The Bacillus thuringiensis S1/4 strain was previously found to harbour vip1S, vip2S, and vip3 genes. Its plasmid curing led to the obtaining of four partially cured strains S1/4-2, S1/4-3, S1/4-7, and S1/4-9 (vip2S-vip1S (-), vip3 (+)), one strain S1/4-4 (vip2S-vip1S (+), vip3 (-)), and S1/4-0 strain lacking the three genes. Using these derivative strains as templates, PCR amplification and southern blot assay revealed that vip2S-vip1S operon and vip3 gene were localized on two different large plasmids. Bioinformatics studies showed that vip2S (1.356 kb), and vip1S (2.637 kb) genes are encoding by an operon consisting of two ORFs separated by an intergenic spacer of 4bp. Using the InterPro tool, Vip2S was found to belong to the family of Binary exotoxin A and Vip1S to bacterial exotoxin B. In silico modeling indicated that the 3D structure of Vip2S is a mixed α/β protein and proposed 3D-model of Vip1S. Bioassays of the partially cured strains supernatants showed a weak toxicity of S1/4-4 to the lepidopteran Spodoptera littoralis comparing to a better effect of S1/4-2, S1/4-3, S1/4-7, and S1/4-9, suggesting its eventual contribution to the toxicity. Nevertheless, the concentrated supernatant of S1/4-4 strain was not toxic against the coleopteran Tribolium castaneum.
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http://dx.doi.org/10.1016/j.ijbiomac.2016.06.003 | DOI Listing |
Med Vet Entomol
January 2025
Entomology Research Unit, Department of Zoology, The University of Burdwan, Burdwan, India.
Culicoides oxystoma Kieffer (Diptera: Ceratopogonidae) transmits many pathogens, including seven viruses, four protozoa and one nematode. This species has a wide distribution range across northern Afro-tropical, Palearctic, Australian, Indo-Malayan realms with a broad host spectrum, including cattle, buffaloes, sheep, pigs, dogs, horses and even humans. The heterogeneous nature of Culicoides' blood-feeding patterns is well documented, but the influence of various host blood meal sources on gut bacterial composition remains scant.
View Article and Find Full Text PDFPest Manag Sci
January 2025
Department of Plant Protection, Federal University of Santa Maria, Santa Maria, Brazil.
Background: Crocidosema aporema (Walsingham 1914) has historically been the main bud borer species in soybean in Brazil; however, a recent study reported that this species is not C. aporema but an undescribed species. In recent seasons, injury by Crocidosema sp.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China; National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China; Western Agricultural Research Center, Chinese Academy of Agricultural Sciences, Changji 831100, China. Electronic address:
The widespread commercialization of genetically modified (GM) crops makes it important to assess the potential impact of Bacillus thuringiensis (Bt) on non-target organisms. Pardosa astrigera is an important predator in agroforestry ecosystems, and female and male spiders may react differently to Bt toxins due to their different activity habits and nutritional requirements. In this study, we found that exposure to Cry2Aa protein did not affect the survival and body weight of P.
View Article and Find Full Text PDFInsects
December 2024
Programa de Pós-Graduação em Biodiversidade e Saúde, Instituto Oswaldo Cruz-Fundação Oswaldo Cruz (IOC/FIOCRUZ), Rio de Janeiro 21040-900, RJ, Brazil.
The high pathogenic activity of () strains against various insect orders has positioned it as the most effective, environmentally safe, and sustainable approach to integrated insect management. We aimed to identify strains capable of effectively controlling the housefly , a species of significant medical, veterinary, and public health concern. Twelve strains from Macapá, Brazil, were tested against housefly larvae.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China.
Horizontal gene transfer (HGT) plays a pivotal role in bacterial evolution, shaping the genetic diversity of bacterial populations. It can occur through mechanisms such as conjugation, transduction, and natural transformation. , a model Gram-positive bacterium, serves not only as a robust system for studying HGT but also as a versatile organism with established industrial applications, such as producing industrial enzymes, antibiotics, and essential metabolites.
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