1.Targeted innovative design of Bt Cry toxin insecticidal mimics.
Chongxin XU ; Yuan LIU ; Xiao ZHANG ; Xianjin LIU
Chinese Journal of Biotechnology 2023;39(2):446-458
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. This will help to escort the sustainable and healthy production of crops, and relieve the pressure of target pests' resistance to Bt Cry toxin to a certain extent. In recent years, the author's team has proposed that Ab2β anti-idiotype antibody has the property of mimicking antigen structure and function based on the "Immune network theory" of antibody. With the help of phage display antibody library and specific antibody high-throughput screening and identification technology, Bt Cry toxin antibody was designed as the coating target antigen, and a series of Ab2β anti-idiotype antibodies (namely Bt Cry toxin insecticidal mimics) were screened from the phage antibody library. Among them, the lethality of Bt Cry toxin insecticidal mimics with the strongest activity was close to 80% of the corresponding original Bt Cry toxin, showing great promise for the targeted design of Bt Cry toxin insecticidal mimics. This paper systematically summarized the theoretical basis, technical conditions, research status, and discussed the development trend of relevant technologies and how to promote the application of existing achievements, aiming to facilitate the research and development of green insect-resistant materials.
Insecticides/metabolism*
;
Bacillus thuringiensis
;
Endotoxins/pharmacology*
;
Bacillus thuringiensis Toxins/metabolism*
;
Hemolysin Proteins/pharmacology*
;
Bacterial Proteins/chemistry*
;
Plants, Genetically Modified/genetics*
;
Pest Control, Biological
2.A case of poisoning caused by intramuscular injection of esfenvalerate.
Jin LI ; Guang Min TANG ; Shi Zhao XIANG ; Ming Yang YANG ; Li YANG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2023;41(3):225-227
Esfenvalerate is a kind of commonly used highly effective pyrethroid insecticide. It is common for people who are poisoned by contact or misuse, but rarely reported for people who are poisoned by intramuscular injection. This paper reports a case of intramuscular injection of esfenvalerate in the Department of Infection, West China Hospital of Sichuan University in November 2021. The patient was intramuscularly injected with about 20 ml of esfenvalerate, inducing the sense of swelling and tingling, degeneration and necrosis of striated muscle tissue at the injection site, also liver function damage and other manifestations. The patient was discharged from hospital after rehydration, accelerating poison metabolism, anti-infection, liver protection and local puncture.
Humans
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Insecticides
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Injections, Intramuscular
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Pyrethrins
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Nitriles/metabolism*
3.Advances in receptor-mediated resistance mechanisms of Lepidopteran insects to Bacillus thuringiensis toxin.
Leilei LIU ; Peiwen XU ; Kaiyu LIU ; Wei WEI ; Zhongshen CHANG ; Dahui CHENG
Chinese Journal of Biotechnology 2022;38(5):1809-1823
Bacillus thuringiensis is widely used as an insecticide which is safe and environmentally friendly to humans and animals. One of the important insecticidal mechanisms is the binding of Bt toxins to specific toxin receptors in insect midgut and forming a toxin perforation which eventually leads to insect death. The resistance of target pests to Bt toxins is an important factor hampering the long-term effective cultivation of Bt crops and the continuous use of Bt toxins. This review summarizes the mechanism of insect resistance to Bt toxins from the perspective of important Bt toxin receptors in midgut cells of Lepidopteran insects, which may facilitate the in-depth study of Bt resistance mechanism and pest control.
Animals
;
Bacillus thuringiensis/genetics*
;
Bacillus thuringiensis Toxins
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Bacterial Proteins/metabolism*
;
Endotoxins/metabolism*
;
Hemolysin Proteins/metabolism*
;
Insecta/metabolism*
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Insecticide Resistance/genetics*
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Insecticides/pharmacology*
;
Pest Control, Biological
4.Microorganisms capable of degrading neonicotinoids and their metabolic pathways: a review.
Xingru CHEN ; Shiqi FANG ; Shuang WAN ; Wenwen ZHOU ; Chao SUN ; Jun LI
Chinese Journal of Biotechnology 2022;38(12):4462-4497
Neonicotinoid compounds are usually considered harmless and eco-friendly in terms of their targeted toxicity compared to that of pyrethroids and phosphorus-containing pesticides. However, overuse of neonicotinoid insecticides resulted in the accumulation of its residuals or intermediates in soil and water, which consequently affected beneficial insects as well as mammals, yielding pollution and secondary risks. This review summarized the recent advances in neonicotinoid degrading microorganisms and their metabolic diversity, with the aim to address the urgent need for degrading these insecticides. These advances may facilitate the development of controllable and reliable technologies for efficiently transforming neonicotinoid insecticides into value-added products by synthetic biology and metagenomics.
Animals
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Neonicotinoids/metabolism*
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Insecticides/metabolism*
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Soil
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Environmental Pollution
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Metabolic Networks and Pathways
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Mammals/metabolism*
5.Promoter detection and transcriptional analysis of the spinosad biosynthetic gene cluster.
Xiaozhou FENG ; Weishan WANG ; Xiaohui REN ; Xinli LIU ; Xiangzhao MAO ; Keqian YANG
Chinese Journal of Biotechnology 2013;29(7):914-926
Spinosad represents a new class of insecticides produced by Saccharopolyspora spinosa. To understand the transcription of the spinosad biosynthetic gene cluster, two promoter detection plasmids based on different reporter genes were constructed and used to detect 9 promoters in the spinosad biosynthetic gene cluster. In addition, the temporal transcriptional profiles of the corresponding genes controlled by the 9 promoters, together with 4 genes outside of the spinosad cluster but are required for the synthesis of sugars in spinosad, were examined by real-time PCR. The results indicate that the 9 spinosad biosynthetic genes were highly expressed at the stationary phase, which coincides with the accumulation of spinosad in the fermentation broth. Of particular note is that the transcription of the 4 sugar synthetic genes showed higher level at the exponential phase, suggesting the expression of sugar synthetic genes is not correlated with the spinosad synthetic genes. The data suggest that spinosad biosynthesis could be improved by engineering the expression pattern of the sugar synthetic genes that lie outside the spinosad gene cluster.
Drug Combinations
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Insecticides
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metabolism
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Macrolides
;
metabolism
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Multigene Family
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Plasmids
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Promoter Regions, Genetic
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Real-Time Polymerase Chain Reaction
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Saccharopolyspora
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genetics
;
metabolism
6.Comparison of codon optimizations of cry1Ah1 gene in rice.
Zongliang ZHOU ; Zhimin LIN ; Lili GENG ; Jun SU ; Changlong SHU ; Feng WANG ; Yanming ZHU ; Jie ZHANG
Chinese Journal of Biotechnology 2012;28(10):1184-1194
cry1Ah1, one of holo-type cry genes, cloned in this laboratory from Bacillus thuringiensis strain has been patented in China, and it encoded a protein with strong insecticidal activity against certain lepidopteran insect pests, such as Chilo suppressalis. cry1Ah1 gene is exhibiting good application prospects. In order to improve the expression level of cry1Ah1 gene in rice, and investigate the effect of codon usage preference of gene expression, we designed five different optimized schemes for cry1Ah1 insecticidal critical fragment in accordance with bias of rice codon, to improve G+C content, removed the shear signal and unstable factors. Optimized cry1Ah1 genes were transformed into Escherichia coli Rosetta (DE3) respectively, and 65 kDa polypeptides was expressed normally in inclusion body separately. All of these expressed polypeptides showed insecticidal activity against 2nd-instar larvae of Plutella xylostella and neonate of Chilo suppressalis. After transformation with modified cry1Ah1 genes into Var nippobare, the transgenic rice seedlings were detected by PCR, the positive rate containing target gene was more than 87%. Afterwards, the results of real-time RT-PCR and ELISA assay indicated that the highest expression level of five modified cry1Ah1 genes was that using the highest frequent codons. Average expression amount of Cry1Ah1 polypeptides was 0.104% of total soluble proteins from the positive transgenic rice.
Animals
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Bacillus thuringiensis
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genetics
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metabolism
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Bacterial Proteins
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biosynthesis
;
genetics
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Cloning, Molecular
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Codon
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genetics
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Endotoxins
;
biosynthesis
;
genetics
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Hemolysin Proteins
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biosynthesis
;
genetics
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Insecticides
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Lepidoptera
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Oryza
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genetics
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Pest Control, Biological
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methods
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Plants, Genetically Modified
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genetics
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Recombinant Proteins
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biosynthesis
;
genetics
7.Oxidative stress, biochemical and histopathological alterations in the liver and kidney of female rats exposed to low doses of deltamethrin (DM): a molecular assessment.
Issam CHARGUI ; Intissar GRISSA ; Fatma BENSASSI ; Mohamed Yahia HRIRA ; Samir HAOUEM ; Zohra HAOUAS ; Hassen BENCHEIKH
Biomedical and Environmental Sciences 2012;25(6):672-683
OBJECTIVETo evaluate histopathological alterations of the liver and kidney of female rats exposed to low doses of DM and its potential genotoxic activity.
METHODSFemale Wistar rats were randomly assigned to control (3 groups, 6 rats in each) and treatment groups (3 groups, 6 rats in each). They were subjected to subcutaneous injections of DM (at doses of 0.003, 0.03, and 0.3 mg/kg bw/d) after 30, 45, and 60 d, respectively.
RESULTSSignificant alterations were recorded in liver parenchyma induced by hepatic vacuolization, fragmented chromatin in nuclei, dilatation of sinusoids and congestions. Lesions within proximal and distal tubules were observed in the kidneys. Tissue congestions and severe alterations within glomeruli were visible. DM as a pyrethroid insecticide induced significant increase (P≤0.05) of plasma MDA concentrations after 45 d. A significant increase (P≤0.05) in plasma ALT (after 45 and 60 d) and AST (after 60 d) concentrations was recorded as compared to controls. During the whole experimental period the toxic agent provoked significant DNA damages (P≤0.05), especially in the dominance of classes 3 and 4 of obtained comet.
CONCLUSIONDM even at a very low dose displays harmful effects by disrupting hepatic and renal function and causing DNA damages in puberscent female rats. Low doses of DM are hepatotoxic and nephrotoxic.
Animals ; Aspartate Aminotransferases ; metabolism ; Behavior, Animal ; drug effects ; Chemical and Drug Induced Liver Injury ; metabolism ; pathology ; Creatinine ; blood ; Dose-Response Relationship, Drug ; Female ; Insecticides ; administration & dosage ; chemistry ; toxicity ; Kidney ; drug effects ; Kidney Diseases ; chemically induced ; pathology ; Liver ; drug effects ; Malondialdehyde ; Molecular Structure ; Nitriles ; administration & dosage ; chemistry ; toxicity ; Organ Size ; Oxidative Stress ; drug effects ; Pyrethrins ; administration & dosage ; chemistry ; toxicity ; Random Allocation ; Rats ; Urea ; blood ; Weight Gain ; drug effects
8.Larvicidal and irritant activities of hexane leaf extracts of Citrus sinensis against dengue vector Aedes aegypti L.
Radhika WARIKOO ; Ankita RAY ; Jasdeep Kaur SANDHU ; Roopa SAMAL ; Naim WAHAB ; Sarita KUMAR
Asian Pacific Journal of Tropical Biomedicine 2012;2(2):152-155
OBJECTIVETo assess the larvicidal and irritant activities of the hexane extracts of leaves of Citrus sinensis (C. sinensis) against the early fourth instars and female adults of Aedes aegypti (Ae. aegypti).
METHODSThe larvicidal potential of the prepared leaf extract was evaluated against early fourth instar larvae of Ae. aegypti using WHO protocol. The mortality counts were made after 24 h and LC50 and LC90 values were calculated. The efficacy of extract as mosquito irritant was assessed by contact irritancy assays. Extract-impregnated paper was placed on a glass plate over which a perspex funnel with a hole on the top was kept inverted. Single female adult, 3-day old unfed/blood-fed, was released inside the funnel. After 3 min of acclimatization time, the time taken for the first take-off and total number of flights undertaken during 15 min were scored.
RESULTSThe citrus leaf extracts from hexane possessed moderate larvicidal efficiency against dengue vector. The bioassays resulted in an LC50 and LC90 value of 446.84 and 1 370.96 ppm, respectively after 24 h of exposure. However, the extracts were proved to be remarkable irritant against adults Ae. aegypti, more pronounced effects being observed on blood-fed females than unfed females. The extract-impregnated paper was thus proved to be 7-11 times more irritable as compared with the control paper.
CONCLUSIONSThe hexane extracts from C. sinensis leaves are proved to be reasonably larvicidal but remarkably irritant against dengue vector. Further studies are needed to identify the possible role of extract as adulticide, oviposition deterrent and ovicidal agent. The isolation of active ingredient from the extract could help in formulating strategies for mosquito control.
Aedes ; drug effects ; Animals ; Citrus sinensis ; metabolism ; Dengue ; transmission ; Disease Vectors ; Female ; Insecticides ; pharmacology ; Larva ; drug effects ; Mosquito Control ; methods ; Plant Extracts ; pharmacology ; Plant Leaves ; metabolism
9.The assessment of hemoperfusion for the treatment of acute methamidophos poisoning.
Deng-Pan LAI ; Jian-Feng WANG ; Ju-Ping YAO ; Yi-Fen WANG ; Guo-Qin CHENG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2011;29(6):440-442
OBJECTIVETo explore the effect of hemoperfusion(HP) about the patients of methamidophos poisoning.
METHODSOn the basis of comprehensive treatment,15 cases of severe acute methamidophos poisoning patients were treated with HP, Blood samples were collected at 7 time points, before and 5, 15, 30, 45, 60mins following the beginning and the end of hemoperfusion. Blood samples were used for measuring the concentration of methamidophos and perfusion devices were used for measuring the volume of methamidophos adsorbed by the device after hemoperfusion.
RESULTS15 patients live in 12 cases, 3 cases of death. HP (former) blood Cholinesterase vigor were 662.60 + 632.05, HP (after) blood cholinesterase vigor were 2577.52 + 920.38 IU/L; The difference of blood Cholinesterase vigor between the before and after HP was statistically significant (P < 0.01). The patients' methamidophos concentration of blood when HP treated 45, 60, 120 min were respectively (851 + 672), (680 + 529), (587 + 520) microg /ml, there were significantly lower than that the patients' methamidophos concentration of blood who were before HP (1659 + 1105) microg/ml, a statistically significant difference (P < 0.01).
CONCLUSIONHP can be cut down obviously methamidophos poisoning patients serum concentrations of toxic, the experimental method directly prove the clinical application of carbon HP can really adsorption methamidophos.
Adult ; Cholinesterases ; metabolism ; Female ; Hemoperfusion ; methods ; Humans ; Insecticides ; poisoning ; Male ; Middle Aged ; Organothiophosphorus Compounds ; poisoning ; Treatment Outcome ; Young Adult
10.Production and identification of monoclonal antibodies against pesticide imidacloprid.
Gang LI ; Xianyong JI ; Guoliang QIAN ; Xiude HUA ; Na QIN ; Jie WANG ; Fengquan LIU
Chinese Journal of Biotechnology 2011;27(6):943-951
To produce high-affinity monoclonal antibodies against pesticide imidacloprid, we synthesized the haptens 1-[(6-Carboxylethylthio-3-pyridinyl) methyl] -N-nitro-imidazolidinimine (named as H1) and 1-[(6-Chloro-3-pyridinyl) methyl]-3-carboxylpropyl-N-nitro-2-imidazolidinimine (termed as H2). And then the haptens were coupled to bovine serum albumin (BSA) and ovalbumin (OVA) for immunogen (H1-BSA) and coating antigen (H2-OVA) respectively by NHS ester method. BALB/c mice were immunized with H1-BSA conjugate. We obtained two hybridoma cell lines 2F11/A9 and 2G6/G12 secreting antibody specific for imidacloprid from the conventional hybridoma technology. The result showed that the subtypes of obtained monoclonal antibodies were IgG3 and IgG1, respectively, and the titers of ascites were up to 1:128 000. The indirect competitive ELISA indicated the IC50 values of 5.3 and 28.3 ng/mL with detection limits of 1.1 ng/mL and 7.7 ng/mL, respectively. Two monoclonal antibodies had no apparent cross reactivity with six analogous compounds. Thus, two prepared monoclonal antibodies had a very high affinity and specificity, and it could be used to develop ELISA for rapid determination of imidacloprid residue and laid a solid foundation for research and development of products for immunoassay.
Animals
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Antibodies, Monoclonal
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biosynthesis
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Antibody Specificity
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Hybridomas
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metabolism
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Imidazoles
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immunology
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Insecticides
;
immunology
;
Mice
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Mice, Inbred BALB C
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Neonicotinoids
;
Nitro Compounds
;
immunology

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