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Journal of Agricultural and Food... Dec 2023The black cutworm is a serious crop pest. Phoxim, an organophosphorus insecticide, has been widely used to control . When phoxim is extensively applied, the...
The black cutworm is a serious crop pest. Phoxim, an organophosphorus insecticide, has been widely used to control . When phoxim is extensively applied, the susceptibility of to insecticide is reduced. However, the mechanisms of tolerance of to phoxim remain unclear. Herein, we report that an epsilon class glutathione -transferase, AiGSTE1, confers phoxim tolerance in . Exposure to a sublethal concentration (LC) of phoxim caused oxidative stress and activated the transcription of genes in larvae. Recombinant AiGSTE1 expressed in could metabolize phoxim. Furthermore, cells overexpressing AiGSTE1 displayed significant tolerance to oxidative stress. Knockdown of by RNA interference significantly increased the mortality of larvae to phoxim. These results demonstrate that AiGSTE1 confers phoxim tolerance in by metabolizing the insecticide and preventing phoxim-induced oxidative stress.
Topics: Animals; Lepidoptera; Insecticides; Escherichia coli; Organophosphorus Compounds; Moths; Larva
PubMed: 38088263
DOI: 10.1021/acs.jafc.3c07964 -
Molecules (Basel, Switzerland) Nov 2019Phoxim, a type of organophosphorus pesticide (OP), is widely used in both agriculture and fisheries. The persistence of phoxim has caused serious environmental pollution...
Phoxim, a type of organophosphorus pesticide (OP), is widely used in both agriculture and fisheries. The persistence of phoxim has caused serious environmental pollution problems. In this study, YP6 (YP6), which is capable of promoting plant growth and degrading broad-spectrum OPs, was used to study phoxim degradation. Different culture media were applied to evaluate the growth and phoxim degradation of YP6. YP6 can grow rapidly and degrade phoxim efficiently in Luria-Bertani broth (LB broth) medium. Furthermore, it can also utilize phoxim as the sole phosphorus source in a mineral salt medium. Response surface methodology was performed to optimize the degradation conditions of phoxim by YP6 in LB broth medium. The optimum biodegradation conditions were 40 °C, pH 7.20, and an inoculum size of 4.17% (/). The phoxim metabolites, ,-diethylthiophosphoric ester, phoxom, and α-cyanobenzylideneaminooxy phosphonic acid, were confirmed by liquid chromatography-mass spectrometry. Meanwhile, transcriptome analysis and qRT-PCR were performed to give insight into the phoxim-stress response at the transcriptome level. The hydrolase-, oxidase-, and NADPH-cytochrome P450 reductase-encoding genes were significantly upregulated for phoxim hydrolysis, sulfoxidation, and o-dealkylation. Furthermore, the phoxim biodegradation pathways by YP6 were proposed, for the first time, based on transcriptomic data and product analysis.
Topics: Bacillus amyloliquefaciens; Biodegradation, Environmental; Genes, Bacterial; Hydrogen-Ion Concentration; Hydrolysis; NADPH-Ferrihemoprotein Reductase; Organothiophosphorus Compounds; Pesticides; Transcriptome
PubMed: 31694203
DOI: 10.3390/molecules24213997 -
Pesticide Biochemistry and Physiology Jan 2022The poultry red mite, Dermanyssus gallinae, is the most important blood sucking ectoparasite of egg laying hens and causes economic losses in poultry farms worldwide....
The poultry red mite, Dermanyssus gallinae, is the most important blood sucking ectoparasite of egg laying hens and causes economic losses in poultry farms worldwide. Although various management methods exist, the control of poultry red mites (PRMs) mainly relies on acaricides such as pyrethroids and organophosphates (OPs) in many regions of the world. However, repeated use of these synthetic chemicals has resulted in resistance development causing control failure of PRM. In this study, we investigated acaricide resistance mechanisms of Turkish PRM populations. First, we obtained the COI sequence from 30 PRM populations from different regions in Turkey and identified four different COI haplotypes. Toxicity assays showed that four field-collected PRM populations were highly resistant to the pyrethroid alpha-cypermethrin, with resistance ratios (RRs) varying between 100- and 400-fold, while two of these populations had a RR of more than 24-fold against the OP acaricide phoxim. Biochemical assays showed a relatively higher activity of glutathione-S-transferases and carboxyl-cholinesterases, two well-known classes of detoxification enzymes, in one of these resistant populations. In addition, we also screened for mutations in the gene encoding the voltage-gated sodium channel (vgsc) and acetylcholinesterase 1 (ace-1), the target-site of pyrethroids and OPs, respectively. In all but two PRM populations, at least one vgsc mutation was detected. A total of four target-site mutations, previously associated with pyrethroid resistance, M918T, T929I, F1534L, F1538L were found in domain II and III of the VGSC. The T929I mutation was present in the vgsc of almost all PRM populations, while the other mutations were only found at low frequency. The G119S/A mutation in ace-1, previously associated with OP resistance, was found in PRM for the first time and present in fourteen populations. Last, both alive and dead PRMs were genotyped after pesticide exposure and supported the possible role of target-site mutations, T929I and G119S, in alpha-cypermethrin and phoxim resistance, respectively. To conclude, our study provides a current overview of resistance levels and resistance mutations in Turkish PRM populations and might aid in the design of an effective resistance management program of PRM in Turkey.
Topics: Acaricides; Acetylcholinesterase; Animals; Chickens; Mites; Turkey
PubMed: 34955178
DOI: 10.1016/j.pestbp.2021.104985 -
Pest Management Science Apr 2021Carboxylesterases (CarEs) are associated with detoxification of xenobiotics, including insecticides, in organism bodies. Overexpression of CarE genes is considered to...
BACKGROUND
Carboxylesterases (CarEs) are associated with detoxification of xenobiotics, including insecticides, in organism bodies. Overexpression of CarE genes is considered to have an important role in insecticide resistance in insects, however its involvement in multi-insecticide resistance has rarely been reported. This study aimed to assess the function of a CarE gene (PxαE8) in resistance to five insecticides in Plutella xylostella.
RESULTS
Relative expression of PxαE8 in three multi-insecticide-resistant Plutella xylostella populations, GD-2017, GD-2019 and HN, was14.8-, 19.5- and 28.0-fold higher than that in the susceptible population. Exposure to lethal concentrations associated with 25% mortality (LC ) of beta-cypermethrin, chlorantraniliprole, metaflumizone, phoxim and tebufenozide could induce the specific activity of CarEs and increase the relative expression of PxαE8. By contrast, knockdown of PxαE8 expression dramatically reduced the activity of CarEs and increased the resistance of P. xylostella (GD-2019) larvae to beta-cypermethrin and phoxim by 47.4% and 45.5%, respectively. Further, a transgenic line of Drosophila melanogaster overexpressing PxαE8 was constructed and the bioassay results showed that the tolerance of transgenic Drosophila to beta-cypermethrin and phoxim was 3.93- and 3.98-fold higher than that of the untransgenic line.
CONCLUSION
These results provide evidence that overexpression of PxαE8 is involved in resistance, at least to beta-cypermethrin and phoxim, in multi-insecticide-resistant P. xylostella populations, which could help in further understanding the molecular mechanisms of multi-insecticide resistance in this pest. © 2020 Society of Chemical Industry.
Topics: Animals; Carboxylesterase; Carboxylic Ester Hydrolases; Drosophila melanogaster; Insecticide Resistance; Insecticides; Larva; Moths; Organothiophosphorus Compounds; Pyrethrins
PubMed: 33342080
DOI: 10.1002/ps.6238 -
Fish & Shellfish Immunology Oct 2020Due to overuse and terrestrial input, there are large quantities of phoxim and prometryne residues in some aquatic environments. In the present study, the effects of...
Due to overuse and terrestrial input, there are large quantities of phoxim and prometryne residues in some aquatic environments. In the present study, the effects of these compounds on Penaeus vannamei hepatopancreas were analysed at the transcriptome level to investigate toxicity in this nontarget aquaculture organism. Twelve normalised cDNA libraries were constructed using RNA from phoxim and prometryne treatment groups, and an untreated control group. A total of 667,750,902 clean reads were obtained. Analysis of differentially expressed genes (DEGs) identified 449 in control vs phoxim groups, 185 in control vs prometryne groups, and 183 in prometryne vs phoxim groups. In the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, arachidonic acid metabolism, pancreatic secretion, linoleic acid metabolism, and beta-alanine metabolism pathways were significantly enriched in control vs phoxim groups. In control vs prometryne groups, lysosome, pentose and glucuronate interconversion, antigen processing and presentation, and glycosaminoglycan degradation pathways were significantly enriched. In prometryne vs phoxim groups, protein digestion and absorption, extracellular matrix (ECM)-receptor interaction, PI3K-Akt signalling, cell adhesion molecule (CAM), AGE-RAGE signalling related to diabetic complications, focal adhesion, and renin secretion pathways were significantly enriched. In further detailed analysis, glutathione S-transferase (GST), glutathione peroxidase and basic phospholipase A2 were downregulated in the phoxim treatment group, indicating that phoxim damaged hepatopancreas. Upregulation of phospholipase A2 (secretory phospholipase A2-like) indicates possible inflammatory pathological injury to hepatopancreas caused by phoxim. Meanwhile, downregulation of CD63 indicates that prometryne affect the immune system.
Topics: Animals; Gene Expression Profiling; Hepatopancreas; Herbicides; Insecticides; Organothiophosphorus Compounds; Penaeidae; Prometryne; Random Allocation; Transcriptome; Water Pollutants, Chemical
PubMed: 32702478
DOI: 10.1016/j.fsi.2020.07.037 -
Archives of Insect Biochemistry and... Nov 2021Glyphodes pyloalis Walker has become one of the most significant mulberry pests, and it has caused serious economic losses in major mulberry growing regions in China....
Glyphodes pyloalis Walker has become one of the most significant mulberry pests, and it has caused serious economic losses in major mulberry growing regions in China. Peptidoglycan recognition proteins (PGRPs) are responsible for initiating and regulating immune signalling pathways in insects. However, their roles responding to chemical pesticides is still less known. This study aimed to investigate the possible detoxication function of GpPGRP-S2 and GpPGRP-S3 in G. pyloalis in response to chlorfenapyr and phoxim. The chlorfenapyr and phoxim treatment significantly induced the expression level of GpPGRP-S3 at 48 h. In addition, the expression levels of GpPGRP-S2 and GpPGRP-S3 in the chlorfenapyr/phoxim treatment group were significantly higher in midgut than those in the control group at 48 h. The results of the survival experiment showed that silencing either GpPGRP-S2 or GpPGRP-S3 would not influence the survival rate of G. pyloalis which treated with phoxim, however, silencing GpPGRP-S2 or GpPGRP-S3 would cause G. pyloalis to be more easily killed by chlorfenapyr. The expression of carboxylesterase GpCXE1 was significantly induced by chlorfenapyr/phoxim treatment, while it was suppressed once silenced GpPGRP-S2 followed with chlorfenapyr treatment or silenced GpPGRP-S3 followed with phoxim treatment. These results might suggest that under the chlorfenapyr/phoxim treatment condition, the connection between GpPGRPs and detoxification genes in insect was induced to maintain physiological homeostasis; and these results may further enrich the mechanisms of insects challenged by insecticides.
Topics: Animals; Carrier Proteins; Insecticides; Moths; Organothiophosphorus Compounds; Pest Control; Pyrethrins
PubMed: 34499777
DOI: 10.1002/arch.21842 -
Analytical Methods : Advancing Methods... Feb 2022Herein, an ionic-liquid-based effervescence-enhanced magnetic solid-phase extraction (ILE-MSPE) approach for the extraction/concentration of organophosphorus pesticides...
Herein, an ionic-liquid-based effervescence-enhanced magnetic solid-phase extraction (ILE-MSPE) approach for the extraction/concentration of organophosphorus pesticides in waters is reported with high stability and portability for rapid sample pretreatment in the field. The ionic-liquid-based magnetic effervescent tablet, composed of magnetic nanoparticles (FeO), sodium carbonate (NaCO) as an alkaline source, and an ionic liquid ([CMIM][PF]), played triple functions: extractant, dispersant, and retrieving agent. Based on the one-factor-at-a-time method, the important variables for the ILE-MSPE approach were optimized as follows: as an extractant, 70 μL of [CMIM][PF]; molar ratio of alkaline to acidic sources (NaCO : HCHO) as 1 : 1; and mass of magnetic nanoparticles (MNPs) of 30 mg. By integrating HPLC-DAD detection, the ILE-MSPE approach offered the limits of detection of 0.14-0.22 μg L and fortified recoveries of 81.4-97.6% for three representative species (methamidophos, phoxim, and parathion) in water samples. The relative standard deviations were lower than 4.9% for both the intra-day and inter-day precision. Overall, the newly developed method is environmentally benign, time-saving, and feasible for outdoor application.
Topics: Ionic Liquids; Magnetic Phenomena; Organophosphorus Compounds; Pesticides; Solid Phase Extraction; Water
PubMed: 35084403
DOI: 10.1039/d1ay01698a -
Ecotoxicology and Environmental Safety Mar 2024Nanopolystyrene (NP) and phoxim (PHO) are common environmental pollutants in aquatic systems. We evaluated the toxic effects of exposure to ambient concentrations of NP...
Exposure to nanopolystyrene and phoxim at ambient concentrations causes oxidative stress and inflammation in the intestines of the Chinese mitten crab (Eriocheir sinensis).
Nanopolystyrene (NP) and phoxim (PHO) are common environmental pollutants in aquatic systems. We evaluated the toxic effects of exposure to ambient concentrations of NP and/or PHO in the intestines of the Chinese mitten crab (Eriocheir sinensis). Our study showed that histopathological changes were observed in the intestines. Specifically, NP and/or PHO exposure increased intraepithelial lymphocytes. Furthermore, NP and/or PHO exposure induced oxidative stress, as evidenced by a significant decrease in superoxide dismutase activity (SOD), peroxidase activity (POD), and total antioxidant capacity (T-AOC). Pro-inflammatory gene expression and transcriptome analysis demonstrated that NP and/or PHO exposure induced the intestinal inflammatory response. Transcriptome results showed that NP and/or PHO exposure upregulated the NF-κB signaling pathway, which is considered a key pathway in the inflammatory response. Additionally, the expression of pro-inflammatory genes significantly increased after a single exposure to NP or PHO, but it exhibited a significant decrease after the co-exposure. The downregulation of these genes in the co-exposure group likely suggested that the co-exposure mitigated intestinal inflammation response in E. sinensis. Collectively, our findings mainly showed that NP and/or PHO exposure at ambient concentrations induces oxidative stress and inflammatory response in the intestines of E. sinensis.
Topics: Animals; Oxidative Stress; Antioxidants; Intestines; Inflammation; Brachyura; Organothiophosphorus Compounds
PubMed: 38387141
DOI: 10.1016/j.ecoenv.2024.116126 -
Analytical Chemistry Feb 2022A novel high-throughput aptamer microarray fluorescent method based on thioflavin T (ThT) was established for the sensitive detection of phoxim, parathion,...
A novel high-throughput aptamer microarray fluorescent method based on thioflavin T (ThT) was established for the sensitive detection of phoxim, parathion, fensulfothion, and isocarbophos. In this work, the aptamers in binding buffer tended to have the antiparallel G-quadruplex structure, which can bind ThT and release its potential fluorescence signal. However, when the organophosphorus pesticides (OPs) were present, partial aptamers preferred to bind them, forcing the displacement of ThT from the G-quadruplex and resulting in the significant decrease in fluorescence signal. Under optimal experimental conditions (12T spacer, 300 nM aptamer, and 80 μM ThT), the OP aptamer microarray has low limits of detection of 25.4 ng/mL for phoxim, 12.0 ng/mL for parathion, 7.7 ng/mL for fensulfothion, and 9.9 ng/mL for isocarbophos. The accuracy and reliability of the method is further verified by testing the recovery rate of OPs spiked in two different complicated sample matrices (pears and radishes). It is worth mentioning that not only the developed aptamer microarray technology has low sensitivity and a broad spectrum, but it also allows for high-throughput and rapid analysis of a variety OPs, which overcomes some of the shortcomings of other OP detection methods.
Topics: Aptamers, Nucleotide; Biosensing Techniques; Fluorescent Dyes; Organophosphorus Compounds; Pesticides; Reproducibility of Results; Spectrometry, Fluorescence
PubMed: 35133802
DOI: 10.1021/acs.analchem.1c04650 -
Journal of Agricultural and Food... Jan 2021Insect resistance to insecticides is an increasingly serious problem, and the resistant mechanisms are complicated. The resistance research based on the chemosensory...
Insect resistance to insecticides is an increasingly serious problem, and the resistant mechanisms are complicated. The resistance research based on the chemosensory pathway is one of the hot problems at present, but the specific binding mechanism of chemosensory genes and insecticides remains elusive. The binding mechanism of GOBP2 (belong to insect chemosensory gene) with two insecticides was investigated by computational and experimental approaches. Our calculation results indicated that four key residues (Phe12, Ile52, Ile94, and Phe118) could steadily interact with these two insecticides and be assigned as hotspot sites responsible for their binding affinities. The significant alkyl-π and hydrophobic interactions involved by these four hotspot residues were found to be the driving forces for their binding affinities, especially for two residues (Phe12 and Ile94) that significantly contribute to the binding of chlorpyrifos, which were also validated by our binding assay results. Furthermore, we also found that the GOBP2-chlorpyrifos/phoxim complexes can be more efficiently converged in the residue-specific force field-(RSFF2C) and its higher accuracy and repeatability in protein dynamics simulation, per-residue free energy decomposition, and computational alanine scanning calculations have also been achieved in this paper. These findings provided useful insights for efficient and reliable calculation of the binding mechanism of relevant GOBPs with other insecticides, facilitating to develop new and efficient insecticides targeting the key sites of GOBP2.
Topics: Animals; Chlorpyrifos; Insect Proteins; Molecular Dynamics Simulation; Moths; Organothiophosphorus Compounds; Protein Binding; Receptors, Odorant
PubMed: 33356208
DOI: 10.1021/acs.jafc.0c05389