scholarly journals Bacillus thuringiensis: An Environment Friendly Microbial Control Agent

2012 ◽  
Vol 2 (2) ◽  
pp. 36-51 ◽  
Author(s):  
Nishat Sarker ◽  
Khandaker Rayhan Mahbub
Keyword(s):  
Bacillus Thuringiensis ◽  
Microbial Control ◽  
Control Agent ◽  
Environment Friendly

scholarly journals Parasporal Body Formation via Overexpression of the Cry10Aa Toxin of Bacillus thuringiensis subsp. israelensis, and Cry10Aa-Cyt1Aa Synergism

2009 ◽  
Vol 75 (14) ◽  
pp. 4661-4667 ◽  
Author(s):  
Alejandro Hernández-Soto ◽  
M. Cristina Del Rincón-Castro ◽  
Ana M. Espinoza ◽  
Jorge E. Ibarra
Keyword(s):  
Bacillus Thuringiensis ◽  
Gradient Centrifugation ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Microbial Control ◽  
Control Agent ◽  
Mass Spectrometry Analysis ◽  
Parasporal Crystal ◽  
Spectrometry Analysis ◽  
Crystal Complex

ABSTRACT Bacillus thuringiensis subsp. israelensis is the most widely used microbial control agent against mosquitoes and blackflies. Its insecticidal success is based on an arsenal of toxins, such as Cry4A, Cry4B, Cry11A, and Cyt1A, harbored in the parasporal crystal of the bacterium. A fifth toxin, Cry10Aa, is synthesized at very low levels; previous attempts to clone and express Cry10Aa were limited, and no parasporal body was formed. By using a new strategy, the whole Cry10A operon was cloned in the pSTAB vector, where both open reading frames ORF1 and ORF2 (and the gap between the two) were located, under the control of the cyt1A operon and the STAB-SD stabilizer sequence characteristic of this vector. Once the acrystalliferous mutant 4Q7 of B. thuringiensis subsp. israelensis was transformed with this construct, parasporal bodies were observed by phase-contrast microscopy and transmission electron microscopy. Discrete, ca. 0.9-μm amorphous parasporal bodies were observed in the mature sporangia, which were readily purified by gradient centrifugation once autolysis had occurred. Pure parasporal bodies showed two major bands of ca. 68 and 56 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. These bands were further characterized by N-terminal sequencing of tryptic fragments using matrix-assisted laser desorption ionization-time of flight mass spectrometry analysis, which identified both bands as the products of ORF1 and ORF2, respectively. Bioassays against fourth-instar larvae of Aedes aegypti of spore-crystal complex and pure crystals of Cry10Aa gave estimated 50% lethal concentrations of 2,061 ng/ml and 239 ng/ml, respectively. Additionally, synergism was clearly detected between Cry10A and Cyt1A, as the synergistic levels (potentiation rates) were estimated at 13.3 for the mixture of Cyt1A crystals and Cry10Aa spore-crystal complex and 12.6 for the combination of Cyt1A and Cry10Aa pure crystals.

THE POTENTIAL OF BACTERIA FOR THE MICROBIAL CONTROL OF GRASSHOPPERS AND LOCUSTS

1997 ◽  
Vol 129 (S171) ◽  
pp. 147-156 ◽  
Author(s):  
B. Zelazny ◽  
M.S. Goettel ◽  
B. Keller
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Bacillus Thuringiensis ◽  
Serratia Marcescens ◽  
Schistocerca Gregaria ◽  
Locusta Migratoria ◽  
Microbial Control ◽  
Control Agent ◽  
Promising Agent ◽  
Laboratory Populations ◽  
The Many

AbstractBacteria have been implicated in disease epizootics observed in field populations and laboratory-reared locusts and grasshoppers. Two species [Serratia marcescens Bizio and Pseudomonas aeruginosa (Schroeter) Migula] consistently infect locusts when ingested with food and can spread in laboratory populations. However, research on developing these organisms for microbial control of locusts and grasshoppers begun in the 1950s has not been continued. In recent years strains of Bacillus thuringiensis Berliner have been studied for activity against locusts and grasshoppers. Results of additional trials by the authors are reported. Among 393 B. thuringiensis isolates and 93 preparations of other sporeforming bacteria fed to nymphs of Locusta migratoria (L.) and/or Schistocerca gregaria Forsk., none has shown any pathogenicity to the insects. The recent discovery of novel B. thuringiensis strains active against various diverse pests and the many properties of a sporeforming bacterium that satisfy the requirements for a microbial control agent, and the development of Serratia entomophila as a promising agent for control of grass grubs, provide incentive to continue the search for an orthopteran-active sporeforming bacterium and to re-investigate the potential of non-sporeforming bacterial pathogens as microbial control agents of grasshoppers and locusts.

INVITATION PAPER (C.P. ALEXANDER FUND): HISTORY OF BACILLUS THURINGIENSIS BERLINER RESEARCH AND DEVELOPMENT

1992 ◽  
Vol 124 (4) ◽  
pp. 587-616 ◽  
Author(s):  
Clayton C. Beegle ◽  
Takashi Yamamoto
Keyword(s):  
Bacillus Thuringiensis ◽  
Ostrinia Nubilalis ◽  
Microbial Control ◽  
The United States ◽  
Control Agent ◽  
Turn Of The Century ◽  
Insect Larvae ◽  
Commercial Development ◽  
Japanese Workers ◽  
History Of

AbstractThis review article starts with the discovery of Bacillus thuringiensis Berliner in Japan at the turn of the century and notes that the observations of the early Japanese workers clearly show that they were aware of the toxin-mediated nature of the activity of B. thuringiensis toward insect larvae. The early work in Europe with B. thuringiensis against Ostrinia nubilalis (Hubner) showed that the bacterium had promise as a microbial control agent. The commercial development of B. thuringiensis in France in the late 1930s, and in Eastern Europe and the United States in the 1950s, is traced.

scholarly journals Genome Sequence of the Mosquitocidal Bacillus thuringiensis Strain BR58, a Biopesticide Product Effective against the Coffee Berry Borer ( Hypothenemus hampei )

2015 ◽  
Vol 3 (6) ◽  
Author(s):  
Janaina Zorzetti ◽  
Ana P. S. Ricietto ◽  
Carlos R. M. da Silva ◽  
Ivan R. Wolf ◽  
Gislayne T. Vilas-Bôas ◽  
...  
Keyword(s):  
Bacillus Thuringiensis ◽  
Aedes Aegypti ◽  
Genome Sequence ◽  
Insect Pests ◽  
Draft Genome ◽  
Microbial Control ◽  
Control Agent ◽  
Hypothenemus Hampei ◽  
Coffee Berry ◽  
Thuringiensis Strain

Bacillus thuringiensis is an important microbial control agent against insect pests. The draft genome sequence of the Brazilian strain BR58 described here contains the insecticidal genes cry4A , cry4B , cry10A , cry11A , cry60A , cry60B , and cyt1A , which show toxicity to both Aedes aegypti and Hypothenemus hampei larvae.

scholarly journals Dissecting the Environmental Consequences of Bacillus thuringiensis Application for Natural Ecosystems

Toxins ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 355
Author(s):  
Maria E. Belousova ◽  
Yury V. Malovichko ◽  
Anton E. Shikov ◽  
Anton A. Nizhnikov ◽  
Kirill S. Antonets
Keyword(s):  
Bacillus Thuringiensis ◽  
Biological Control Agent ◽  
Control Agent ◽  
Plant Colonization ◽  
Natural Ecosystems ◽  
Terrestrial Invertebrates ◽  
Environmental Consequences ◽  
Local Plants ◽  
Complex Relationships ◽  
Bacteria And Fungi

Bacillus thuringiensis (Bt), a natural pathogen of different invertebrates, primarily insects, is widely used as a biological control agent. While Bt-based preparations are claimed to be safe for non-target organisms due to the immense host specificity of the bacterium, the growing evidence witnesses the distant consequences of their application for natural communities. For instance, upon introduction to soil habitats, Bt strains can affect indigenous microorganisms, such as bacteria and fungi, and further establish complex relationships with local plants, ranging from a mostly beneficial demeanor, to pathogenesis-like plant colonization. By exerting a direct effect on target insects, Bt can indirectly affect other organisms in the food chain. Furthermore, they can also exert an off-target activity on various soil and terrestrial invertebrates, and the frequent acquisition of virulence factors unrelated to major insecticidal toxins can extend the Bt host range to vertebrates, including humans. Even in the absence of direct detrimental effects, the exposure to Bt treatment may affect non-target organisms by reducing prey base and its nutritional value, resulting in delayed alleviation of their viability. The immense phenotypic plasticity of Bt strains, coupled with the complexity of ecological relationships they can engage in, indicates that further assessment of future Bt-based pesticides’ safety should consider multiple levels of ecosystem organization and extend to a wide variety of their inhabitants.

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