medio de cultivo óptimo para la producción de Bti fue M1 mostrando alta efectividad, con 100% de mortalidad en condiciones de laboratorio y 71-97% de mortalidad en el campo a las 24 horas de exposición con 3 aplicaciones realizadas semanalmente. Conclusiones: M1 es el medio optimo para cultivar Bti, con alta efectividad para controlar larvas de Anopheles en el laboratorio y en el campo.

  5. Evaluation of methylated soy oil and water-based formulations of Bacillus thuringiensis var. Israelensis and Golden Bear Oil (GB-1111) against anopheles quadrimaculatus larvae in small rice plots.

    Science.gov (United States)

    Dennett, J A; Lampman, R L; Novak, R J; Meisch, M V

    2000-12-01

    The efficacy of formulations containing methylated soybean oil (MSO) alone and with technical-grade Bacillus thuringiensis var. israelensis (Bti) were compared to Golden Bear Oil (GB-1111) and a water-based Bti formulation against 3rd- to 4th-stage Anopheles quadrimaculatus larvae confined to sentinel cages in small rice plots. Three replicates each of MSO with 2% Pyroter added as a surfactant (MSO + PYR), MSO with 2% Pyroter and 4 g of Bti technical powder (MSO + PYR + Bti), GB-1111, a water-based formulation with 4 g of Bti technical powder (Bti + water), and untreated controls were performed. Mosquito larvae were introduced on the 1st day of treatment and at 4 days posttreatment. Mortality was recorded at 24 and 48 h posttreatment for the 1st installation and at 5 days posttreatment for the 2nd installation. The Bti + water formulation provided 71% control and the MSO + PYR + Bti formulation achieved 64% control, whereas MSO + PYR and GB-1111 produced 16 and 18% control, respectively, at 24 h posttreatment. With the exception of MSO + PYR + Bti, which decreased by 2%, the mean percent control increased slightly at 48h posttreatment across remaining treatments, with Bti + water obtaining 72% control. This was significantly higher than GB-1111, which achieved 23% control at 48 h posttreatment. The MSO + PYR and MSO + PYR + Bti formulations yielded 56 and 62% control, respectively, during the same interval and were not significantly different from one another. Formulations containing MSO + PYR exhibited delayed activity similar to GB-1111, with all formulations except MSO + PYR + Bti providing greatest control at 48 h posttreatment. Both MSO formulations (MSO + PYR + Bti and MSO + PYR) were statistically comparable to Bti + water and GB-1111, respectively, at 24 and 48 h posttreatment. None of the formulations exhibited a residual activity adequate enough to control An. quadrimaculatus larvae for up to 5 days.

  6. 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...

  7. 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.

  8. Enhanced toxicity of Bacillus thuringiensis subspecies kurstaki and aizawai to black cutworm larvae (Lepidoptera: Noctuidae) with Bacillus sp. NFD2 and Pseudomonas sp. FNFD1.

    Science.gov (United States)

    Mashtoly, Tamer A; Abolmaaty, Assem; El-Zemaity, Mohamed El-said; Hussien, Mohamed I; Alm, Steven R

    2011-02-01

    Bacillus thuringiensis subspecies kurstaki and aizawai are important control agents for lepidopteran pests. Bioassays were designed to test B. t. kurstaki and aizawai against second- and-fourth instar black cutworm larvae with and without Bacillus sp. NFD2 and Pseudomonas sp. FNFD1 bacteria. B. thuringiensis subsp. aizawai (XenTari) was more toxic to both second- and fourth-instar black cutworm, Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae), larvae than B. t. kurstaki (DiPel) at 7 d after treatment (DAT). When DiPel was combined with NFD2 or FNFD1 versus second instars, the LC50s were 5.0X and 4.7X lower, respectively, than with DiPel alone. DiPel combined with both NFD2 and FNFD1 versus second instars resulted in an LC50 value 7.7X lower than with DiPel alone. When XenTari was combined with NFD2 or FNFD1 versus second instars, the LC50s were 5.2X and 3.8X lower, respectively, than with XenTari alone. XenTari combined with both NFD2 and FNFD1 versus second instars resulted in an LC50 9.7X lower than with XenTari alone. When DiPel was combined with NFD2 or FNFD1 versus fourth instars, the LC50s were 4.4X and 3.4X lower, respectively, than with DiPel alone. DiPel combined with both NFD2 and FNFD1 versus fourth instars resulted in an LC50 5.0X lower than with DiPel alone. When XenTari was combined with NFD2 or FNFD1 versus fourth instars, the LC50s were 5.7X and 3.3X lower, respectively, than with XenTari alone. XenTari combined with both NFD2 and FNFD1 versus fourth instars resulted in an LC50 6.7X lower than with XenTari alone.

  9. 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 ...

  10. 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 ...

  11. Sub-chronic lung inflammation after airway exposures to Bacillus thuringiensis biopesticides in mice

    DEFF Research Database (Denmark)

    Barfod, Kenneth K; Poulsen, Steen Seier; Hammer, Maria

    2010-01-01

    The aim of the present study was to assess possible health effects of airway exposures to Bacillus thuringiensis (Bt) based biopesticides in mice. Endpoints were lung inflammation evaluated by presence of inflammatory cells in bronchoalveolar lavage fluid (BALF), clearance of bacteria from the lung...... lumen and histological alterations of the lungs. Hazard identifications of the biopesticides were carried out using intratracheal (i.t.) instillation, followed by an inhalation study. The two commercial biopesticides used were based on the Bt. subspecies kurstaki and israelensis, respectively. Groups...... of BALB/c mice were i.t instilled with one bolus (3.5 × 105 or 3.4 × 106 colony forming units (CFU) per mouse) of either biopesticide. Control mice were instilled with sterile water. BALFs were collected and the inflammatory cells were counted and differentiated. The BALFs were also subjected to CFU...

  12. 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.

  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. Transgenic organisms expressing genes from Bacillus thuringiensis to combat insect pests.

    Science.gov (United States)

    Zaritsky, Arieh; Ben-Dov, Eitan; Borovsky, Dov; Boussiba, Sammy; Einav, Monica; Gindin, Galina; Horowitz, A Rami; Kolot, Mikhail; Melnikov, Olga; Mendel, Zvi; Yagil, Ezra

    2010-01-01

    Various subspecies (ssp.) of Bacillus thuringiensis (Bt) are considered the best agents known so far to control insects, being highly specific and safe, easily mass produced and with long shelf life.1 The para-crystalline body that is produced during sporulation in the exosporium includes polypeptides named δ-endotoxins, each killing a specific set of insects. The different entomopathogenic toxins of various Bt ssp. can be manipulated genetically in an educated way to construct more efficient transgenic bacteria or plants that express combinations of toxin genes to control pests.2 Joint research projects in our respective laboratories during the last decade demonstrate what can be done by implementing certain ideas using molecular biology with Bt ssp. israelensis (Bti) as a model system. Here, we describe our progress achieved with Gram-negative bacterial species, including cyanobacteria, and some preliminary experiments to form transgenic plants, mainly to control mosquitoes (Diptera), but also a particular Lepidopteran and Coleopteran pest species. In addition, a system is described by which environment-damaging genes can be removed from the recombinants thus alleviating procedures for obtaining permits to release them in nature. © 2010 Landes Bioscience

  15. Bacillus thuringiensis isolates entomopathogenic for Culex quinquefasciatus (Diptera: Culicidae and Anticarsia gemmatalis (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    V. Gobatto

    Full Text Available Samples of the Bacillus thuringiensis (Bt were collected from soil and insects. Eight isolates were selected from rural soil, 15 from urban soil and 11 from insects. These were evaluated for entomopathogenicity against larvae of Anticarsia gemmatalis and Culex quinquefasciatus. The pathogenicity tests showed that a higher percentage of isolates were active against A. gemmatalis (60% compared to C. quinquefasciatus (31%. Probit analysis (LC50 indicated that against A. gemmatalis four of the isolates presented values similar to the reference strain against A. gemmatalis, while against C. quinquefasciatus one isolate showed an LC50 similar to the reference strain (IPS-82. SDS-PAGE characterisation of two isolates showed a 27 kDa protein fraction related to the Bt subspecies israelensis cytolytic toxin (cyt gene. One 130 kDa protein, possibly related to the Bt crystal inclusions (cry1 gene, was identified in the other two isolates, which were more toxic for lepidoptera; another isolate presented a protein of 100 kDa. Some new local Bt isolates had similar LC50 probit values to the reference strains.

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

    African Journals Online (AJOL)

    Esem

    National Malaria Control Centre, P.O. Box 32509, Lusaka. Department of Biological ... Bs for malaria vector control and its integration with indoor residual .... Study Areas. Ibex hill/. Kalikiliki. Venta/. Manzi. Chamba valley. Chelstone. Anopheles coustani. Anopheles squamosus. Anopheles rufipes. Culex spp. +. +. -. +. +. +.

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

    African Journals Online (AJOL)

    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). If you would like more information about how to print, save, and work with PDFs, Highwire Press provides a helpful Frequently Asked Questions about PDFs.

  18. 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...

  19. Sub-chronic lung inflammation after airway exposures to Bacillus thuringiensis biopesticides in mice

    Directory of Open Access Journals (Sweden)

    Barfod Kenneth K

    2010-09-01

    Full Text Available Abstract Background The aim of the present study was to assess possible health effects of airway exposures to Bacillus thuringiensis (Bt based biopesticides in mice. Endpoints were lung inflammation evaluated by presence of inflammatory cells in bronchoalveolar lavage fluid (BALF, clearance of bacteria from the lung lumen and histological alterations of the lungs. Hazard identifications of the biopesticides were carried out using intratracheal (i.t. instillation, followed by an inhalation study. The two commercial biopesticides used were based on the Bt. subspecies kurstaki and israelensis, respectively. Groups of BALB/c mice were i.t instilled with one bolus (3.5 × 105 or 3.4 × 106 colony forming units (CFU per mouse of either biopesticide. Control mice were instilled with sterile water. BALFs were collected and the inflammatory cells were counted and differentiated. The BALFs were also subjected to CFU counts. Results BALF cytology showed an acute inflammatory response dominated by neutrophils 24 hours after instillation of biopesticide. Four days after instillation, the neutrophil number was normalised and inflammation was dominated by lymphocytes and eosinophils, whereas 70 days after instillation, the inflammation was interstitially located with few inflammatory cells present in the lung lumen. Half of the instilled mice had remaining CFU recovered from BALF 70 days after exposure. To gain further knowledge with relevance for risk assessment, mice were exposed to aerosols of biopesticide one hour per day for 2 × 5 days. Each mouse received 1.9 × 104 CFU Bt israelensis or 2.3 × 103 CFU Bt kurstaki per exposure. Seventy days after end of the aerosol exposures, 3 out of 17 mice had interstitial lung inflammation. CFU could be recovered from 1 out of 10 mice 70 days after exposure to aerosolised Bt kurstaki. Plethysmography showed that inhalation of Bt aerosol did not induce airway irritation. Conclusions Repeated low dose aerosol

  20. [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.

  1. 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

  2. Effect of Promoters and Plasmid Copy Number on Cyt1A Synthesis and Crystal Assembly in Bacillus thuringiensis.

    Science.gov (United States)

    Park, Hyun-Woo; Hice, Robert H; Federici, Brian A

    2016-01-01

    Cyt1Aa is a major mosquitocidal protein synthesized during sporulation of Bacillus thuringiensis subsp. israelensis, composing more than 50% of its parasporal body. This high level of synthesis is due to several factors including three strong sporulation-dependent promoters, a strong transcription termination sequence, and an associated 20-kDa helper protein. Cyt1Aa's toxicity is low compared to the Cry proteins of this species, namely, Cry4Aa, Cry4Ba, and Cry11Aa, but it nevertheless plays an important role in the biology of B. thuringiensis subsp. israelensis in that it synergizes their mosquitocidal toxicity and suppresses the evolution of resistance. In the present study, the effects of using different cyt1Aa promoter combinations and plasmid copy number on synthesis of Cyt1Aa were evaluated. Using the 4Q7 (plasmid-cured) strain of B. thuringiensis subsp. israelensis as an experimental host, a plasmid copy number of two or three yielded no Cyt1Aa, whereas a copy number of four yielded only small crystals, even when expression was driven by one of the wild-type promoters. However, using all three wild-type promoters and a plasmid copy number of 20 yielded Cyt1A crystals tenfold larger than those produced by one promoter and a plasmid copy number of four. High levels of Cyt1Aa synthesis resulted in significantly fewer spores per unit medium and imperfectly formed crystals. Similar results were obtained when Cyt1Aa synthesis was evaluated using the same expression constructs in a mutant strain of B. thuringiensis subsp. israelensis that lacks the cyt1Aa gene.

  3. 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.

  4. Isolation and molecular characterization of Bacillus thuringiensis found in soils of the Cerrado region of Brazil, and their toxicity to Aedes aegypti larvae

    Directory of Open Access Journals (Sweden)

    Katiane dos Santos Lobo

    Full Text Available ABSTRACT This study investigated the potential of Bacillus thuringiensis isolates obtained in the Cerrado region of the Brazilian state of Maranhão for the biological control of Aedes aegypti larvae. The isolates were obtained from soil samples and the identification of the B. thuringiensis colonies was based on morphological characteristics. Bioassays were run to assess the pathogenicity and toxicity of the different strains of the B. thuringiensis against third-instar larvae of A. aegypti. Protein profiles were obtained by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Polymerase chain reaction assays were used to detect the toxin genes found in the bacterial isolates. Overall, 12 (4.0% of the 300 isolates obtained from 45 soil samples were found to present larvicidal activity, with the BtMA-104, BtMA-401 and BtMA-560 isolates causing 100% of mortality. The BtMA-401 isolate was the most virulent, with the lowest median lethal concentration (LC50 (0.004 × 107 spores/mL, followed by the Bacillus thuringiensis var. israelensis standard (0.32 × 107 spores/mL. The protein profiles of BtMA-25 and BtMA-401 isolates indicated the presence of molecular mass consistent with the presence of the proteins Cry4Aa, Cry11Aa and Cyt1, similar to the profile of Bacillus thuringiensis var. israelensis IPS-82. Surprisingly, however, none of the cry and cyt genes analyzed were amplified in the isolate BtMA-401. The results of the present study revealed the larvicidal potential of B. thuringiensis isolates found in the soils of the Cerrado region from Maranhão, although further research will be necessary to better elucidate and describe other genes associated with the production of insecticidal toxins in these isolates.

  5. Of the 25 isolates studied, 88% had genes capable of killing insect ...

    African Journals Online (AJOL)

    Roderick L. Rolle

    2013-07-24

    Jul 24, 2013 ... and B. thuringiensis subspecies israelensis (Bti). These serotypes are important because they produce δ-endo- toxins that have insecticidal capabilities. Btk is used for the control of lepidopteran larvae while Bti is used to con- trol dipteran larvae. Studies of crystal genes carried by Bacillus thuringiensis ...

  6. Evaluation of Aedes Aegypti Presence and Abundance in Septic Tanks and Their Impacts on Dengue Transmission

    Science.gov (United States)

    2009-03-10

    for controlling larval development include using predaceous fish and copepods which feed on the larvae, the Bti protein from Bacillus thuringiensis ...of water jars, the use of Mesocyclops thermocyclopoides and Bacillus thuringiensis subspecies israelensis, and permethrin-treated lethal ovitraps...a portable document format ( PDF ) and converted to a tagged image file format (TIFF) using Bluebeam PDF Revu Standard Edition (Pasadena, CA). PCI

  7. 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...

  8. 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...

  9. 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).

  10. Effects and mechanisms of Bacillus thuringiensis crystal toxins for mosquito larvae.

    Science.gov (United States)

    Zhang, Qi; Hua, Gang; Adang, Michael J

    2017-10-01

    Bacillus thuringiensis is a Gram-positive aerobic bacterium that produces insecticidal crystalline inclusions during sporulation phases of the mother cell. The virulence factor, known as parasporal crystals, is composed of Cry and Cyt toxins. Most Cry toxins display a common 3-domain topology. Cry toxins exert intoxication through toxin activation, receptor binding and pore formation in a suitable larval gut environment. The mosquitocidal toxins of Bt subsp. israelensis (Bti) were found to be highly active against mosquito larvae and are widely used for vector control. Bt subsp. jegathesan is another strain which possesses high potency against broad range of mosquito larvae. The present review summarizes characterized receptors for Cry toxins in mosquito larvae, and will also discuss the diversity and effects of 3-D mosquitocidal Cry toxin and the ongoing research for Cry toxin mechanisms generated from investigations of lepidopteran and dipteran larvae. © 2016 Institute of Zoology, Chinese Academy of Sciences.

  11. 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.

  12. 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.

  13. Producción de Bacillus thurigiensis H-14 var. israelensis utilizando espárrago (Asparagus officinalis) y sus uso potencial para el control de la malaria en La Libertad - Perú

    OpenAIRE

    Vargas V, Franklin; Universidad Nacional de Trujillo; Roldán R, Judith; Universidad Nacional de Trujillo; Zavaleta E, Gina; Universidad Nacional de Trujillo; M, Gil; Ampuero R, Cynthia; Universidad Nacional de Trujillo; Burga, Ana; Dirección Regional de Salud La Libertad; Moreno, Bertha; Dirección Regional de Salud La Libertad; Vergara D, Carlos; Sanidad Policial III, Región La Libertad; Ventosilla L, Palmira; Universidad Peruana Cayetano Heredia

    2001-01-01

    Objetivo: Estandarizar un medio de cultivo utilizando la infusión de espárrago (Asparagus officinalis) para la producción masiva de Bacillus thuringiensis (Bti) H-14 var. israelensis y determinar el efecto biolarvicida del Bti sobre Anopheles sp en criaderos naturales del distrito Laredo durante los meses de Enero a Diciembre del 2000. Materiales y métodos: Se ensayaron 3 medios a base de infusión de espárrago blanco: M1: 100 mL de la infusión, pH 9; M2: 50 mL de la infusión con 50 mL de buff...

  14. 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.

  15. SUBSPECIALIZATION IN THE FIELD OF ORTHOPAEDIC SURGERY

    African Journals Online (AJOL)

    rationale for the application of orthopaedic subspecialization in the developing world. Data source: A pubmed search with the mesh term “subspecialization.” Data selection/extraction: Using the pubmed search engine, 452 abstracts were found discussing subspecialization. Twenty two relevant articles were found, studied ...

  16. Identification of new isolates of Bacillus thuringiensis using rep-PCR products and delta-endotoxin electron microscopy

    Directory of Open Access Journals (Sweden)

    A.S.G. Lima

    2002-01-01

    Full Text Available PCR has been used to analyze the distribution of REP (Repetitive Extragenic Palindromic and ERIC (Enterobacterial Repetitive Intergenic Consensus sequences (rep-PCR found within the genome of the bacterium Bacillus thuringiensis, with the purpose to analyze the genetic similarities among 56 subspecies samples and 95 field isolates. The PCR products were analyzed by EB-AGE (ethidium bromide-agarose electrophoresis and then submitted to banding comparisons, based on the Phyllip software algorithm. When the banding similarities were considered for comparison purposes among all the strains, the phylogenic tree patterns varied according to the rep-PCR primers considered, but, from a broader point of view, the ERIC sequences produced better results, which, together with electron microscopy analysis of the released parasporal bodies and colony morphology characteristics, allowed to detect two possible new subspecies of B. thuringiensis.

  17. Identification of new isolates of Bacillus thuringiensis using rep-PCR products and d-endotoxin electron microscopy

    Directory of Open Access Journals (Sweden)

    Lima A.S.G.

    2002-01-01

    Full Text Available PCR has been used to analyze the distribution of REP (Repetitive Extragenic Palindromic and ERIC (Enterobacterial Repetitive Intergenic Consensus sequences (rep-PCR found within the genome of the bacterium Bacillus thuringiensis, with the purpose to analyze the genetic similarities among 56 subspecies samples and 95 field isolates. The PCR products were analyzed by EB-AGE (ethidium bromide-agarose electrophoresis and then submitted to banding comparisons, based on the Phyllip software algorithm. When the banding similarities were considered for comparison purposes among all the strains, the phylogenic tree patterns varied according to the rep-PCR primers considered, but, from a broader point of view, the ERIC sequences produced better results, which, together with electron microscopy analysis of the released parasporal bodies and colony morphology characteristics, allowed to detect two possible new subspecies of B. thuringiensis.

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

    Directory of Open Access Journals (Sweden)

    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.

  19. 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.

  20. 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.

  1. 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...

  2. The susceptibility of five African Anopheles species to Anabaena PCC 7120 expressing Bacillus thuringiensis subsp. israelensis mosquitocidal cry genes.

    Science.gov (United States)

    Ketseoglou, Irene; Bouwer, Gustav

    2012-10-04

    Malaria, one of the leading causes of death in Africa, is transmitted by the bite of an infected female Anopheles mosquito. Problems associated with the development of resistance to chemical insecticides and concerns about the non-target effects and persistence of chemical insecticides have prompted the development of environmentally friendly mosquito control agents. The aim of this study was to evaluate the larvicidal activity of a genetically engineered cyanobacterium, Anabaena PCC 7120#11, against five African Anopheles species in laboratory bioassays. There were significant differences in the susceptibility of the anopheline species to PCC 7120#11. The ranking of the larvicidal activity of PCC 7120#11 against species in the An. gambiae complex was: An. merus PCC 7120#11 against the important malaria vectors An. gambiae and An. arabiensis was 12.3 × 10⁵ cells/ml and 8.10 × 105 cells/ml, respectively. PCC 7120#11 was not effective against An. funestus, with less than 50% mortality obtained at concentrations as high as 3.20 × 10⁷ cells/ml. PCC 7120#11 exhibited good larvicidal activity against larvae of the An. gambiae complex, but relatively weak larvicidal activity against An. funestus. The study has highlighted the importance of evaluating a novel mosquitocidal agent against a range of malaria vectors so as to obtain a clear understanding of the agent's spectrum of activity and potential as a vector control agent.

  3. Integrated Use of Planaria (Dugesia dorotocephala) and Bacillus thuringiensis var. Israelensis against Aedes Taeniorhynchus: A Laboratory Bioassay

    Science.gov (United States)

    1990-12-01

    predatory planarian , Dugesia dorotoce- against Ae. taeniorhynchus under phala (Woodworth), and the microbial larvicide, andplanaria ins. u Bacillus...association between B.t.i. and planaria, The opinions or assertions contained herein are and planarian consumption of B.t.i.-dosed mos- the private views of...specifically, 3 Kenk, R. 1972. Freshwater planarians [Turbellarial of species of minnows, due to 2 factors: (1) imme- North America. Biota of

  4. Investigation of Bacillus thuringiensis var. israelensis (Bti endotoxin production and analysis of efficiency of Bti against mosquito larvae

    Directory of Open Access Journals (Sweden)

    RASHMI GWAL

    2015-04-01

    Full Text Available Mosquitoes are dangerous to mankind and are threatening human life worldwide. Insect specific toxins, which are commonly produced by Bti, are becoming an important component of biological strategies to control mosquito's population that causes communicable or life threatening diseases. These insect specific toxins are commonly known as biolarvicides. Biolarvicides of strain Bti are highly effective against mosquito's larvae at very low doses and show no harmful effects to other non-target organisms. Therefore, Bti has been extensively used in mosquito control programs. No field resistance has been observed in mosquitoes populations treated with Bti. This suggests that Bti will be an effective biocontrol agent for years. In the present study, we evaluated the efficacy of Bti against mosquito larvae (Culex quinquefasciatus commonly found in central India, Bhopal, Madhya Pradesh. The formulation was effective in killing mosquito larvae and its international toxic unit was found to be 5200 ITU/mg.

  5. The susceptibility of five African Anopheles species to Anabaena PCC 7120 expressing Bacillus thuringiensis subsp. israelensis mosquitocidal cry genes

    Directory of Open Access Journals (Sweden)

    Ketseoglou Irene

    2012-10-01

    Full Text Available Abstract Background Malaria, one of the leading causes of death in Africa, is transmitted by the bite of an infected female Anopheles mosquito. Problems associated with the development of resistance to chemical insecticides and concerns about the non-target effects and persistence of chemical insecticides have prompted the development of environmentally friendly mosquito control agents. The aim of this study was to evaluate the larvicidal activity of a genetically engineered cyanobacterium, Anabaena PCC 7120#11, against five African Anopheles species in laboratory bioassays. Findings There were significant differences in the susceptibility of the anopheline species to PCC 7120#11. The ranking of the larvicidal activity of PCC 7120#11 against species in the An. gambiae complex was: An. merus An. arabiensis An. gambiae An. quadriannulatus, where 50. The LC50 of PCC 7120#11 against the important malaria vectors An. gambiae and An. arabiensis was 12.3 × 105 cells/ml and 8.10 × 105 cells/ml, respectively. PCC 7120#11 was not effective against An. funestus, with less than 50% mortality obtained at concentrations as high as 3.20 × 107 cells/ml. Conclusions PCC 7120#11 exhibited good larvicidal activity against larvae of the An. gambiae complex, but relatively weak larvicidal activity against An. funestus. The study has highlighted the importance of evaluating a novel mosquitocidal agent against a range of malaria vectors so as to obtain a clear understanding of the agent’s spectrum of activity and potential as a vector control agent.

  6. 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...

  7. Toxin stability improvement and toxicity increase against dipteran and lepidopteran larvae of Bacillus thuringiensis crystal protein Cry2Aa.

    Science.gov (United States)

    Elleuch, Jihen; Jaoua, Samir; Ginibre, Carole; Chandre, Fabrice; Tounsi, Slim; Zghal, Raida Z

    2016-12-01

    Bacillus thuringiensis δ-endotoxins are the most widely used biopesticides for controlling economically important crop pests and disease vectors. Improving their efficacy is of great benefit. Here, an improvement in Cry2Aa δ-endotoxin toxicity was attempted via a cry gene over expression system using P20 from B. thuringiensis israelensis. The coexpression of Cry2Aa with P20 resulted in a seven fold increase in its production yield in B. thuringiensis. Generated crystals proved to be significantly more toxic (505.207 µg g -1 , 1.99 mg L -1 and 1.49 mg L -1 ) than the P20-lacking control (720.78 µg g -1 , 705.69 mg L -1 and 508.51 mg L -1 ) against Ephestia kuehniella, Aedes aegypti and Culex pipiens larvae respectively. In vitro, processing experiments revealed a P20-mediated protection of Cry2Aa against degradation under larval gut conditions. Thus, P20 could promote the maintenance of a tightly packaged conformation of Cry2Aa toxins in the larval midgut upon correct activation and binding to its membrane receptors. Based on their resistance against excessive proteolysis, Cry2Aa δ-endotoxins, produced in the presence of P20, could be considered as a successful control agent for E. kuehniella and an effective alternative for mosquito control, implying its possible exploitation in pest management programmes. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  8. Insecticidal potency of bacterial species Bacillus thuringiensis SV2 and Serratia nematodiphila SV6 against larvae of mosquito species Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus.

    Science.gov (United States)

    Patil, Chandrashekhar D; Patil, Satish V; Salunke, Bipinchandra K; Salunkhe, Rahul B

    2012-05-01

    The tremendous worldwide efforts to isolate novel mosquito larvicidal bacteria with improved efficacy present significant promise to control vector-borne diseases of public health importance. In the present study, two native bacterial isolates, Bacillus thuringiensis (Bt SV2) and Serratia species (SV6) were evaluated for mosquito larvicidal potential against the early fourth instar larvae of Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus with reference to B. thuringiensis subsp. israelensis (Bti) H 14. The native Gram-positive, spore-forming Bt SV2 isolate showed 100% mortality against early fourth instars of Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus, in parallel to Bti H14 strain. After 24 h, Bt SV2 showed 98%, 89%, and 80.67%, and Bti H14 showed 92%, 98.33%, and 60% mortality against Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus, respectively. Serratia SV6 showed highest activity against Culex quinquefasciatus (100%) followed by Anopheles stephensi (95%) and Aedes aegypti (91%) after 48 h of exposure. The Gram-negative Serratia SV6 showed delayed toxicity compared to Bti H14 and Bt SV2 against early fourth instars of Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. The relative mortality of all treatments after 12-h exposures showed the varied toxicity with respect to exposure time, bacterial treatment, and mosquito species. Genetic relatedness of the strains was confirmed on the basis of phylogenetic reconstructions based on alignment of 16S rRNA gene sequences which indicated a strong clustering of the strain SV2 with B. thuringiensis and the strain SV6 with Serratia nematodiphila. In conclusion, the native isolate B. thuringiensis SV2 showed significant toxicity while Serratia SV6 showed less and delayed toxicity against several mosquito species compared with BtiH14. They may be used as novel bacterial insecticidal agents in mosquito vector-borne disease control. To our knowledge, this is the

  9. 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

  10. Genome characterization of Pasteurella multocida subspecies septica and comparison with Pasteurella multocida subspecies multocida and gallicida.

    Science.gov (United States)

    Peng, Zhong; Liang, Wan; Liu, Wenjing; Chen, Huanchun; Wu, Bin

    2017-05-01

    Pasteurella multocida: subspecies multocida, gallicida, and septica are noted to have a contribution to fowl cholera, a life-threatening disease to both domestic and wild bird species. The genome sequences of avian P. multocida subspecies gallicida and multocida have been well analyzed and compared. However, the genome characterization of avian P. multocida subspecies septica is rarely discussed. In this study, we determined the draft genome sequence of a virulent P. multocida subspecies septica serogroup A strain HB02. The genome of P. multocida HB02 was composed of a single chromosome of 2,213,604 bp with a 40.27% G + C content, which showed a similar genome size and %GC content to the P. multocida subspecies multocida and gallicida genomes. The entire sequence specified 2002 putative coding DNA sequences plus 2 encoded rRNAs and 46 encoded tRNAs. In addition, the subspecies septica had a similar content of genes coding for metabolic traits that found in the subspecies gallicida and multocida. In addition, comparison of virulent versus avirulent avian P. multocida genomes identified 657 unique genes in either of the virulent strains HB02, P1059 and/or X73 compared to the avirulent strain Pm70. These genes should be the potential virulence-associated genes. Our work may add a novel genome sequence for the avian P. multocida genome database and shed a light on the pathogenesis of P. multocida.

  11. Proposal to create subspecies of Rickettsia conorii based on multi-locus sequence typing and an emended description of Rickettsia conorii

    Directory of Open Access Journals (Sweden)

    Raoult Didier

    2005-03-01

    , R. conorii subspecies indica subsp. nov. (type strain = ATCC VR-597, R. conorii subspecies caspia subsp. nov. (type strain = A-167, and R. conorii subspecies israelensis subsp. nov. (type strain = ISTT CDC1. The description of R. conorii is emended to accomodate the four subspecies.

  12. 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 ...

  13. Salinity-tolerant larvae of mosquito vectors in the tropical coast of Jaffna, Sri Lanka and the effect of salinity on the toxicity of Bacillus thuringiensis to Aedes aegypti larvae.

    Science.gov (United States)

    Jude, Pavilupillai J; Tharmasegaram, Tharmatha; Sivasubramaniyam, Gobika; Senthilnanthanan, Meena; Kannathasan, Selvam; Raveendran, Selvarajah; Ramasamy, Ranjan; Surendran, Sinnathamby N

    2012-11-22

    Dengue, chikungunya, malaria, filariasis and Japanese encephalitis are common mosquito-borne diseases endemic to Sri Lanka. Aedes aegypti and Aedes albopictus, the major vectors of dengue, were recently shown to undergo pre-imaginal development in brackish water bodies in the island. A limited survey of selected coastal localities of the Jaffna district in northern Sri Lanka was carried out to identify mosquito species undergoing pre-imaginal development in brackish and saline waters. The effect of salinity on the toxicity of Bacillus thuringiensis israelensis larvicide to Ae. aegypti larvae at salinity levels naturally tolerated by Ae. aegypti was examined. Larvae collected at the selected sites along the Jaffna coast were identified and salinity of habitat water determined in the laboratory. The LC₅₀ and LC₉₀ of B. thuringiensis toxin, the active ingredient of a commercial formulation of the larvicide BACTIVEC®, were determined with Ae. aegypti larvae. Bioassays were also carried out at salinities varying from 0 to 18 ppt to determine the toxicity of Bacillus thuringiensis to fresh and brackish water-derived larvae of Ae. aegypti. Larvae of four Anopheles, two Aedes, one Culex and one Lutzia species were collected from brackish and saline sites with salinity in the range 2 to 68 ppt. The LC₅₀ and LC₉₀ of B. thuringiensis toxin for the second instar larvae of Ae. aegypti in fresh water were 0.006 ppm and 0.013 ppm respectively, with corresponding values for brackish water populations of 0.008 and 0.012 ppm respectively. One hundred percent survival of second instar fresh water and brackish water-derived Ae. aegypti larvae was recorded at salinity up to 10 and 12 ppt and 100% mortality at 16 and 18 ppt, yielding an LC₉₀ for salinity of 13.9 ppt and 15.4 ppt at 24 h post-treatment respectively for the two populations. Statistical analysis showed significantly reduced toxicity of B. thuringiensis to fresh and brackish water-derived Ae. aegypti

  14. Molecular characterization of a DNA fragment harboring the replicon of pBMB165 from Bacillus thuringiensis subsp. tenebrionis

    Directory of Open Access Journals (Sweden)

    Yu Ziniu

    2006-10-01

    Full Text Available Abstract Background Bacillus thuringiensis belongs to the Bacillus cereus sensu lato group of Gram-positive and spore-forming bacteria. Most isolates of B. thuringiensis can bear many endogenous plasmids, and the number and size of these plasmids can vary widely among strains or subspecies. As far as we know, the replicon of the plasmid pBMB165 is the first instance of a plasmid replicon being isolated from subsp. tenebrionis and characterized. Results A 20 kb DNA fragment containing a plasmid replicon was isolated from B. thuringiensis subsp. tenebrionis YBT-1765 and characterized. By Southern blot analysis, this replicon region was determined to be located on pBMB165, the largest detected plasmid (about 82 kb of strain YBT-1765. Deletion analysis revealed that a replication initiation protein (Rep165, an origin of replication (ori165 and an iteron region were required for replication. In addition, two overlapping ORFs (orf6 and orf10 were found to be involved in stability control of plasmid. Sequence comparison showed that the replicon of pBMB165 was homologous to the pAMβ1 family replicons, indicating that the pBMB165 replicon belongs to this family. The presence of five transposable elements or remnants thereof in close proximity to and within the replicon control region led us to speculate that genetic exchange and recombination are potentially responsible for the divergence among the replicons of this plasmid family. Conclusion The replication and stability features of the pBMB165 from B. thuringiensis subsp. tenebrionis YBT-1765 were identified. Of particular interest is the homology and divergence shared between the pBMB165 replicon and other pAMβ1 family replicons.

  15. 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...

  16. 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.

  17. 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 ...

  18. 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, ...

  19. 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 ...

  20. 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 ...

  1. 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.

  2. A new subspecies of Typhlosaurus lineatus Boulenger 1887 ...

    African Journals Online (AJOL)

    1986-10-01

    Oct 1, 1986 ... totale ventrale skubteliings. Geografiese afsondering is oak duidelik. Introduction. The genus TyphlosauTlls Wiegmann. 1834 has recently been revised by Broadley (1968). He lists 12 species and subspecies including three subspecies of Tlinealus. One of these, T. I. subtaenialus Broadley. differs from the.

  3. 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)

  4. 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

    -term Bti application affects the structure of indigenous Bcg communities as well as the overall abundance of Bti. Based on new primers, group-specific quantitative PCR assays for Bcg and Bti in environmental samples were developed. On six occasions during the vegetation season, soil samples were collected......’t correlate with the number of Bti applications, indicating that Bti use influenced abundances of Bti on the short term while on the long term the number of treatments had only a limited effect. The findings illustrate the value of such investigations for understanding the ecology of Bti applications, which...

  5. ACTIVITY OF FREE AND CLAY-BOUND INSECTICIDAL PROTEINS FROM BACILLUS THURINGIENSIS SUBSP. ISRAELENSIS AGAINST THE MOSQUITO, CULEX PIPIENS. (R826107)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  6. Influence of environmental factors on the response of a natural population of Daphnia magna (Crustacea: Cladocera) to spinosad and Bacillus thuringiensis israelensis in Mediterranean coastal wetlands

    International Nuclear Information System (INIS)

    Duchet, C.; Caquet, Th.; Franquet, E.; Lagneau, C.; Lagadic, L.

    2010-01-01

    The present study was undertaken to assess the impact of a candidate mosquito larvicide, spinosad (8, 17 and 33 μg L -1 ) on a field population of Daphnia magna under natural variations of water temperature and salinity, using Bti (0.16 and 0.50 μL L -1 ) as the reference larvicide. Microcosms (125 L) were placed in a shallow temporary marsh where D. magna was naturally present. The peak of salinity observed during the 21-day observation period may have been partly responsible for the decrease of daphnid population density in all the microcosms. It is also probably responsible for the absence of recovery in the microcosms treated with spinosad which caused a sharp decrease of D. magna abundance within the first two days following treatment whereas Bti had no effect. These results suggest that it may be difficult for a field population of daphnids to cope simultaneously with natural (water salinity and temperature) and anthropogenic (larvicides) stressors. - Significant interaction between salinity and spinosad exposure impairs the recovery of a natural population of Daphnia magna.

  7. Influence of environmental factors on the response of a natural population of Daphnia magna (Crustacea: Cladocera) to spinosad and Bacillus thuringiensis israelensis in Mediterranean coastal wetlands

    Energy Technology Data Exchange (ETDEWEB)

    Duchet, C. [Entente Interdepartementale de Demoustication du Littoral Mediterraneen, 165 avenue Paul-Rimbaud, Montpellier F-34184 (France); INRA, UMR985 Ecologie et Sante des Ecosystemes, Equipe Ecotoxicologie et Qualite des Milieux Aquatiques, 65 rue de Saint Brieuc, Rennes F-35042 (France); Caquet, Th. [INRA, UMR985 Ecologie et Sante des Ecosystemes, Equipe Ecotoxicologie et Qualite des Milieux Aquatiques, 65 rue de Saint Brieuc, Rennes F-35042 (France); Franquet, E. [Universite Paul Cezanne, Institut Mediterraneen d' Ecologie et de Paleoecologie, Faculte des Sciences et Techniques Saint Jerome, C31, Marseille F-13397 (France); Lagneau, C. [Entente Interdepartementale de Demoustication du Littoral Mediterraneen, 165 avenue Paul-Rimbaud, Montpellier F-34184 (France); Lagadic, L., E-mail: Laurent.Lagadic@rennes.inra.f [INRA, UMR985 Ecologie et Sante des Ecosystemes, Equipe Ecotoxicologie et Qualite des Milieux Aquatiques, 65 rue de Saint Brieuc, Rennes F-35042 (France)

    2010-05-15

    The present study was undertaken to assess the impact of a candidate mosquito larvicide, spinosad (8, 17 and 33 mug L{sup -1}) on a field population of Daphnia magna under natural variations of water temperature and salinity, using Bti (0.16 and 0.50 muL L{sup -1}) as the reference larvicide. Microcosms (125 L) were placed in a shallow temporary marsh where D. magna was naturally present. The peak of salinity observed during the 21-day observation period may have been partly responsible for the decrease of daphnid population density in all the microcosms. It is also probably responsible for the absence of recovery in the microcosms treated with spinosad which caused a sharp decrease of D. magna abundance within the first two days following treatment whereas Bti had no effect. These results suggest that it may be difficult for a field population of daphnids to cope simultaneously with natural (water salinity and temperature) and anthropogenic (larvicides) stressors. - Significant interaction between salinity and spinosad exposure impairs the recovery of a natural population of Daphnia magna.

  8. LARVICIDAL TOXINS FROM BACILLUS THURINGIENSIS SUBSPP. KURSTAKI, MORRISONI (STRAIN TENEBRIONIS), AND ISRAELENSIS HAVE NO MICROBICIDAL OR MICROBIOSTATIC ACTIVITY AGAINST SELECTED BACTERIA, FUNGI, AND ALGAE IN VITRO. (R826107)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  9. [Control of culicides by using Bacillus thuringiensis SH-14 var. israelensis in permanent breeding places of Fomento, province of Sancti Spiritus, Cuba].

    Science.gov (United States)

    Cruz Pineda, Carlos Alberto; Montero Lago, Grisel; Navarro Ortega, Agustín; Morejón Martín, Pedro Lorenzo

    2005-01-01

    An ecological evaluation of retrospective and descriptive temporary trend was conducted from 1999 to 2000 .in 8 water bodies of Fomento, province of Sancti Spiritus. To evaluate the effectiveness and permanence of the biolarvicide, there were used data of systematic samplings and of control actions of the provincial surveillance and antivectorial fight programs taken from the records of each breeding place in the Municipal Unit of Higiene and Epidemiology of the locality. Doses of 10 ml of active ingredient per square meter were administered. It was attained the reduction and stabilization of the larval and adult indices in human primer of important species which are vectors of malaria, phyliriasis, and Western Nile's fever. The extension of the larval recovery range up to 3 weeks was proved.

  10. Alkaline phosphatases are involved in the response of Aedes aegypti larvae to intoxication with Bacillus thuringiensis subsp. israelensis Cry toxins.

    Science.gov (United States)

    Stalinski, Renaud; Laporte, Frédéric; Després, Laurence; Tetreau, Guillaume

    2016-03-01

    Bacillus thuringiensis subsp. israelensis (Bti) is a natural pathogen of dipterans widely used as a biological insecticide for mosquito control. To characterize the response of mosquitoes to intoxication with Bti, the transcriptome profile of Bti-exposed susceptible Aedes aegypti larvae was analysed using Illumina RNA-seq. Gene expression of 11 alkaline phosphatases (ALPs) was further investigated by real time quantitative polymerase chain reaction and ALP activity was measured in the susceptible strain and in four strains resistant to a single Bti Cry toxin or to Bti. These strains were unexposed or exposed to their toxin of selection. Although all resistant strains constitutively exhibited a higher level of transcription of ALP genes than the susceptible strain, they showed a lower total ALP activity. The intoxication with different individual Cry toxins triggered a global pattern of ALP gene under-transcription in all the one-toxin-resistant strains but involving different specific sets of ALPs in each resistant phenotype. Most of the ALPs involved are not known Cry-binding proteins. RNA interference experiment demonstrated that reducing ALP expression conferred increased the survival of larvae exposed to Cry4Aa, confirming the involvement of ALP in Cry4Aa toxicity. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  11. The Replacement of five Consecutive Amino Acids in the Cyt1A Protein of Bacillus thuringiensis Enhances its Cytotoxic Activity against Lung Epithelial Cancer Cells

    Directory of Open Access Journals (Sweden)

    Kavita Nair

    2018-03-01

    Full Text Available Cyt1A protein is a cytolytic protein encoded by the cyt gene of Bacillus thuringiensis subsp. israelensis (Bti as part of the parasporal crystal proteins produced during the sporulation. Cyt1A protein is unique compared to the other endotoxins present in these parasporal crystals. Unlike δ-endotoxins, Cyt1A protein does not require receptors to bind to the target cell and activate the toxicity. It has the ability to affect a broad range of cell types and organisms, due to this characteristic. Cyt1A has been recognized to not only target the insect cells directly, but also recruit other endotoxins by acting as receptors. Due to these mode of actions, Cyt1A has been studied for its cytolytic activity against human cancer cell lines, although not extensively. In this study, we report a novel Cyt1A protein produced by a Bti strain QBT229 isolated from Qatar. When tested for its cytotoxicity against lung cancer cells, this local strain showed considerably higher activity compared to that of the reference Bti and other strains tested. The possible reasons for such enhanced activity were explored at the gene and protein levels. It was evidenced that five consecutive amino acid replacements in the β8 sheet of the Cyt1A protein enhanced the cytotoxicity against the lung epithelial cancer cells. Such novel Cyt1A protein with high cytotoxicity against lung cancer cells has been characterized and reported through this study.

  12. 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.

  13. 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.

  14. 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.

  15. Multiplex PCR-based identification of Streptococcus canis, Streptococcus zooepidemicus and Streptococcus dysgalactiae subspecies from dogs.

    Science.gov (United States)

    Moriconi, M; Acke, E; Petrelli, D; Preziuso, S

    2017-02-01

    Streptococcus canis (S. canis), Streptococcus equi subspecies zooepidemicus (S. zooepidemicus) and Streptococcus dysgalactiae subspecies (S. dysgalactiae subspecies) are β-haemolytic Gram positive bacteria infecting animals and humans. S. canis and S. zooepidemicus are considered as two of the major zoonotic species of Streptococcus, while more research is needed on S. dysgalactiae subspecies bacteria. In this work, a multiplex-PCR protocol was tested on strains and clinical samples to detect S. canis, S. dysgalactiae subspecies and S. equi subspecies bacteria in dogs. All strains were correctly identified as S. canis, S. equi subspecies or S. dysgalactiae subspecies by the multiplex-PCR. The main Streptococcus species isolated from symptomatic dogs were confirmed S. canis. The multiplex-PCR protocol described is a rapid, accurate and efficient method for identifying S. canis, S. equi subspecies and S. dysgalactiae subspecies in dogs and could be used for diagnostic purposes and for epidemiological studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. 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.

  17. Proteomic Analysis of Bacillus thuringiensis at Different Growth Phases by Using an Automated Online Two-Dimensional Liquid Chromatography-Tandem Mass Spectrometry Strategy

    Science.gov (United States)

    Huang, Shaoya; Sun, Yunjun; Yang, Qi; Xiao, Xiuqing; Cao, Zhenping

    2012-01-01

    The proteome of a new Bacillus thuringiensis subsp. kurstaki strain, 4.0718, from the middle vegetative (T1), early sporulation (T2), and late sporulation (T3) phases was analyzed using an integrated liquid chromatography (LC)-based protein identification system. The system comprised two-dimensional (2D) LC coupled with nanoscale electrospray ionization (ESI) tandem mass spectrometry (MS/MS) on a high-resolution hybrid mass spectrometer with an automated data analysis system. After deletion of redundant proteins from the different batches and B. thuringiensis subspecies, 918, 703, and 778 proteins were identified in the respective three phases. Their molecular masses ranged from 4.6 Da to 477.4 Da, and their isoelectric points ranged from 4.01 to 11.84. Function clustering revealed that most of the proteins in the three phases were functional metabolic proteins, followed by proteins participating in cell processes. Small molecular and macromolecular metabolic proteins were further classified according to the Kyoto Encyclopedia of Genes and Genome and BioCyc metabolic pathway database. Three protoxins (Cry2Aa, Cry1Aa, and Cry1Ac) as well as a series of potential intracellular active factors were detected. Many significant proteins related to spore and crystal formation, including sporulation proteins, help proteins, chaperones, and so on, were identified. The expression patterns of two identified proteins, CotJc and glutamine synthetase, were validated by Western blot analysis, which further confirmed the MS results. This study is the first to use shotgun technology to research the proteome of B. thuringiensis. Valuable experimental data are provided regarding the methodology of analyzing the B. thuringiensis proteome (which can be used to produce insecticidal crystal proteins) and have been added to the related protein database. PMID:22636013

  18. 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

  19. Spectrophotometry of Artemisia tridentata to quantitatively determine subspecies

    Science.gov (United States)

    Richardson, Bryce; Boyd, Alicia; Tobiasson, Tanner; Germino, Matthew

    2018-01-01

    Ecological restoration is predicated on our abilities to discern plant taxa. Taxonomic identification is a first step in ensuring that plants are appropriately adapted to the site. An example of the need to identify taxonomic differences comes from big sagebrush (Artemisia tridentata). This species is composed of three predominant subspecies occupying distinct environmental niches, but overlap and hybridization are common in ecotones. Restoration of A. tridentata largely occurs using wildland collected seed, but there is uncertainty in the identification of subspecies or mix of subspecies from seed collections. Laboratory techniques that can determine subspecies composition would be desirable to ensure that subspecies match the restoration site environment. In this study, we use spectrophotometry to quantify chemical differences in the water-soluble compound, coumarin. Ultraviolet (UV) absorbance of A. tridentata subsp. vaseyana showed distinct differences among A.t. tridentata and wyomingensis. No UV absorbance differences were detected between A.t. tridentata and wyomingensis. Analyses of samples from > 600 plants growing in two common gardens showed that UV absorbance was unaffected by environment. Moreover, plant tissues (leaves and seed chaff) explained only a small amount of the variance. UV fluorescence of water-eluted plant tissue has been used for many years to indicate A.t. vaseyana; however, interpretation has been subjective. Use of spectrophotometry to acquire UV absorbance provides empirical results that can be used in seed testing laboratories using the seed chaff present with the seed to certify A. tridentata subspecies composition. On the basis of our methods, UV absorbance values 3.1 would indicate either A.t. tridentata or wyomingensis. UV absorbance values between 2.7 and 3.1 would indicate a mixture of A.t. vaseyana and the other two subspecies.

  20. A new record of Myxobolus brachysporus and M. israelensis in the tilapia (Oreochromis niloticus) collected from the Nile River, Egypt.

    Science.gov (United States)

    Abdel-Baki, Abdel-Azeem S; Zayed, Eman; Sakran, Thabet; Al-Quraishy, Saleh

    2015-09-01

    The present study was carried out as part of an ongoing general survey for myxosporean parasites infecting tilapias in the River Nile, Egypt. In the present study, 77 Nile tilapia (Oreochromis niloticus) were collected from boat landing sites at Beni-Suef governorate, Egypt and examined for the myxosporean infection. The infection was encountered as a huge number of free spores in the kidney and the spleen. The infection showed a prevalence of 51.9% (40/77) for Myxobolus brachysporus while it was 25.9% (20/77) for Myxobolus israelensis. Mature spores of M. brachysporus were ellipsoidal and measured 8.6 × 13.2 μm. The polar capsules were subcircular with 5-6 filament turns and measured 4.7 × 3.6 μm. Spores of M. israelensis were ellipsoidal in the frontal view and fusiform in the lateral view. Spore measurements were 13.4 μm long and 8.7 μm wide. The polar capsules were elongated with 6-7 filament coils and measured 8.6 × 3.1 μm. The findings presented here proved that tilapia fishes in the Nile River are still suffering from infections with Myxobolus species. Therefore, further studies should be carried out to survey the Myxobolus infection among tilapias under culture conditions to clarify the pathological impacts of this parasite in tilapias aquaculture.

  1. 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)

  2. 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.

  3. 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...

  4. 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.

  5. Use of UV absorption for identifying subspecies of Artemisia tridentata

    International Nuclear Information System (INIS)

    Spomer, G.G.; Henderson, D.M.

    1988-01-01

    Use of UV absorption spectra for identifying subspecies of Artemisia tridentata Nutt. was investigated by analyzing the relative optical densities of alcohol extracts from herbarium and fresh plant material at 240 nm, 250 nm, and 265 nm. In all but 1 comparison, mean relative optical densities were significantly different (p=0.95) between subspecies, but intraplant and intrasubspecies variation and overlap was found to be too large to permit use of UV absorbance alone for identifying individual specimens. These results held whether dry or fresh leaves were extracted, or whether methanol or ethanol was used as the extracting solvent. (author)

  6. 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...

  7. The complete mitochondrial DNA genome of a greater horseshoe bat subspecies, Rhinolophus ferrumequinum quelpartis (Chiroptera: Rhinolophidae).

    Science.gov (United States)

    Yoon, Kwang Bae; Kim, Ji Young; Kim, Hye Ri; Cho, Jae Youl; Park, Yung Chul

    2013-02-01

    There are two subspecies of Rhinolophus ferrumequinum currently recognized in South Korea. The Korean greater horseshoe bat subspecies, Rhinolophus ferrumequinum quelpartis, is distributed only in Jeju Island. The complete mitochondrial genome of the island subspecies was determined and revealed 99.7% similarity to the mainland subspecies Rhinolophus ferrumequinum korai. If d-loop region is excluded, similarity of the two genomes was 99.9%.

  8. The complete mitochondrial genome of a Chinese rufous horseshoe bat subspecies, Rhinolophus sinicus sinicus (Chiroptera: Rhinolophidae).

    Science.gov (United States)

    Sun, Haijian; Dong, Ji; Shi, Huizhen; Ren, Min; Hua, Panyu

    2016-09-01

    There are two subspecies of Rhinolophus sinicus currently recognized in China. In this study, using next generation sequencing approaches, the complete mitochondrial genome of one subspecies R. s. sinicus was obtained. The total length of the genome sequence is 16,898 bp. The arrangement and contents of R. s. sinicus mitochondrial genes exhibit high similarity with other bats of family Rhinolophida. Phylogenetic reconstructions support the sister relationship of the two subspecies and confirm the subspecies status of our specimen.

  9. Psychology Baccalaureates at Work: Major Area Subspecializations, Earnings, and Occupations

    Science.gov (United States)

    Rajecki, D. W.

    2012-01-01

    A Census Bureau national survey identified baccalaureates aged up to 64 years having major area subspecializations labeled "psychology," "industrial/organizational (I/O) psychology," and "counseling psychology." Median 2009 earnings of all such types of baccalaureate psychology alumni were well below the distribution mean of the 153 fields in the…

  10. Egyptian Vultures and the principle of subspecies in vultures

    African Journals Online (AJOL)

    Campbell Murn

    Donazar, J.A., Negro, J.J., Palacios, C.J., Gangoso, L., Godoy, J.A., Ceballos,. O., Hiraldo, F. & Capote, N. 2002. Description of a new subspecies of the. Egyptian Vulture (Accipitridae: Neophron percnopterus) from the Canary. Islands. Journal of Raptor Research 36: 17-23. Ferguson-Lees, J. & Christie, D.A. 2001. Raptors of ...

  11. Isolates of Mycoplasma mycoides subspecies mycoides (SC) in ...

    African Journals Online (AJOL)

    A study on the isolation of Mycoplasma mycoides subspecies mycoides (SC) in small ruminants and its implication on disease control was carried out in the Sahel zone of Nigeria. This was achieved by the examination of pneumonic lesions in apparently normal and affected lungs of sheep and goats slaughtered at ...

  12. Genetic diversity analysis and subspecies classification of Thailand ...

    African Journals Online (AJOL)

    Genetic diversity among 126 rice accessions, including 110 Thai landraces and 16 varieties used as subspecies reference, were evaluated by three types of DNA markers, InDel (Insertion/Deletion), inter-simple sequence repeat (ISSR) and simple sequence repeat (SSR) markers. Twelve InDel primer pairs, based on DNA ...

  13. Palynological characteristics of the heterostylous subspecies of Linum mucronatum Bertol

    Directory of Open Access Journals (Sweden)

    Talebi, S. M.

    2014-12-01

    Full Text Available Linum mucronatum is a heterostylous species from sect. Syllinum with four subspecies in Iran. The present study examines palynological characteristics of the heterostylous subspecies of Linum mucronatum, pollen characters of brevistylous individuals (pins as well as longistylous individuals (thrums of these plants by scanning electron microscope and light microscope using the prolonged acetolysis procedure. Sixteen qualitative and quantitative characters were investigated. Pollen equatorial shapes varied between pin and thrum individuals of each subspecies with the exception of L. mucronatum subsp. assyriacum. Pollen sculptures varied between pin and thrum samples of each subspecies and were seen in the gemmate, clavate and baculate shapes. In addition, quantitative palynological characters differed between plants and ANOVA test showed significant variations for traits such as equatorial length, colpi width and apocolpium diameter. Hetrostylous individuals of each subspecies were separated from others in the UPGMA tree and also in the PCO and PCA plots. This study confirmed variations in pollen features between pin and thrum individuals of each subspecies.Linum mucronatum es una especie con heterostilia, que pertenece a la sección Syllinum del género Linum, y tiene cuatro subespecies en Irán. En el presente estudio se examinan las características palinológicas de las subespecies heterostilas de Linum mucronatum Bertol., así como los caracteres polínicos de individuos de los morfos brevistilo (pin y longistilo (thrum de estas plantas, mediante microscopía electrónica de scanning y microscopía óptica usando el método de acetolisis prolongada. Se estudiaron un total de 16 caracteres cualitativos y cuantitativos. La forma ecuatorial del polen varía entre los morfos pin y thrum en todas las subspecies, excepto en L. mucronatum subsp. assyriacum. La ornamentación también varía entre las muestras de morfos pin y thrum de cada subespecie

  14. 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...

  15. Evaluation of two different culture media for the development of biopesticides based on Bacillus thuringiensis and their application in larvae of Aedes aegypti - doi: 10.4025/actascitechnol.v35i1.13831

    Directory of Open Access Journals (Sweden)

    Samara Ernandes

    2013-01-01

    Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 The bacteria Bacillus thuringiensis var. israelensis (Bti generates certain toxins with pesticide action, which can be used on the control of transmissible diseases by culicides, specially Aedes aegypti, the dengue vector. This biopesticide has been produced by submerged fermentation and, in Brazil, this production has been made by very little research centers and, more recently, by a unique small enterprise. For the implementation of a viable vectors control program through biopesticides, some studies about culture media are essential in order to join efficiency and low costs. In this way, agroindustrial wastes or by-products have been used as a nutrient source for the culture media production. In this study, corn steep liquor, a corn industrial processing by-product and tryptose, both with / without sugar addition, were compared as culture media. Cellular growth was evaluated by optical density at 620 nm, spore production by total viable cell count and LC50 by bioassays against 4th instar larvae. Among the four examined substrates, the medium composed by glucose plus corn steep liquor presented the best spore production and bioassay results.

  16. 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

  17. 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.

  18. A Large Scale Biorational Approach Using Bacillus thuringiensis israeliensis (Strain AM65-52 for Managing Aedes aegypti Populations to Prevent Dengue, Chikungunya and Zika Transmission.

    Directory of Open Access Journals (Sweden)

    Catherine A Pruszynski

    Full Text Available Aedes aegypti is a container-inhabiting mosquito and a vector of dengue, chikungunya, and Zika viruses. In 2009 several cases of autochthonous dengue transmission were reported in Key West, Florida, USA prompting a comprehensive response to control A. aegypti. In Key West, larvae of this mosquito develop in containers around human habitations which can be numerous and labor intensive to find and treat. Aerial applications of larvicide covering large areas in a short time can be an efficient and economical method to control A. aegypti. Bacillus thuringiensis israelensis (Bti is a bacterial larvicide which is highly target specific and appropriate for wide area spraying over urban areas, but to date, there are no studies that evaluate aerial spraying of Bti to control container mosquitoes like A. aegypti.This paper examines the effectiveness of aerial larvicide applications using VectoBac® WG, a commercially available Bti formulation, for A. aegypti control in an urban setting in the USA. Droplet characteristics and spray drop deposition were evaluated in Key West, Florida, USA. The mortality of A. aegypti in containers placed under canopy in an urban environment was also evaluated. Efficacy of multiple larvicide applications on adult female A. aegypti population reduction was compared between an untreated control and treatment site.Droplet characteristics showed that small droplets can penetrate through dense canopy to reach small containers. VectoBac WG droplets reached small containers under heavy canopy in sufficient amounts to cause > 55% mortality on all application days and >90% mortality on 3 of 5 application days while controls had 50%. Aerial larvicide applications using VectoBac WG can cover wide areas in a short period of time and can be effective in controlling A. aegypti and reducing A. aegypti-borne transmission in urban areas similar to Key West, Florida, USA.

  19. A Large Scale Biorational Approach Using Bacillus thuringiensis israeliensis (Strain AM65-52) for Managing Aedes aegypti Populations to Prevent Dengue, Chikungunya and Zika Transmission.

    Science.gov (United States)

    Pruszynski, Catherine A; Hribar, Lawrence J; Mickle, Robert; Leal, Andrea L

    2017-01-01

    Aedes aegypti is a container-inhabiting mosquito and a vector of dengue, chikungunya, and Zika viruses. In 2009 several cases of autochthonous dengue transmission were reported in Key West, Florida, USA prompting a comprehensive response to control A. aegypti. In Key West, larvae of this mosquito develop in containers around human habitations which can be numerous and labor intensive to find and treat. Aerial applications of larvicide covering large areas in a short time can be an efficient and economical method to control A. aegypti. Bacillus thuringiensis israelensis (Bti) is a bacterial larvicide which is highly target specific and appropriate for wide area spraying over urban areas, but to date, there are no studies that evaluate aerial spraying of Bti to control container mosquitoes like A. aegypti. This paper examines the effectiveness of aerial larvicide applications using VectoBac® WG, a commercially available Bti formulation, for A. aegypti control in an urban setting in the USA. Droplet characteristics and spray drop deposition were evaluated in Key West, Florida, USA. The mortality of A. aegypti in containers placed under canopy in an urban environment was also evaluated. Efficacy of multiple larvicide applications on adult female A. aegypti population reduction was compared between an untreated control and treatment site. Droplet characteristics showed that small droplets can penetrate through dense canopy to reach small containers. VectoBac WG droplets reached small containers under heavy canopy in sufficient amounts to cause > 55% mortality on all application days and >90% mortality on 3 of 5 application days while controls had treated sites was >50%. Aerial larvicide applications using VectoBac WG can cover wide areas in a short period of time and can be effective in controlling A. aegypti and reducing A. aegypti-borne transmission in urban areas similar to Key West, Florida, USA.

  20. 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.

  1. 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....

  2. 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

  3. 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...

  4. 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

  5. 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

  6. 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

  7. 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 ...

  8. 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.

  9. 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

  10. 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 ...

  11. 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.

  12. 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.

  13. 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 ...

  14. 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), ...

  15. 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 ...

  16. 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 ...

  17. 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).

  18. 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 ...

  19. 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 ...

  20. 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, ...

  1. 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 ...

  2. The molecular epidemiology of Treponema pallidum subspecies pallidum

    Science.gov (United States)

    Ma, Daphne Y.; Giacani, Lorenzo; Centurión-Lara, Arturo

    2017-01-01

    Pathogens adapt and evolve in response to pressures exerted by host environments, leading to generation of genetically diverse variants. Treponema pallidum subspecies pallidum displays a substantial amount of interstrain diversity. These variants have been identified in various parts of the world, indicating transmission linkage between geographical regions. Genotyping is based on molecular characterisation of various loci in the syphilis treponeme genome, but still require further development and continued research, as new bacterial types are continually being detected. The goal for studying the molecular epidemiology of Treponema pallidum variants is the global monitoring of the transmission of genetically distinct organisms with different drug sensitivities and, potentially, different virulence proprieties. PMID:25844928

  3. 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.

  4. Natural epigenetic variation within and among six subspecies of the house sparrow,Passer domesticus.

    Science.gov (United States)

    Riyahi, Sepand; Vilatersana, Roser; Schrey, Aaron W; Ghorbani Node, Hassan; Aliabadian, Mansour; Senar, Juan Carlos

    2017-11-01

    Epigenetic modifications can respond rapidly to environmental changes and can shape phenotypic variation in accordance with environmental stimuli. One of the most studied epigenetic marks is DNA methylation. In the present study, we used the methylation-sensitive amplified polymorphism (MSAP) technique to investigate the natural variation in DNA methylation within and among subspecies of the house sparrow, Passer domesticus We focused on five subspecies from the Middle East because they show great variation in many ecological traits and because this region is the probable origin for the house sparrow's commensal relationship with humans. We analysed house sparrows from Spain as an outgroup. The level of variation in DNA methylation was similar among the five house sparrow subspecies from the Middle East despite high phenotypic and environmental variation, but the non-commensal subspecies was differentiated from the other four (commensal) Middle Eastern subspecies. Further, the European subspecies was differentiated from all other subspecies in DNA methylation. Our results indicate that variation in DNA methylation does not strictly follow subspecies designations. We detected a correlation between methylation level and some morphological traits, such as standardized bill length, and we suggest that part of the high morphological variation in the native populations of the house sparrow is influenced by differentially methylated regions in specific loci throughout the genome. We also detected 10 differentially methylated loci among subspecies and three loci that differentiated between commensal or non-commensal status. Therefore, the MSAP technique detected larger scale differences among the European and non-commensal subspecies, but did not detect finer scale differences among the other Middle Eastern subspecies. © 2017. Published by The Company of Biologists Ltd.

  5. Validating bifidobacterial species and subspecies identity in commercial probiotic products.

    Science.gov (United States)

    Lewis, Zachery T; Shani, Guy; Masarweh, Chad F; Popovic, Mina; Frese, Steve A; Sela, David A; Underwood, Mark A; Mills, David A

    2016-03-01

    The ingestion of probiotics to attempt to improve health is increasingly common; however, quality control of some commercial products can be limited. Clinical practice is shifting toward the routine use of probiotics to aid in prevention of necrotizing enterocolitis in premature infants, and probiotic administration to term infants is increasingly common to treat colic and/or prevent atopic disease. Since bifidobacteria dominate the feces of healthy breast-fed infants, they are often included in infant-targeted probiotics. We evaluated 16 probiotic products to determine how well their label claims describe the species of detectable bifidobacteria in the product. Recently developed DNA-based methods were used as a primary means of identification, and were confirmed using culture-based techniques. We found that the contents of many bifidobacterial probiotic products differ from the ingredient list, sometimes at a subspecies level. Only 1 of the 16 probiotics perfectly matched its bifidobacterial label claims in all samples tested, and both pill-to-pill and lot-to-lot variation were observed. Given the known differences between various bifidobacterial species and subspecies in metabolic capacity and colonization abilities, the prevalence of misidentified bifidobacteria in these products is cause for concern for those involved in clinical trials and consumers of probiotic products.

  6. Relationship and genetic diversity of mistletoe (Viscum album L. subspecies

    Directory of Open Access Journals (Sweden)

    Leon Mejnartowicz

    2011-01-01

    Full Text Available With the help of 21 putative isoenzyme loci, the genetic diversity and variations of Viscum album ssp. album L. from 42 species, subspecies, varieties and hybrids of broadleaf trees, Viscum album ssp. austriacum (Wiesb. Vollmann, from 4 populations of Scots pine (Pinus sylvestris L. and Viscum album ssp. abietis (Wiesb. Abromeit, from 8 populations of European silver fir (Abies alba Mill. were analyzed. On the dendrogram, the three investigated subspecies form three clusters, each clearly separated from the other, so we suggest a revision of the systematic nomenclature proposed to take into consideration a return to an earlier system of dividing the European mistletoe into three species: Viscum album L., Viscum abietis Beck, and Viscum laxum Boiss. et Reut. From among the 21 tested loci only one locus, SOD-A, was monomorphic. The average number of actual alleles (Na and effective alleles (Ne was 2.23 and 1.61 respectively. The observed heterozygosity (Ho varied from 0.199 in V. album ssp. abietis to 0.345 in the V.a. ssp. album populations. Average FST = 0.277 indicates that about 28% of genetic differentiation is due to an interpopulation diversity of Viscum album populations. There is a small gene flux between Viscum album populations with only one immigrant successfully entering a population per two generations (Nm = 0,653.

  7. Rapid diagnosis of strangles (Streptococcus equi subspecies equi) using PCR.

    Science.gov (United States)

    Cordoni, Guido; Williams, Adele; Durham, Andy; Florio, Daniela; Zanoni, Renato Giulio; La Ragione, Roberto M

    2015-10-01

    Strangles is one of the most common equine infectious diseases with serious health, welfare and socio-economic impact. However, the detection of Streptococcus equi subspecies equi can be challenging and persistently infected carriers are common. Furthermore, the use of classical microbiology can result in an underestimation of the prevalence of the disease. The difficulties associated with the slow diagnosis of Strangles can result in rapid spread of the disease. Therefore, rapid and economical diagnostic tests are urgently required. Here, two multiplex assays, were developed and validated for the detection of S. equi and S. equi subspecies zooepidemicus, the most common differential diagnosis. Using 59 S. equi and 59 S. zooepidemicus strains collected from various geographical areas, the PCR tests demonstrated a sensitivity of 95% and a specificity of 98%. Furthermore, the assay can be performed directly from clinical swabs. Thus, the assays designed here provide a rapid, reliable and economical solution for the diagnosis of Strangles. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. 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

  9. 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...

  10. Three new species and one new subspecies of Toxorhynchites (Diptera: Culicidae) of the afrotropical region.

    Science.gov (United States)

    Ribeiro, Henrique

    2005-05-01

    Three new species and one new subspecies in the subgenus Afrorhynchus of the genus Toxorhynchites are described from the Afrotropical region. With the addition of these four new taxa, 14 species and two subspecies of subgenus Afrorhynchus are presently known in the region. Keys are provided for the identification of adult males and females of the subgenus Afrorhynchus in Africa.

  11. Subspecies recognition in Knot Calidris canutus and occurrence of races in Western Europe

    NARCIS (Netherlands)

    Roselaar, C.S.

    1983-01-01

    Based on migrant and winter specimens, 2 separate populations of Knot Calidris canutus are shown to occur in the Netherlands. Both are sufficiently differentiated to deserve recognition on subspecies level. Breeding range, migration routes, and winter areas of both these subspecies are defined.

  12. Precipitation of Carbonate Minerals Induced by the Halophilic Chromohalobacter Israelensis under High Salt Concentrations: Implications for Natural Environments

    Directory of Open Access Journals (Sweden)

    Zuozhen Han

    2017-06-01

    Full Text Available The precipitation of carbonate minerals induced by halophilic bacteria has aroused wide concern. The study aimed to investigate the characterization and process of biomineralization in high salt systems by halophilic Chromohalobacter israelensis LD532 (GenBank: KX766026 bacteria, isolated from the Yinjiashan Saltern in China. Carbonate minerals were induced in magnesium sulfate and magnesium chloride medium, respectively. The mineral phase, morphology, and elemental composition of minerals were analyzed using X-ray p owder diffraction, scanning electron microscopy, and energy dispersive X-ray detection. Cells and ultrathin slices were studied using high resolution transmission electron microscopy, selected area electron diffraction, and energy dispersive X-ray detection. The carbonic anhydrase and ammonia released from LD532 bacteria increased pH of the medium and promoted the carbonate precipitation. Magnesium calcite and aragonite were induced by LD532 bacteria in magnesium chloride medium at an Mg/Ca molar ratio of 2, while Magnesium calcite and monohydrocalcite were precipitated in magnesium sulfate medium at the same Mg/Ca ratio, only monohydrocalcite were formed in both control groups. The morphologies and compositions of minerals in MgSO4 and MgCl2 solutions displayed significant differences, indicating different Mg2+ could affect physiological and biochemical activities of LD532 bacteria and thus affect the mineral deposition. Further study showed the nucleation sites were located on extracellular polymeric substances and intracellular vesicles of LD532 bacteria. This study is beneficial to the mechanism of carbonate biomineralization in natural salt environments.

  13. Genetic subspecies diversity of the chimpanzee CD4 virus-receptor gene

    DEFF Research Database (Denmark)

    Hvilsom, Christina; Carlsen, Frands; Siegismund, Hans R

    2008-01-01

    Chimpanzees are naturally and asymptomatically infected by simian immunodeficiency virus (SIV). Pathogenic properties of SIV/HIV vary and differences in susceptibility and pathogenicity of SIV/HIV depend in part on host-specific factors such as virus-receptor/co-receptor interactions. Since CD4...... plays a primary role in virus binding and since SIVcpz have been found only in two African chimpanzee subspecies, we characterized the genetic diversity of CD4 receptors in all four recognized subspecies of chimpanzees. We found noticeable variation in the first variable region V1 of CD4 and in intron...... six among the subspecies of chimpanzees. We found the CD4 receptor to be conserved in individuals belonging to the P. t. verus subspecies and divergent from the other three subspecies, which harbored highly variable CD4 receptors. The CD4 receptor of chimpanzees differed from that of humans. We...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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.

  1. [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.

  2. Curcurbita pepo subspecies delineates striped cucumber beetle (Acalymma vittatum) preference

    Science.gov (United States)

    Brzozowski, L; Leckie, B M; Gardner, J; Hoffmann, M P; Mazourek, M

    2016-01-01

    The striped cucumber beetle (Acalymma vittatum (F.)) is a destructive pest of cucurbit crops, and management could be improved by host plant resistance, especially in organic farming systems. However, despite the variation in striped cucumber beetle preference observed within the economically important species, Cucurbita pepo L., plant breeders and entomologists lacked a simple framework to classify and exploit these differences. This study used recent phylogenetic evidence and bioassays to organize striped cucumber beetle preference within C. pepo. Our results indicate preference contrasts between the two agriculturally relevant subspecies: C. pepo subsp. texana and C. pepo subsp. pepo. Plants of C. pepo subsp. pepo were more strongly preferred than C. pepo subsp. texana plants. This structure of beetle preference in C. pepo will allow plant breeders and entomologists to better focus research efforts on host plant non-preference to control striped cucumber beetles. PMID:27347423

  3. Genome-wide sequence variations among Mycobacterium avium subspecies paratuberculosis.

    Directory of Open Access Journals (Sweden)

    Chung-Yi eHsu

    2011-12-01

    Full Text Available Mycobacterium avium subspecies paratuberculosis (M. ap, the causative agent of Johne’s disease (JD, infects many farmed ruminants, wildlife animals and humans. To better understand the molecular pathogenesis of these infections, we analyzed the whole genome sequences of several M. ap and M. avium subspecies avium (M. avium strains isolated from various hosts and environments. Using Next-generation sequencing technology, all 6 M. ap isolates showed a high percentage of homology (98% to the reference genome sequence of M. ap K-10 isolated from cattle. However, 2 M. avium isolates (DT 78 and Env 77 showed significant sequence diversity from the reference strain M. avium 104. The genomes of M. avium isolates DT 78 and Env 77 exhibited only 87% and 40% homology, respectively, to the M. avium 104 reference genome. Within the M. ap isolates, genomic rearrangements (insertions/deletions, Indels were not detected, and only unique single nucleotide polymorphisms (SNPs were observed among the 6 M. ap strains. While most of the SNPs (~100 in M. ap genomes were non-synonymous, a total of ~ 6000 SNPs were detected among M. avium genomes, most of them were synonymous suggesting a differential selective pressure between M. ap and M. avium isolates. In addition, SNPs-based phylo-genomic analysis showed that isolates from goat and Oryx are closely related to the cattle (K-10 strain while the human isolate (M. ap 4B is closely related to the environmental strains, indicating environmental source to human infections. Overall, SNPs were the most common variations among M. ap isolates while SNPs in addition to Indels were prevalent among M. avium isolates. Genomic variations will be useful in designing host-specific markers for the analysis of mycobacterial evolution and for developing novel diagnostics directed against Johne’s disease in animals.

  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. 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

  7. 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.

  8. 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.

  9. A Molecular Method for the Identification of Honey Bee Subspecies Used by Beekeepers in Russia

    Science.gov (United States)

    Syromyatnikov, Mikhail Y.; Borodachev, Anatoly V.; Kokina, Anastasia V.; Popov, Vasily N.

    2018-01-01

    Apis mellifera L. includes several recognized subspecies that differ in their biological properties and agricultural characteristics. Distinguishing between honey bee subspecies is complicated. We analyzed the Folmer region of the COX1 gene in honey bee subspecies cultivated at bee farms in Russia and identified subspecies-specific SNPs. DNA analysis revealed two clearly distinct haplogroups in A. mellifera mellifera. The first one was characterized by multiple cytosine-thymine (thymine–cytosine) transitions, one adenine-guanine substitution, and one thymine–adenine substitution. The nucleotide sequence of the second haplogroup coincided with sequences from other subspecies, except the unique C/A SNP at position 421 of the 658-bp Folmer region. A. mellifera carnica and A. mellifera carpatica could be distinguished from A. mellifera mellifera and A. mellifera caucasica by the presence of the A/G SNP at position 99 of the 658-bp Folmer region. The G/A SNP at position 448 was typical for A. mellifera carnica. A. mellifera caucasica COX1 sequence lacked all the above-mentioned sites. We developed a procedure for rapid identification of honey bee subspecies by PCR with restriction fragment length polymorphism (RFLP) using mutagenic primers. The developed molecular method for honey bee subspecies identification is fast and inexpensive. PMID:29382048

  10. Morphological traits of Pacific Flyway Canada Geese as an aid to subspecies identification and management

    Science.gov (United States)

    Pearce, John M.; Bollinger, Karen S.

    2003-01-01

    Subspecies of Canada Geese (Branta canadensis) exhibit wide variation in body size across their range. To monitor harvest levels in the Pacific Flyway, biologists commonly use culmen length and plumage color to differentiate among subspecies on sympatric wintering grounds. Among the four large-bodied Pacific subspecies (B. c. parvipes, B. c. occidentalis, B. c. fulva, and B. c. moffitti), overlap in culmen length and subjectivity of visually assessing color results in misclassification and inaccurate harvest estimates. We examined the morphology of Pacific large-bodied Canada Geese to characterize body size variation among subspecies and provide more discriminatory measures for harvest assessments. We found that culmen length, one of the most commonly used field measures, overlapped widely among subspecies, and it had little support for inclusion in discriminatory models. Morphological measures with greater explanatory power included bill width at nail, bill width at base, head length, and mid wing. If culmen length and plumage color continue to be used to assess winter harvest, we recommend the addition of at least one sex-specific measurement to reduce levels of misclassification among subspecies. If an additional morphological measure is included, further evaluation on the wintering grounds should be conducted as this measure's effectiveness may vary depending upon observer bias, temporal and spatial variation in subspecies abundance, and the proportion of birds accurately sexed by cloacal examination.

  11. Genetic diversity and demography of two endangered captive pronghorn subspecies from the Sonoran Desert

    Science.gov (United States)

    Klimova, Anastasia; Munguia-Vega, Adrian; Hoffman, Joseph I.; Culver, Melanie

    2014-01-01

    Species that have experienced population reduction provide valuable case studies for understanding genetic responses to demographic change. Pronghorn (Antilocapra americana) were once widespread across the North American plains but were subject to drastic population reductions due to overexploitation and habitat fragmentation during the late 19th and early 20th centuries. A. a. peninsularis and A. a. sonoriensis, 2 pronghorn subspecies that inhabit the southern edge of the species' distribution, are almost extinct and now breed almost exclusively in captivity. We therefore sequenced the complete mitochondrial control region and genotyped 18 microsatellite loci in 109 individuals to evaluate the impact of population bottlenecks, captive breeding, small population sizes, and isolation on the genetic composition of captive populations of these 2 subspecies. We found extremely low levels of genetic diversity in both subspecies. The 2 subspecies showed high and significant genetic differentiation, indicating the absence of historic and recent gene flow despite their geographic proximity within the Sonoran Desert. Historical effective population size estimates for the 2 subspecies were inferred to be similar, whereas the Sonoran pronghorn has a contemporary effective size (Ne) more than twice as high as the Peninsular subspecies. Our findings suggest the need for careful genetic management of both subspecies in order to minimize the further loss of genetic variability.

  12. Subspecialized Radiological Reporting Expedites Turnaround Time of Radiology Reports and Increases Productivity.

    Science.gov (United States)

    Stern, Christoph; Boehm, Thomas; Seifert, Burkhardt; Kawel-Boehm, Nadine

    2018-02-15

     To assess the impact of changing from general to subspecialized reporting on turnaround time of radiology reports (TAT), the fraction of radiology reports available within 24 hours (RReporting workflow in our radiology department was changed from general reporting (radiologists report imaging studies of all areas [neuroradiological, abdominal, musculoskeletal imaging et cetera]) to subspecialized reporting (radiologists solely report imaging studies of their subspecialty field [e. g. musculoskeletal]). TAT, Rreporting (January-December 2012) and compared to a 12-month period of subspecialized reporting (April 2014-March 2015) using Mann Whitney U-test, Pearson chi-square test and odds ratios, respectively.  Report TAT decreased from a median of 17:04 hours (h) during general reporting to 3:38 h during subspecialized reporting, resulting in a 4.7-fold improvement (p report being available reporting. Productivity increased from a median of 301 to 376 (reports/full-time radiologist/month) (p = 0.001).  Changing the workflow from general to subspecialized reporting significantly improved the turnaround time of radiology reports, the fraction of radiology reports available within 24 hours and productivity.   · Changing the radiology reporting workflow from general to subspecialized reporting is feasible.. · Implementation of subspecialized reporting yielded significant improvement of radiology report turnaround time.. · Implementation of subspecialized reporting substantially increased the fraction of radiology reports available reporting.. · Stern C, Boehm T, Seifert B et al. Subspecialized Radiological Reporting Expedites Turnaround Time of Radiology Reports and Increases Productivity. Fortschr Röntgenstr 2018; DOI: 10.1055/s-0044-100728. © Georg Thieme Verlag KG Stuttgart · New York.

  13. 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.

  14. Mercury in Nelson's Sparrow Subspecies at Breeding Sites

    Science.gov (United States)

    Winder, Virginia L.; Emslie, Steven D.

    2012-01-01

    Background Mercury is a persistent, biomagnifying contaminant that can cause negative effects on ecosystems. Marshes are often areas of relatively high mercury methylation and bioaccumulation. Nelson's Sparrows (Ammodramus nelsoni) use marsh habitats year-round and have been documented to exhibit tissue mercury concentrations that exceed negative effects thresholds. We sought to further characterize the potential risk of Nelson's Sparrows to mercury exposure by sampling individuals from sites within the range of each of its subspecies. Methodology/Principal Findings From 2009 to 2011, we captured adult Nelson's Sparrows at sites within the breeding range of each subspecies (A. n. nelsoni: Grand Forks and Upham, North Dakota; A. n. alterus: Moosonee, Ontario; and A. n. subvirgatus: Grand Manan Island, New Brunswick) and sampled breast feathers, the first primary feather (P1), and blood for total mercury analysis. Mean blood mercury in nelsoni individuals captured near Grand Forks ranged from 0.84±0.37 to 1.65±1.02 SD ppm among years, between 2.0 and 4.9 times as high as concentrations at the other sites (Pmercury did not vary among sites within a given sampling year (site means ranged from 0.98±0.69 to 2.71±2.93 ppm). Mean P1 mercury in alterus (2.96±1.84 ppm fw) was significantly lower than in any other sampled population (5.25±2.24–6.77±3.51 ppm; P≤0.03). Conclusions/Significance Our study further characterized mercury in Nelson's Sparrows near Grand Forks; we documented localized and potentially harmful mercury concentrations, indicating that this area may represent a biological mercury hotspot. This finding warrants further research to determine if wildlife populations of conservation or recreational interest in this area may be experiencing negative effects due to mercury exposure. We present preliminary conclusions about the risk of each sampled population to mercury exposure. PMID:22384194

  15. 2002-IJBCS-Article-Thierry B C Alavo

    African Journals Online (AJOL)

    hp

    thuringiensis var. israelensis et Bacillus sphaericus sont les plus utilisées pour lutter contre les larves de moustiques. Le nématode ...... Manasherob R, Khasdan V, Cahan R,. Ben-Dov E. 2008. Variations in the mosquito larvicidal activities of toxins from. Bacillus thuringiensis ssp. Israelensis. Environmental Microbiology,.

  16. 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

  17. Campylobacter fetus subspecies: Comparative genomics and prediction of potential virulence targets

    DEFF Research Database (Denmark)

    Ali, Amjad; Soares, Siomar C.; Santos, Anderson R.

    2012-01-01

    The genus Campylobacter contains pathogens causing a wide range of diseases, targeting both humans and animals. Among them, the Campylobacter fetus subspecies fetus and venerealis deserve special attention, as they are the etiological agents of human bacterial gastroenteritis and bovine genital...... campylobacteriosis, respectively. We compare the whole genomes of both subspecies to get insights into genomic architecture, phylogenetic relationships, genome conservation and core virulence factors. Pan-genomic approach was applied to identify the core- and pan-genome for both C. fetus subspecies and members...... of the genus. The C. fetus subspecies conserved (76%) proteome were then analyzed for their subcellular localization and protein functions in biological processes. Furthermore, with pathogenomic strategies, unique candidate regions in the genomes and several potential core-virulence factors were identified...

  18. [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.

  19. 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.

  20. Burial increases seed longevity of two Artemisia tridentata (Asteraceae) subspecies.

    Science.gov (United States)

    Wijayratne, Upekala C; Pyke, David A

    2012-03-01

    Seed longevity and persistence in soil seed banks may be especially important for population persistence in ecosystems where opportunities for seedling establishment and disturbance are unpredictable. The fire regime, an important driver of population dynamics in sagebrush steppe ecosystems, has been altered by exotic annual grass invasion. Soil seed banks may play an active role in postfire recovery of the foundation shrub Artemisia tridentata, yet conditions under which seeds persist are largely unknown. We investigated seed longevity of two Artemisia tridentata subspecies in situ by retrieving seed bags that were placed at varying depths over a 2 yr period. We also sampled naturally dispersed seeds in litter and soil immediately after seed dispersal and before flowering in subsequent seasons to estimate seed persistence. After 24 mo, seeds buried at least 3 cm below the soil surface retained 30-40% viability whereas viability of seeds on the surface and under litter declined to 0 and seeds in the seed bank was highly heterogeneous both spatially and temporally, and attrition varied significantly by region. Our study suggests that Artemisia tridentata has the potential to form a short-term soil seed bank that persists longer than has been commonly assumed, and that burial is necessary for seed longevity. Use of seeding techniques that promote burial of some seeds to aid in formation of a soil seed bank may increase restoration potential.

  1. A multiphasic typing approach to subtype Streptococcus equi subspecies equi.

    Science.gov (United States)

    Lanka, Saraswathi; Borst, Luke B; Patterson, Sheila K; Maddox, Carol W

    2010-11-01

    The objective of the present investigation was to differentiate between strains of Streptococcus equi subspecies equi implicated in abscess formation in vaccinated horses. Streptococcus equi isolates recovered from clinical specimens associated with equine strangles cases submitted to the University of Illinois Veterinary Diagnostic Laboratory were compared with S. equi isolates representing at least 12 lots of a commercial modified live vaccine (MLV) to determine whether the isolates obtained from the abscesses were vaccine or wild type. Genotyping techniques evaluated included enterobacterial repetitive intergenic consensus polymerase chain reaction (PCR), repetitive extragenic palindrome PCR, BOX element PCR, ribotyping, and pulsed-field gel electrophoresis (PFGE). Phenotypic evaluations were performed using the Biolog GP2 Microplate (hereafter, Biolog). In cases where Biolog and PFGE results did not coincide, a single nucleotide polymorphism located in the upstream regulatory region of szp gene was used to identify the S. equi strains. PFGE and Biolog successfully differentiated wild-type S. equi strains isolated from clinical submissions from isolates of the MLV. PFGE genotyping enabled further subtyping of the wild-type strains, whereas Biolog combined with szp sequencing was useful in differentiating the MLV strain from its wild-type progenitor. Deletion of a single guanine residue located in the upstream regulatory region of the szp gene appears to be conserved among vaccine isolates, and shows a 98.5% correlation to Biolog identification. This multiphasic approach can be used to answer specific diagnostic questions pertaining to the source of infection and/or outbreak, or to address quarantine concerns.

  2. Comparative genomics of Clavibacter michiganensis subspecies, pathogens of important agricultural crops.

    Science.gov (United States)

    Tambong, James T

    2017-01-01

    Subspecies of Clavibacter michiganensis are important phytobacterial pathogens causing devastating diseases in several agricultural crops. The genome organizations of these pathogens are poorly understood. Here, the complete genomes of 5 subspecies (C. michiganensis subsp. michiganensis, Cmi; C. michiganensis subsp. sepedonicus, Cms; C. michiganensis subsp. nebraskensis, Cmn; C. michiganensis subsp. insidiosus, Cmi and C. michiganensis subsp. capsici, Cmc) were analyzed. This study assessed the taxonomic position of the subspecies based on 16S rRNA and genome-based DNA homology and concludes that there is ample evidence to elevate some of the subspecies to species-level. Comparative genomics analysis indicated distinct genomic features evident on the DNA structural atlases and annotation features. Based on orthologous gene analysis, about 2300 CDSs are shared across all the subspecies; and Cms showed the highest number of subspecies-specific CDS, most of which are mobile elements suggesting that Cms could be more prone to translocation of foreign genes. Cms and Cmi had the highest number of pseudogenes, an indication of potential degenerating genomes. The stress response factors that may be involved in cold/heat shock, detoxification, oxidative stress, osmoregulation, and carbon utilization are outlined. For example, the wco-cluster encoding for extracellular polysaccharide II is highly conserved while the sucrose-6-phosphate hydrolase that catalyzes the hydrolysis of sucrose-6-phosphate yielding glucose-6-phosphate and fructose is highly divergent. A unique second form of the enzyme is only present in Cmn NCPPB 2581. Also, twenty-eight plasmid-borne CDSs in the other subspecies were found to have homologues in the chromosomal genome of Cmn which is known not to carry plasmids. These CDSs include pathogenesis-related factors such as Endocellulases E1 and Beta-glucosidase. The results presented here provide an insight of the functional organization of the genomes of

  3. 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.

  4. 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.

  5. 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.

  6. Comparison of the Fibronectin-Binding Protein FNE from Streptococcus equi Subspecies equi with FNZ from S. equi Subspecies zooepidemicus Reveals a Major and Conserved Difference

    Science.gov (United States)

    Lindmark, Hans; Nilsson, Martin; Guss, Bengt

    2001-01-01

    The gene fnz from Streptococcus equi subspecies zooepidemicus encodes a cell surface protein that binds fibronectin (Fn). Fifty tested isolates of S. equi subspecies equi all contain DNA sequences with similarity to fnz. This work describes the cloning and sequencing of a gene, designated fne, with similarity to fnz from two S. equi subspecies equi isolates. The DNA sequences were found to be identical in the two strains, and sequence comparison of the fne and fnz genes revealed only minor differences. However, one base deletion was found in the middle of the fne gene and eight base pairs downstream of the altered reading frame there is a stop codon. An Fn-binding protein was purified from the growth medium of a subspecies equi culture. Determination of the NH2-terminal amino acid sequence and molecular mass, as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, revealed that the purified protein is the gene product of the 5′-terminal half of fne. Fn-binding activity has earlier only been found in the COOH-terminal half of FNZ. By the use of a purified recombinant protein containing the NH2 half of FNZ, we provide here evidence that this half of the protein also harbors an Fn-binding domain. PMID:11292736

  7. 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.

  8. Organic Turkey Flocks: A Reservoir of Streptococcus gallolyticus subspecies gallolyticus.

    Directory of Open Access Journals (Sweden)

    Jochen Schulz

    Full Text Available Streptococcus gallolyticus subspecies gallolyticus (S. gallolyticus can colonise the gastrointestinal tract of humans and animals and is known to cause similar infections in both humans and animals. Data about the spread or prevalence in farm animals are missing. In this study, Trypton Soya Agar was modified to a selective medium enabling the isolation and quantification of S. gallolyticus from faecal samples. The bacterium was observed in 82 out of 91 faecal samples obtained from 18 different organic turkey flocks. The prevalence of shedding birds was estimated by the number of positive fresh droppings and reached up to 100% on most farms. Furthermore, for the first time S. gallolyticus was quantified in faeces from poultry flocks. The median of colony forming units (CFU per gramme faeces was 3.6 x 10(5 CFU/g. Typing of one isolate from each positive faecal sample by multilocus sequence typing delivered 24 sequence types (STs. Most of the isolates belonged to the clonal complex CC58. The same STs of this complex were detected in up to six different flocks. Partly, these flocks were located in various regions and stocked with varying breeding lines. Regarding the biochemical profiles of the same STs from different farms, the results did not contradict a spread of specific STs in the organic turkey production. Moreover, checking the pubMLST database revealed that STs found in this study were also found in other animal species and in humans. The high detection rate and the number of S. gallolyticus in turkey faeces indicate that this bacterium probably belongs to the common microbiota of the gastrointestinal tract of turkeys from organic flocks. Furthermore, the findings of this study support the suggestion of a possible interspecies transmission.

  9. 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...

  10. 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

  11. Subspecies distribution and macrolide and fluoroquinolone resistance genetics of Mycobacterium abscessus in Korea.

    Science.gov (United States)

    Kim, J; Sung, H; Park, J-S; Choi, S-H; Shim, T-S; Kim, M-N

    2016-01-01

    Treating Mycobacterium abscessus infections with antimicrobials remains difficult, possibly due to drug resistance. To investigate the subspecies distribution of M. abscessus and its correlation with antibiotic susceptibility and the genetics of antibiotic resistance, focusing on macrolides and fluoroquinolones, in the Republic of Korea. A total of 53 M. abscessus isolates were identified to the subspecies level by sequencing of hsp65 and erm(41). The minimal inhibitory concentrations (MICs) of clarithromycin (CLM) and ciprofloxacin (CFX) were determined using Sensititre™ RAPMYCO plates. The rrl, gyrA and gyrB genes were sequenced to elucidate the molecular mechanisms of macrolide and fluoroquinolone resistance. Isolates included 22 M. abscessus subsp. abscessus and 31 M. abscessus subsp. bolletii. erm(41) sequences showing subspecies-specific deletions and sequence variations in the 28th nucleotide were concordant with inducible CLM resistance; however, mutations in rrl were not detected. Low- and high-level CFX resistance was observed in respectively 19 (35.8%) and 10 (18.9%) of the 53 clinical isolates, regardless of subspecies. However, no non-synonymous mutations were detected in gyrA or gyrB. Sequencing of the erm gene and subspeciation of M. abscessus may be used to predict inducible macrolide susceptibility. Further studies of the relationship between specific mutations in gyrA or gyrB to MIC change are required.

  12. Subspecies genetic assignments of worldwide captive tigers increase conservation value of captive populations.

    Science.gov (United States)

    Luo, Shu-Jin; Johnson, Warren E; Martenson, Janice; Antunes, Agostinho; Martelli, Paolo; Uphyrkina, Olga; Traylor-Holzer, Kathy; Smith, James L D; O'Brien, Stephen J

    2008-04-22

    Tigers (Panthera tigris) are disappearing rapidly from the wild, from over 100,000 in the 1900s to as few as 3000. Javan (P.t. sondaica), Bali (P.t. balica), and Caspian (P.t. virgata) subspecies are extinct, whereas the South China tiger (P.t. amoyensis) persists only in zoos. By contrast, captive tigers are flourishing, with 15,000-20,000 individuals worldwide, outnumbering their wild relatives five to seven times. We assessed subspecies genetic ancestry of 105 captive tigers from 14 countries and regions by using Bayesian analysis and diagnostic genetic markers defined by a prior analysis of 134 voucher tigers of significant genetic distinctiveness. We assigned 49 tigers to one of five subspecies (Bengal P.t. tigris, Sumatran P.t. sumatrae, Indochinese P.t. corbetti, Amur P.t. altaica, and Malayan P.t. jacksoni tigers) and determined 52 had admixed subspecies origins. The tested captive tigers retain appreciable genomic diversity unobserved in their wild counterparts, perhaps a consequence of large population size, century-long introduction of new founders, and managed-breeding strategies to retain genetic variability. Assessment of verified subspecies ancestry offers a powerful tool that, if applied to tigers of uncertain background, may considerably increase the number of purebred tigers suitable for conservation management.

  13. Phylogenomic Analysis Identifies Gene Gains That Define Salmonella enterica Subspecies I

    Science.gov (United States)

    Lienau, E. Kurt; Blazar, Jeffrey M.; Wang, Charles; Brown, Eric W.; Stones, Robert; Musser, Steven; Allard, Marc W.

    2013-01-01

    Comparative methods for analyzing whole genome sequence (WGS) data enable us to assess the genetic information available for reconstructing the evolutionary history of pathogens. We used the comparative approach to determine diagnostic genes for Salmonella enterica subspecies I. S. enterica subsp. I strains are known to infect warm-blooded organisms regularly while its close relatives tend to infect only cold-blooded organisms. We found 71 genes gained by the common ancestor of Salmonella enterica subspecies I and not subsequently lost by any member of this subspecies sequenced to date. These genes included many putative functional phenotypes. Twenty-seven of these genes are found only in Salmonella enterica subspecies I; we designed primers to test these genes for use as diagnostic sequence targets and data mined the NCBI Sequence Read Archive (SRA) database for draft genomes which carried these genes. We found that the sequence specificity and variability of these amplicons can be used to detect and discriminate among 317 different serovars and strains of Salmonella enterica subspecies I. PMID:24204679

  14. 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.

  15. 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

  16. 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.

  17. Rapid and accurate identification of Streptococcus equi subspecies by MALDI-TOF MS

    DEFF Research Database (Denmark)

    Kudirkiene, Egle; Welker, Martin; Knudsen, Nanna Reumert

    2015-01-01

    phenotypic and sequence similarity between three subspecies their discrimination remains difficult. In this study, we aimed to design and validate a novel, Superspectra based, MALDI-TOF MS approach for reliable, rapid and cost-effective identification of SEE and SEZ, the most frequent S. equi subspecies.......3±7.5%). This result may be attributed to the highly clonal population structure of SEE, as opposed to the diversity of SEZ seen in horses. Importantly strains with atypical colony appearance both within SEE and SEZ did not affect correct identification of the strains by MALDI-TOF MS. Atypical colony variants...... are often associated with a higher persistence or virulence of S. equi, thus their correct identification using the current method strengthens its potential use in routine clinical diagnostics. In conclusion, reliable identification of S. equi subspecies was achieved by combining a MALDI-TOF MS method...

  18. Description of a new subspecies, Macrobrachium aemulum madhusoodani (Decapoda: Palaemonidae) from Neyyar River, Kerala, S. India.

    Science.gov (United States)

    Pillai, P M; Unnikrishnan, V

    2013-01-01

    Macrobrachium aemulum madhusoodani, a new subspecies of M. aemulum (Nobili, 1906) is described and illustrated. The distinctive characters of the subspecies are: rostral formula 9-13/2, second pereiopods dissimilar in shape and unequal in size, movable finger of larger second pereiopod with 2 large denticles on the proximal part and 6 weak denticles on distal part. Similar pattern of dentition is present on immovable finger also. In second small pereiopod, fingers stout, equal, unarmed with distinct gap in between when closed. Numerous stiff setae present on cutting edges of fingers. Telson extends beyond the level of the outer lateral spine of the uropodal exopod. Some of the distinctive morphometric and meristic characters of the specimens did not conform to that collected and described from New Caledonia by Nobili (1906) and recorded from India by Jayachandran and Joseph (1988). Since the features cannot be reckoned as mere growth variations, it is described herein as a new subspecies.

  19. Isolation and identification of Mycobacterium avium subspecies silvaticum from a horse.

    Science.gov (United States)

    Chiers, Koen; Deschaght, Pieter; De Baere, Thierry; Dabrowski, Slawomir; Kotlowski, Roman; De Clercq, Dominique; Ducatelle, Richard; Vaneechoutte, Mario

    2012-07-01

    Routine cultivation methods are able to distinguish between isolates of the Mycobacterium avium and the Mycobacterium tuberculosis complex. However, molecular tools are needed to further identify the several subspecies in the M. avium complex, especially for the subspecies avium and silvaticum. A rapid technique using HhaI restriction digestion of a 349 bp amplification product of the 85B antigen (α-antigen) gene was used for the identification of M. avium subsp. silvaticum in a three-year-old gelding presenting with caseous, necrotizing, granulomatous lesions. The result was confirmed by sequencing of the 85B antigen gene. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Genome-Based Reclassification of Fusobacterium nucleatum Subspecies at the Species Level.

    Science.gov (United States)

    Kook, Joong-Ki; Park, Soon-Nang; Lim, Yun Kyong; Cho, Eugene; Jo, Eojin; Roh, Hansung; Shin, Yeseul; Paek, Jayoung; Kim, Hwa-Sook; Kim, Hongik; Shin, Jeong Hwan; Chang, Young-Hyo

    2017-10-01

    Fusobacterium nucleatum is classified as four subspecies, subsp. nucleatum, polymorphum, vincentii, and animalis, based on DNA-DNA hybridization (DDH) patterns, phenotypic characteristics, and/or multilocus sequence analysis (MLSA). The gold standards for classification of bacterial species are DDH and 16S ribosomal RNA gene (16S rDNA) sequence homology. The thresholds of DDH and 16S rDNA similarity for delineation of bacterial species have been suggested to be >70 and 98.65%, respectively. Average nucleotide identity (ANI) and genome-to-genome distance (GGD) analysis based on genome sequences were recently introduced as a replacement for DDH to delineate bacterial species with ANI (95-96%) and GGD (70%) threshold values. In a previous study, F. hwasookii was classified as a new species based on MLSA and DDH results. 16S rDNA similarity between F. hwasookii type strain and F. nucleatum subspecies type strains was higher than that between F. nucleatum subspecies type strains. Therefore, it is possible that the four F. nucleatum subspecies can be classified as Fusobacterium species. In this study, we performed ANI and GGD analyses using the genome sequences of 36 F. nucleatum, five F. hwasookii, and one Fusobacterium periodonticum strain to determine whether the four F. nucleatum subspecies could be classified as species using OrthoANI and ANI web-based softwares provided by ChunLab and Kostas lab, respectively, and GGD calculator offered by German Collection of Microorganisms and Cell Cultures. ANI values calculated from OrthoANI and ANI calculators between the type strains of F. nucleatum subspecies ranged from 89.80 to 92.97 and from 90.40 to 91.90%, respectively. GGD values between the type strains of F. nucleatum subspecies ranged from 42.3 to 46.0%. ANI and GGD values among strains belonging to the same F. nucleatum subspecies, subsp. nucleatum, subsp. polymorphum, subsp. vincentii, and subsp. animalis were >96 and >68.2%, respectively. These results strongly

  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. Descriptions of a new species and subspecies of Halysidota Hübner, [1819] from Mexico (Lepidoptera: Erebidae: Arctiinae)

    OpenAIRE

    Benoît Vincent; Michel Laguerre

    2017-01-01

    A new species and subspecies of the genus Halysidota are described from Mexico and Guadeloupe respectively: Halysidota witti sp. nov. and Halysidota leda guadulpensis ssp. nov. Details of the new species and subspecies descriptions are based upon morphological and molecular characters as well as distributional data.

  6. Structure and amount of genetic variation at minisatellite loci within the subspecies complex of Phoca vitulina (the harbour seal)

    NARCIS (Netherlands)

    Kappe, A.L.; Bijlsma, R.; Osterhaus, ADME; van Delden, W.; van de Zande, L.

    The structure and amount of genetic variation within and between three subspecies of the harbour seal Phoca vitulina was assessed by multilocus DNA fingerprinting. Bandsharing similarity indicates that the subspecies Phoca vitulina richarhsi (Alaska, East Pacific) is clearly separated from the other

  7. Complete mitochondrial genomes of two subspecies (Rhinolophus ferrumequinum nippon and Rhinolophus ferrumequinum tragatus) of the greater horseshoe bat (Chiroptera: Rhinolophidae).

    Science.gov (United States)

    Xiao, Yanhong; Sun, Keping; Feng, Jiang

    2017-01-01

    Rhinolophus ferrumequinum nippon and Rhinolophus ferrumequinum tragatus are two subspecies of Rhinolophus ferrumequinum currently recognized in China. In this study, their mitochondrial genomes were completely sequenced and annotated. Phylogenetic analyses indicated that R. f. nippon has a close relationship with two subspecies of R. ferrumequinum from Korea with 0.1% divergence, which indicated they are synonyms.

  8. Mitochondrial genome diversity and population structure of two western honey bee subspecies in the Republic of South Africa.

    Science.gov (United States)

    Eimanifar, Amin; Kimball, Rebecca T; Braun, Edward L; Ellis, James D

    2018-01-22

    Apis mellifera capensis Eschscholtz and A.m. scutellata Lepeletier are subspecies of western honey bees that are indigenous to the Republic of South Africa (RSA). Both subspecies have invasive potential and are organisms of concern for areas outside their native range, though they are important bees to beekeepers, agriculture, and the environment where they are native. The aim of the present study was to examine genetic differentiation among these subspecies and estimate their phylogenetic relationships using complete mitochondrial genomes sequences. We used 25 individuals that were either assigned to one of the subspecies or designated hybrids using morphometric analyses. Phylogenetic analyses of mitogenome sequences by maximum likelihood (ML) and Bayesian inference identified a monophyletic RSA clade, subdivided into two clades. A haplotype network was consistent with the phylogenetic trees. However, members of both subspecies occurred in both clades, indicating that A.m. capensis and A.m. scutellata are neither reciprocally monophyletic nor do they exhibit paraphyly with one subspecies nested within the other subspecies. Furthermore, no mitogenomic features were diagnostic to either subspecies. All bees analyzed from the RSA expressed a substantial level of haplotype diversity (most samples had unique haplotypes) but limited nucleotide diversity. The number of variable codons across protein-coding genes (PCGs) differed among loci, with CO3 exhibiting the most variation and ATP6 the least.

  9. Descriptions of a new species and subspecies of Halysidota Hübner, [1819] from Mexico (Lepidoptera: Erebidae: Arctiinae

    Directory of Open Access Journals (Sweden)

    Benoît Vincent

    2017-12-01

    Full Text Available A new species and subspecies of the genus Halysidota are described from Mexico and Guadeloupe respectively: Halysidota witti sp. nov. and Halysidota leda guadulpensis ssp. nov. Details of the new species and subspecies descriptions are based upon morphological and molecular characters as well as distributional data.

  10. Controle integrado de espécies de Simulium (Diptera, Simuliidae por Bacillus thuringiensis e manejos mecânicos no riacho e nos vertedouros de tanques de piscicultura, Almirante Tamandaré, Paraná, Brasil Integrated pest control of Simulium (Diptera, Simuliidae with Bacillus thuringiensis and mechanical handling in creek and pisciculture spillway, Almirante Tamandaré, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Fabiane Petry

    2004-03-01

    Full Text Available No Riacho dos Padres na Chácara Evíssima, numa microempresa de agronegócio com criação de peixes e animais domésticos, área de lazer e salão de eventos, localizada na Região Metropolitana de Curitiba, os simulídeos em grande proliferação causaram sério impacto com as picadas a tal ponto que dificultaram o convívio habitual. De janeiro a agosto de 2002, coletou-se 24.021 pupas por meio das quais foram identificadas as espécies: Simulium inaequale, Simulium perflavum, Simulium pertinax com 85,98% e Simulium orbitale, Simulium subnigrum, Simulium distinctum e Simulium incrustatum com somente 14,02% de freqüência. O combate a estas populações iniciado em 28 de fevereiro terminou em 08 de agosto de 2002. O controle integrado consistiu na aplicação de biopesticida Bacillus thuringiensis var. israelensis (Bti e em manejos mecânicos não só removendo os imaturos (ovos, larvas e pupas por meio de escovação de vertedouros, mas também pela retirada de substratos naturais e antrópicos do leito. A densidade larvária média inicial, antes da aplicação de Bti no leito do riacho (75 m e no último vertedouro, verificada em substratos antrópicos fitilhos (área 13.500 cm², foi de 6,7 e 11,5 larvas/cm², respectivamente. Nestes habitats, o controle integrado com Bti de 1,77 a 2,09 mg/litro do ingrediente ativo, suplementado com manejos mecânicos, monitorado em substratos fitilhos (área 20.250 cm², resultou em redução larvar de 72,61% a 99,97% e de 74,91% a 99,45%, respectivamente, nas vazões de 0,39 a 0,45 e de 0,38 a 0,43 m³/min. No primeiro vertedouro (área 5.110 cm², porém, só com manejos mecânicos, atingiu-se a redução larvária de 53,81% a 99,59%. O controle efetuado reduziu as picadas hematófagas ao nível esperado, surtindo o efeito positivo almejado.At Riacho dos Padres, Chácara Evíssima, a small agribusiness venture featuring fish, poultry and cattle farming; a recreation outdoor facility and Event Hall

  11. 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

  12. 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...

  13. 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.

  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. 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)

  1. Mitogenomic phylogenetics of fin whales (Balaenoptera physalus spp.) : Genetic evidence for revision of subspecies

    NARCIS (Netherlands)

    Archer, Frederick I.; Morin, Phillip A.; Hancock-Hanser, Brittany L.; Robertson, Kelly M.; Leslie, Matthew S.; Bérubé, Martine; Panigada, Simone; Taylor, Barbara L.

    2013-01-01

    There are three described subspecies of fin whales (Balaenoptera physalus): B. p. physalus Linnaeus, 1758 in the Northern Hemisphere, B. p. quoyi Fischer, 1829 in the Southern Hemisphere, and a recently described pygmy form, B. p. patachonica Burmeister, 1865. The discrete distribution in the North

  2. Giemsa C-banding Karyotypes of Two Subspecies of Hordeum brevisubulatum from China

    DEFF Research Database (Denmark)

    Linde-Laursen, Ib; Bothmer, R.

    1984-01-01

    C-banding patterns ofH. brevisubulatum subsp.brevisubulatum (2x) and subsp.turkestanicum (4x) had conspicuous telomeric C-bands in at least one chromosome arm with a minor difference in average band size between subspecies. Other conspicuous bands were few in number as in other taxa of the specie...

  3. Detection of Mycobacterium avium subspecies paratuberculosis in Drinking Water and Biofilms Using Quantitative PCR

    Science.gov (United States)

    Mycobacterium avium subspecies paratuberculosis (MAP) causes Johne’s disease in domestic animals and has been implicated in Crohn’s disease in humans. This bacterium is a slow growing, gram-positive, acid-fast organism which can be difficult to culture from the environment. For ...

  4. Multivariate analysis of morphological diversity among closely related Daucus species and subspecies in Tunisia

    Science.gov (United States)

    The genus Daucus includes about 20-25 species worldwide. Northern Africa represents a major center of diversity of Daucus, with Tunisia thought to contain 11 species and seven subspecies. We assessed morphological diversity from a Daucus germplasm collection of 103 accessions at the National Gene Ba...

  5. Subspecies identification of captive Orang Utan in Melaka based on D-loop mitochondria DNA

    Science.gov (United States)

    Kamaluddin, Siti Norsyuhada; Yaakop, Salmah; Idris, Wan Mohd Razi; Rovie-Ryan, Jeffrine Japning; Md-Zain, Badrul Munir

    2018-04-01

    Mitochondrial DNA of Bornean Orang Utan populations suggests that there are three different subspecies (Pongo pygmaeus pygmaeus; Sarawak & Northwest Kalimantan, P. p. wurmbii; Southern West Kalimantan and Central Kalimantan, P. p. morio; East Kalimantan and Sabah). The subspecies of Orang Utans in captivity are difficult to determine through morphological observation. Thus, misidentification by ranger or zoo staffs leads to unwanted consequences especially towards conservation efforts of Orang Utan. The main objective of this study was to identify the subspecies and the geographic origin of 10 Orang Utans in Zoo Melaka and A' Famosa by using partial mitochondrial D-loop gene sequences. DNA of all individuals was extracted from FTA Card. Data analyses were performed using Maximum Parsimony, MP and Neighbor Joining, NJ. Molecular phylogeny analysis revealed that all the samples likely belong to one species of Sumatran Orang Utan (P. abelii) and three different subspecies of Bornean Orang Utans (P. p. pygmaeus, P. p. morio, and P. p. wurmbii). The results obtained in this study indirectly help the management of zoos in term of conservation and visitor's education.

  6. Comparison of the bioluminescence of Photorhabdus species and subspecies type strains

    Czech Academy of Sciences Publication Activity Database

    Hyršl, P.; Číž, Milan; Lojek, Antonín

    2004-01-01

    Roč. 49, č. 5 (2004), s. 539 ISSN 0015-5632 R&D Projects: GA AV ČR IBS5004009 Institutional research plan: CEZ:AV0Z5004920 Keywords : bioluminescence * Photorhabdus species type strains * Photorhabdus subspecies type strains Subject RIV: BO - Biophysics Impact factor: 1.034, year: 2004

  7. Characteristics of an Extensive Mycobacterium avium subspecies paratuberculosis Recombinant Protein Set

    Science.gov (United States)

    In the first step of a comprehensive large-scale antigen discovery project, 651 Mycobacterium avium subspecies paratuberculosis proteins were produced in Escherichia coli. All of these were purified by affinity chromatography, dialyzed in phosphate buffered saline, and analyzed on SDS-PAGE gels. C...

  8. Mycobacterium avium subspecies paratuberculosis recombinant proteins modulate antimycobacterial functions of bovine macrophages

    Science.gov (United States)

    It has been shown that Mycobacterium avium subspecies paratuberculosis (M. paratuberculosis) activates the Mitogen Activated Protein Kinase (MAPK) p38 pathway, yet it is unclear which components of M. paratuberculosis are involved in the process. Therefore, a set of 42 M. paratuberculosis recombinan...

  9. Interest in Providing Multiple Sclerosis Care and Subspecializing in Multiple Sclerosis Among Neurology Residents

    Science.gov (United States)

    Teixeira-Poit, Stephanie; Kane, Heather L.; Frost, A. Corey; Keating, Michael; Olmsted, Murrey

    2014-01-01

    Background: Although detailed knowledge regarding treatment options for multiple sclerosis (MS) patients is largely limited to neurologists, shortages in the neurologist workforce, including MS subspecialists, are predicted. Thus, MS patients may have difficulties in gaining access to appropriate care. No systematic evaluation has yet been performed of the number of neurology residents planning to pursue MS subspecialization. This study identifies factors affecting interest in providing MS patient care or MS subspecialization among current neurology residents. Methods: We randomly selected half of all Accreditation Council of Graduate Medical Education–certified neurology residency programs in the continental United States to receive the neurology resident survey. Completed surveys were received from 218 residents. Results: Residents were significantly more likely to have increased interest in MS care when they participated in MS research, were interested in teaching, and indicated that the “ability to improve patient outcomes and quality of life” was a positive factor influencing their desire to provide MS patient care. Residents who were interested in providing MS care, interested in teaching, and indicated that “research opportunities” was a positive factor for providing MS patient care were significantly more likely to express interest in MS subspecialization. Conclusions: Increasing opportunities to interact with MS patients, learn about MS care, and participate in MS research may increase interest in MS care and subspecialization among neurology residents. Opportunities to educate residents regarding MS patient care may affect residents’ attitudes. PMID:24688352

  10. Streptococcus equi subspecies zooepidemicus Infections in Humans by Zoonotic Transmission from Horses

    Centers for Disease Control (CDC) Podcasts

    2013-06-12

    Dr. Mike Miller reads an abridged version of the Emerging Infectious Diseases’ article, Streptococcus equi subspecies zooepidemicus Infections in Humans by Zoonotic Transmission from Horses.  Created: 6/12/2013 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 7/3/2013.

  11. A new subspecies of Phascolion Theel, 1875 (Sipuncula: Golfingiidae) from Indian waters

    Digital Repository Service at National Institute of Oceanography (India)

    Saiz, J.I.; Bustamante, M.; Tajadura, J.; Vijapure, T.; Sukumaran, S.

    , vol.3931(3); 2015; 433-437 A new subspecies of Phascolion Théel, 1875 (Sipuncula: Golfingiidae) from Indian waters JOSÉ I. SAIZ1, MARIA BUSTAMANTE1, JAVIER TAJADURA1, TEJAL VIJAPURE2 & SONIYA SUKUMARAN2 1 Universidad del País Vasco / EHU, 48080...

  12. Chronological enumeration of nominal species and subspecies of Corydoras (Pisces, Siluriformes, Callichthyidae)

    NARCIS (Netherlands)

    Nijssen, H.; Isbrücker, I.J.H.

    1979-01-01

    A complete list of species and subspecies accepted as members of the genus Corydoras Lacépède, 1803, is given. They are arranged in chronological order. Invalid specific names are followed by their senior synonym. Nomina nuda are listed separately. A bibliography covering all publications containing

  13. Characterizing the molecular variation among American marten (Martes americana) subspecies from Oregon and California

    Science.gov (United States)

    Keith M. Slauson; Bill Zielinski; Karen D. Stone

    2009-01-01

    We investigated the subspecific identity of a rediscovered population of American martens within the range of a presumed extinct subspecies (Martes americana humboldtensis) by comparing mitochondrial DNA sequence diversity from contemporary individuals within the described ranges of M. a. humboldtensis, nearby ranges of

  14. Differentiation of Bifidobacterium longum subspecies longum and infantis by quantitative PCR using functional gene targets

    Directory of Open Access Journals (Sweden)

    Blair Lawley

    2017-05-01

    Full Text Available Background Members of the genus Bifidobacterium are abundant in the feces of babies during the exclusively-milk-diet period of life. Bifidobacterium longum is reported to be a common member of the infant fecal microbiota. However, B. longum is composed of three subspecies, two of which are represented in the bowel microbiota (B. longum subsp. longum; B. longum subsp. infantis. B. longum subspecies are not differentiated in many studies, so that their prevalence and relative abundances are not accurately known. This may largely be due to difficulty in assigning subspecies identity using DNA sequences of 16S rRNA or tuf genes that are commonly used in bacterial taxonomy. Methods We developed a qPCR method targeting the sialidase gene (subsp. infantis and sugar kinase gene (subsp. longum to differentiate the subspecies using specific primers and probes. Specificity of the primers/probes was tested by in silico, pangenomic search, and using DNA from standard cultures of bifidobacterial species. The utility of the method was further examined using DNA from feces that had been collected from infants inhabiting various geographical regions. Results A pangenomic search of the NCBI genomic database showed that the PCR primers/probes targeted only the respective genes of the two subspecies. The primers/probes showed total specificity when tested against DNA extracted from the gold standard strains (type cultures of bifidobacterial species detected in infant feces. Use of the qPCR method with DNA extracted from the feces of infants of different ages, delivery method and nutrition, showed that subsp. infantis was detectable (0–32.4% prevalence in the feces of Australian (n = 90, South-East Asian (n = 24, and Chinese babies (n = 91, but in all cases at low abundance (<0.01–4.6% compared to subsp. longum (0.1–33.7% abundance; 21.4–100% prevalence. Discussion Our qPCR method differentiates B. longum subspecies longum and infantis using

  15. Rapid and accurate identification of Streptococcus equi subspecies by MALDI-TOF MS.

    Science.gov (United States)

    Kudirkiene, Egle; Welker, Martin; Knudsen, Nanna R; Bojesen, Anders M

    2015-07-01

    Streptococcus equi includes very important animal and human pathogens. S. equi subsp. equi (SEE) is a highly pathogenic equine specific subspecies, while S. equi subsp. zooepidemicus (SEZ) and S. equi subsp. ruminatorum are opportunistic pathogens of various animal species and humans. Due to great phenotypic and sequence similarity between three subspecies their discrimination remains difficult. In this study, we aimed to design and validate a novel, Superspectra based, MALDI-TOF MS approach for reliable, rapid and cost-effective identification of SEE and SEZ, the most frequent S. equi subspecies in horses. Superspectra created in this study enabled correct identification of 86 strains belonging to different subspecies of S. equi, isolated from various hosts, infection sites and years. In general, higher average identification accuracy was achieved for SEE (99.0±3.0%) than for SEZ (93.3±7.5%). This result may be attributed to the highly clonal population structure of SEE, as opposed to the diversity of SEZ seen in horses. Importantly strains with atypical colony appearance both within SEE and SEZ did not affect correct identification of the strains by MALDI-TOF MS. Atypical colony variants are often associated with a higher persistence or virulence of S. equi, thus their correct identification using the current method strengthens its potential use in routine clinical diagnostics. In conclusion, reliable identification of S. equi subspecies was achieved by combining a MALDI-TOF MS method with spectra analyses using the SARAMIS database. Additionally, first results on subtyping of SEZ indicated that a more refined discrimination, for example for epidemiological surveys, may be possible. Copyright © 2015 Elsevier GmbH. All rights reserved.

  16. Island Evolution and Systematic Revision of Comoran Snakes: Why and When Subspecies Still Make Sense

    Science.gov (United States)

    Hawlitschek, Oliver; Nagy, Zoltán T.; Glaw, Frank

    2012-01-01

    Species delimitation and species concepts have been a matter of debate among biodiversity researchers in the last decades, resulting in integrative taxonomy approaches and the use of modern species concepts, such as the phylogenetic, evolutionary or general lineage species concepts. The discussion of subspecies status and concepts has been addressed much less extensively, with some researchers completely refraining from recognizing subspecies. However, allopatric insular populations that are particularly differentiated have traditionally been assigned subspecies status. We studied the molecular phylogeny and morphology of endemic Comoran tree snakes of the genus Lycodryas. Taking an integrative taxonomic approach, we used the concept of independent lines of evidence to discriminate between evidence for specific and subspecific status. Molecular (mtDNA) and morphological data provided sufficient evidence to support four different taxa within Comoran Lycodryas. In a revision of this group, we propose two species, each with two subspecies. We present a discussion of the strong sexual dichromatism unique to Comoran Lycodryas within the genus and related genera that may be explained by sexual selection in combination with the absence of major predators. Then, we discuss the effects of insular evolution and the “island rule” on morphological traits in Comoran Lycodryas and in Liophidium mayottensis, another snake endemic to the Comoros. The absence of larger-bodied snakes may have promoted an increase in body size and the number of dorsal scale rows in these species. Finally, we discuss the subspecies concept, its applications and its significance for integrative taxonomy and for limiting taxonomic inflation. We emphasize that taxon descriptions should be based on an integrative approach using several lines of evidence, preferably in combination with statements on the underlying species concepts or operational criteria, to increase the objectivity and comparability

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Bacteraemia due to Streptococcus gallolyticus subspecies pasteurianus is associated with digestive tract malignancies and resistance to macrolides and clindamycin.

    Science.gov (United States)

    Sheng, Wang-Huei; Chuang, Yu-Chung; Teng, Lee-Jene; Hsueh, Po-Ren

    2014-08-01

    This study was intended to delineate the association between digestive tract malignancies and bacteraemia due to Streptococcus gallolyticus subspecies pasteurianus. We reviewed the medical records and microbiological results of patients with bacteraemia due to Streptococcus bovis during the period 2000-2012. Species and subspecies identification of isolates originally classified as S. bovis was confirmed by 16S rRNA sequencing and PCR restriction fragment length polymorphism (PCR-RFLP) assays. Minimum inhibitory concentrations of antimicrobial agents were determined by the broth microdilution method. Of the 172 S. bovis complex isolates obtained from 172 patients (age range, Streptococcus infantarius. The majority (n = 104, 60%) of patients were male and had underlying malignancies (n = 87, 51%). Bacteraemia due to S. gallolyticus subspecies gallolyticus was significantly associated with endocarditis while S. gallolyticus subspecies pasteurianus was more likely to be associated with malignancies of the digestive tract, including gastric, pancreatic, hepatobiliary and colorectal cancers. Septic shock at presentation was the only factor associated with mortality among patients with bacteraemia due to either subspecies of S. bovis. Isolates of S. gallolyticus subspecies pasteurianus had higher rates of resistance to macrolides and clindamycin than isolates of S. gallolyticus subspecies gallolyticus. Extensive diagnostic work-up for digestive tract malignancies and trans-esophageal echocardiogram should be investigated in patients with bacteraemia caused by S. gallolyticus. Copyright © 2014 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  5. COMPLEXES OF BISCITRATOGERMANATES AND BISCITRATOSTANATES WITH METALS ARE MODIFIERS OF ACTIVITY OF Bacillus thuringiensis var. іsraelensis PEPTIDASES AND α-Penicillium canescens, Cladosporium cladosporioides AND Aspergillus niger GALACTOIDASES

    Directory of Open Access Journals (Sweden)

    L. D. Varbanets

    2016-06-01

    Full Text Available The aim of the research was to study the effect of a number of coordination compounds of stanum and germanium (compounds 1‒8 as modifiers of activity of peptidases and α-galactosidases. The coordination compounds with the same type structure of were investigated as enzymes effectors. Two types of complexes: 1 [M(H2O6][Ge(НCitr2]4H2O (M = Mg(1, Mn(2, Co(3, Ni(4, Zn(5, containing biscitrate-stanate anion ([Ge(НCitr2]2-, and 2 [M(H2O6][Sn(НCitr2]4H2O (M = Mg(6, Co(7, Ni(8, containing biscitratostanate anion and various hexaaquacations ([M(H2O6]2+, М= Mg, Mn, Co, Ni, Zn were studied. It is shown that the compound 6 which is a biscitratostanate complex containing magnesium ions as metal, can be used for stimulation on 20‒25% of collagenase activity of B. thuringiensis var. israelensis IMV B-7465 peptidase 1 and peptidase 2. Compound 1 (biscitrate-stanate complex containing magnesium ions as metal and 7 (biscitratostanate complex containing cobalt ions as metal and compound 6 in a concentration of 0.001% are able to increase elastolytic activity of peptidase 1 on 55‒58%. However compound 7 has shown the greatest activating effect. It increased the elastolytic activity of peptidase 2 on 100‒140% (for both tested concentrations. This indicates that the compound 7 can further be used as of peptidase 2 elastolytic activity effector. In the study of effect of the considered coordination compounds on the activity of α-galactosidase of Penicillium canescens, Cladosporium cladosporioides and Aspergillus niger was found that when using a number of complexes (1‒2 and 4‒8, there is a slight increase on 12‒20% of enzyme activity of P. canescens, and the maximum effect (~20%, concentration 0.01% was provided by complex 6.

  6. Characterisation of Indica Special Protein (ISP), a marker protein for the differentiation of Oryza sativa subspecies indica and japonica.

    Science.gov (United States)

    Zhu, Keming; Min, Chao; Xia, Hengchuan; Yang, Yanhua; Wang, Bin; Chen, Keping

    2014-04-29

    Based on both morphological and physiological traits, Asian cultivated rice (Oryza sativa L.) can be classified into two distinct subspecies, indica and japonica. To better understand the differences between the two subspecies, a proteomic approach was used to profile proteins present in the yellow seedling stage of 10 indica and 10 japonica rice varieties. We report the discovery of a new protein, Indica Special Protein (ISP), which was only detected in yellow seedlings of indica varieties, and was absent from japonica varieties. Hence, ISP may represent a key gene for the differentiation of indica and japonica subspecies.

  7. Characterisation of Indica Special Protein (ISP, a Marker Protein for the Differentiation of Oryza sativa Subspecies indica and japonica

    Directory of Open Access Journals (Sweden)

    Keming Zhu

    2014-04-01

    Full Text Available Based on both morphological and physiological traits, Asian cultivated rice (Oryza sativa L. can be classified into two distinct subspecies, indica and japonica. To better understand the differences between the two subspecies, a proteomic approach was used to profile proteins present in the yellow seedling stage of 10 indica and 10 japonica rice varieties. We report the discovery of a new protein, Indica Special Protein (ISP, which was only detected in yellow seedlings of indica varieties, and was absent from japonica varieties. Hence, ISP may represent a key gene for the differentiation of indica and japonica subspecies.

  8. Fusobacterium nucleatum subspecies identification by matrix-assisted laser desorption ionization-time of flight mass spectrometry.

    Science.gov (United States)

    Nie, Shuping; Tian, Baoyu; Wang, Xiaowei; Pincus, David H; Welker, Martin; Gilhuley, Kathleen; Lu, Xuedong; Han, Yiping W; Tang, Yi-Wei

    2015-04-01

    We explored the use of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for identification of Fusobacterium nucleatum subspecies. MALDI-TOF MS spectra of five F. nucleatum subspecies (animalis, fusiforme, nucleatum, polymorphum, and vincentii) were analyzed and divided into four distinct clusters, including subsp. animalis, nucleatum, polymorphum, and fusiforme/vincentii. MALDI-TOF MS with the modified SARAMIS database further correctly identified 28 of 34 F. nucleatum clinical isolates to the subspecies level. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  9. 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.

  10. 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.

  11. 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...

  12. 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.

  13. Full genome sequence of a Danish isolate of Mycobacterium avium subspecies paratuberculosis, strain Ejlskov2007

    DEFF Research Database (Denmark)

    Afzal, Mamuna; Abidi, Soad; Mikkelsen, Heidi

    We have sequenced a Danish isolate of Mycobacterium avium subspecies paratuberculosis, strain Ejlskov2007. The strain was isolated from faecal material of a 48 month old second parity Danish Holstein cow, with clinical symptoms of chronic diarrhoea and emaciation. The cultures were grown on Löwen......We have sequenced a Danish isolate of Mycobacterium avium subspecies paratuberculosis, strain Ejlskov2007. The strain was isolated from faecal material of a 48 month old second parity Danish Holstein cow, with clinical symptoms of chronic diarrhoea and emaciation. The cultures were grown......, consisting of 4317 unique gene families. Comparison with M. avium paratuberculosis strain K10 revealed only 3436 genes in common (~70%). We have used GenomeAtlases to show conserved (and unique) regions along the Ejlskov2007 chromosome, compared to 2 other Mycobacterium avium sequenced genomes. Pan......-genome analyses of the sequenced Mycobacterium genomes reveal a surprisingly open and diverse set of genes for this bacterial genera....

  14. [Prokaryotic expression and immunogenicity of IgG-binding protein of Streptococcus equi subspecies equi].

    Science.gov (United States)

    Shao, Jungao; Jiang, Huijiao; Chang, Jianxin; Zhang, Baojiang; Li, Shanchun; Su, Yan

    2016-05-25

    To analyze the immunogenicity and protective ability of recombinant IgG-binding protein (EAG) of Streptococcus equi subspecies equi and to evaluate its value when used as equine vaccine antigen, EAG gene was amplified by PCR and inserted into pET-28a vector. The EAG recombinant proteins were expressed and purified to immune mice. The serum antibody and challenge protection were tested. The purified recombinant protein of EAG was 26 kDa, and the protein reacted specifically with positive serum of Streptococcus equi subspecies equi. The mice antibody level for EAG immunization group was 1∶8 100. The immunological protection result showed that the protection rate of the EAG recombinant protein was 90%. The results suggested that the EAG protein has good immunogenicity and immunological protection, and it can effectively increase the humoral immune response and immunological protection of mice.

  15. Inference of purifying and positive selection in three subspecies of chimpanzees (Pan troglodytes) from exome sequencing

    DEFF Research Database (Denmark)

    Bataillon, Thomas; Duan, Jinjie; Hvilsom, Christina

    2015-01-01

    of recent gene flow from Western into Eastern chimpanzees. The striking contrast in X-linked vs. autosomal polymorphism and divergence previously reported in Central chimpanzees is also found in Eastern and Western chimpanzees. We show that the direction of selection (DoS) statistic exhibits a strong non......-monotonic relationship with the strength of purifying selection S, making it inappropriate for estimating S. We instead use counts in synonymous vs. non-synonymous frequency classes to infer the distribution of S coefficients acting on non-synonymous mutations in each subspecies. The strength of purifying selection we...... infer is congruent with the differences in effective sizes of each subspecies: Central chimpanzees are undergoing the strongest purifying selection followed by Eastern and Western chimpanzees. Coding indels show stronger selection against indels changing the reading frame than observed in human...

  16. Clarifying the Dioscorea buchananii Benth. species complex: a new potentially extinct subspecies for South Africa

    Science.gov (United States)

    Wilkin, Paul; Muasya, A. Muthama

    2015-01-01

    Abstract The Dioscorea buchananii complex is shown to comprise three species, one of which is divided into two subspecies, based on morphological data. Two species, Dioscorea rupicola Kunth and Dioscorea multiloba Kunth, are endemic or subendemic to South Africa and of widespread occurrence in KwaZulu Natal. They differ markedly from each other in inflorescence and floral morphology and appear to be ecologically differentiated. The third species, Dioscorea buchananii Benth., is primarily found in southeastern tropical Africa, but a small number of specimens collected in South Africa in the late 19th and early 20th centuries are placed in an endemic subspecies, Dioscorea buchananii subsp. undatiloba (Baker) Wilkin. The latter taxon is a high priority in terms of rediscovery and conservation. Keys, descriptions, supporting information and illustrations are provided and made available online through eMonocot biodiversity informatics tools. Three nomenclatural acts are undertaken: two names are placed in synonymy and a new combination made. PMID:25931973

  17. Genetic Relationship among Three Subspecies of Oncorhynchus masou Determined by Mitochondrial DNA Sequence Analysis

    OpenAIRE

    Ichiro, Oohara; Toshio, Okazaki; National Research Institute of Aquaculture; National Research Institute of Aquaculture

    1996-01-01

    It is generally accepted that there are 3 subspecies of Oncorhynchus masou in Japan, namely, Masu salmon (Oncorhynchus masou masou (Brevoort)), Amago salmon (O. masou ishikawae Jordan & McGregor), and Biwa salmon (O. masou rhodurus Jordan & McGregor or O. masou subsp. Kimura). Since the genetic relationship of these three taxa is not well known, there has been considerable confusion over their nomenclature. We have clarified the genetic relationship among these three taxa by partially sequenc...

  18. A new subspecies of sea snake, Hydrophis platurus xanthos, from Golfo Dulce, Costa Rica

    OpenAIRE

    Bessesen,Brooke; Galbreath,Gary

    2017-01-01

    We describe a distinctive new subspecies of sea snake from the occasionally anoxic inner-basin waters of Golfo Dulce, Costa Rica, based on combined data garnered between 2010 and 2017 for 154 specimens, 123 free-ranging and 31 museum-held. The yellow sea snake, Hydrophis platurus xanthos Bessesen & Galbreath, subsp. n., is diagnosed by a notably smaller body size and nearly uniform yellow coloration, which contrasts with the black and yellow striae and tail spots or bands typical of t...

  19. A genetic comparison of two alleged subspecies of Philippine cynomolgus macaques.

    Science.gov (United States)

    Smith, David Glenn; Ng, Jillian; George, Debra; Trask, Jessica Satkoski; Houghton, Paul; Singh, Balbir; Villano, Jason; Kanthaswamy, Sreetharan

    2014-09-01

    Two subspecies of cynomolgus macaques (Macaca fascicularis) are alleged to co-exist in the Philippines, M. f. philippensis in the north and M. f. fascicularis in the south. However, genetic differences between the cynomolgus macaques in the two regions have never been studied to document the propriety of their subspecies status. We genotyped samples of cynomolgus macaques from Batangas in southwestern Luzon and Zamboanga in southwestern Mindanao for 15 short tandem repeat (STR) loci and sequenced an 835 bp fragment of the mtDNA of these animals. The STR genotypes were compared with those of cynomolgus macaques from southern Sumatra, Singapore, Mauritius and Cambodia, and the mtDNA sequences of both Philippine populations were compared with those of cynomolgus macaques from southern Sumatra, Indonesia and Sarawak, Malaysia. We conducted STRUCTURE and PCA analyses based on the STRs and constructed a median joining network based on the mtDNA sequences. The Philippine population from Batangas exhibited much less genetic diversity and greater genetic divergence from all other populations, including the Philippine population from Zamboanga. Sequences from both Batangas and Zamboanga were most closely related to two different mtDNA haplotypes from Sarawak from which they are apparently derived. Those from Zamboanga were more recently derived than those from Batangas, consistent with their later arrival in the Philippines. However, clustering analyses do not support a sufficient genetic distinction of cynomolgus macaques from Batangas from other regional populations assigned to subspecies M. f. fascicularis to warrant the subspecies distinction M. f. philippensis. © 2014 Wiley Periodicals, Inc.

  20. MORPHOLOGICAL AND ANATOMICAL STUDY ON ENDEMIC CROCUS OLIVIERI GAY SUBSP. ISTANBULENSIS MATHEW SUBSPECIES (IRIDACEAE

    Directory of Open Access Journals (Sweden)

    Kadriye Yetişen

    2013-02-01

    Full Text Available In this study, morphological and anatomical properties of Crocus olivieri Gay subsp. istanbulensis Mathew were investigated. Cross-sections of root, scape and leaf parts of the plant were examined anddemonstrated by photographs. Most of the anatomical properties are similar to the other member of Iridaceae family. Sclerenchyma groups were observed around to leaf vascular bundle. Morphological and anatomical findings compared with other two subspecies of Crocus olivieri.

  1. Brain xanthophyll content and exploratory gene expression analysis: subspecies differences in rhesus macaque

    OpenAIRE

    Mohn, Emily S.; Erdman, John W.; Neuringer, Martha; Kuchan, Matthew J.; Johnson, Elizabeth J.

    2017-01-01

    Background The dietary xanthophylls, lutein and zeaxanthin, accumulate in primate retina and brain, and emerging evidence indicates neural lutein content may be beneficial for cognition. Neural xanthophyll content in primates varies greatly among individuals, and genetic factors are likely to be significant contributors. Subspecies of rhesus macaques originating from different geographic locations are known to differ genetically, but the effect of origin on gene expression and carotenoid stat...

  2. A new subspecies of Celastrus (Celastraceae from the Palni hills of South India

    Directory of Open Access Journals (Sweden)

    S. John Britto

    2017-08-01

    Full Text Available Celastrus paniculatus Willd. ssp. angladeanus S.J. Britto, B. Mani and S. Thomas new subspecies from the Palni hills, Western Ghats of Tamilnadu, South India is described and illustrated. The new ssp. is similar to Celastrus paniculatus ssp. aggregatus but differs in flame-coloured branchlets, terminal, erect and stiff panicles exceeding leaves, prominent gibbous and oblique capsules, flowers polygamous but predominantly pistillate and 3-seeded capsules.

  3. 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...

  4. 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

  5. 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...

  6. 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

  7. 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

  8. 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

  9. 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...

  10. 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...

  11. 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

  12. 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...

  13. 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

  14. 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...

  15. 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

  16. 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

  17. 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.

  18. 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.

  19. 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.

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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.

  5. 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

  6. 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.

  7. 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 ...

  8. 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 ...

  9. Molecular genetic divergence of orang utan (Pongo pygmaeus) subspecies based on isozyme and two-dimensional gel electrophoresis.

    Science.gov (United States)

    Janczewski, D N; Goldman, D; O'Brien, S J

    1990-01-01

    The orang utan (Pongo pygmaeus), as currently recognized, includes two geographically separated subspecies: Pongo pygmaeus pygmaeus, which resides on Borneo, and P. p. abelii, which inhabits Sumatra. At present, there is no known route of gene flow between the two populations except through captive individuals which have been released back into the wild over the last several decades. The two subspecies are differentiated by morphological and behavioral characters, and they can be distinguished by a subspecies specific pericentric chromosomal inversion. Nei-genetic distances were estimated between orang utan subspecies, gorilla, chimpanzee and humans using 44 isozyme loci and using 458 soluble fibroblast proteins which were resolved by two-dimensional gel electrophoresis. Phenetic analysis of both data sets supports the following conclusions: the orang utan subspecies distances are approximately 10 times closer to each other than they are to the African apes, and the orang utan subspecies are approximately as divergent as are the two chimpanzee species. Comparison of the genetic distances to genetic distance estimates done in the same laboratory under identical conditions reveals that the distance between Bornean vs. Sumatran orang utans is 5-10 times the distance measured between several pairs of subspecies including lions, cheetahs, and tigers. Near species level molecular genetic distances between orang utan subspecies would support the separate management of Bornean and Sumatran orang utans as evolutionary significant units (Ryder 1987). Evolutionary topologies were constructed from the distance data using both cladistic and phenetic methods. The majority of resulting trees affirmed previous molecular evolutionary studies that indicated that man and chimpanzee diverged from a common ancestor subsequent to the divergence of gorilla from the common ancestor.

  10. Redescription of Gammarus pseudosyriacus (Karaman & Pinkster, 1977) and description of a new subspecies from southern Iran (Crustacea, Amphipoda, Gammaridae).

    Science.gov (United States)

    Semsar-Kazerooni, Maryam; Zamanpoore, Mehrdad; Sadeghi, Saber

    2016-01-01

    The present study focused on redescription of Gammarus pseudosyriacus (Karaman & Pinkster, 1977) based on new materials from Zagros Mountains and describes a new subspecies of freshwater amphipod, Gammarus pseudosyriacus issatisi subsp. n., from the southern Zagros Mountains. The work is based on morphological and morphometric comparisons. This new subspecies has features similar to Gammarus pseudosyriacus. The distinct features that distinguish Gammarus pseudosyriacus issatisi subsp. n. from Gammarus pseudosyriacus are the smaller eyes, shorter body length, and shorter flagellum of antenna 1 and 2.

  11. Mitogenomic phylogenetics of fin whales (Balaenoptera physalus spp.: genetic evidence for revision of subspecies.

    Directory of Open Access Journals (Sweden)

    Frederick I Archer

    Full Text Available There are three described subspecies of fin whales (Balaenoptera physalus: B. p. physalus Linnaeus, 1758 in the Northern Hemisphere, B. p. quoyi Fischer, 1829 in the Southern Hemisphere, and a recently described pygmy form, B. p. patachonica Burmeister, 1865. The discrete distribution in the North Pacific and North Atlantic raises the question of whether a single Northern Hemisphere subspecies is valid. We assess phylogenetic patterns using ~16 K base pairs of the complete mitogenome for 154 fin whales from the North Pacific, North Atlantic--including the Mediterranean Sea--and Southern Hemisphere. A Bayesian tree of the resulting 136 haplotypes revealed several well-supported clades representing each ocean basin, with no haplotypes shared among ocean basins. The North Atlantic haplotypes (n = 12 form a sister clade to those from the Southern Hemisphere (n = 42. The estimated time to most recent common ancestor (TMRCA for this Atlantic/Southern Hemisphere clade and 81 of the 97 samples from the North Pacific was approximately 2 Ma. 14 of the remaining North Pacific samples formed a well-supported clade within the Southern Hemisphere. The TMRCA for this node suggests that at least one female from the Southern Hemisphere immigrated to the North Pacific approximately 0.37 Ma. These results provide strong evidence that North Pacific and North Atlantic fin whales should not be considered the same subspecies, and suggest the need for revision of the global taxonomy of the species.

  12. A morphological review of subspecies of the Asian box turtle, Cuora amboinensis (Testudines, Geomydidae)

    Science.gov (United States)

    Ernst, Carl H.; Laemmerzahl, Arndt F.; Lovich, Jeffrey E.

    2016-01-01

    The turtle Cuora amboinensis has an extensive distribution covering most of southern mainland Asia, Indonesia, and extending to the Philippine Islands. Unlike many species, C. amboinensis occurs on both sides of Wallace's Line separating Asian and Australian flora and fauna. Four subspecies are currently recognized; Cuora a. kamaroma (southern continental Asia, Java and the northern Philippines [introduced]), C. a. lineata (Kachin Province, Myanmar [Burma] and adjacent Yunnan Province, China), C. a. couro (Sumatra, Java, Sumbawa, and adjacent smaller Indonesian islands); and C. a. amboinensis (Moluccas, Sulawesi, Philippines). Five pattern and 33 morphological characters were examined for variation in 691 individuals from throughout the species' range. Our analyses suggest that only two presently recognized subspecies are valid: amboinensis andkamaroma. Neither couro nor lineata are supported by our analysis. We recommend that C. a. couroshould be synonymized with the species C. amboinensis and C. a. lineata with the subspecies C. a. kamaroma.

  13. Ecotype evolution in Glossina palpalis subspecies, major vectors of sleeping sickness.

    Directory of Open Access Journals (Sweden)

    Thierry De Meeûs

    2015-03-01

    Full Text Available The role of environmental factors in driving adaptive trajectories of living organisms is still being debated. This is even more important to understand when dealing with important neglected diseases and their vectors.In this paper, we analysed genetic divergence, computed from seven microsatellite loci, of 614 tsetse flies (Glossina palpalis gambiensis and Glossina palpalis palpalis, major vectors of animal and human trypanosomes from 28 sites of West and Central Africa. We found that the two subspecies are so divergent that they deserve the species status. Controlling for geographic and time distances that separate these samples, which have a significant effect, we found that G. p. gambiensis from different landscapes (Niayes of Senegal, savannah and coastal environments were significantly genetically different and thus represent different ecotypes or subspecies. We also confirm that G. p. palpalis from Ivory Coast, Cameroon and DRC are strongly divergent.These results provide an opportunity to examine whether new tsetse fly ecotypes might display different behaviour, dispersal patterns, host preferences and vectorial capacities. This work also urges a revision of taxonomic status of Glossina palpalis subspecies and highlights again how fast ecological divergence can be, especially in host-parasite-vector systems.

  14. Chimpanzee subspecies and ‘robust’ australopithecine holotypes, in the context of comments by Darwin

    Directory of Open Access Journals (Sweden)

    S. Prat

    2010-02-01

    Full Text Available On the basis of comparative anatomy (including chimpanzees, gorillas and other primates, Darwin1 suggested that Africa was the continent from which ‘progenitors’ of humankind evolved. Hominin fossils from this continent proved him correct. We present the results of morphometric analyses based on cranial data obtained from chimpanzee taxa currently recognised as distinct subspecies, namely Pan troglodytes troglodytes and Pan troglodytes schweinfurthii, as well as Pan paniscus (bonobo. Our objective was to use a morphometric technique2 to quantify the degree of similarity between pairs of specimens, in the context of a statistical (probabilistic definition of a species.3–5 Results obtained from great apes, including two subspecies of chimpanzee, were assessed in relation to same-scale comparisons between the holotypes of ‘robust’ australopithecine (Plio-Pleistocene hominin taxa which have traditionally been distinguished at a species level, notably Paranthropus robustus from South Africa, and Paranthropus (Australopithecus/ Zinjanthropus boisei from East Africa. The question arises as to whether the holotypes of these two taxa, TM 1517 from Kromdraai6 and OH 5 from Olduvai,7 respectively, are different at the subspecies rather than at the species level.

  15. POPULATION STRUCTURE AND HOST USE IN HYBRIDIZING SUBSPECIES OF PAPILIO GLAUCUS (LEPIDOPTERA: PAPILIONIDAE).

    Science.gov (United States)

    Hagen, Robert H

    1990-12-01

    Two parapatric subspecies of the eastern tiger swallowtail butterfly, Papilio glaucus glaucus and P. g. canadensis, differ greatly in larval survival and growth on host plants in the Magnoliaceae, Salicaceae, and Betulaceae. In the first part of this study, butterflies were collected from 17 sites along a transect from Georgia to Quebec and used for allozyme electrophoresis. Two X- (or Z-)linked enzyme loci (Ldh and Pgd) showed allele frequency differences that delineated a hybrid zone between the subspecies in northern Pennsylvania and south-central New York. No significant linkage disequilibrium could be detected among allozyme loci within the hybrid zone samples. Genetic differentiation at Ldh and Pgd coincides with subspecies differences in diapause control and female mimicry, which are also sex-linked. Larval offspring of butterflies from 13 of the sites were then tested in the laboratory for survival and growth on Liriodendron tulipifera (Magnoliaceae), Populus deltoïdes (Salicaceae) and Betula lutea (Betulaceae). Steep clines in survival rates matched the position of the hybrid zone. Hybrid zone larvae showed intermediate survival rates and significant heterogeneity among families on all three plants, indicating presence of substantial genetic variation. The results suggest that differential host use by P. g. glaucus and P. g. canadensis is maintained primarily by independent clines in selection intensity for ability to use allopatric sets of host plants, coupled with restricted gene flow across the hybrid zone. © 1990 The Society for the Study of Evolution.

  16. Genome comparison of Candida orthopsilosis clinical strains reveals the existence of hybrids between two distinct subspecies.

    Science.gov (United States)

    Pryszcz, Leszek P; Németh, Tibor; Gácser, Attila; Gabaldón, Toni

    2014-05-01

    The Candida parapsilosis species complex comprises a group of emerging human pathogens of varying virulence. This complex was recently subdivided into three different species: C. parapsilosis sensu stricto, C. metapsilosis, and C. orthopsilosis. Within the latter, at least two clearly distinct subspecies seem to be present among clinical isolates (Type 1 and Type 2). To gain insight into the genomic differences between these subspecies, we undertook the sequencing of a clinical isolate classified as Type 1 and compared it with the available sequence of a Type 2 clinical strain. Unexpectedly, the analysis of the newly sequenced strain revealed a highly heterozygous genome, which we show to be the consequence of a hybridization event between both identified subspecies. This implicitly suggests that C. orthopsilosis is able to mate, a so-far unanswered question. The resulting hybrid shows a chimeric genome that maintains a similar gene dosage from both parental lineages and displays ongoing loss of heterozygosity. Several of the differences found between the gene content in both strains relate to virulent-related families, with the hybrid strain presenting a higher copy number of genes coding for efflux pumps or secreted lipases. Remarkably, two clinical strains isolated from distant geographical locations (Texas and Singapore) are descendants of the same hybrid line, raising the intriguing possibility of a relationship between the hybridization event and the global spread of a virulent clone.

  17. 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

  18. Building a DNA Barcode Reference Library for the True Butterflies (Lepidoptera) of Peninsula Malaysia: What about the Subspecies?

    Science.gov (United States)

    Wilson, John-James; Sing, Kong-Wah; Sofian-Azirun, Mohd

    2013-01-01

    The objective of this study was to build a DNA barcode reference library for the true butterflies of Peninsula Malaysia and assess the value of attaching subspecies names to DNA barcode records. A new DNA barcode library was constructed with butterflies from the Museum of Zoology, University of Malaya collection. The library was analysed in conjunction with publicly available DNA barcodes from other Asia-Pacific localities to test the ability of the DNA barcodes to discriminate species and subspecies. Analyses confirmed the capacity of the new DNA barcode reference library to distinguish the vast majority of species (92%) and revealed that most subspecies possessed unique DNA barcodes (84%). In some cases conspecific subspecies exhibited genetic distances between their DNA barcodes that are typically seen between species, and these were often taxa that have previously been regarded as full species. Subspecies designations as shorthand for geographically and morphologically differentiated groups provide a useful heuristic for assessing how such groups correlate with clustering patterns of DNA barcodes, especially as the number of DNA barcodes per species in reference libraries increases. Our study demonstrates the value in attaching subspecies names to DNA barcode records as they can reveal a history of taxonomic concepts and expose important units of biodiversity. PMID:24282514

  19. 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.

  20. 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

  1. 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...

  2. 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

  3. [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.

  4. 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...

  5. 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 ...

  6. 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...

  7. 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...

  8. 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...

  9. Threatened and endangered subspecies with vulnerable ecological traits also have high susceptibility to sea level rise and habitat fragmentation.

    Directory of Open Access Journals (Sweden)

    Allison M Benscoter

    Full Text Available The presence of multiple interacting threats to biodiversity and the increasing rate of species extinction make it critical to prioritize management efforts on species and communities that maximize conservation success. We implemented a multi-step approach that coupled vulnerability assessments evaluating threats to Florida taxa such as climate change, sea-level rise, and habitat fragmentation with in-depth literature surveys of taxon-specific ecological traits. The vulnerability, adaptive capacity, and ecological traits of 12 threatened and endangered subspecies were compared to non-listed subspecies of the same parent species. Overall, the threatened and endangered subspecies showed high vulnerability and low adaptive capacity, in particular to sea level rise and habitat fragmentation. They also exhibited larger home ranges and greater dispersal limitation compared to non-endangered subspecies, which may inhibit their ability to track changing climate in fragmented landscapes. There was evidence for lower reproductive capacity in some of the threatened or endangered taxa, but not for most. Taxa located in the Florida Keys or in other low coastal areas were most vulnerable to sea level rise, and also showed low levels of adaptive capacity, indicating they may have a lower probability of conservation success. Our analysis of at-risk subspecies and closely related non-endangered subspecies demonstrates that ecological traits help to explain observed differences in vulnerability and adaptive capacity. This study points to the importance of assessing the relative contributions of multiple threats and evaluating conservation value at the species (or subspecies level when resources are limited and several factors affect conservation success.

  10. Threatened and endangered subspecies with vulnerable ecological traits Also have high susceptibility to sea level rise and habitat fragmentation

    Science.gov (United States)

    Benscoter, Allison M.; Reece, Joshua S.; Noss, Reed F.; Brandt, Laura B.; Mazzotti, Frank J.; Romañach, Stephanie S.; Watling, James I.

    2013-01-01

    The presence of multiple interacting threats to biodiversity and the increasing rate of species extinction make it critical to prioritize management efforts on species and communities that maximize conservation success. We implemented a multi-step approach that coupled vulnerability assessments evaluating threats to Florida taxa such as climate change, sea-level rise, and habitat fragmentation with in-depth literature surveys of taxon-specific ecological traits. The vulnerability, adaptive capacity, and ecological traits of 12 threatened and endangered subspecies were compared to non-listed subspecies of the same parent species. Overall, the threatened and endangered subspecies showed high vulnerability and low adaptive capacity, in particular to sea level rise and habitat fragmentation. They also exhibited larger home ranges and greater dispersal limitation compared to non-endangered subspecies, which may inhibit their ability to track changing climate in fragmented landscapes. There was evidence for lower reproductive capacity in some of the threatened or endangered taxa, but not for most. Taxa located in the Florida Keys or in other low coastal areas were most vulnerable to sea level rise, and also showed low levels of adaptive capacity, indicating they may have a lower probability of conservation success. Our analysis of at-risk subspecies and closely related non-endangered subspecies demonstrates that ecological traits help to explain observed differences in vulnerability and adaptive capacity. This study points to the importance of assessing the relative contributions of multiple threats and evaluating conservation value at the species (or subspecies) level when resources are limited and several factors affect conservation success.

  11. Hybridization of Southern Hemisphere blue whale subspecies and a sympatric area off Antarctica: impacts of whaling or climate change?

    Science.gov (United States)

    Attard, Catherine R M; Beheregaray, Luciano B; Jenner, K Curt S; Gill, Peter C; Jenner, Micheline-Nicole; Morrice, Margaret G; Robertson, Kelly M; Möller, Luciana M

    2012-12-01

    Understanding the degree of genetic exchange between subspecies and populations is vital for the appropriate management of endangered species. Blue whales (Balaenoptera musculus) have two recognized Southern Hemisphere subspecies that show differences in geographic distribution, morphology, vocalizations and genetics. During the austral summer feeding season, the Antarctic blue whale (B. m. intermedia) is found in polar waters and the pygmy blue whale (B. m. brevicauda) in temperate waters. Here, we genetically analyzed samples collected during the feeding season to report on several cases of hybridization between the two recognized blue whale Southern Hemisphere subspecies in a previously unconfirmed sympatric area off Antarctica. This means the pygmy blue whales using waters off Antarctica may migrate and then breed during the austral winter with the Antarctic subspecies. Alternatively, the subspecies may interbreed off Antarctica outside the expected austral winter breeding season. The genetically estimated recent migration rates from the pygmy to Antarctic subspecies were greater than estimates of evolutionary migration rates and previous estimates based on morphology of whaling catches. This discrepancy may be due to differences in the methods or an increase in the proportion of pygmy blue whales off Antarctica within the last four decades. Potential causes for the latter are whaling, anthropogenic climate change or a combination of these and may have led to hybridization between the subspecies. Our findings challenge the current knowledge about the breeding behaviour of the world's largest animal and provide key information that can be incorporated into management and conservation practices for this endangered species. © 2012 Blackwell Publishing Ltd.

  12. Annual Hematocrit Profiles in Two Subspecies of White-Crowned Sparrow: A Migrant and a Resident Comparison.

    Science.gov (United States)

    Krause, Jesse S; Németh, Zoltán; Pérez, Jonathan H; Chmura, Helen E; Ramenofsky, Marilyn; Wingfield, John C

    2016-01-01

    Hematocrit is an easily measured parameter that can be used to assess changes in oxygen carrying capacity necessitated by fluctuations in metabolic demands. Most hematocrit studies draw conclusions from changes in hematocrit that occur over a small sampling interval without an understanding of the variation that exists across the annual cycle. White-crowned sparrows provide an excellent model system due to the existence of a resident subspecies (Zonotrichia leucophrys nuttalli) that serves as a natural control for a migrant subspecies (Zonotrichia leucophrys gambelii). Comparing these two subspecies allows for the investigation of adaptive physiological changes at each life-history stage (i.e., migration, breeding, molt, etc.) in response to changing metabolic demands. Of particular interest, this subspecies comparison, by both calendar month and life-history stage, allows for the separation of adaptive increases in hematocrit due to migration from the natural seasonal variation in hematocrit. Hematocrit levels for males and females ranged throughout the year between 42%-47% and 40%-47% in the resident and between 45%-58% and 45%-56% in the migrant. In both subspecies, hematocrit levels were elevated during the breeding season compared to the nonbreeding season, and levels were reduced in females during egg laying. When grouped by life-history stage, hematocrit levels were always higher in the migrant compared to the resident. During the months in which migration occurred, hematocrit levels were 10%-12% higher in the migrant compared to the resident subspecies. These data suggest differential regulation of hematocrit between the two subspecies that may be attributed to phenotypic plasticity or genetic differences.

  13. Gene flow, subspecies composition, and dengue virus-2 susceptibility among Aedes aegypti collections in Senegal.

    Directory of Open Access Journals (Sweden)

    Massamba Sylla

    Full Text Available Aedes aegypti, the "yellow fever mosquito", is the primary vector to humans of the four serotypes of dengue viruses (DENV1-4 and yellow fever virus (YFV and is a known vector of Chikungunya virus. There are two recognized subspecies of Ae. aegypti sensu latu (s.l.: the presumed ancestral form, Ae. aegypti formosus (Aaf, a primarily sylvan mosquito in sub-Saharan Africa, and Ae. aegypti aegypti (Aaa, found globally in tropical and subtropical regions typically in association with humans. The designation of Ae. aegypti s.l. subspecies arose from observations made in East Africa in the late 1950s that the frequency of pale "forms" of Ae. aegypti was higher in populations in and around human dwellings than in those of the nearby bush. But few studies have been made of Ae. aegypti s.l. in West Africa. To address this deficiency we have been studying the population genetics, subspecies composition and vector competence for DENV-2 of Ae. aegypti s.l. in Senegal.A population genetic analysis of gene flow was conducted among 1,040 Aedes aegypti s.l. from 19 collections distributed across the five phytogeographic regions of Senegal. Adults lacking pale scales on their first abdominal tergite were classified as Aedes aegypti formosus (Aaf following the original description of the subspecies and the remainder were classified as Aedes aegypti aegypti (Aaa. There was a clear northwest-southeast cline in the abundance of Aaa and Aaf. Collections from the northern Sahelian region contained only Aaa while southern Forest gallery collections contained only Aaf. The two subspecies occurred in sympatry in four collections north of the Gambia in the central Savannah region and Aaa was a minor component of two collections from the Forest gallery area. Mosquitoes from 11 collections were orally challenged with DENV-2 virus. In agreement with the early literature, Aaf had significantly lower vector competence than Aaa. Among pure Aaa collections, the disseminated

  14. Morphometric and molecular differentiation between quetzal subspecies of Pharomachrus mocinno (Trogoniformes: Trogonidae

    Directory of Open Access Journals (Sweden)

    Sofía Solórzano

    2010-03-01

    Full Text Available The resplendent Quetzal (Pharomachrus mocinno is an endemic Mesoamerican bird species of conservation concern. Within this species, the subspecies P. m. costaricensis and P. m. mocinno, have been recognized by apparent morphometric differences; however, presently there is no sufficient data for confirmation. We analyzed eight morphometric attributes of the body from 41 quetzals: body length, tarsus and cord wing, as well as the length, wide and depth of the bill, body weight; and in the case of the males, the length of the long upper-tail cover feathers. We used multivariate analyses to discriminate morphometric differences between subspecies and contrasted each morphometric attribute between and within subspecies with paired non-parametric Wilcoxon test. In order to review the intraspecific taxonomic status of this bird, we added phylogenetic analysis, and genetic divergence and differentiation based on nucleotide variations in four sequences of mtDNA. The nucleotide variation was estimated in control region, subunit NDH6, and tRNA Glu and tRNA Phe in 26 quetzals from eight localities distributed in five countries. We estimated the genetic divergence and differentiation between subspecies according to a mutation-drift equilibrium model. We obtained the best mutation nucleotide model following the procedure implemented in model test program. We constructed the phylogenetic relationships between subspecies by maximum parsimony and maximum likelihood using PAUP, as well as with Bayesian statistics. The multivariate analyses showed two different morphometric groups, and individuals clustered according to the subspecies that they belong. The paired comparisons between subspecies showed strong differences in most of the attributes analyzed. Along the four mtDNA sequences, we identified 32 nucleotide positions that have a particular nucleotide according to the quetzals subspecies. The genetic divergence and the differentiation was strong and markedly

  15. A molecular marker distinguishes the subspecies Melipona quadrifasciata quadrifasciata and Melipona quadrifasciata anthidioides (Hymenoptera: Apidae, Meliponinae

    Directory of Open Access Journals (Sweden)

    Ana M. Waldschmidt

    2000-09-01

    Full Text Available The stingless bee species Melipona quadrifasciata includes two subspecies, Melipona quadrifasciata anthidioids and Melipona quadrifasciata quadrifasciata. The morphological difference between the two subspecies is the presence of three to five continuous yellow stripes on the terga on the 3rd to 6th segments in workers and males of M. q. quadrifasciata, and two to five interrupted bands in M. q. anthidioides. We identified a DNA marker which is present in M. q. quadrifasciata and absent in M. q. anthidioides. Only one among the M. q. quadrifasciata colonies did not present the marker. It was also absent in bees collected in northern Minas Gerais State (Brazil, despite their morphological resemblance to M. q. quadrifasciata. The marker can be used for studying the genetic structure of the hybridization zone formed by the intercrossing of the two subspecies.A espécie de abelha sem ferrão Melipona quadrifasciata apresenta duas subespécies, Melipona quadrifasciata quadrifasciata Lep. e Melipona quadrifasciata anthidioides Lep. A diferença morfológica entre as duas subespécies é a presença de três a cinco bandas tergais amarelas do 3º ao 6º segmentos em operárias e machos de M. q. quadrifasciata e duas a cinco bandas interrompidas em M. q. anthidioides. Nós identificamos um marcador de DNA que está presente em M. q. quadrifasciata e ausente em M. q. anthidioides. Este marcador está ausente em abelhas coletadas no norte do Estado de Minas Gerais (Brasil, embora esses indivíduos apresentem morfologia similar à de M. q. quadrifasciata. Este marcador poderá ser utilizado em estudos da zona de hibridação entre as subespécies.

  16. Morpho- biochemical evaluation of Brassica rapa sub-species for salt tolerance

    Directory of Open Access Journals (Sweden)

    Jan Sohail Ahmad

    2016-01-01

    Full Text Available Salt stress is one of the key abiotic stresses that affect both the qualitative and quantitative characters of many Brassica rapa sub-species by disturbing its normal morphobiochemical processes. Therefore, the present research work was designed to study the effect of different NaCl events (0, 50,100 and 150 mmol on morphological and biochemical characters and to screen salt tolerant genotypes among brown, yellow and toria types of B. rapa sub-species. The plants were grown in test tubes with addition of four level of NaCl (0, 50,100 and 150 mmol. The effect of salinity on shoot and root length, shoot/ root fresh and dry weight, relative water content (RWC, proline and chlorophyll a, b, a+b contents was recorded after 4 weeks of sowing. The genotype 22861 (brown type showed excellent morphological and biochemical performance at all stress levels followed by Toria-Sathi and Toria-A respectively as compared to Check variety TS-1. The genotype 26158 (yellow type gave very poor performance and retard growth. The %RWC values and chlorophyll a, b and a+b contents were decreased several folds with the increase of salt concentration. While, the proline contents was increased with raising of salt stress. The brown and toria types showed maximum tolerance to salt stress at early germination stages as compare to yellows one. The present study will serve as model to develop quick salt tolerant genotypes among different plant sub-species against salt stress.

  17. Associations of anthropometry and lifestyle factors with HDL subspecies according to apolipoprotein C-III.

    Science.gov (United States)

    Koch, Manja; Furtado, Jeremy D; Jiang, Gordon Z; Gray, Brianna E; Cai, Tianxi; Sacks, Frank; Tjønneland, Anne; Overvad, Kim; Jensen, Majken K

    2017-06-01

    The presence of apoC-III on HDL impairs HDL's inverse association with coronary heart disease (CHD). Little is known about modifiable factors explaining variation in HDL subspecies defined according to apoC-III. The aim was to investigate cross-sectional associations of anthropometry and lifestyle with HDL subspecies in 3,631 participants from the Diet, Cancer, and Health study originally selected for a case-cohort study (36% women; age 50-65 years) who were all free of CHD. Greater adiposity and less activity were associated with higher HDL containing apoC-III and lower HDL lacking apoC-III. Per each 15 cm higher waist circumference, the level of HDL containing apoC-III was 2.8% higher (95% CI: 0.4, 5.3; P = 0.024) and the level of HDL not containing apoC-III was 4.7% lower (95% CI: -6.0, -3.4; P = <0.0001). Associations for physical activity were most robust to multivariable modeling. Each 20 metabolic equivalent task hours per week reported higher physical activity was associated with 0.9% (95% CI: -1.7, -0.1; P = 0.031) lower HDL containing apoC-III and 0.5% higher (95% CI: 0.1, 1.0; P = 0.029) HDL lacking apoC-III. Lower alcohol consumption was associated with lower HDL lacking apoC-III (percent difference per 15 g/day: 1.58 (95% CI: 0.84, 2.32; P = <0.0001). Adiposity and sedentary lifestyle were associated with a less favorable HDL subspecies profile. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

  18. New insights about phenotypic heterogeneity withinPropionibacterium freudenreichiiargue against its division into subspecies.

    Science.gov (United States)

    de Freitas, Rosangela; Madec, Marie-Noelle; Chuat, Victoria; Maillard, Marie-Bernadette; Mukdsi, María C Abeijón; Falentin, Hélène; de Carvalho, Antonio Fernandes; Valence, Florence; Thierry, Anne

    Propionibacterium freudenreichii is widely used in Swiss-type cheese manufacture, where it contributes to flavour and eye development. It is currently divided into two subspecies, according to the phenotype for lactose fermentation and nitrate reduction (lac + /nit - and lac - /nit + for P. freudenreichii subsp. shermanii and subsp. freudenreichii , respectively). However, the existence of unclassifiable strains (lac + /nit + and lac - /nit - ) has also been reported. The aim of this study was to revisit the relevance of the subdivision of P. freudenreichii into subspecies, by confirming the existence of unclassifiable strains. Relevant conditions to test the ability of P. freudenreichii for lactose fermentation and nitrate reduction were first determined, by using 10 sequenced strains, in which the presence or absence of the lactose and nitrate genomic islands were known. We also determined whether the subdivision based on lac/nit phenotype was related to other phenotypic properties of interest in cheese manufacture, in this case, the production of aroma compounds, analysed by gas chromatography-mass spectrometry, for a total of 28 strains. The results showed that a too short incubation time can lead to false negative for lactose fermentation and nitrate reduction. They confirmed the existence of four lac/nit phenotypes instead of the two expected, thus leading to 13 unclassifiable strains out of the 28 characterized (7 lac + /nit + and 6 lac - /nit - ). The production of the 15 aroma compounds detected in all cultures varied more within a lac/nit phenotype (up to 20 times) than between them. Taken together, these results demonstrate that the division of P. freudenreichii into two subspecies does not appear to be relevant.

  19. First record of the genus Pycnodictya with its subspecies P. galinieri galinieri from Egypt (Orthoptera, Acrididae

    Directory of Open Access Journals (Sweden)

    Asmaa A. Haggag

    2016-11-01

    Full Text Available The band-winged Pycnodictya galinieri galinieri (Reiche & Fairmaire, 1849 and its genus Pycnodictya Stål, 1873 (Orthoptera: Acrididae: Oedipodinae are recorded for the first time for the Egyptian fauna. The species was collected from Gabal Elba, in the southeastern corner of Egypt. This record expands the known distributional range of P. galinieri towards the north of Africa. Descriptions of the genus and the Egyptian subspecies are given using multiple diagnostic characters. The descriptions are supplemented by drawings and photographs of the specimen collected. It is proposed that the genus Pycnodictya belongs to the tribe Locustini.

  20. First record of the genus Pycnodictya with its subspecies P. galinieri galinieri from Egypt (Orthoptera, Acrididae)

    Science.gov (United States)

    Haggag, Asmaa A.

    2016-01-01

    Abstract The band-winged Pycnodictya galinieri galinieri (Reiche & Fairmaire, 1849) and its genus Pycnodictya Stål, 1873 (Orthoptera: Acrididae: Oedipodinae) are recorded for the first time for the Egyptian fauna. The species was collected from Gabal Elba, in the southeastern corner of Egypt. This record expands the known distributional range of Pycnodictya galinieri towards the north of Africa. Descriptions of the genus and the Egyptian subspecies are given using multiple diagnostic characters. The descriptions are supplemented by drawings and photographs of the specimen collected. It is proposed that the genus Pycnodictya belongs to the tribe Locustini. PMID:27917042

  1. Purulent Pericarditis with Salmonella enterica Subspecies arizona in a Patient with Type 2 Diabetes Mellitus.

    Science.gov (United States)

    Suzuki, Ai; Tanaka, Takamitsu; Ohba, Kenji; Ito, Naomi; Sakai, Yuki; Kaneko, Akane; Machii, Masashi; Nonaka, Daishi; Goto, Yoshie; Takase, Hiroyuki

    2017-08-15

    Purulent pericarditis is a life-threatening disorder, even in the modern antibiotic era. Although diabetes mellitus is known to be associated with an increased risk of multiple types of infections, purulent pericarditis is extremely rare. We herein report an unusual case of pericarditis caused by Salmonella enterica subspecies arizona that was not associated with any evident underlying immunosuppressive disorder apart from uncontrolled type 2 diabetes mellitus. Because a pet snake was suspected as being the source of infection in the present case, patient education and a detailed review of exposure history could play an important role in treating patients with diabetes mellitus.

  2. Genetic relationships among some subspecies of the Peregrine Falcon (Falco peregrinus L.), inferred from mitochondrial DNA control-region sequences

    Science.gov (United States)

    White, Clayton M.; Sonsthagen, Sarah A.; Sage, George K.; Anderson, Clifford; Talbot, Sandra L.

    2013-01-01

    The ability to successfully colonize and persist in diverse environments likely requires broad morphological and behavioral plasticity and adaptability, and this may partly explain why the Peregrine Falcon (Falco peregrinus) exhibits a large range of morphological characteristics across their global distribution. Regional and local differences within Peregrine Falcons were sufficiently variable that ∼75 subspecies have been described; many were subsumed, and currently 19 are generally recognized. We used sequence information from the control region of the mitochondrial genome to test for concordance between genetic structure and representatives of 12 current subspecies and from two areas where subspecies distributions overlap. Haplotypes were broadly shared among subspecies, and all geographic locales shared a widely distributed common haplotype (FalconCR2). Haplotypes were distributed in a star-like phylogeny, consistent with rapid expansion of a recently derived species, with observed genetic patterns congruent with incomplete lineage sorting and/or differential rates of evolution on morphology and neutral genetic characters. Hierarchical analyses of molecular variance did not uncover genetic partitioning at the continental level, despite strong population-level structure (FST = 0.228). Similar analyses found weak partitioning, albeit significant, among subspecies (FCT = 0.138). All reconstructions placed the hierofalcons' (Gyrfalcon [F. rusticolus] and Saker Falcon [F. cherrug]) haplotypes in a well-supported clade either basal or unresolved with respect to the Peregrine Falcon. In addition, haplotypes representing Taita Falcon (F. fasciinucha) were placed within the Peregrine Falcon clade.

  3. Streptococcal toxic-shock syndrome due to Streptococcus dysgalactiae subspecies equisimilis in breast cancer-related lymphedema: a case report.

    Science.gov (United States)

    Sumazaki, Makoto; Saito, Fumi; Ogata, Hideaki; Yoshida, Miho; Kubota, Yorichika; Magoshi, Syunsuke; Kaneko, Hironori

    2017-07-14

    Breast cancer-related lymphedema often causes cellulitis and is one of the most common complications after breast cancer surgery. Streptococci are the major pathogens underlying such cellulitis. Among the streptococci, the importance of the Lancefield groups C and G is underappreciated; most cases involve Streptococcus dysgalactiae subspecies equisimilis. Despite having a relatively weak toxicity compared with group A streptococci, Streptococcus dysgalactiae subspecies equisimilis is associated with a mortality rate that is as high as that of group A streptococci in cases of invasive infection because Streptococcus dysgalactiae subspecies equisimilis mainly affects elderly individuals who already have various comorbidities. An 83-year-old Japanese woman with breast cancer-related lymphedema in her left upper limb was referred to our hospital with high fever and acute pain with erythema in her left arm. She showed septic shock with disseminated intravascular coagulation. Blood culture showed positive results for Streptococcus dysgalactiae subspecies equisimilis, confirming a diagnosis of streptococcal toxic-shock syndrome. She survived after successful intensive care. To the best of our knowledge, this case represents the first report of Streptococcus dysgalactiae subspecies equisimilis-induced streptococcal toxic-shock syndrome in a patient with breast cancer-related lymphedema. Breast cancer-related lymphedema is a common problem, and we must pay attention to invasive streptococcal soft tissue infections, particularly in elderly patients with chronic disease.

  4. 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.

  5. 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

  6. 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)

  7. Environmental Assessment Aerial Application of Pesticide for Mosquito Control at Tyndall Air Force Base and Vicinity

    Science.gov (United States)

    2008-10-27

    the toxicity of Bacillus thuringiensis var. israelensis against organisms found in association with mosquito larvae . Proc. Ann. Conf. of the Calif...and bioratiooal control measures and encourage the use of personn el protective measures. C. Conduct aerial larval control using Bacillus ...personnel protective measures; 3) Conduct aerial larval control using Bacillus thuringiensis var. israelensis (B.t.i.) , limited to Tyndall AFB prope1ty

  8. Disruptive Technology for Vector Control: the Innovative Vector Control Consortium and the US Military Join Forces to Explore Transformative Insecticide Application Technology for Mosquito Control Programmes

    Science.gov (United States)

    2015-09-26

    Bacillus thuringiensis israelensis (Bti) are proving highly effective in container habitats. Lar- vicide application techniques that utilize hand held or...Williams GM, Faraji A, Unlu I, Healy SP, Farooq M, Gaugler R, et al. Area- wide ground applications of Bacillus thuringiensis var. israelensis for the...fever: an environmental plague for the new millennium? 1999. http://www.ehproject.org/ PDF /Capsule/cap- sule2_dengue.pdf. Accessed 5 Feb 2015. 4. WHO

  9. 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.

  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. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

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

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    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.

  1. Application of a multiplex PCR assay for Campylobacter fetus detection and subspecies differentiation in uncultured samples of aborted bovine fetuses.

    Science.gov (United States)

    Iraola, Gregorio; Hernández, Martín; Calleros, Lucía; Paolicchi, Fernando; Silveyra, Silvia; Velilla, Alejandra; Carretto, Luis; Rodríguez, Eliana; Pérez, Ruben

    2012-12-01

    Campylobacter (C.) fetus (epsilonproteobacteria) is an important veterinary pathogen. This species is currently divided into C. fetus subspecies (subsp.) fetus (Cff) and C. fetus subsp. venerealis (Cfv). Cfv is the causative agent of bovine genital Campylobacteriosis, an infectious disease that leads to severe reproductive problems in cattle worldwide. Cff is a more general pathogen that causes reproductive problems mainly in sheep although cattle can also be affected. Here we describe a multiplex PCR method to detect C. fetus and differentiate between subspecies in a single step. The assay was standardized using cultured strains and successfully used to analyze the abomasal liquid of aborted bovine fetuses without any pre-enrichment step. Results of our assay were completely consistent with those of traditional bacteriological diagnostic methods. Furthermore, the multiplex PCR technique we developed may be easily adopted by any molecular diagnostic laboratory as a complementary tool for detecting C. fetus subspecies and obtaining epidemiological information about abortion events in cattle.

  2. Differentiation of Cannabis subspecies by THCA synthase gene analysis using RFLP.

    Science.gov (United States)

    Cirovic, Natasa; Kecmanovic, Miljana; Keckarevic, Dusan; Keckarevic Markovic, Milica

    2017-10-01

    Cannabis sativa subspecies, known as industrial hemp (C. sativa sativa) and marijuana (C. sativa indica) show no evident morphological distinctions, but they contain different levels of psychoactive Δ-9-tetrahidrocanabinol (THC), with considerably higher concentration in marijuana than in hemp. C. sativa subspecies differ in sequence of tetrahydrocannabinolic acid (THCA) synthase gene, responsible for THC production, and only one active copy of the gene, distinctive for marijuana, is capable of producing THC in concentration more then 0,3% in dried plants, usually punishable by the law. Twenty different samples of marijuana that contain THC in concentration more then 0,3% and three varieties of industrial hemp were analyzed for presence of an active copy of THCA synthase gene using in-house developed restriction fragment length polymorphism (RFLP) method All twenty samples of marijuana were positive for the active copy of THCA synthase gene, 16 of them heterozygous. All three varieties of industrial hemp were homozygous for inactive copy. An algorithm for the fast and accurate forensic analysis of samples suspected to be marijuana was constructed, answering the question if an analyzed sample is capable of producing THC in concentrations higher than 0.3%. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  3. Electrocardiography in two subspecies of manatee (Trichechus manatus latirostris and Trichechus manatus manatus)

    Science.gov (United States)

    Siegal-Willott, J.; Estrada, A.; Bonde, R.K.; Wong, A.; Estrada, D.J.; Harr, K.

    2006-01-01

    Electrocardiographic (ECG) measurements were recorded in two subspecies of awake, apparently healthy, wild manatees (Trichechus manatus latirostris and T. m. manatus) undergoing routine field examinations in Florida and Belize. Six unsedated juveniles (dependent and independent calves) and 6 adults were restrained in ventral recumbency for ECG measurements. Six lead ECGs were recorded for all manatees and the following parameters were determined: heart rate and rhythm; P, QRS, and T wave morphology, amplitude, and duration; and mean electrical axis (MEA). Statistical differences using a t-test for equality of means were determined. No statistical difference was seen based on sex or subspecies of manatees in the above measured criteria. Statistical differences existed in heart rate (P = 0.047), P wave duration (P = 0.019), PR interval (P = 0.025), and MEA (P = 0.021) between adult manatees and calves. Our findings revealed normal sinus rhythms, no detectable arrhythmias, prolonged PR and QT intervals, prolonged P wave duration, and small R wave amplitude as compared with cetacea and other marine mammals. This paper documents the techniques for and baseline recordings of ECGs in juvenile and adult free-living manatees. It also demonstrates that continual assessment of cardiac electrical activity in the awake manatee can be completed and can be used to aid veterinarians and biologists in routine health assessment, during procedures, and in detecting the presence of cardiac disease or dysfunction.

  4. Karyotypic evolution of ribosomal sites in buffalo subspecies and their crossbreed

    Directory of Open Access Journals (Sweden)

    Tiago Marafiga Degrandi

    2014-06-01

    Full Text Available Domestic buffaloes are divided into two group based on cytogenetic characteristics and habitats: the "river buffaloes" with 2n = 50 and the "swamp buffaloes", 2n = 48. Nevertheless, their hybrids are viable, fertile and identified by a 2n = 49. In order to have a better characterization of these different cytotypes of buffaloes, and considering that NOR-bearing chromosomes are involved in the rearrangements responsible for the karyotypic differences, we applied silver staining (Ag-NOR and performed fluorescent in situ hybridization (FISH experiments using 18S rDNA as probe. Metaphases were obtained through blood lymphocyte culture of 21 individuals, including river, swamp and hybrid cytotypes. Ag-NOR staining revealed active NORs on six chromosome pairs (3p, 4p, 6, 21, 23, 24 in the river buffaloes, whereas the swamp buffaloes presented only five NOR-bearing pairs (4p, 6, 20, 22, 23. The F1 crossbreed had 11 chromosomes with active NORs, indicating expression of both parental chromosomes. FISH analysis confirmed the numerical divergence identified with Ag-NOR. This result is explained by the loss of the NOR located on chromosome 4p in the river buffalo, which is involved in the tandem fusion with chromosome 9 in this subspecies. A comparison with the ancestral cattle karyotype suggests that the NOR found on the 3p of the river buffalo may have originated from a duplication of ribosomal genes, resulting in the formation of new NOR sites in this subspecies.

  5. 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.

  6. Molecular analysis of phylogeographic subspecies in three Ponto-Caspian sturgeon species

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    Andreea Dudu

    2014-09-01

    Full Text Available Sturgeons (Order Acipenseriformes represent an extremely valuable natural resource that is now facing depletion. In the current study we evaluate if the traditional classification in subspecies of Acipenser gueldenstaedtii, Acipenser stellatus and Huso huso, endemic to Ponto-Caspian region is sustained by molecular analysis and if these represent Evolutionary Significant Units (ESUs that should be managed separately in conservation programs. To examine the classification of taxonomic entities we sequenced a fragment of the mitochondrial control region in case of three sturgeon species that inhabit the North-western of Black Sea and migrate for reproduction in the Lower Danube. Beside these sequences, we used previously published sequences from sturgeon individuals sampled in the Black Sea, Azov Sea and Caspian Sea. We determined the genetic diversity and genetic differentiation, conducted a Population Aggregation Analysis (PAA and inferred an intraspecific molecular phylogeny and haplotype network. The results indicated a low level of genetic differentiation between the geographically designated subspecies and did not support a significant divergence or reciprocal monophyly between them. Our results confirm previous genetic studies with smaller samples sizes, but additional analyses including nuclear markers should be conducted for proper recommendations aiming at the development of conservation programs.

  7. Detection of Mycobacterium avium subspecies in the gut associated lymphoid tissue of slaughtered rabbits.

    Science.gov (United States)

    Arrazuria, Rakel; Sevilla, Iker A; Molina, Elena; Pérez, Valentín; Garrido, Joseba M; Juste, Ramón A; Elguezabal, Natalia

    2015-06-11

    Rabbits are susceptible to infection by different species of the genus Mycobacterium. Particularly, development of specific lesions and isolation of Mycobacterium avium subsp. avium and Mycobacterium avium subsp. paratuberculosis, both subspecies of the M. avium complex, has been reported in wildlife conditions. Although, rabbit meat production worldwide is 200 million tons per year, microbiological data on this source of meat is lacking and more specifically reports of mycobacterial presence in industrially reared rabbit for human consumption have not been published. To this end, we sought mycobacteria by microbiological and histopathological methods paying special attention to Mycobacterium avium subsp. paratuberculosis in rabbits from commercial rabbitries from the North East of Spain. M. avium subsp. paratuberculosis was not detected either by culture or PCR. However, Mycobacterium avium subsp. avium was detected in 15.15% (10/66) and Mycobacterium avium subsp. hominissuis was detected in 1.51% (1/66) of gut associated lymphoid tissue of sampled animals by PCR, whereas caecal contents were negative. 9% (6/66) of the animals presented gross lesions suggestive of lymphoid activation, 6% (4/66) presented granulomatous lesions and 3% (2/66) contained acid fast bacilli. Mycobacterial isolation from samples was not achieved, although colonies of Thermoactinomycetes sp. were identified by 16s rRNA sequencing in 6% (4/66) of sampled animals. Apparently healthy farmed rabbits that go to slaughter may carry M. avium subspecies in gut associated lymphoid tissue.

  8. Phylogeography of Koramius charltonius (Gray, 1853 (Lepidoptera: Papilionidae: a case of too many poorly circumscribed subspecies

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    Stanislav K. Korb

    2016-10-01

    Full Text Available Koramius charltonius (Gray, 1853 (Lepidoptera: Papilionidae is distributed in the mountains of Central Asia. We analysed genetic and phylogeographic patterns throughout the western part of its range using a mitochondrial marker (COI. We also analysed the wing pattern using multivariate statistics. We found that the species contains several unique haplotypes in the west and shared haplotypes in the east. The haplotype groups do not correspond to the wing pattern and also the described subspecies do not correspond to either the haplotypes or the groups circumscribed by the wing pattern. Currently, there are more than ten subspecies of K. charltonius in Central Asia; based on our analyses we suggest a reduction to only five of them. The following nomenclatural changes are applied: (1 K. charltonius aenigma Dubatolov & Milko, 2003, syn. n., K. charltonius sochivkoi Churkin, 2009, syn.n., and K. charltonius alrashid Churkin & Pletnev, 2012, syn. n. are new synonyms of K. charltonius romanovi (Grum-Grshimailo, 1885; (2 K. charltonius marusya Churkin & Pletnev, 2012, syn. n., K. charltonius eugenia Churkin, 2009, syn. n., K. charltonius anjuta Stshetkin & Kaabak, 1985, syn. n., and K. charltonius mistericus Kaabak, Sotchivko & Titov, 1996, syn. n. are new synonyms of K. charltonius vaporosus (Avinov, 1913; and (3 K. charltonius safronovi Korb, Shaposhnikov, Zatakovoy & Nikolaev, 2013, syn. n. is a new synonym of K. charltonius voigti (Bang-Haas, 1927.

  9. Investigation of the Fim1 putative pilus locus of Streptococcus equi subspecies equi.

    Science.gov (United States)

    Steward, Karen Frances; Robinson, Carl; Maskell, Duncan J; Nenci, Chiara; Waller, Andrew Stephen

    2017-07-28

    The Gram-positive bacterium Streptococcus equi subspecies equi (S. equi) is the causative agent of strangles, among the most frequently diagnosed infectious diseases of horses worldwide. Genome analysis of S. equi strain 4047 (Se4047) identified a putative operon, Fim1, with similarity to the pilus loci of other Gram-positive bacteria. The Fim1 locus was present in all strains of S. equi and its close relative S. equi subspecies zooepidemicus (S. zooepidemicus) that have been studied to date. In this study we provide evidence that the putative structural pilus proteins, SEQ_0936 and CNE, are produced on the cell surface during in vitro growth and in vivo infection. Although the proteins encoded within the Fim1 locus are not essential for attachment or biofilm formation, over-transcription of SEQ_0936 and CNE enhanced attachment to equine tissue in vitro. Our data suggest that whilst the Fim1 locus does not produce a polymerized pilus structure, the products of the Fim1 locus may fulfil an adhesive function. The putative pilus-associated regulator, tetR, which contains a nonsense mutation in S. equi, was able to regulate transcription of the Fim1 locus following repair and over-transcription, confirming its predicted role in the operon.

  10. Mitochondrial-DNA variation among subspecies and populations of sea otters (Enhydra lutris)

    Science.gov (United States)

    Cronin, Matthew A.; Bodkin, James L.; Ballachey, Brenda E.; Estes, James A.; Patton, John C.

    1996-01-01

    We used restriction-enzyme analysis of polymerase-chain reaction-amplified, mitochondrial DNA (mtDNA) to assess genetic differentiation of subspecies and populations of sea otters, Enhydra lutris, throughout the range of the species. There were several haplotypes of mtDNA in each subspecies and geographically separate populations. MtDNA sequence divergence of haplotypes of sea otters was 0.0004–0.0041 base substitutions per nucleotide. E. L nereis appears to have monophyletic mitochondrial DNA, while E. I. lutris and E. I. kenyoni do not. Different frequencies of haplotypes of mtDNA among populations reflect current restriction of gene flow and the unique histories of different populations. There are two or three haplotypes of mtDNA and diversity of haplotypes is 0.1376–0.5854 in each population of otters. This is consistent with theoretical work, which suggests that population bottlenecks of sea otters probably did not result in major losses of genetic variation for individual populations, or the species as a whole.

  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. Spatial Variation and Survival of Salmonella enterica Subspecies in a Population of Australian Sleepy Lizards (Tiliqua rugosa)

    Science.gov (United States)

    Parsons, Sandra K.; Bull, C. Michael

    2015-01-01

    The life cycles of many enteric bacterial species require a transition between two very distinct environments. Their primary habitat is the gastrointestinal tract of the host, while their secondary habitat, during transmission from one host to another, consists of environments external to the host, such as soil, water, and sediments. Consequently, both host and environmental factors shape the genetic structure of enteric bacterial populations. This study examined the distribution of four Salmonella enterica subspecies in a population of sleepy lizards, Tiliqua rugosa, in a semiarid region of South Australia. The lizards living within the 1,920-m by 720-m study site were radio tracked, and their enteric bacteria were sampled at regular intervals throughout their active seasons in the years 2001, 2002, and 2006. Four of the six subspecies of S. enterica were present in this population and were nonrandomly distributed among the lizards. In particular, S. enterica subsp. diarizonae was restricted to lizards living in the most shaded parts of the study site with an overstorey of Casuarina trees. Experiments undertaken to investigate the survival of S. enterica cells under seminatural conditions revealed that cell survival decreased with increased exposure to elevated temperatures and UV light. Among the three S. enterica subspecies tested, S. enterica subsp. diarizonae consistently had an average expected life span that was shorter than that observed for the other two subspecies. There was no indication in the data that there was any competitive dominance hierarchy among the S. enterica subspecies within individual hosts. Thus, the nonrandom distribution of S. enterica subspecies in this population of lizards appears to be driven by their different survival characteristics in the external environment. PMID:26092451

  13. Single nucleotide polymorphism discovery in cutthroat trout subspecies using genome reduction, barcoding, and 454 pyro-sequencing

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    Houston Derek D

    2012-12-01

    Full Text Available Abstract Background Salmonids are popular sport fishes, and as such have been subjected to widespread stocking throughout western North America. Historically, stocking was done with little regard for genetic variation among populations and has resulted in genetic mixing among species and subspecies in many areas, thus putting the genetic integrity of native salmonid populations at risk and creating a need to assess the genetic constitution of native salmonid populations. Cutthroat trout is a salmonid species with pronounced geographic structure (there are 10 extant subspecies and a recent history of hybridization with introduced rainbow trout in many populations. Genetic admixture has also occurred among cutthroat trout subspecies in areas where introductions have brought two or more subspecies into contact. Consequently, management agencies have increased their efforts to evaluate the genetic composition of cutthroat trout populations to identify populations that remain uncompromised and manage them accordingly, but additional genetic markers are needed to do so effectively. Here we used genome reduction, MID-barcoding, and 454-pyrosequencing to discover single nucleotide polymorphisms that differentiate cutthroat trout subspecies and can be used as a rapid, cost-effective method to characterize the genetic composition of cutthroat trout populations. Results Thirty cutthroat and six rainbow trout individuals were subjected to genome reduction and next-generation sequencing. A total of 1,499,670 reads averaging 379 base pairs in length were generated by 454-pyrosequencing, resulting in 569,060,077 total base pairs sequenced. A total of 43,558 putative SNPs were identified, and of those, 125 SNP primers were developed that successfully amplified 96 cutthroat trout and rainbow trout individuals. These SNP loci were able to differentiate most cutthroat trout subspecies using distance methods and Structure analyses. Conclusions Genomic and

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  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

    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.

  1. Isolation of Bartonella henselae and Two New Bartonella Subspecies, Bartonella koehlerae Subspecies boulouisii subsp. nov. and Bartonella koehlerae Subspecies bothieri subsp. nov. from Free-Ranging Californian Mountain Lions and Bobcats

    Science.gov (United States)

    Chomel, Bruno B.; Molia, Sophie; Kasten, Rickie W.; Borgo, Gina M.; Stuckey, Matthew J.; Maruyama, Soichi; Chang, Chao-chin; Haddad, Nadia; Koehler, Jane E.

    2016-01-01

    Domestic cats are the natural reservoir of Bartonella henselae, B. clarridgeiae and B. koehlerae. To determine the role of wild felids in the epidemiology of Bartonella infections, blood was collected from 14 free-ranging California mountain lions (Puma concolor) and 19 bobcats (Lynx rufus). Bartonella spp. were isolated from four (29%) mountain lions and seven (37%) bobcats. These isolates were characterized using growth characteristics, biochemical reactions, molecular techniques, including PCR-RFLP of selected genes or interspacer region, pulsed-field gel electrophoresis (PFGE), partial sequencing of several genes, and DNA-DNA hybridization. Two isolates were identical to B. henselae genotype II. All other isolates were distinguished from B. henselae and B. koehlerae by PCR-RFLP of the gltA gene using endonucleases HhaI, TaqI and AciI, with the latter two discriminating between the mountain lion and the bobcat isolates. These two novel isolates displayed specific PFGE profiles distinct from B. henselae, B. koehlerae and B. clarridgeiae. Sequences of amplified gene fragments from the three mountain lion and six bobcat isolates were closely related to, but distinct from, B. henselae and B. koehlerae. Finally, DNA-DNA hybridization studies demonstrated that the mountain lion and bobcat strains are most closely related to B. koehlerae. We propose naming the mountain lion isolates B. koehlerae subsp. boulouisii subsp. nov. (type strain: L-42-94), and the bobcat isolates B. koehlerae subsp. bothieri subsp. nov. (type strain: L-17-96), and to emend B. koehlerae as B. koehlerae subsp. koehlerae. The mode of transmission and the zoonotic potential of these new Bartonella subspecies remain to be determined. PMID:26981874

  2. Isolation of Bartonella henselae and Two New Bartonella Subspecies, Bartonellakoehlerae Subspecies boulouisii subsp. nov. and Bartonella koehlerae Subspecies bothieri subsp. nov. from Free-Ranging Californian Mountain Lions and Bobcats.

    Science.gov (United States)

    Chomel, Bruno B; Molia, Sophie; Kasten, Rickie W; Borgo, Gina M; Stuckey, Matthew J; Maruyama, Soichi; Chang, Chao-Chin; Haddad, Nadia; Koehler, Jane E

    2016-01-01

    Domestic cats are the natural reservoir of Bartonella henselae, B. clarridgeiae and B. koehlerae. To determine the role of wild felids in the epidemiology of Bartonella infections, blood was collected from 14 free-ranging California mountain lions (Puma concolor) and 19 bobcats (Lynx rufus). Bartonella spp. were isolated from four (29%) mountain lions and seven (37%) bobcats. These isolates were characterized using growth characteristics, biochemical reactions, molecular techniques, including PCR-RFLP of selected genes or interspacer region, pulsed-field gel electrophoresis (PFGE), partial sequencing of several genes, and DNA-DNA hybridization. Two isolates were identical to B. henselae genotype II. All other isolates were distinguished from B. henselae and B. koehlerae by PCR-RFLP of the gltA gene using endonucleases HhaI, TaqI and AciI, with the latter two discriminating between the mountain lion and the bobcat isolates. These two novel isolates displayed specific PFGE profiles distinct from B. henselae, B. koehlerae and B. clarridgeiae. Sequences of amplified gene fragments from the three mountain lion and six bobcat isolates were closely related to, but distinct from, B. henselae and B. koehlerae. Finally, DNA-DNA hybridization studies demonstrated that the mountain lion and bobcat strains are most closely related to B. koehlerae. We propose naming the mountain lion isolates B. koehlerae subsp. boulouisii subsp. nov. (type strain: L-42-94), and the bobcat isolates B. koehlerae subsp. bothieri subsp. nov. (type strain: L-17-96), and to emend B. koehlerae as B. koehlerae subsp. koehlerae. The mode of transmission and the zoonotic potential of these new Bartonella subspecies remain to be determined.

  3. 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.

  4. 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.

  5. Illustration of the Difficulty of Identifying Streptococcus equi Strains at the Subspecies Level through a Case of Endocarditis in an Immunocompetent Man

    Science.gov (United States)

    Daubié, Anne Sophie; Defrance, Carine; Renvoisé, Aurélie; Barreda, Eleodoro; D'Alessandro, Cosimo; Brossier, Florence; Jarlier, Vincent

    2014-01-01

    We report a case of endocarditis caused by Streptococcus equi in an immunocompetent patient who was subsequently cured after appropriate antibiotherapy and cardiac surgery. However, it was challenging to identify the strain to the subspecies level, which highlights the necessity of developing reliable molecular tools to discriminate between the subspecies. PMID:24478515

  6. Satellite tracking of the migratory pathways of the first-year Lesser Black-backed Gulls Larus fuscus departing from the breeding grounds of different subspecies

    DEFF Research Database (Denmark)

    Pütz, Klemens; Rahbek, Carsten; Saurola, Pertti

    2007-01-01

    of the other subspecies. In addition, first-year birds from cross-breeding experiments between the two subspecies (fuscus x intermedius) were also equipped with satellite transmitters. In total, eleven first-year birds were successfully tracked during their initial autumn migration, at least one from each...... study group. First-year birds from the Danish intermedius subspecies migrated either southwest along the coast of the North Sea or through central Europe to Algeria. By contrast, first-year birds from the Finnish fuscus subspecies migrated on a south-southeastern course towards Ukraine and the Bosporus......The migratory behaviour of two Lesser Black-backed Gull Larus fuscus subspecies, fuscus and intermedius, was studied using satellite telemetry. To this end, first-year birds were equipped with satellite transmitters and released either at their natal site, or after transferring to a breeding site...

  7. 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.

  8. 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.

  9. 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...

  10. Isolation of Bacillus thuringiensis from the state of Amazonas, in Brazil, and screening against Aedes aegypti (Diptera, Culicidae

    Directory of Open Access Journals (Sweden)

    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.

  11. 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

  12. Identical metabolic rate and thermal conductance in Rock Sandpiper (Calidris ptilocnemis) subspecies with contrasting nonbreeding life histories

    NARCIS (Netherlands)

    Ruthrauff, Dan; Dekinga, Anne; Gill, Robert E.; Piersma, Theunis

    Closely related species or subspecies can exhibit metabolic differences that reflect site-specific environmental conditions. Whether such differences represent fixed traits or flexible adjustments to local conditions, however, is difficult to predict across taxa. The nominate race of Rock Sandpiper

  13. DNA barcoding of gypsy moths from China (Lepidoptera: Erebidae) reveals new haplotypes and divergence patterns within gypsy moth subspecies

    Science.gov (United States)

    Fang Chen; Youqing Luo; Melody A. Keena; Ying Wu; Peng Wu; Juan Shi

    2015-01-01

    The gypsy moth from Asia (two subspecies) is considered a greater threat to North America than European gypsy moth, because of a broader host range and females being capable of flight. Variation within and among gypsy moths from China (nine locations), one of the native countries of Asian gypsy moth, were compared using DNA barcode sequences (658 bp of mtDNA cytochrome...

  14. Taxonomic reassessment of two subspecies of Chinese skink in Taiwan based on morphological and molecular investigations (Squamata, Scincidae).

    Science.gov (United States)

    Kurita, Kazuki; Nakamura, Yukiko; Okamoto, Taku; Lin, Si-Min; Hikida, Tsutomu

    2017-01-01

    The Chinese skink, Plestiodon chinensis (Gray, 1838), is widely distributed across continental China, Taiwan, the Korean Peninsula, and offshore islets, and consists of several subspecies. Here morphological and molecular methods have been used to reassess the taxonomic status and distributions of P. c. formosensis (Van Denburgh, 1912) and P. c. leucostictus (Hikida, 1988), which are endemic to Taiwan and Green Island (an islet off the east coast of Taiwan), respectively. It can be confirmed that the eastern Taiwanese populations of P. c. formosensis exhibit similar juvenile color patterning and genetic composition to the islet subspecies P. c. leucostictus , and are distinct from consubspecific populations in western Taiwan. Therefore, the eastern Taiwanese populations are assigned to P. c. leucostictus , and this subspecies is recognized as a distinct species, Plestiodon leucostictus (Hikida, 1988), based on their unique juvenile coloration and highly divergent DNA sequences. Our results also revealed that P. c. formosensis in western Taiwan is close to nominotypical subspecies from the continent, suggesting the necessity of a comprehensive taxonomic analysis in the future.

  15. Serotypes of Salmonella enterica subspecies I isolated from mice caught on US poultry farms 1995 through 1998

    Science.gov (United States)

    Whole genome analysis of foodborne pathogens is standard practice for regulatory agencies in the US, and a goal of 1 million genomes for Salmonella enterica is currently 76% complete. Inclusion of a range of Salmonella enterica subspecies I serotypes is important because only 30 of approximately 150...

  16. Genetic relationship among subspecies of Musa acuminata Colla and A-genome consisting edible cultivated bananas assayed with ISSR markers

    Directory of Open Access Journals (Sweden)

    Phruet Racharak

    2007-11-01

    Full Text Available Genetic relationship among subspecies of Musa acuminata and A-genome consisting edible cultivated bananas was investigated by ISSR (inter-simple sequence repeat markers. Twelve samples of wild type bananas that were classified into 5 subspecies of Musa acuminata, thirty-three samples of edible cultivatedbananas and M. balbisiana were used as plant materials for this study. Of a total of 36 ISSR primers screened, 6 primers revealed a total of 128 alleles, allele size varied from 200 to 3,000 bp with an average of 21.33 alleles per primer, average of allele frequency was 0.18, polymorphic percentage was 1.0 and heterozygositywas 0.29. From the dendrogram, banana samples can be divided into two main clusters with similarity coefficient value at 0.18. The first cluster belonged to the out group which included Musa itinerans and Ensete glaucum, the second cluster belonged to Musa coccinea, M. laterita, all subspecies of M. acuminata, M. balbisiana and all the cultivar groups of the edible cultivated bananas and plantains. In addition, the results indicated two Musa species, consisting of M. coccinea and M. laterita, were sister group of the second cluster as well. All specimens of subspecies of M. acuminata were related to cultivated groups of A-genome consisting of cultivated bananas in Thailand.

  17. A global assessment of the conservation status of the nominate subspecies of Eurasian oystercatcher (Haematopus ostralegus ostralegus)

    NARCIS (Netherlands)

    Van de Pol, M.; Atkinson, P.W.; Blew, J.; Duriez, O.P.M.; Ens, B.J.; Hälterlein, B.; Hötker, H.; Laursen, K.; Oosterbeek, K.H.; Petersen, A.; Thorup, O.; Tjørve, K.; Triplet, P.; Yésou, P.

    2014-01-01

    The nominate subspecies of Eurasian Oystercatchers Haematopus ostralegus ostralegus is the most abundant of all oystercatchers and the best studied. The main breeding and wintering areas are centered on the North Sea, but the distribution covers the European Atlantic coast to as far south as Ghana

  18. Similar local, but different systemic, metabolomics responses of closely related pine subspecies to folivory by caterpillars of the processionary moth

    Energy Technology Data Exchange (ETDEWEB)

    Rivas-Ubach, A. [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland WA USA; CSIC, Global Ecology Unit CREAF-CEAB-CSIC-UAB, Cerdanyola del Vallès, Catalonia Spain; Cerdanyola del Vallès, CREAF, Catalonia Spain; Sardans, J. [CSIC, Global Ecology Unit CREAF-CEAB-CSIC-UAB, Cerdanyola del Vallès, Catalonia Spain; Cerdanyola del Vallès, CREAF, Catalonia Spain; Hódar, J. A. [Grupo de Ecología Terrestre, Departamento de Biología Animal y Ecología, Facultad de Ciencias, Universidad de Granada, Granada Spain; Garcia-Porta, J. [Institute of Evolutionary Biology, CSIC-Universitat Pompeu Fabra, Barcelona Spain; Guenther, A. [Department of Earth System Science, University of California, Irvine CA USA; Global Change Research Centre, Academy of Sciences of the Czech Republic, Brno Czech Republic; Oravec, M. [Global Change Research Centre, Academy of Sciences of the Czech Republic, Brno Czech Republic; Urban, O. [Global Change Research Centre, Academy of Sciences of the Czech Republic, Brno Czech Republic; Peñuelas, J. [CSIC, Global Ecology Unit CREAF-CEAB-CSIC-UAB, Cerdanyola del Vallès, Catalonia Spain; Cerdanyola del Vallès, CREAF, Catalonia Spain; Leiss, K.

    2016-05-16

    Plants respond locally and systemically to herbivore attack. Most of the research conducted on plant-herbivore relationships at elemental and molecular levels have focused on nutrients or/and certain molecular compounds or specific families of defensive metabolites showing that herbivores tend to select plant individuals or species with higher nutrient concentrations and to avoid those with higher levels of phenolics and terpenes. Unfortunately, the defensive role of phenolics in conifers is still unclear. We performed stoichiometric and metabolomics, local and systemic, analyses in two subspecies of Pinus sylvestris under the herbivorous attack by the caterpillars of the pine processionary moth, an important pest in the Mediterranean Basin. Herbivorous attack was not associated with any of the elements analyzed. Both pine subspecies responded locally to folivory mainly by increasing the concentrations of various terpenes and phenolics. Systemic responses differed between subspecies and most of the metabolites presented intermediate concentrations between those of the affected parts and unattacked trees. Contrary as usually thought, foliar nutrient concentrations did not show to be a main factor of an alleged plant selection by adult female processionary moths for oviposition. Local increases in phenolics were more associated with antioxidant function for protection against oxidative damage produced by folivory. On the other hand, terpenes were directly related to defense against herbivores. Herbivory attack produced a general systemic shift in pines, including both primary and secondary metabolisms, that was, however, less intense and chemically different from the local responses. Subspecies responded similarly locally but differently to folivory at systemic level.

  19. Streptococcus dysgalactiae subsp. equisimilis Isolated From Infections in Dogs and Humans: Are Current Subspecies Identification Criteria accurate?

    Science.gov (United States)

    Ciszewski, Marcin; Zegarski, Kamil; Szewczyk, Eligia M

    2016-11-01

    Streptococcus dysgalactiae is a pyogenic species pathogenic both for humans and animals. Until recently, it has been considered an exclusive animal pathogen causing infections in wild as well as domestic animals. Currently, human infections are being reported with increasing frequency, and their clinical picture is often similar to the ones caused by Streptococcus pyogenes. Due to the fact that S. dysgalactiae is a heterogeneous species, it was divided into two subspecies: S. dysgalactiae subsp. equisimilis (SDSE) and S. dysgalactiae subsp. dysgalactiae (SDSD). The first differentiation criterion, described in 1996, was based on strain isolation source. Currently applied criteria, published in 1998, are based on hemolysis type and Lancefield group classification. In this study, we compared subspecies identification results for 36 strains isolated from clinical cases both in humans and animals. Species differentiation was based on two previously described criteria as well as MALDI-TOF and genetic analyses: RISA and 16S rRNA genes sequencing. Antimicrobial susceptibility profiles were also determined according to CLSI guidelines. The results presented in our study suggest that the subspecies differentiation criteria previously described in the above two literature positions seem to be inaccurate in analyzed group of strains, the hemolysis type on blood agar, and Lancefield classification should not be here longer considered as criteria in subspecies identification. The antimicrobial susceptibility tests indicate emerging of multiresistant human SDSE strains resistant also to vancomycin, linezolid and tigecycline, which might pose a substantial problem in treatment.

  20. Two new species and one new subspecies of the South American catfish genus Corydoras (Pisces, Siluriformes, Callichthyidae)

    NARCIS (Netherlands)

    Nijssen, H.

    1971-01-01

    This paper contains descriptions and figures of two new species of Corydoras Lacépède, 1803, C. weitzmani from Peru, and C. blochi from Guyana, Brazil, and Venezuela. The latter species is represented by two subspecies, C. blochi blochi from the Amazonas, Branco, Orinoco, and Essequibo drainages,

  1. A new subspecies of sea snake, Hydrophis platurus xanthos, from Golfo Dulce, Costa Rica.

    Science.gov (United States)

    Bessesen, Brooke L; Galbreath, Gary J

    2017-01-01

    We describe a distinctive new subspecies of sea snake from the occasionally anoxic inner-basin waters of Golfo Dulce, Costa Rica, based on combined data garnered between 2010 and 2017 for 154 specimens, 123 free-ranging and 31 museum-held. The yellow sea snake, Hydrophis platurus xanthos Bessesen & Galbreath, subsp. n. , is diagnosed by a notably smaller body size and nearly uniform yellow coloration, which contrasts with the black and yellow striae and tail spots or bands typical of the species. Within the modest geographic range (circa 320 km 2 ), nearly all specimens possess both diagnostic character states. Bathymetrics appear to restrict genetic flow between this allopatric population and conspecifics in the broader Eastern Pacific. In perspicuous contrast to typical H. platurus , H. p. xanthos shows no association with drift lines, and feeds at night in turbulent waters, assuming a sinusoidal ambush posture never previously reported for the species. This evolutionarily significant unit (ESU) warrants taxonomic recognition and active protection.

  2. Flight activity and responses to climatic conditions of two subspecies of Melipona marginata Lepeletier (Apidae, Meliponinae)

    Energy Technology Data Exchange (ETDEWEB)

    Kleinert-Giovannini, A.; Imperatriz-Fonseca, V.L.

    1986-01-01

    The flight activity of two colonies of M. m. marginata and six colonies of M. m. obscurior was studied in Sao Paulo, Brazil during three periods in 1981-1983. All colonies were hived except for one colony of M. m. obscurior which nested in a hollow tree. The two subspecies showed the same responses to the climatic factors analyzed. Flight activity was correlated positively with temperature and negatively with RH. In favorable conditions foraging took place throughout the day but both species were most active between 11 and 13 h. In the last observation period (October 1982-January 1983), when only two obscurior colonies were studied, flight activity was not correlated to RH, occurring even when RH was unfavorably high. This was a very rainy season, and it is suggested that the behavior of the bees indicates a flexible response to prevailing weather conditions.

  3. Activation of persistent Streptococcus equi subspecies zooepidemicus in mares with subclinical endometritis

    DEFF Research Database (Denmark)

    Petersen, Morten Rønn; Skive, Bolette; Christoffersen, Mette

    2015-01-01

    Endometritis in horses caused by Streptococcus equi subspecies zooepidemicus (S. zooepidemicus) may be underdiagnosed due to traditional diagnostic methods lacking sensitivity and specificity. We serendipitously identified a bacterial growth medium (bActivate) that appeared capable of inducing...... negative for S. zooepidemicus on a low-volume uterine lavage, be negative on endometrial cytology and without clinical signs of endometritis to be included in the investigation. The mares were instilled with bActivate or PBS in the uterus. Growth of S. zooepidemicus was induced by bActivate in 64% (16...... penicillin resistance, but seemed to tolerate the antimicrobial due to dormancy. This is, to our knowledge, the first description of controlled growth induction of dormant bacteria from a subclinical infection. Moreover we demonstrated how endometritis can origin from a reservoir of dormant bacteria residing...

  4. Detection of Streptococcus equi subspecies equi using a triplex qPCR assay.

    Science.gov (United States)

    Webb, Katy; Barker, Colin; Harrison, Tihana; Heather, Zoe; Steward, Karen F; Robinson, Carl; Newton, J Richard; Waller, Andrew S

    2013-03-01

    Genome sequencing data for Streptococcus equi subspecies equi and zooepidemicus were used to develop a novel diagnostic triplex quantitative PCR (qPCR) assay targeting two genes specific to S. equi (eqbE and SEQ2190) and a unique 100 base pair control DNA sequence (SZIC) inserted into the SZO07770 pseudogene of S. zooepidemicus strain H70. This triplex strangles qPCR assay can provide results within 2h of sample receipt, has an overall sensitivity of 93.9% and specificity of 96.6% relative to the eqbE singlex assay and detects S. equi at levels below the threshold of the culture assay, even in the presence of contaminating bacteria. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Use of a novel serological test for exposure to Streptococcus equi subspecies equi in hospitalised horses.

    Science.gov (United States)

    Knowles, E J; Mair, T S; Butcher, N; Waller, A S; Wood, J L N

    2010-03-06

    Thirty horses with no external signs of strangles were tested for exposure to Streptococcus equi subspecies equi (S equi) using a new, commercially available serological test. The horses were also tested for persistent carriage of S equi by endoscopy of the guttural pouches and PCR analysis of lavage samples. The owners were questioned about the recent medical history of the horses. Serology suggested that four horses had been recently exposed to S equi. None of the horses had a known history of strangles but three of the four seropositive horses had recently shown non-specific signs of respiratory disease. One asymptomatic horse was positive for S equi by PCR, but none had both guttural pouch abnormalities and a positive PCR result. Ten additional horses known to have strangles were all seropositive by the serological test.

  6. Transmission of Streptococcus equi subspecies zooepidemicus infection from horses to humans.

    Science.gov (United States)

    Pelkonen, Sinikka; Lindahl, Susanne B; Suomala, Päivi; Karhukorpi, Jari; Vuorinen, Sakari; Koivula, Irma; Väisänen, Tia; Pentikäinen, Jaana; Autio, Tiina; Tuuminen, Tamara

    2013-07-01

    Streptococcus equi subspecies zooepidemicus (S. zooepidemicus) is a zoonotic pathogen for persons in contact with horses. In horses, S. zooepidemicus is an opportunistic pathogen, but human infections associated with S. zooepidemicus are often severe. Within 6 months in 2011, 3 unrelated cases of severe, disseminated S. zooepidemicus infection occurred in men working with horses in eastern Finland. To clarify the pathogen's epidemiology, we describe the clinical features of the infection in 3 patients and compare the S. zooepidemicus isolates from the human cases with S. zooepidemicus isolates from horses. The isolates were analyzed by using pulsed-field gel electrophoresis, multilocus sequence typing, and sequencing of the szP gene. Molecular typing methods showed that human and equine isolates were identical or closely related. These results emphasize that S. zooepidemicus transmitted from horses can lead to severe infections in humans. As leisure and professional equine sports continue to grow, this infection should be recognized as an emerging zoonosis.

  7. A Case of Disseminated Infection Caused by Streptococcus equi Subspecies zooepidemicus

    Directory of Open Access Journals (Sweden)

    Marie-France Poulin

    2009-01-01

    Full Text Available Human infections with Streptococcus equi subspecies zooepidemicus, a group C streptococcus, are very rare and are generally associated with contact with horses, and consumption of unpasteurized milk products, goat cheese or pork. In most cases S zooepidemicus leads to fulminant infections. The case of a middle-aged woman who had sporadic contact with horses is described in the present report. She developed a bacteremia with severe and extensive complications that included meningitis, mitral endocarditis and blindness due to bilateral endophthalmitis. To the authors’ knowledge, this is the first reported case of an endophthalmitis due to S zooepidemicus. Because of a penicillin allergy, the patient was treated with ceftriaxone and rifampin over six weeks and survived. The present case report highlights the severe complications associated with S zooepidemicus infection.

  8. Purulent meningoventriculitis caused by Streptococcus equi subspecies zooepidemicus in a snow leopard (Panthera uncia).

    Science.gov (United States)

    Yamaguchi, R; Nakamura, S; Hori, H; Kato, Y; Une, Y

    2012-01-01

    Streptococcus equi subspecies zooepidemicus (SEZ) is a zoonotic pathogen that causes respiratory tract infections in man and animals. SEZ infections are very rare in felids. This report describes purulent meningoventriculitis caused by SEZ in an approximately 16-year-old male snow leopard (Panthera uncia). The animal exhibited neurological signs and died 1 month after their onset. On necropsy examination, the surface blood vessels of the brain were swollen and there was an increased volume and turbidity of cerebrospinal fluid (CSF). Microscopically, suppurative inflammation accompanied by gram-positive cocci was observed in the meninges and near the ventricles. SEZ was isolated from the brain tissue and CSF. This is the first report of infection with SEZ in a felid other than a domestic cat. This animal had not had direct contact with horses, but it had been fed horse flesh that may have been the source of infection. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Life history attributes of Arizona Grasshopper Sparrow (Ammodramus savannarum ammolegus) and comparisons with other North American subspecies

    Science.gov (United States)

    Ruth, Janet M.

    2017-01-01

    Ammodramus savannarum ammolegus—commonly referred to as the Arizona Grasshopper Sparrow—occurs in the desert and plains grasslands of southeastern Arizona, southwestern New Mexico, and northern Sonora, Mexico. Although a subspecies of conservation concern, this is the first intensive study of its life history and breeding ecology, providing baseline data and facilitating comparisons with other North American Grasshopper Sparrow subspecies. Specifically, I found A. s. ammolegus males generally weighed less than other subspecies (16.0 ± 0.8 g) but with intermediate exposed culmen length (11.6 ± 0.5 mm) and wing chord length similar to the other two migratory subspecies (62.7 ± 1.5 mm). Territory size for A. s. ammolegus was 0.72 ± 0.37 ha, with some variation between sites and among years, possibly indicating variation in habitat quality across spatial and temporal scales. The return rate for A. s. ammolegus males was 39.2%. Nest initiation for A. s. ammolegus was early to mid-July after the monsoons had begun. Domed nests were constructed on the ground, primarily under native bunch grasses, and frequently with a tunnel extending beyond the nest rim, with nest openings oriented north. Clutch size was 3.97 ± 0.68, with no evidence of Brown-headed Cowbird (Molothrus ater) nest parasitism. Extreme climate factors in the arid Southwest may have affected the life history and morphology of A. s. ammolegus as compared to other subspecies, influencing body size and mass, culmen length, breeding phenology, and nest orientation. Other geographic variation occurred in return rates, clutch size, and nest parasitism rates. The baseline data for A. s. ammolegus obtained in this study will inform future taxonomic and ecological studies as well as conservation planning. Comparisons of A. s. ammolegus morphometrics with those of other subspecies will assist field biologists in distinguishing among subspecies where they overlap, especially on wintering grounds.

  10. 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

  11. Seasonal and geographic variation of southern blue whale subspecies in the Indian Ocean.

    Directory of Open Access Journals (Sweden)

    Flore Samaran

    Full Text Available Understanding the seasonal movements and distribution patterns of migratory species over ocean basin scales is vital for appropriate conservation and management measures. However, assessing populations over remote regions is challenging, particularly if they are rare. Blue whales (Balaenoptera musculus spp are an endangered species found in the Southern and Indian Oceans. Here two recognized subspecies of blue whales and, based on passive acoustic monitoring, four "acoustic populations" occur. Three of these are pygmy blue whale (B.m. brevicauda populations while the fourth is the Antarctic blue whale (B.m. intermedia. Past whaling catches have dramatically reduced their numbers but recent acoustic recordings show that these oceans are still important habitat for blue whales. Presently little is known about the seasonal movements and degree of overlap of these four populations, particularly in the central Indian Ocean. We examined the geographic and seasonal occurrence of different blue whale acoustic populations using one year of passive acoustic recording from three sites located at different latitudes in the Indian Ocean. The vocalizations of the different blue whale subspecies and acoustic populations were recorded seasonally in different regions. For some call types and locations, there was spatial and temporal overlap, particularly between Antarctic and different pygmy blue whale acoustic populations. Except on the southernmost hydrophone, all three pygmy blue whale acoustic populations were found at different sites or during different seasons, which further suggests that these populations are generally geographically distinct. This unusual blue whale diversity in sub-Antarctic and sub-tropical waters indicates the importance of the area for blue whales in these former whaling grounds.

  12. Sequencing and comparative genome analysis of two pathogenic Streptococcus gallolyticus subspecies: genome plasticity, adaptation and virulence.

    Directory of Open Access Journals (Sweden)

    I-Hsuan Lin

    Full Text Available Streptococcus gallolyticus infections in humans are often associated with bacteremia, infective endocarditis and colon cancers. The disease manifestations are different depending on the subspecies of S. gallolyticus causing the infection. Here, we present the complete genomes of S. gallolyticus ATCC 43143 (biotype I and S. pasteurianus ATCC 43144 (biotype II.2. The genomic differences between the two biotypes were characterized with comparative genomic analyses. The chromosome of ATCC 43143 and ATCC 43144 are 2,36 and 2,10 Mb in length and encode 2246 and 1869 CDS respectively. The organization and genomic contents of both genomes were most similar to the recently published S. gallolyticus UCN34, where 2073 (92% and 1607 (86% of the ATCC 43143 and ATCC 43144 CDS were conserved in UCN34 respectively. There are around 600 CDS conserved in all Streptococcus genomes, indicating the Streptococcus genus has a small core-genome (constitute around 30% of total CDS and substantial evolutionary plasticity. We identified eight and five regions of genome plasticity in ATCC 43143 and ATCC 43144 respectively. Within these regions, several proteins were recognized to contribute to the fitness and virulence of each of the two subspecies. We have also predicted putative cell-surface associated proteins that could play a role in adherence to host tissues, leading to persistent infections causing sub-acute and chronic diseases in humans. This study showed evidence that the S. gallolyticus still possesses genes making it suitable in a rumen environment, whereas the ability for S. pasteurianus to live in rumen is reduced. The genome heterogeneity and genetic diversity among the two biotypes, especially membrane and lipoproteins, most likely contribute to the differences in the pathogenesis of the two S. gallolyticus biotypes and the type of disease an infected patient eventually develops.

  13. [A new subspecies of Heraclides androgeus (Lepidoptera: Papilionidae) and its biogeographical aspects].

    Science.gov (United States)

    Vargas-Fernández, Isabel; Luis-Martínez, Armando; Llorente-Bousquets, Jorge

    2013-06-01

    A new subspecies of Heraclides androgeus (Lepidoptera: Papilionidae) and its biogeographical aspects. Heraclides androgeus epidaurus was described and illustrated by Godman & Salvin in 1890 based on specimens obtained in Veracruz, indicating that their distribution encompassed both the Pacific and Atlantic sides of Mexico. Later authors commented that there were morphological differences between the male wings from both populations. We analyzed, described and nominated Heraclides androgeus reyesorum ssp. nov. Vargas, Llorente & Luis distributed in the Mexican Pacific coast, based on 62 specimens, and compared it with H a. epidaurus from the Gulf of Mexico, based on more than 200 specimens housed at UNAM: Museo de Zoología, Facultad de Ciencias and the Colección Nacional de Insectos of the Instituto de Biologia, as well as some collections from the USA. The main characters were the width of the yellow and black bands on forewings in males, which had a significant difference between the populations of both sides of Mexico, although some characters were variable and showed partial overlap. In the hindwings, the differences were the extent of the subterminal lunules in dorsal and ventral view. We also analyzed the male genitalia, finding notorious differences in both sclerotic processes of the harpe. Subspecific differences between females refer to the brightness and extent of green spots on the hindwings and the extent of lunules in the ventral view. The greatest abundance of H. a. reyesorum ssp. nov. was in the tropical deciduous forest, with gallery forest and in the lower range of the cloud forest, present at altitudes of 500-800 m and 1000-1 750 m, respectively. We discussed the pattern of endemism due to historical vicariant processes and explain the presence of the new subspecies of H. androgeus and other taxa of specific level.

  14. Removal of Mycobacterium avium subspecies hominissuis (MAH) from drinking water by coagulation, flocculation and sedimentation processes.

    Science.gov (United States)

    Wong, E A; Shin, G-A

    2015-03-01

    There has been a growing concern over human exposure to Mycobacterium avium subspecies hominissuis (MAH) through drinking water due to its ubiquitous presence in natural waters and remarkable resistance to both chemical and physical disinfectants in drinking water treatment processes. However, little is known about the effectiveness of physico-chemical water treatment processes to remove MAH. Therefore, we determined the removal of MAH by alum coagulation, flocculation and sedimentation processes in optimized drinking water treatment conditions using standard jar test equipment. Contrary to the prevailing hypothesis, the results of this study show that removal of MAH by coagulation, flocculation and sedimentation processes was only moderate (approx. 0.65 log10) under low turbidity treatment conditions and the removal of MAH was actually lower than that of Escherichia coli (reference bacterium) in all the waters tested. Overall, the results of this study suggested that coagulation, flocculation and sedimentation processes may not be a reliable treatment option for removing MAH, and more efforts to find an effective control measures against MAH should be made to reduce the risk of MAH infection from drinking water. Despite a growing concern over human exposure to Mycobacterium avium subspecies hominissuis (MAH) through drinking water and its remarkable resistance to water disinfectants, little is known about the effectiveness of physico-chemical water treatment processes to remove MAH. Contrary to the prevailing hypothesis, the results of this study suggest that coagulation, flocculation and sedimentation processes may not be a reliable treatment option for MAH removal. As these processes have been the last remaining conventional drinking water treatment processes that might be effective against MAH, more efforts should be urgently made to find an effective control measures against this important waterborne pathogen. © 2014 The Society for Applied Microbiology.

  15. Subspecies of Hypolepis rugosula (Dennstaedtiaceae; Pteridophyta around the world: morphological and biogeographic perspectives

    Directory of Open Access Journals (Sweden)

    Pedro Bond Schwartsburd

    2014-06-01

    Full Text Available The "Hypolepis rugosula complex" has been the subject of great debate among pteridologists: some have considered H. rugosula a single subcosmopolitan (or circum-Antarctic species, whereas others have considered it a species-complex, encompassing several species. In the 1920s and 1930s, four geographically distinct varietiesof H. rugosula were recognized. In this work, we present a new taxonomy (with new combinations and statuses, as well as typification and full synonymy, together with complete distribution data for the species, with an infraspecific classification based on morphological and biogeographic perspectives. Hypolepis rugosula occurs in southern temperate regions and high-elevation tropical regions of the Americas, Africa (including Madagascar, Oceania and the Philippines, as well as in some isolated oceanic volcanic islands (e.g., Saint Helena and Tristan da Cunha. Here, 15 geographically distinct subspecies are recognized. All subspecies are geographically segregated from each other, except in New Zealand, where two occur sympatrically-possibly due to two different arrival and colonization times. Four patterns of "indument" (referring to catenate and glandular hairs collectively are distinguished. Different lineages are successful in their respective habitats; we observed two lineages with different ploidy levels (tetraploid and octoploid. Although long-distance dispersal is the best explanation for the extant distribution of H. rugosula;we do not exclude vicariance as a possible explanation for their occurrence on the land masses that were once united as Gondwana. Therefore, we are assuming that a fern species could remain unchanged for more than 70 Myr, and we are adopting the refugia theory, albeit with a different focus.

  16. Seasonal and Geographic Variation of Southern Blue Whale Subspecies in the Indian Ocean

    Science.gov (United States)

    Samaran, Flore; Stafford, Kathleen M.; Branch, Trevor A.; Gedamke, Jason; Royer, Jean-Yves; Dziak, Robert P.; Guinet, Christophe

    2013-01-01

    Understanding the seasonal movements and distribution patterns of migratory species over ocean basin scales is vital for appropriate conservation and management measures. However, assessing populations over remote regions is challenging, particularly if they are rare. Blue whales (Balaenoptera musculus spp) are an endangered species found in the Southern and Indian Oceans. Here two recognized subspecies of blue whales and, based on passive acoustic monitoring, four “acoustic populations” occur. Three of these are pygmy blue whale (B.m. brevicauda) populations while the fourth is the Antarctic blue whale (B.m. intermedia). Past whaling catches have dramatically reduced their numbers but recent acoustic recordings show that these oceans are still important habitat for blue whales. Presently little is known about the seasonal movements and degree of overlap of these four populations, particularly in the central Indian Ocean. We examined the geographic and seasonal occurrence of different blue whale acoustic populations using one year of passive acoustic recording from three sites located at different latitudes in the Indian Ocean. The vocalizations of the different blue whale subspecies and acoustic populations were recorded seasonally in different regions. For some call types and locations, there was spatial and temporal overlap, particularly between Antarctic and different pygmy blue whale acoustic populations. Except on the southernmost hydrophone, all three pygmy blue whale acoustic populations were found at different sites or during different seasons, which further suggests that these populations are generally geographically distinct. This unusual blue whale diversity in sub-Antarctic and sub-tropical waters indicates the importance of the area for blue whales in these former whaling grounds. PMID:23967221

  17. 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.

  18. Assessment of hybridization among wild and cultivated Vigna unguiculata subspecies revealed by arbitrarily primed polymerase chain reaction analysis.

    Science.gov (United States)

    Vijaykumar, Archana; Saini, Ajay; Jawali, Narendra

    2012-01-01

    Intra-species hybridization and incompletely homogenized ribosomal RNA repeat units have earlier been reported in 21 accessions of Vigna unguiculata from six subspecies using internal transcribed spacer (ITS) and 5S intergenic spacer (IGS) analyses. However, the relationships among these accessions were not clear from these analyses. We therefore assessed intra-species hybridization in the same set of accessions. Arbitrarily primed polymerase chain reaction (AP-PCR) analysis was carried out using 12 primers. The PCR products were resolved on agarose gels and the DNA fragments were scored manually. Genetic relationships were inferred by TREECON software using unweighted paired group method with arithmetic averages (UPGMA) cluster analysis evaluated by bootstrapping and compared with previous analyses based on ITS and 5S IGS. A total of 202 (86 %) fragments were found to be polymorphic and used for generating a genetic distance matrix. Twenty-one V. unguiculata accessions were grouped into three main clusters. The cultivated subspecies (var. unguiculata) and most of its wild progenitors (var. spontanea) were placed in cluster I along with ssp. pubescens and ssp. stenophylla. Whereas var. spontanea were grouped with ssp. alba and ssp. tenuis accessions in cluster II, ssp. alba and ssp. baoulensis were included in cluster III. Close affinities of ssp. unguiculata, ssp. alba and ssp. tenuis suggested inter-subspecies hybridization. Multi-locus AP-PCR analysis reveals that intra-species hybridization is prevalent among V. unguiculata subspecies and suggests that grouping of accessions from two different subspecies is not solely due to the similarity in the ITS and 5S IGS regions but also due to other regions of the genome.

  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. Subspecies identification of Chimpanzees Pan troglodytes (Primates: Hominidae from the National Zoo of the Metropolitan Park of Santiago, Chile, using mitochondrial DNA sequences

    Directory of Open Access Journals (Sweden)

    J.A. Vega

    2014-05-01

    Full Text Available Natural populations of Chimpanzees Pan troglodytes are declining because of hunting and illegal live animal trafficking. Four subspecies of Chimpanzee have been reported: Pan troglodytes troglodytes, P.t. schweinfurthii, P.t. verus and P.t. ellioti, which have remained geographically separated by natural barriers such as the rivers Niger, Sanaga and Ubangi in central Africa. Sequence analysis of mitochondrial DNA (mtDNA has been used for the determination of these subspecies, which indirectly can also suggest their geographic origin. It was decided to identify the subspecies and the geographic origin of three captive chimpanzees of the National Zoo of the Metropolitan Park of Santiago (Chile, by analyzing their mitochondrial DNA. DNA was extracted from the saliva of three adult chimpanzees (two males and one female. After the analysis of sequences of the mitochondrial hypervariable region (HVI, a phylogenetic tree was constructed using mitochondrial sequences of known Pan troglodytes subspecies. Molecular phylogeny analysis revealed that the chimpanzees are likely to belong to three different subspecies: P.t. schweinfurthii, P.t. verus and P.t. troglodytes. Identification of subspecies of the three chimpanzees of the National Zoo of the Metropolitan Park of Santiago (Chile was possible due to mtDNA analysis. Future identification of chimpanzees will allow the development of a studbook for the chimpanzee subspecies in other Latin American zoos.

  5. Comparative analysis of fliC Gene from Salmonella enterica sub-species for biosensor probe design and phylogenetic tree construction

    Directory of Open Access Journals (Sweden)

    Sunderamurthe Satisvar

    2017-06-01

    Full Text Available In tandem to the Salmonellosis infection worldwide, a study was conducted to determine the conserved and nonconserved region in Salmonella enterica sub-species so that it can be used to design probes in biosensors for the detection of Salmonella enterica as a species or sub-species distinctively. The region was selected for this study through fliC gene that is present in all Salmonella sub-species, encodes the Salmonella flagella or flagellin determines the serotype due to its H antigen and provides virulence to the bacteria. All sub-species were analyzed in a group of six and then analyzed individually in groups of two with all possible combinations to determine the overlapping regions. Based on the study, the predominant conserved region for S. enterica sub-species is between 103 and 158, whereas the non-conserved region is from 1245 to 1285. A phylogenetic tree was constructed for the S. enterica sub-species to determine the evolution of the Salmonella sub-species.

  6. 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

  7. 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

  8. 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

  9. [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.

  10. 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 ...

  11. 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...

  12. 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.

  13. 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...

  14. EFEKTIVITAS Bacillus thuringiensis H-14 STRAIN LOKAL DALAM BUAH KELAPA TERHADAP LARVA Anopheles sp dan Culex sp di KAMPUNG LAUT KABUPATEN CILACAP

    Directory of Open Access Journals (Sweden)

    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

  15. 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

  16. 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

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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

  3. 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...

  4. 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)

  5. 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

  6. 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

  7. 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...

  8. 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

  9. 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.

  10. 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...

  11. [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.

  12. 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

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. 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.