The neuropeptide F (NPF) signaling, comprising NPF and neuropeptide F receptor (NPFR), role in regulating insect behaviors and physiological processes. We cloned the genes encoding NPF and NPFR from Plutella xylostella, a notorious pest of cruciferous crops. Notably, the NPF gene produced two splicing variants, Px-NPF1 and Px-NPF2, with distinct expression patterns.
View Article and Find Full Text PDFThe β-type anti-Id (Ab2β) is considered to have potential for simulating the structure and function of the antigen. In this study, a β-type anti-Id (3A7 anti-I-GEAb) of the Cry1C toxin was captured from a GEAb library. Subsequently, a higher activity of mutant (3A7 mutant 8) was obtained from the mutagenesis library based on 3A7 anti-I-GEAb.
View Article and Find Full Text PDFUsing the amino acid sequences and analysis of selected known structures of Bt Cry toxins, Cry1Ab, Cry1Ac, Cry1Ah, Cry1B, Cry1C and Cry1F we specifically designed immunogens. After antibodies selection, broad-spectrum polyclonal antibodies (pAbs) and monoclonal antibody (namely 1A0-mAb) were obtained from rabbit and mouse, respectively. The produced pAbs displayed broad spectrum activity by recognizing Cry1 toxin, Cry2Aa, Cry2Ab and Cry3Aa with half maximal inhibitory concentration (IC) values of 0.
View Article and Find Full Text PDFBacillus thuringiensis (Bt) Cry2Aa is a member of the Cry pore-forming, 3-domain, toxin family with activity against both lepidopteran and dipteran insects. Although domains II and III of the Cry toxins are believed to represent the primary specificity determinant through specific binding to cell receptors, it has been proposed that the pore-forming domain I of Cry2Aa also has such a role. Thus, a greater understanding of the functions of Cry2Aa's different domains could potentially be helpful in the rational design of improved toxins.
View Article and Find Full Text PDFQuant Imaging Med Surg
March 2024
Background: Capturing the segmentation of blood vessels by a fundus camera is crucial for the medical evaluation of various retinal vascular issues. However, due to the complicated vascular structure and unclear clinical criteria, the precise segmentation of blood arteries remains very challenging.
Methods: To address this issue, we developed the upgraded multi-convolution block and squeeze and excitation based on the U-shape network (MCSE-U-net) model that segments retinal vessels using a U-shaped network.
The widespread use of toxins as insecticides has brought about resistance problems. Anti-idiotypic nanobody approaches provide new strategies for resistance management and toxin evolution. In this study, the monoclonal antibody generated against the receptor binding region Domain II of Cry2Aa toxin was used as a target to screen materials with insecticidal activity.
View Article and Find Full Text PDFThis study tried to generate anti-idiotypic antibodies (Ab2s) which mimic Cry2Aa toxin using a phage-display antibody library (2.8 × 10 CFU/mL). The latter was constructed from a mouse immunized with F (ab') fragments digested from anti-Cry2Aa polyclonal antibodies.
View Article and Find Full Text PDFBacillus thuringiensis (Bt) Cry toxins have been widely used in the development of genetically modified organisms (GMOs) for pest control. This work aimed to establish more cost effective and broader detection methods for commonly used Cry toxins. Using ligand blot and bio-layer interferometry, we confirmed that a recombinant toxin-binding fragments derived from Helicoverpa armigera cadherin-like protein (HaCad-TBR) could broadly bind Cry1Ab, Cry1Ac, Cry2Aa, and Cry2Ab with the affinity of 0.
View Article and Find Full Text PDFBacillus thuringiensis (Bt) Cry toxins have been widely used in the development of genetically modified organisms (GMOs) for pest control. This work aimed to establish more cost effective methods for used Cry2Aa toxins. Three immunoassay methods (IC-ELISA, DAS-ELISA, and CLEIA) were successfully developed in this work.
View Article and Find Full Text PDFBackground: Chemical exchange saturation transfer (CEST) is a promising method for the detection of biochemical alterations in cancers and neurological diseases. However, the sensitivity of the currently existing quantitative method for detecting ischemia needs further improvement.
Methods: To further improve the quantification of the CEST signal and enhance the CEST detection for ischemia, we used a quantitative analysis method that combines an inverse Z-spectrum analysis and a 5-pool Lorentzian fitting.
Sheng Wu Gong Cheng Xue Bao
February 2023
Bt Cry toxin is the mostly studied and widely used biological insect resistance protein, which plays a leading role in the green control of agricultural pests worldwide. However, with the wide application of its preparations and transgenic insecticidal crops, the resistance to target pests and potential ecological risks induced by the drive are increasingly prominent and attracting much attention. The researchers seek to explore new insecticidal protein materials that can simulate the insecticidal function of Bt Cry toxin.
View Article and Find Full Text PDFAnti-idiotypic antibodies (Ab2) are valuable tools that can be used for a better understanding of molecular mimicry and the immunological network. In this work, we showed a new application of a phage-displayed alpha-type Ab2 (Ab2α) to improve the sensitivity of an enzyme-linked immunosorbent assay (ELISA) detecting cyanobacterial toxin microcystin-LR (MC-LR). A monoclonal antibody (mAb) against MC-LR was used as an antigen to isolate binders in a camelid nanobody library.
View Article and Find Full Text PDFNew insecticidal genes and approaches for pest control are a hot research area. In the present study, we explored a novel strategy for the generation of insecticidal proteins. The midgut cadherin of () was used as a target to screen materials that have insecticidal activity.
View Article and Find Full Text PDFStaphylococcus aureus is a common food-borne pathogenic microorganism that poses a serious threat to food quality and safety, and can do harm to human health. In the past, researchers relied on antibiotics to control Staphylococcus aureus, though very effective, yet it was also worrying in the aspect of bio-safety. In fact, anti-idiotypic antibody (Anti-Id) shows its potential to mimic some of the structural and biological functions of antigens.
View Article and Find Full Text PDFIt is extremely imminent to study a new strategy to manage agricultural pest like Plutella xylostella (P. xylostella) which is currently resistant to most of pesticides, including three domain-Cry toxins from Bacillus thuringiensis (Bt). In this study, we reported a phage displayed single domain antibody screening from human domain antibody (DAb) library targeted on Spodoptera frugiperda 9 (Sf9) cells expressed Cry1Ac toxin receptor, ATP-dependent binding cassette transporter C2 in P.
View Article and Find Full Text PDFMicrocystin-LR (MC-LR) is one of the most worldwide harmful cyanobacterial toxins. A lots of antibodies against MC-LR have been generated and characterized. However, the knowledge about the epitopes of MC-LR was still limited.
View Article and Find Full Text PDFBackground: Broad use of insecticidal Cry proteins from Bacillus thuringiensis in biopesticides and transgenic crops has resulted in cases of practical field resistance, highlighting the need for novel approaches to insect control. Previously we described an anti-Cry1Ab idiotypic-antibody (B12-scFv) displaying toxicity against rice leafroller (Cnaphalocrocis medinalis) larvae, supporting the potential of antibodies for pest control. The goal of the present study was to generate insecticidal antibodies against diamondback moth (Plutella xylostella) larvae.
View Article and Find Full Text PDFPhoX is an extracellular alkaline phosphatase that is widely found in cyanobacteria and plays an important role in the conversion of extracellular organophosphorus into soluble inorganic phosphorus. However, the gene has not yet been experimentally confirmed to exist in bloom-forming species. In this study, we identified a putative gene (GenBank accession no.
View Article and Find Full Text PDFThe anti-idiotypic antibody is widely used in the field of immunology to simulate structural features or even induce the biological activity of antigens. In this study, we obtained seven anti-idiotypic single-chain variable fragments (scFv) antibodies of Cry2Aa toxin from a phage-displayed mutant library constructed using error-prone PCR technique. A mutant designated 2-12B showed the best binding ability amongst all anti-idiotypic scFv isolates to Plutella xylostella brush border membrane vesicles (BBMVs).
View Article and Find Full Text PDFMicrocystin-LR (MC-LR) is a high-toxic biohazard that pollutes ecological environment and agroproducts. In this study, a newly recombined genetically engineered antibody (AV-MV) with higher thermal stability and binding activity was designed by chain shuffling and based on our previously obtained anti-MC-LR scFv and nanobody. Based on AV-MV template, a capacity of 8.
View Article and Find Full Text PDFAppl Microbiol Biotechnol
September 2020
Pyrethroids are insecticides that are widely used in rural and urban areas worldwide. After entering the environment, pyrethroids are rapidly metabolized or degraded by various biological or abiotic methods. In this study, a single-chain variable fragment (scFv) which could simultaneously detect three pyrethroid metabolites was constructed based on a hybridoma raised against 3-phenoxybenzoic acid (3-PBA).
View Article and Find Full Text PDFColony is a key to Microcystis becoming a dominant population and forming blooms. To find the mechanism of colony formation, we investigated cell wall structures of colonial and unicellular strains. Results showed that colonial strains had significant surface layer protein (S-layer) on the surface of cells than unicellular strains by transmission electron microscopy.
View Article and Find Full Text PDFMicrocystin-LR (MC-LR) is one of common high-toxic biotoxins produced by cyanobacteria in waterbody. A high sensitive and convenient detection method is necessary for monitoring for MC-LR. To establish a high sensitive indirect competitive enzyme-linked immunosorbent assay (IC-ELISA) based on single chain variable fragment (scFv) for detecting MC-LR, 16 positive anti-MC-LR phage scFv particles were screened out from a MC-LR-immunized mouse phage scFv library, which was successfully constructed with the capacity of 8.
View Article and Find Full Text PDFMicrocystin-LR (MC-LR) is one of the most common biotoxin that pollutes water and agricultural products. The study aims to obtain the high sensitive anti-MC-LR single-chain antibody (scFv) for detecting MC-LR. Here, a MC-LR-immunized rabbit phage display scFv library with its capacity of 3.
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