| cloning, characterization and diversity of insecticidal crystal protein genes of bacillus thuringiensis native isolates from soils of andaman and nicobar islands. | bt strains were isolated from soils of andaman and nicobar islands and characterized by microscopic and molecular methods. diversity was observed both in protein and cry gene profiles, where majority of the isolates showed presence of 65 kda protein band on sds-page while rest of them showed 130, 72, 44, and 29 kda bands. pcr analysis revealed predominance of cry1i and cry7, 8 genes in these isolates. the pcr screening strategy presented here led us to identify putative novel cry genes which cou ... | 2011 | 21858696 |
| 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. | 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 ... | 2011 | 22182611 |
| Molecular characterization of Bacillus thuringiensis isolated from diverse habitats of India. | Bacillus thuringiensis (Bt) strains were isolated from 94 samples from different geographical regions. Novel types of crystalline inclusion bodies were observed from some of the isolates. Crystalline inclusions of bipyramidal, spherical and cuboidal morphology were found produced by most of the isolates. Isolate GS12 showed crystal on one side of spore while isolate GM108 formed crystals on both termini of spore. Isolate GN31 produced large sized bipyramidal crystals. SDS-PAGE analysis of the sp ... | 2011 | 22144134 |
| single molecule fluorescence study of the bacillus thuringiensis toxin cry1aa reveals tetramerization. | pore-forming toxins constitute a class of potent virulence factors that attack their host membrane in a two- or three-step mechanism. after binding to the membrane, often aided by specific receptors, they form pores in the membrane. pore formation either unfolds a cytolytic activity in itself or provides a pathway to introduce enzymes into the cells that act upon intracellular proteins. the elucidation of the pore-forming mechanism of many of these toxins represents a major research challenge. a ... | 2011 | 22006922 |
| effect on soil chemistry of genetically modified (gm) vs. non-gm maize. | the effects of genetically modified (gm) maize (zea mays l.) expressing the bacillus thuringiensis berliner cry1fa2 protein (bt) and phosphinothricin or glyphosate herbicide tolerance on soil chemistry (organic matter, n, p, k and ph), compared with non-gm controls, were assessed in field and pot experiments. in the field experiment, nh(4)(+) was significantly higher in soil under the crop modified for herbicide tolerance compared to the control (mean values of 11 and 9.6 mg n/kg respectively) w ... | 2010 | 21844670 |
| compositional equivalence of insect-protected glyphosate-tolerant soybean mon 87701 × mon 89788 to conventional soybean extends across different world regions and multiple growing seasons. | the soybean product mon 87701 × mon 89788 expresses both the cry1ac gene derived from bacillus thuringiensis and the cp4 epsps (5-enolpyruvylshikimate-3-phosphate synthase) gene derived from agrobacterium sp. strain cp4. each biotechnology-derived trait confers specific benefits of insect resistance and glyphosate tolerance, respectively. the purpose of this study was to compare the composition of seed and forage from this combined-trait product to those of conventional soybean grown in geog ... | 2011 | 21985102 |
| [characterization of bacillus thuringiensis sigk disruption mutant and its influence on activation of cry3a promoter]. | to construct and characterize a sigk gene disruption mutant of bacillus thuringiensis and to study influence of sigk gene disruption on the activation of cry3a gene promoter. | 2011 | 22126072 |
| Compatibility of garlic (Allium sativum L.) leaf agglutinin and Cry1Ac d-endotoxin for gene pyramiding. | d-Endotoxins produced by Bacillus thuringiensis (Bt) have been used as bio-pesticides for the control of lepidopteran insect pests. Garlic (Allium sativum L.) leaf agglutinin (ASAL), being toxic to several sap-sucking pests and some lepidopteran pests, may be a good candidate for pyramiding with d-endotoxins in transgenic plants for enhancing the range of resistance to insect pests. Since ASAL shares the midgut receptors with Cry1Ac in Helicoverpa armigera, there is possibility of antagonism in ... | 2011 | 21870043 |
| use of mixed cultures of biocontrol agents to control sheep nematodes. | biological control is a promising non-chemical approach for the control of gastrointestinal nematodes of sheep. use of combinations of biocontrol agents have been reported to be an effective method to increase the efficacy of biological control effects. in this study, combinations of either two bacillus thuringiensis (bt) or clonostachys rosea (c. rosea) isolates and bt+c. rosea isolates were evaluated in vitro in microtitre plates for their biocontrol activity on sheep nematodes. the baermann t ... | 2011 | 21962967 |
| Early warning of cotton bollworm resistance associated with intensive planting of Bt cotton in China. | Transgenic crops producing Bacillus thuringiensis (Bt) toxins kill some key insect pests, but evolution of resistance by pests can reduce their efficacy. The predominant strategy for delaying pest resistance to Bt crops requires refuges of non-Bt host plants to promote survival of susceptible pests. To delay pest resistance to transgenic cotton producing Bt toxin Cry1Ac, farmers in the United States and Australia planted refuges of non-Bt cotton, while farmers in China have relied on "natural" r ... | 2011 | 21857961 |
| Antibacterial activity of different degree of hydrolysis of palm kernel expeller peptides against spore-forming and non-spore-forming bacteria. | The goal of this study was to determine inhibitory effect of palm kernel expeller (PKE) peptides of different degree of hydrolysis (DH %) against spore-forming bacteria Bacillus cereus, Bacillus circulans, Bacillus coagulans, Bacillus licheniformis, Bacillus megaterium, Bacillus pumilus, Bacillus stearothermophillus, Bacillus subtilis, Bacillus thuringiensis, Clostridium perfringens; and non-spore-forming bacteria Escherichia coli, Lisinibacillus sphaericus, Listeria monocytogenes, Pseudomonas a ... | 2011 | 21848644 |
| Insect tolerance to the crystal toxins Cry1Ac and Cry2Ab is mediated by the binding of monomeric toxin to lipophorin glycolipids causing oligomerization and sequestration reactions. | Endotoxins from the soil bacterium Bacillus thuringiensis are used worldwide to control insect pests and vectors of diseases. Despite extensive use of the toxins as sprays and in transgenic crops, their mode of action is still not completely known. Here we show that two crystal toxins binding to different glycoprotein receptors have similar glycolipid binding properties. The glycolipid binding domain was identified in a recombinant peptide representing the domain II of the crystal toxin Cry1Ac ( ... | 2011 | 21925538 |
| Characterization of Bacillus thuringiensis soil isolates from Cuba, with insecticidal activity against mosquitoes. | Chemical insecticides may be toxic and cause environmental degradation. Consequently, biological control for insects represents an alternative with low ecological impact. In this work, three soil isolates (A21, A51 and C17) from different regions of the Cuban archipelago were identified, characterized and evaluated against Aedes aegypti and Culex quinquefasciatus. The new isolates were compared with reference IPS82 strain and two strains isolated from biolarvicides Bactivec and Bactoculicida, re ... | 2011 | 22017108 |
| Nanoscale imaging of Bacillus thuringiensis flagella using atomic force microscopy. | 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 ... | 2011 | 22159046 |
| [Coordinative compounds of zinc with N-substituted thiocarbamoil-N'-pentamethylensulfenamides--activity modifiers of enzymes of proteolytic and glycolytic action]. | The influence of a number of coordinative compounds of zinc with N-substituted thiocarbamoil-N'-pentamethylensulfenamides on activity of elastase, alpha-L-rhamnosidase and alpha-galactosidases evidence for a possibility of their usage as stimulators or inhibitors of enzymes tested have been studied. It was shown that all the compounds in concentration of 0.1 and 0.01% inhibited by 90-100% Bacillus thuringiensis 27-88Els+ elastase activity. [Zn(L2)Br2], [Zn(L1)(NCS)2] and [Zn(L3)(NCS)2] at 20 h e ... | 2011 | 21888052 |
| [Effects of Bt corn straw insecticidal proteins on enzyme activities of Eisenia fetida]. | Bacillus thuringiensis (Bt) proteins released from Bt corn can enter soil ecosystem via returning straw into field, root exudation, and pollen fluttering-down. In this study, the straws of Bt corn and its near-isogenic non-Bt line were added into soil with an application rate of 5% and 7.5% to breed Eisenia fetida, and the total protein content and the activities of acetylcholine esterase (AchE), glutathione peroxidase (GSH-PX), catalase (CAT), and superoxide dismutase (SOD) in E. fetida were de ... | 2011 | 22097378 |
| Bacillus thuringiensis Cry3Aa toxin increases the susceptibility of Crioceris quatuordecimpunctata to Beauveria bassiana infection. | The spotted asparagus beetle, Crioceris quatuordecimpunctata (Coleoptera: Chrysomelidae), is one of the most devastating pests of asparagus in China. Sprayed synthetic pesticides have been used to control C. quatuordecimpunctata damage, but they pose problems because of residues and harm to natural enemies. Neither the microbial coleopteran-specific toxin from Bacillus thuringiensistenebrionis, Cry3Aa, nor the fungal pathogen Beauveria bassiana have sufficient activity to effectively control C. ... | 2011 | 22200644 |
| differential protection of cry1fa toxin against spodoptera frugiperda larval gut proteases by cadherin orthologs correlates with increased synergism. | the cry proteins produced by bacillus thuringiensis (bt) are the most widely used biopesticides effective against a range of crop pests and disease vectors. like chemical pesticides, development of resistance is the primary threat to the long-term efficacy of bt toxins. recently discovered cadherin-based bt cry synergists showed the potential to augment resistance management by improving efficacy of cry toxins. however, the mode of action of bt cry synergists is thus far unclear. here we elucida ... | 2012 | 22081566 |
| transcription profiling of resistance to bti toxins in the mosquito aedes aegypti using next-generation sequencing. | the control of mosquitoes transmitting infectious diseases relies mainly on the use of chemical insecticides. however, resistance to most chemical insecticides threatens mosquito control programs. in this context, the spraying of toxins produced by the bacteria bacillus thuringiensis subsp. israelensis (bti) in larval habitats represents an alternative to chemical insecticides and is now widely used for mosquito control. recent studies suggest that resistance of mosquitoes to bti toxin may occur ... | 2011 | 22115744 |
| screening, diversity and partial sequence comparison of vegetative insecticidal protein (vip3a) genes in the local isolates of bacillus thuringiensis berliner. | characterization, direct sequencing of the pcr amplicon and phylogenetic relationship was done to discover a novel vip protein genes of the bt isolates, to improve the prospects for insect control, more vip proteins should be sought out and researched to predict their insecticidal activity. characterization was based on direct sequencing of pcr amplicon using primers specific to vip3a gene was presented here. 12 out of 18 isolates screened were positive for vip gene-specific primers. homology se ... | 2012 | 22246044 |
| comparison of the insecticide susceptibilities of laboratory strains of aedes aegypti and aedes albopictus. | a susceptible strain of aedes albopictus derived from the gainesville strain (florida, usa) was established in our laboratory. the larvicidal efficacies of the neurotoxic insecticides temephos, permethrin and the pure cis and trans-permethrin isomers and the microbial insecticide bacillus thuringiensis israelensis (bti) against ae. albopictus were estimated and compared to a susceptible strain of aedes aegypti. the larvicidal effect of insect growth regulator pyriproxyfen was also evaluated in b ... | 2011 | 22241122 |
| increased frequency of pink bollworm resistance to bt toxin cry1ac in china. | transgenic crops producing insecticidal proteins from bacillus thuringiensis (bt) kill some key insect pests, but evolution of resistance by pests can reduce their efficacy. the main approach for delaying pest adaptation to bt crops uses non-bt host plants as "refuges" to increase survival of susceptible pests. to delay evolution of pest resistance to transgenic cotton producing bt toxin cry1ac, the united states and some other countries have required refuges of non-bt cotton, while farmers in c ... | 2012 | 22238687 |
| [obtaining of water soluble microbial melanin and study of its some properties]. | the effective sorption method for melanin isolation and purification from fermentation solutions of bacillus thuringiensis serovar galleriae k1 has been elaborated, the principle process flowsheet is presented. the identification of obtained pigment with the samples of natural and synthetic melanin was done by ir-spectroscopy, and the intensity ratio of optical absorption at 650 and 500 nm allows to refer the isolated melanin to eumelanin class. by thermal treatment it was determined, that melan ... | 2011 | 22232896 |
| the 60-kda protein encoded by orf2 in the cry19a operon of bacillus thuringiensis subsp. jegathesan functions like a c-terminal crystallization domain. | the cry19a operon of bacillus thuringiensis subsp. jegathesan encodes two proteins, mosquitocidal cry19a (orf1, 75-kda), and orf2 (60-kda) of unknown function. expression of the cry19a operon in an acrystalliferous strain of b. thuringiensis (4q7) yielded one small crystal per cell, whereas no crystals were produced when cry19a or orf2 were expressed alone. to determine the function of the orf2 protein, different combinations of cry19a, orf2 and the n- or c-terminal half of cry1c were synthesize ... | 2012 | 22247140 |
| evaluation of organically acceptable insecticides as stand-alone treatments and in rotation for managing yellowmargined leaf beetle, microtheca ochroloma (coleoptera: chrysomelidae), in organic crucifer production. | background: yellowmargined leaf beetle, microtheca ochroloma, is the most damaging pest of organic crucifer crops in the southern united states. experiments were conducted over four growing seasons (2007-2010) in alabama to evaluate some botanical and microbial insecticides approved by the organic materials review institute (omri) against m. ochroloma in organically grown crucifer crops. insecticides evaluated included pyganic(®) (pyrethrum), aza-direct(®) (azadiractin), entrust(®) (spinosad) ... | 2012 | 22231993 |
| amino acids y229 and f603 are involved in bacillus thuringiensis cry1ac delta-endotoxin stability and toxicity. | bacillus thuringiensis cry1ac toxin shares structurally five conserved blocs with the other delta-endotoxins. in order to study the role of some amino acids belonging to these regions, two mutations, y(229) p and f(603) s, have been introduced separately and respectively in blocs 2 and 5. the resulting mutant proteins cry1ac'1 and cry1ac'3 were affected in their stability and crystallization. both of them lost their toxicity to the lepidopteran larvae ephestia kuehniella. unlike cry1ac'1, cry1ac ... | 2012 | 22268917 |
| field response of aboveground non-target arthropod community to transgenic bt-cry1ab rice plant residues in postharvest seasons. | risk assessments of ecological effects of transgenic rice expressing lepidoptera-cry proteins from bacillus thuringiensis (bt) on non-target arthropods have primarily focused on rice plants during cropping season, whereas few studies have investigated the effects in postharvest periods. harvested rice fallow fields provide a critical over-wintering habitat for arthropods in the chinese rice ecosystems, particularly in the southern region of the country. during 2006-08, two independent field tria ... | 2012 | 22252123 |
| co-expression and synergism analysis of vip3aa29 and cyt2aa3 insecticidal proteins from bacillus thuringiensis. | vegetative insecticidal protein (vip3) from bacillus thuringiensis shows high activity against lepidopteran insects. cytolytic δ-endotoxin (cyt) also has high toxicity to dipteran larvae and synergism with other crystal proteins (cry), but synergism between cyt and vip3 proteins has not been tested. we analyzed for synergism between cyt2aa3 and vip3aa29. both cyt2aa3 and vip3aa29 genes were co-expressed in escherichia coli strain bl21 carried on vector pcoladuet-1. vip3aa29 showed insecticidal a ... | 2012 | 22218570 |
| interaction of proteinase inhibitors with cry1ac toxicity and the presence of 15 chymotrypsin cdnas in the midgut of the tobacco budworm, heliothis virescens (f.) (lepidoptera: noctuidae). | background: the potential development of resistance to bacillus thuringiensis (bt) cotton and surging of non-targeted insects is a major risk in the durability of bt plant technology. midgut proteinases are involved in bt activation and degradation. proteinase inhibitors may be used to control a wide range of insects and delay bt resistance development. proactive action to examine proteinase inhibitors for synergistic interaction with bt toxin and cloning of proteinase cdnas for rnai is necessar ... | 2012 | 22228503 |
| large crystal toxin formation in chromosomally engineered bacillus thuringiensis subsp. aizawai was due to σe accumulation. | seven distinct bacillus thuringiensis subsp. aizawai (bta) integrants, were constructed by carrying the chitinase (chibla) gene from b. licheniformis under control of the cry11aa promoter and terminator with and without p19 and p20 genes. the toxicity of bta integrants against 2(nd) instar spodoptera litura larvae was increased 1.8-4.6 fold when compared to that of the wild type strain (bta1). surprisingly, the enhanced toxicity in some strains of bta integrants (btap19cs, btap19cster and btacat ... | 2012 | 22267677 |
| control of mosquito larvae in seasonal wetlands on a wildlife refuge using vectomax cg. | there is a great need for novel insecticides to control mosquitoes. vectomax is a new mosquito larvicide that combines toxins from bacillus thuringiensis subsp. israelensis (bti) and bacillus sphaericus (bs), and is designed to provide extended mosquito control. we tested the initial efficacy and longevity of control of mosquitoes using one of the formulations, vectomax cg, in a full-scale study conducted in seasonal wetlands. vectomax cg was applied by air at 8.9 kg/ha to 3 wetlands and 3 other ... | 2011 | 22329272 |
| evaluating the non-rice host plant species of sesamia inferens (lepidoptera: noctuidae) as natural refuges: resistance management of bt rice. | although rice (oryza sativa l.) lines that express bacillus thuringiensis (bt) toxins have shown great potential for managing the major lepidoptera pests of rice in southern china, including sesamia inferens, their long-term use is dependent on managing resistance development to bt toxins in pest populations. the maintenance of "natural" refuges, non-bt expressing plants that are hosts for a target pest, has been proposed as a means to minimize the evolution of resistance to bt toxins in transge ... | 2011 | 22251655 |
| the effect of seston on mortality of simulium vittatum (diptera: simuliidae) from insecticidal proteins produced by bacillus thuringiensis subsp. israelensis. | water was collected from a site on the susquehanna river in eastern pennsylvania, where less-than-optimal black fly larval mortality had been occasionally observed after treatment with bacillus thuringiensis subsp. israelensis de barjac insecticidal crystalline proteins (bti icps). a series of experiments was conducted with simulium vittatum zetterstedt larvae to determine the water related factors responsible for the impaired response to bti icps (vectobac 12s, strain am 65-52). seston in the w ... | 2011 | 22217757 |
| early murine immune responses from endotracheal exposures to biotechnology-related bacillus strains. | an immunology-based in vivo screening regime was used to assess the potential pathogenicity of biotechnology-related microbes. strains of bacillus cereus (bc), bacillus subtilis (bs), bacillus thuringiensis (bt), and bt commercial products (cps) were tested. balb/c mice were endotracheally instilled with purified spores, diluted cp, or vegetative cells (vc) (live or dead). exposed mice were evaluated for changes in behavioral and physical symptoms, bacterial clearance, pulmonary granulocytes, an ... | 2011 | 23087536 |
| new combinations of cry genes from bacillus thuringiensis strains isolated from northwestern mexico. | twenty eight bacillus thuringiensis strains isolated from the tijuana-ensenada region of northwestern mexico were analyzed to determine the distribution of cry and cyt genes. crystal production by the strains was examined by scanning electron microscopy, which showed the predominance of cubic crystals. alkaline-dissolved and trypsin activated crystals were also analyzed by sds-page, yielding bands of 40-200 kda. the cry1 and cry2 genes were molecularly characterized using general and newly desig ... | 2012 | 23844480 |
| in vitro ovicidal and cestocidal effects of toxins from bacillus thuringiensis on the canine and human parasite dipylidium caninum. | bacillus thuringiensis is a gram-positive soil-dwelling bacterium that is commonly used as a biological pesticide. this bacterium may also be used for biological control of helminth parasites in domestic animals. in this study, we evaluated the possible ovicidal and cestocidal effects of a total protein extract of b. thuringiensis native strains on the zoonotic cestode parasite of dogs, dipylidium caninum (d. caninum). dose and time response curves were determined by coincubating b. thuringiensi ... | 2012 | 23484087 |
| analysis of the bacterial diversity existing on animal hide and wool: development of a preliminary pcr-restriction fragment length polymorphism fingerprint database for identifying isolates. | twenty-one bacterial strains were isolated from imported cattle hide and rabbit wool using two types of media, nutrient broth, and nutrient broth with serum. the bacteria identified were brevibacillus laterosporus, leclercia adecarboxylata, peptococcus niger, bacillus circulans, raoultella ornithinolytica, bacillus subtilis, bacillus cereus, bacillus thermobacillus, bacillus choshinensis, bacillus sphaericus, acinetobacter haemolyticus, sphingomonas paucimobilis, bacillus thuringiensis, staphylo ... | 2012 | 23451394 |
| anti-fungi activities of bacillus thuringiensis h3 chitinase and immobilized chitinase particles and their effects to rice seedling defensive enzymes. | the chitinase producing bacterium h3 strain was screened from nature with the selective medium and was identified as bacillus thuringiensis. the purpose of this investigation is to study the antifungi activity of bacillus thuringiensis h3 chitinase and its immobilized particles, and the effects on growth of rice seedlings and activities of defensive enzymes. the rice seedlings qualities and several defense enzymes activity were measured after rice seedlings were treated by free chitinase and imm ... | 2012 | 23421182 |
| comparative evaluation of phenoloxidase activity in different larval stages of four lepidopteran pests after exposure to bacillus thuringiensis. | microbial entomopathogen-based bioinsecticides are recognized as alternatives to synthetic pesticides. insects defend themselves against microbial pathogens by innate mechanisms, including increased phenoloxidase (po) activity, but its relationship with microbial bioinsecticides efficacy is little known. this study evaluated the differences in po activity at different developmental stages of the tobacco budworm heliothis virescens fabricius (lepidoptera: noctuidae), indian meal moth plodia inter ... | 2012 | 23414117 |
| dynamic staining of bacillus endospores with thioflavin t. | rapid detection and identification of endospores presents a range of complex challenges. dynamic staining approach, developed in our lab, utilizes the time-course fluorescence enhancement of an amyloid-staining dye, thioflavin t (tht), after mixing with intact endospores. we examined the kinetics of staining bacillus atrophaeus and bacillus thuringiensis endospores, and the rates of staining were different for the two bacilli when intact endospores were treated with tht. this finding demonstrate ... | 2012 | 23365938 |
| genetic structure and gene flow among brazilian populations of heliothis virescens (lepidoptera: noctuidae). | population genetic studies are essential to the better application of pest management strategies, including the monitoring of the evolution of resistance to insecticides and genetically modified plants. bacillus thuringiensis berliner (bt) crops have been instrumental in controlling tobacco budworm, heliothis virescens (f.) (lepidoptera: noctuidae), a pest that has developed resistance to many common insecticides once used for its management. in our study, microsatellite markers were applied to ... | 2012 | 23356080 |
| interaction between the predator podisus nigrispinus (hemiptera: pentatomidae) and the entomopathogenic bacteria bacillus thuringiensis. | plutella xylostella (l.) is susceptible to both the entomopathogen bacillus thuringiensis and the predator, brazilian spined soldier bug [podisus nigrispinus (dallas)]. the objective of this study was to measure the interaction between the bacterium b. thuringiensis and the predator p. nigrispinus. we also studied the behavior of p. nigrispinus in relation to its choice between b. thuringiensis-infected and healthy p. xylostellais larvae. in the first treatment, p. nigrispinus nymphs were fed da ... | 2012 | 23321092 |
| production of a thermostable and alkaline chitinase by bacillus thuringiensis subsp. kurstaki strain hbk-51. | this paper reports the isolation and identification of chitinase-producing bacillus from chitin-containing wastes, production of a thermostable and alkaline chitinasese, and enzyme characterization. bacillus thuringiensis subsp. kurstaki hbk-51 was isolated from soil and was identified. chitinase was obtained from supernatant of b. thuringiensis hbk-51 strain and showed its optimum activity at 110°c and at ph 9.0. following 3 hours of incubation period, the enzyme showed a high level of activity ... | 2012 | 23304523 |
| selectivity and self-assembly in the control of a bacterial toxin by an antitoxic noncoding rna pseudoknot. | bacterial small rnas perform numerous regulatory roles, including acting as antitoxic components in toxin-antitoxin systems. in type iii toxin-antitoxin systems, small processed rnas directly antagonize their toxin protein partners, and in the systems characterized the toxin and antitoxin components together form a trimeric assembly. in the present study, we sought to define how the rna antitoxin, toxi, inhibits its potentially lethal protein partner, toxn. we show through cross-inhibition exper ... | 2012 | 23267117 |
| computational modeling deduced three dimensional structure of cry1ab16 toxin from bacillus thuringiensis ac11. | the first theoretical structural model of newly reported cry1ab16 δ-endotoxin produced by bacillus thuringiensis ac11 was predicted using homology modeling technique. cry1ab16 resembles the cry1aa protein structure by sharing a common three domains structure responsible in pore forming and specificity determination along with few structural deviations. the main differences between the two is in the length of loops, absence of α7b, α9a, α10b, α11a and presence of additional β12b, α13 components w ... | 2011 | 23729892 |
| residual effects of tmof-bti formulations against 1(st) instar aedes aegypti linnaeus larvae outside laboratory. | to evaluate the effectiveness and residual effects of trypsin modulating oostatic factor-bacillus thuringiensis israeliensis (tmof-bti) formulations against aedes aegypti (ae. aegypti) (l.) larvae at ukm campus kuala lumpur. | 2012 | 23569922 |
| toxicity and affecting factors of bacillus thuringiensis var. israelensis on chironomus kiiensis larvae. | 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. kiiens ... | 2012 | 23465075 |
| promise for plant pest control: root-associated pseudomonads with insecticidal activities. | insects are an important and probably the most challenging pest to control in agriculture, in particular when they feed on belowground parts of plants. the application of synthetic pesticides is problematic owing to side effects on the environment, concerns for public health and the rapid development of resistance. entomopathogenic bacteria, notably bacillus thuringiensis and photorhabdus/xenorhabdus species, are promising alternatives to chemical insecticides, for they are able to efficiently k ... | 2013 | 23914197 |
| arbuscular mycorrhizal fungal spores host bacteria that affect nutrient biodynamics and biocontrol of soil-borne plant pathogens. | the aim of this research was to isolate and characterize bacteria from spores of arbuscular mycorrhizal fungi (amf). we designated these bacteria 'probable endobacteria' (pe). three bacterial strains were isolated from approximately 500 spores of gigaspora margarita (becker and hall) using a hypodermic needle (diameter, 200 μm). the bacteria were identified by morphological methods and on the basis of ribosomal gene sequences as bacillus sp. (ktcigm01), bacillus thuringiensis (ktcigm02), and pae ... | 2011 | 23213368 |
| hydrogen and polyhydroxybutyrate producing abilities of bacillus spp. from glucose in two stage system. | metabolic activities of four bacillus strains to transform glucose into hydrogen (h(2)) and polyhydroxybutyrate (phb) in two stages were investigated in this study. under batch culture conditions, bacillus thuringiensis egu45 and bacillus cereus egu44 evolved 1.67-1.92 mol h(2)/mol glucose, respectively during the initial 3 days of incubation at 37°c. in the next 2 days, the residual glucose solutions along with b. thuringiensis egu45 shaken at 200 rpm was found to produce phb yield of 11.3% of ... | 2011 | 23024402 |
| ingestibility, digestibility, and engineered biological control potential of flavobacterium hibernum, isolated from larval mosquito habitats. | flavobacterium hibernum, isolated from larval habitats of the eastern tree hole mosquito, a. triseriatus, remained suspended in the larval feeding zone much longer (8 days) than other bacteria. autofluorescent protein markers were developed for the labeling of f. hibernum with a strong flavobacterial expression system. green fluorescent protein (gfp)-tagged f. hibernum cells were quickly consumed by larval mosquitoes at an ingestion rate of 9.5 × 10(4)/larva/h. the ingested f. hibernum cells wer ... | 2014 | 24296502 |
| functional screening of metagenome and genome libraries for detection of novel flavonoid-modifying enzymes. | the functional detection of novel enzymes other than hydrolases from metagenomes is limited since only a very few reliable screening procedures are available that allow the rapid screening of large clone libraries. for the discovery of flavonoid-modifying enzymes in genome and metagenome clone libraries, we have developed a new screening system based on high-performance thin-layer chromatography (hptlc). this metagenome extract thin-layer chromatography analysis (meta) allows the rapid detection ... | 2013 | 23686272 |
| evaluation of a microfluidic chip system for preparation of bacterial dna from swabs, air, and surface water samples. | the detection of bacterial pathogens from complex sample matrices by pcr requires efficient dna extraction. in this study, a protocol for extraction and purification of dna from swabs, air, and water samples using a microfluidic chip system was established. the optimized protocol includes a combination of thermal, chemical and enzymatic lysis followed by chip-based dna purification using magnetic particles. the procedure was tested using gram-positive bacillus thuringiensis berliner var. kurstak ... | 2016 | 27520284 |
| pen and pal are nucleotide-sugar dehydratases that convert udp-glcnac to udp-6-deoxy-d-glcnac-5,6-ene and then to udp-4-keto-6-deoxy-l-altnac for cmp-pseudaminic acid synthesis in bacillus thuringiensis. | cmp-pseudaminic acid is a precursor required for the o-glycosylation of flagellin in some pathogenic gram-negative bacteria, a process known to be critical in bacterial motility and infection. however, little is known about flagellin glycosylation in gram-positive bacteria. here, we identified and functionally characterized an operon, named bti_pse, in bacillus thuringiensis israelensis atcc 35646, which encodes seven different enzymes that together convert udp-glcnac to cmp-pseudaminic acid. in ... | 2014 | 25414257 |
| structural studies of a bacterial trna(his) guanylyltransferase (thg1)-like protein, with nucleotide in the activation and nucleotidyl transfer sites. | all nucleotide polymerases and transferases catalyze nucleotide addition in a 5' to 3' direction. in contrast, trna(his) guanylyltransferase (thg1) enzymes catalyze the unusual reverse addition (3' to 5') of nucleotides to polynucleotide substrates. in eukaryotes, thg1 enzymes use the 3'-5' addition activity to add g-1 to the 5'-end of trna(his), a modification required for efficient aminoacylation of the trna by the histidyl-trna synthetase. thg1-like proteins (tlps) are found in archaea, bacte ... | 2013 | 23844012 |
| purification and characterization of a novel cold shock protein-like bacteriocin synthesized by bacillus thuringiensis. | bacillus thuringiensis (bt), one of the most successful biopesticides, may expand its potential by producing bacteriocins (thuricins). the aim of this study was to investigate the antimicrobial potential of a novel bt bacteriocin, thuricin btcspb, produced by bt brc-zyr2. the results showed that this bacteriocin has a high similarity with cold-shock protein b (cspb). btcspb lost its activity after proteinase k treatment; however it was active at 60 °c for 30 min and was stable in the ph range 5- ... | 2016 | 27762322 |
| deep sequencing of the transcriptomes of soybean aphid and associated endosymbionts. | the soybean aphid has significantly impacted soybean production in the u.s. transcriptomic analyses were conducted for further insight into leads for potential novel management strategies. | 2012 | 22984624 |
| phages preying on bacillus anthracis, bacillus cereus, and bacillus thuringiensis: past, present and future. | many bacteriophages (phages) have been widely studied due to their major role in virulence evolution of bacterial pathogens. however, less attention has been paid to phages preying on bacteria from the bacillus cereus group and their contribution to the bacterial genetic pool has been disregarded. therefore, this review brings together the main information for the b. cereus group phages, from their discovery to their modern biotechnological applications. a special focus is given to phages infect ... | 2014 | 25010767 |
| field evolved resistance in helicoverpa armigera (lepidoptera: noctuidae) to bacillus thuringiensis toxin cry1ac in pakistan. | helicoverpa armigera (hübner) is one of the most destructive pests of several field and vegetable crops, with indiscriminate use of insecticides contributing to multiple instances of resistance. in the present study we assessed whether h. armigera had developed resistance to bt cotton and compared the results with several conventional insecticides. furthermore, the genetics of resistance was also investigated to determine the inheritance to cry1ac resistance. to investigate the development of re ... | 2012 | 23077589 |
| phospholipase a2 inhibitors synthesized by two entomopathogenic bacteria, xenorhabdus nematophila and photorhabdus temperata subsp. temperata. | the entomopathogenic bacteria xenorhabdus nematophila and photorhabdus temperata subsp. temperata suppress insect immune responses by inhibiting the catalytic activity of phospholipase a(2) (pla(2)), which results in preventing biosynthesis of immune-mediating eicosanoids. this study identified pla(2) inhibitors derived from culture broths of these two bacteria. both x. nematophila and p. temperata subsp. temperata culture broths possessed significant pla(2)-inhibitory activities. fractionation ... | 2012 | 22447611 |
| similar genetic basis of resistance to bt toxin cry1ac in boll-selected and diet-selected strains of pink bollworm. | genetically engineered cotton and corn plants producing insecticidal bacillus thuringiensis (bt) toxins kill some key insect pests. yet, evolution of resistance by pests threatens long-term insect control by these transgenic bt crops. we compared the genetic basis of resistance to bt toxin cry1ac in two independently derived, laboratory-selected strains of a major cotton pest, the pink bollworm (pectinophora gossypiella [saunders]). the arizona pooled resistant strain (azp-r) was started with pi ... | 2012 | 22530065 |
| insecticidal activity of bacillus thuringiensis cry1bh1 against ostrinia nubilalis (hubner) (lepidoptera: crambidae) and other lepidopteran pests. | bacillus thuringiensis is an important source of insect resistance traits in commercial crops. in an effort to prolong b. thuringiensis trait durability, insect resistance management programs often include combinations of insecticidal proteins that are not cross resistant or have demonstrable differences in their site of action as a means to mitigate the development of resistant insect populations. in this report, we describe the activity spectrum of a novel b. thuringiensis cry protein, cry1bh1 ... | 2013 | 24077715 |
| efficacy of genetically modified bt toxins alone and in combinations against pink bollworm resistant to cry1ac and cry2ab. | evolution of resistance in pests threatens the long-term efficacy of insecticidal proteins from bacillus thuringiensis (bt) used in sprays and transgenic crops. previous work showed that genetically modified bt toxins cry1abmod and cry1acmod effectively countered resistance to native bt toxins cry1ab and cry1ac in some pests, including pink bollworm (pectinophora gossypiella). here we report that cry1abmod and cry1acmod were also effective against a laboratory-selected strain of pink bollworm re ... | 2013 | 24244692 |
| combining hexanoic acid plant priming with bacillus thuringiensis insecticidal activity against colorado potato beetle. | interaction between insect herbivores and host plants can be modulated by endogenous and exogenous compounds present in the source of food and might be successfully exploited in colorado potato beetle (cpb) pest management. feeding tests with cpb larvae reared on three solanaceous plants (potato, eggplant and tomato) resulted in variable larval growth rates and differential susceptibility to bacillus thuringiensis cry3aa toxin as a function of the host plant. an inverse correlation with toxicity ... | 2013 | 23743826 |
| bacillus thuringiensis cry34ab1/cry35ab1 interactions with western corn rootworm midgut membrane binding sites. | bacillus thuringiensis (bt) cry34ab1/cry35ab1 are binary insecticidal proteins that are co-expressed in transgenic corn hybrids for control of western corn rootworm, diabrotica virgifera virgifera leconte. bt crystal (cry) proteins with limited potential for field-relevant cross-resistance are used in combination, along with non-transgenic corn refuges, as a strategy to delay development of resistant rootworm populations. differences in insect midgut membrane binding site interactions are one li ... | 2013 | 23308139 |
| structural and biophysical characterization of bacillus thuringiensis insecticidal proteins cry34ab1 and cry35ab1. | bacillus thuringiensis strains are well known for the production of insecticidal proteins upon sporulation and these proteins are deposited in parasporal crystalline inclusions. the majority of these insect-specific toxins exhibit three domains in the mature toxin sequence. however, other cry toxins are structurally and evolutionarily unrelated to this three-domain family and little is known of their three dimensional structures, limiting our understanding of their mechanisms of action and our a ... | 2014 | 25390338 |
| alternative splicing and highly variable cadherin transcripts associated with field-evolved resistance of pink bollworm to bt cotton in india. | evolution of resistance by insect pests can reduce the benefits of insecticidal proteins from bacillus thuringiensis (bt) that are used extensively in sprays and transgenic crops. despite considerable knowledge of the genes conferring insect resistance to bt toxins in laboratory-selected strains and in field populations exposed to bt sprays, understanding of the genetic basis of field-evolved resistance to bt crops remains limited. in particular, previous work has not identified the genes confer ... | 2014 | 24840729 |
| common virulence factors and tissue targets of entomopathogenic bacteria for biological control of lepidopteran pests. | this review focuses on common insecticidal virulence factors from entomopathogenic bacteria with special emphasis on two insect pathogenic bacteria photorhabdus (proteobacteria: enterobacteriaceae) and bacillus (firmicutes: bacillaceae). insect pathogenic bacteria of diverse taxonomic groups and phylogenetic origin have been shown to have striking similarities in the virulence factors they produce. it has been suggested that the detection of phage elements surrounding toxin genes, horizontal and ... | 2014 | 24634779 |
| multi-toxin resistance enables pink bollworm survival on pyramided bt cotton. | transgenic crops producing bacillus thuringiensis (bt) proteins kill key insect pests, providing economic and environmental benefits. however, the evolution of pest resistance threatens the continued success of such bt crops. to delay or counter resistance, transgenic plant "pyramids" producing two or more bt proteins that kill the same pest have been adopted extensively. field populations of the pink bollworm (pectinophora gossypiella) in the united states have remained susceptible to bt toxins ... | 2015 | 26559899 |
| analysis of bacillus thuringiensis population dynamics and its interaction with pseudomonas fluorescens in soil. | 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 ... | 2015 | 26495114 |
| is the efficacy of biological control against plant diseases likely to be more durable than that of chemical pesticides? | the durability of a control method for plant protection is defined as the persistence of its efficacy in space and time. it depends on (i) the selection pressure exerted by it on populations of plant pathogens and (ii) on the capacity of these pathogens to adapt to the control method. erosion of effectiveness of conventional plant protection methods has been widely studied in the past. for example, apparition of resistance to chemical pesticides in plant pathogens or pests has been extensively d ... | 2015 | 26284088 |
| host-pathogen coevolution: the selective advantage of bacillus thuringiensis virulence and its cry toxin genes. | reciprocal coevolution between host and pathogen is widely seen as a major driver of evolution and biological innovation. yet, to date, the underlying genetic mechanisms and associated trait functions that are unique to rapid coevolutionary change are generally unknown. we here combined experimental evolution of the bacterial biocontrol agent bacillus thuringiensis and its nematode host caenorhabditis elegans with large-scale phenotyping, whole genome analysis, and functional genetics to demonst ... | 2015 | 26042786 |
| transgenic maize event tc1507: global status of food, feed, and environmental safety. | maize (zea mays) is a widely cultivated cereal that has been safely consumed by humans and animals for centuries. transgenic or genetically engineered insect-resistant and herbicide-tolerant maize, are commercially grown on a broad scale. event tc1507 (oecd unique identifier: das-ø15ø7-1) or the herculex®(#) i trait, an insect-resistant and herbicide-tolerant maize expressing cry1f and pat proteins, has been registered for commercial cultivation in the us since 2001. a science-based safety asses ... | 2015 | 26018138 |
| cross-resistance and interactions between bt toxins cry1ac and cry2ab against the cotton bollworm. | to delay evolution of pest resistance to transgenic crops producing insecticidal proteins from bacillus thuringiensis (bt), the "pyramid" strategy uses plants that produce two or more toxins that kill the same pest. we conducted laboratory diet experiments with the cotton bollworm, helicoverpa armigera, to evaluate cross-resistance and interactions between two toxins in pyramided bt cotton (cry1ac and cry2ab). selection with cry1ac for 125 generations produced 1000-fold resistance to cry1ac and ... | 2015 | 25586723 |
| the pesticidal cry6aa toxin from bacillus thuringiensis is structurally similar to hlye-family alpha pore-forming toxins. | the cry6 family of proteins from bacillus thuringiensis represents a group of powerful toxins with great potential for use in the control of coleopteran insects and of nematode parasites of importance to agriculture. these proteins are unrelated to other insecticidal toxins at the level of their primary sequences and the structure and function of these proteins has been poorly studied to date. this has inhibited our understanding of these toxins and their mode of action, along with our ability t ... | 2016 | 27576487 |
| bacillus cereus biofilms-same, only different. | bacillus cereus displays a high diversity of lifestyles and ecological niches and include beneficial as well as pathogenic strains. these strains are widespread in the environment, are found on inert as well as on living surfaces and contaminate persistently the production lines of the food industry. biofilms are suspected to play a key role in this ubiquitous distribution and in this persistency. indeed, b. cereus produces a variety of biofilms which differ in their architecture and mechanism o ... | 2016 | 27458448 |
| field-evolved mode 1 resistance of the fall armyworm to transgenic cry1fa-expressing corn associated with reduced cry1fa toxin binding and midgut alkaline phosphatase expression. | insecticidal protein genes from the bacterium bacillus thuringiensis (bt) are expressed by transgenic bt crops (bt crops) for effective and environmentally safe pest control. the development of resistance to these insecticidal proteins is considered the most serious threat to the sustainability of bt crops. resistance in fall armyworm (spodoptera frugiperda) populations from puerto rico to transgenic corn producing the cry1fa insecticidal protein resulted, for the first time in the united states ... | 2016 | 26637593 |
| cytotoxicity analysis of three bacillus thuringiensis subsp. israelensis δ-endotoxins towards insect and mammalian cells. | 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. ... | 2012 | 23029407 |
| bacillus thuringiensis subsp. israelensis and its dipteran-specific toxins. | 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 f ... | 2014 | 24686769 |
| bacteriocins from the rhizosphere microbiome - from an agriculture perspective. | bacteria produce and excrete a versatile and dynamic suit of compounds to defend against microbial competitors and mediate local population dynamics. these include a wide range of broad-spectrum non-ribosomally synthesized antibiotics, lytic enzymes, metabolic by-products, proteinaceous exotoxins, and ribosomally produced antimicrobial peptides (bacteriocins). most bacteria produce at least one bacteriocin. bacteriocins are of interest in the food industry as natural preservatives and in the pro ... | 2015 | 26579159 |
| three novel lantibiotics, ticins a1, a3, and a4, have extremely stable properties and are promising food biopreservatives. | lantibiotics are antimicrobial peptides with potential applications as the next generation of antimicrobials in the food industry and/or the pharmaceutical industry. nisin has successfully been used as a food preservative for over 40 years, but its major drawback is its limited stability under neutral and alkaline ph conditions. to identify alternatives with better biochemical properties, we screened more than 100 strains of the bacillus cereus group. three novel lantibiotics, ticins a1 (4,062.9 ... | 2015 | 26231642 |
| identification of metabolism pathways directly regulated by sigma(54) factor in bacillus thuringiensis. | sigma(54) (σ(54)) regulates nitrogen and carbon utilization in bacteria. promoters that are σ(54)-dependent are highly conserved and contain short sequences located at the -24 and -12 positions upstream of the transcription initiation site. σ(54) requires regulatory proteins known as bacterial enhancer-binding proteins (bebps) to activate gene transcription. we show that σ(54) regulates the capacity to grow on various nitrogen sources using a bacillus thuringiensis hd73 mutant lacking the sigl g ... | 2015 | 26029175 |
| immune modulation enables a specialist insect to benefit from antibacterial withanolides in its host plant. | the development of novel plant chemical defenses and counter adaptations by herbivorous insect could continually drive speciation, producing more insect specialists than generalists. one approach to test this hypothesis is to compare closely related generalist and specialist species to reveal the associated costs and benefits of these different adaptive strategies. we use the specialized moth heliothis subflexa, which feeds exclusively on plants in the genus physalis, and its close generalist re ... | 2016 | 27561781 |
| thusin, a novel two-component lantibiotic with potent antimicrobial activity against several gram-positive pathogens. | due to the rapidly increasing prevalence of multidrug-resistant bacterial strains, the need for new antimicrobial drugs to treat infections has become urgent. bacteriocins, which are antimicrobial peptides of bacterial origin, are considered potential alternatives to conventional antibiotics and have attracted widespread attention in recent years. among these bacteriocins, lantibiotics, especially two-component lantibiotics, exhibit potent antimicrobial activity against some clinically relevant ... | 2016 | 27486447 |
| poly-β-hydroxybutyrate metabolism is unrelated to the sporulation and parasporal crystal protein formation in bacillus thuringiensis. | poly-3-hydroxybutyrate (phb) is a natural polymer synthesized by many bacteria as a carbon-energy storage material. it was accumulated maximally prior to the spore formation but was degraded during the process of sporulation in bacillus thuringiensis. intriguingly, b. thuringiensis also accumulates large amounts of insecticidal crystal proteins (icps) during sporulation, which requires considerable input of carbon and energy sources. how phb accumulation affects sporulation and icp formation rem ... | 2016 | 27379025 |
| a multi-enzymatic cascade reaction for the stereoselective production of γ-oxyfunctionalyzed amino acids. | a stereoselective three-enzyme cascade for synthesis of diasteromerically pure γ-oxyfunctionalized α-amino acids was developed. by coupling a dynamic kinetic resolution (dkr) using an n-acylamino acid racemase (naaar) and an l-selective aminoacylase from geobacillus thermoglucosidasius with a stereoselective isoleucine dioxygenase from bacillus thuringiensis, diastereomerically pure oxidized amino acids were produced from racemic n-acetylamino acids. the three enzymes differed in their optimal t ... | 2016 | 27092111 |
| importance of rare taxa for bacterial diversity in the rhizosphere of bt- and conventional maize varieties. | ribosomal 16s rrna gene pyrosequencing was used to explore whether the genetically modified (gm) bt-maize hybrid mon 89034 × mon 88017, expressing three insecticidal recombinant cry proteins of bacillus thuringiensis, would alter the rhizosphere bacterial community. fine roots of field cultivated bt-maize and three conventional maize varieties were analyzed together with coarse roots of the bt-maize. a total of 547,000 sequences were obtained. library coverage was 100% at the phylum and 99.8% at ... | 2012 | 22791236 |
| bacillus thuringiensis suppresses bacterial wilt disease caused by ralstonia solanacearum with systemic induction of defense-related gene expression in tomato. | bacillus thuringiensis is a naturally abundant gram-positive bacterium and a well-known, effective bio-insecticide. recently, b. thuringiensis has attracted considerable attention as a potential biological control agent for the suppression of plant diseases. in this study, the bacterial wilt disease-suppressing activity of b. thuringiensis was examined in tomato plants. treatment of tomato roots with b. thuringiensis culture followed by challenge inoculation with ralstonia solanacearum suppresse ... | 2012 | 23257909 |
| metagenomic analysis of the airborne environment in urban spaces. | the organisms in aerosol microenvironments, especially densely populated urban areas, are relevant to maintenance of public health and detection of potential epidemic or biothreat agents. to examine aerosolized microorganisms in this environment, we performed sequencing on the material from an urban aerosol surveillance program. whole metagenome sequencing was applied to dna extracted from air filters obtained during periods from each of the four seasons. the composition of bacteria, plants, fun ... | 2014 | 25351142 |
| genome sequence of the endophytic bacterium bacillus thuringiensis strain kb1, a potential biocontrol agent against phytopathogens. | italic! bacillus thuringiensisis the most widely known microbial pesticide used in agricultural applications. herein, we report a draft genome sequence of the endophytic bacterium italic! bacillus thuringiensisstrain kb1, which exhibits antagonism against phytopathogens. | 2016 | 27103716 |
| bacteriocins synthesized by bacillus thuringiensis: generalities and potential applications. | the members of the bacillus thuringiensis group, commonly known as bt, produce a huge number of metabolites, which show biocidal and antagonistic activity. b. thuringiensis is widely known for synthesizing cry, vip and cyt proteins, active against insects and other parasporins with biocidal activity against certain types of cancerous cells. nevertheless, b. thuringiensis also synthesizes compounds with antimicrobial activity, especially bacteriocins. some b. thuringiensis bacteriocins resemble l ... | 2016 | 27340340 |
| diffusible signal factor (dsf) quorum sensing signal and structurally related molecules enhance the antimicrobial efficacy of antibiotics against some bacterial pathogens. | extensive use of antibiotics has fostered the emergence of superbugs that are resistant to multidrugs, which becomes a great healthcare and public concern. previous studies showed that quorum sensing signal dsf (diffusible signal factor) not only modulates bacterial antibiotic resistance through intraspecies signaling, but also affects bacterial antibiotic tolerance through interspecies communication. these findings motivate us to exploit the possibility of using dsf and its structurally related ... | 2014 | 24575808 |
| structural differences in gut bacteria communities in developmental stages of natural populations of lutzomyia evansi from colombia's caribbean coast. | lutzomyia evansi, a phlebotomine insect endemic to colombia's caribbean coast, is considered to be the main vector of visceral and cutaneous leishmaniasis in the region. although insects of this species can harbor pathogenic and non-pathogenic microorganisms in their intestinal microbiota, there is little information available about the diversity of gut bacteria present in lutzomyia evansi. in this study, conventional microbiological methods and molecular tools were used to assess the compositio ... | 2016 | 27618991 |
| characterization of a natural triple-tandem c-di-gmp riboswitch and application of the riboswitch-based dual-fluorescence reporter. | c-di-gmp riboswitches are structured rnas located in the 5'-untranslated regions (5'-utrs) of mrnas that regulate expression of downstream genes in response to changing concentrations of the second messenger c-di-gmp. we discovered three complete c-di-gmp riboswitches (bc3, bc4 and bc5 rna) with similar structures, which are arranged in tandem to constitute a triple-tandem (bc3-5 rna) riboswitch in the 5'-utr of the cspabcde mrna in bacillus thuringiensis subsp. chinensis ct-43. our results show ... | 2016 | 26892868 |
| a transgenic approach to control hemipteran insects by expressing insecticidal genes under phloem-specific promoters. | the first generation transgenic crops used strong constitutive promoters for transgene expression. however, tissue-specific expression is desirable for more precise targeting of transgenes. moreover, piercing/sucking insects, which are generally resistant to insecticidal bacillus thuringiensis (bt) proteins, have emerged as a major pests since the introduction of transgenic crops expressing these toxins. phloem-specific promoters isolated from banana bunchy top virus (bbtv) were used for the exp ... | 2016 | 27708374 |
| excavating abiotic stress-related gene resources of terrestrial macroscopic cyanobacteria for crop genetic engineering: dawn and challenge. | genetically engineered (ge) crops with resistance to environmental stresses are one of the most important solutions for future food security. numerous genes associated to plant stress resistance have been identified and characterized. however, the current reality is that only a few transgenic crops expressing prokaryotic genes are successfully applied in field conditions. these few prokaryotic genes include agrobacterium strain cp4 epsps gene, bacillus thuringiensis cry1ab gene and a bacterial c ... | 2015 | 26418632 |
| activation of gab cluster transcription in bacillus thuringiensis by γ-aminobutyric acid or succinic semialdehyde is mediated by the sigma 54-dependent transcriptional activator gabr. | bacillus thuringiensis gabr is a sigma 54-dependent transcriptional activator containing three typical domains, an n-terminal regulatory domain per-arnt-sim (pas), a central aaa(+) (atpases associated with different cellular activities) domain and a c-terminal helix-turn-helix (hth) dna binding domain. gabr positively regulates the expression of the gabt gene of the gab gene cluster, which is responsible for the γ-aminobutyric acid (gaba) shunt. | 2014 | 25527261 |
| extended genetic analysis of brazilian isolates of bacillus cereus and bacillus thuringiensis. | multiple locus sequence typing (mlst) was undertaken to extend the genetic characterization of 29 isolates of bacillus cereus and bacillus thuringiensis previously characterized in terms of presence/absence of sequences encoding virulence factors and via variable number tandem repeat (vntr). additional analysis involved polymerase chain reaction for the presence of sequences (be, cytk, ina, pag, lef, cya and cap), encoding putative virulence factors, not investigated in the earlier study. mlst a ... | 2013 | 23440117 |
| a method for assessing efficiency of bacterial cell disruption and dna release. | dna-based testing is becoming the preferred method both for identifying microorganisms and for characterizing microbial communities. however, no single dna extraction method exists that is suitable for all types of microorganisms because bacteria are variable in their susceptibility to lysis by available extraction procedures. to develop and test new dna extraction procedures, it would be helpful to determine their efficiencies. while the amount of extracted dna can readily be measured by differ ... | 2016 | 27566276 |
| antimicrobial activity of anonna mucosa (jacq.) grown in vivo and obtained by in vitroculture. | brazilian flora includes numerous species of medicinal importance that can be used to develop new drugs. plant tissue culture offers strategies for conservation and use of these species allowing continuous production of plants and bioactive substances. annona mucosa has produced substances such as acetogenins and alkaloids that exhibit antimicrobial activities. the widespread use of antibiotics has led to an increase in multidrug-resistant bacteria, which represents a serious risk of infection. ... | 2015 | 26413061 |