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Parasites & Vectors Jun 2015Glutathione S-transferases (GSTs) facilitate detoxification of drugs by catalysing the conjugation of the reduced glutathione (GSH) to electrophilic xenobiotic...
BACKGROUND
Glutathione S-transferases (GSTs) facilitate detoxification of drugs by catalysing the conjugation of the reduced glutathione (GSH) to electrophilic xenobiotic substrates and therefore have a function in multi-drug resistance. As a result, knowledge of GSTs can inform both drug resistance in, and novel interventions for, the control of endo- and ectoparasite species. Acaricide resistance and the need for novel control methods are both pressing needs for Dermanyssus gallinae, a highly economically important haematophagous ectoparasite of poultry.
METHODS
A transcriptomic database representing D. gallinae was examined and 11 contig sequences were identified with GST BlastX identities. The transcripts represented by 3 contigs, designated Deg-GST-1, -2 and -3, were fully sequenced and further characterized by phylogenetic analysis. Recombinant versions of Deg-GST-1, -2 and -3 (rDeg-GST) were enzymically active and acaricide-binding properties of the rDeg-GSTs were established by evaluating the ability of selected acaricides to inhibit the enzymatic activity of rDeg-GSTs.
RESULTS
6 of the identified GSTs belonged to the mu class, followed by 3 kappa, 1 omega and 1 delta class molecules. Deg-GST-1 and -3 clearly partitioned with orthologous mu class GSTs and Deg-GST-2 partitioned with delta class GSTs. Phoxim, permethrin and abamectin significantly inhibited rDeg-GST-1 activity by 56, 35 and 17% respectively. Phoxim also inhibited rDeg-2-GST (14.8%) and rDeg-GST-3 (20.6%) activities.
CONCLUSIONS
Deg-GSTs may have important roles in the detoxification of pesticides and, with the increased occurrence of acaricide resistance in this species worldwide, Deg-GSTs are attractive targets for novel interventions.
Topics: Acaricides; Amino Acid Sequence; Animals; Databases, Factual; Drug Resistance; Gene Expression Regulation, Enzymologic; Glutathione Transferase; Mites; Molecular Sequence Data; Phylogeny; Transcriptome
PubMed: 26112960
DOI: 10.1186/s13071-015-0960-9 -
Journal of Analytical Methods in... 2015An efficient, rapid, and selective method for sample pretreatment, namely, molecularly imprinted matrix solid-phase dispersion (MI-MSPD) coupled with gas chromatography...
Molecularly imprinted nanomicrospheres as matrix solid-phase dispersant combined with gas chromatography for determination of four phosphorothioate pesticides in carrot and yacon.
An efficient, rapid, and selective method for sample pretreatment, namely, molecularly imprinted matrix solid-phase dispersion (MI-MSPD) coupled with gas chromatography (GC), was developed for the rapid isolation of four phosphorothioate organophosphorus pesticides (tolclofos-methyl, phoxim, chlorpyrifos, and parathion-methyl) from carrot and yacon samples. New molecularly imprinted polymer nanomicrospheres were synthesized by using typical structural analogue tolclofos-methyl as a dummy template via surface grafting polymerization on nanosilica. Then, these four pesticides in carrot and yacon were extracted and adsorbed using the imprinted nanomicrospheres and further determined by gas chromatography. Under the optimized conditions, a good linearity of four pesticides was obtained in a range of 0.05-17.0 ng·g(-1) with R varying from 0.9971 to 0.9996, and the detection limit of the method was 0.012~0.026 ng·g(-1) in carrot and yacon samples. The recovery rates at two spiked levels were in the range of 85.4-105.6% with RSD ≤9.6%. The presented MI-MSPD method combined the advantages of MSPD for allowing the extraction, dispersion, and homogenization in two steps and the advantages of MIPs for high affinity and selectivity towards four phosphorothioate pesticides, which could be applied to the determination of pesticide residues in complicated vegetal samples.
PubMed: 25954569
DOI: 10.1155/2015/385167 -
Journal of Hazardous Materials Oct 2015Organophosphorus insecticides have been widely used, which are highly poisonous and cause serious concerns over food safety and environmental pollution. A bacterial...
Organophosphorus insecticides have been widely used, which are highly poisonous and cause serious concerns over food safety and environmental pollution. A bacterial strain being capable of degrading O,O-dialkyl phosphorothioate and O,O-dialkyl phosphate insecticides, designated as G1, was isolated from sludge collected at the drain outlet of a chlorpyrifos manufacture plant. Physiological and biochemical characteristics and 16S rDNA gene sequence analysis suggested that strain G1 belongs to the genus Stenotrophomonas. At an initial concentration of 50 mg/L, strain G1 degraded 100% of methyl parathion, methyl paraoxon, diazinon, and phoxim, 95% of parathion, 63% of chlorpyrifos, 38% of profenofos, and 34% of triazophos in 24 h. Orthogonal experiments showed that the optimum conditions were an inoculum volume of 20% (v/v), a substrate concentration of 50 mg/L, and an incubation temperature in 40 °C. p-Nitrophenol was detected as the metabolite of methyl parathion, for which intracellular methyl parathion hydrolase was responsible. Strain G1 can efficiently degrade eight organophosphorus pesticides (OPs) and is a very excellent candidate for applications in OP pollution remediation.
Topics: Biodegradation, Environmental; Organophosphorus Compounds; Pesticides; RNA, Ribosomal, 16S; Sewage; Stenotrophomonas; Water Pollutants, Chemical
PubMed: 25938642
DOI: 10.1016/j.jhazmat.2015.04.052 -
Cell Stress & Chaperones Jan 2015Arginine kinases (AK) in invertebrates play the same role as creatine kinases in vertebrates. Both proteins are important for energy metabolism, and previous studies on...
Arginine kinases (AK) in invertebrates play the same role as creatine kinases in vertebrates. Both proteins are important for energy metabolism, and previous studies on AK focused on this attribute. In this study, the arginine kinase gene was isolated from Apis cerana cerana and was named AccAK. A 5'-flanking region was also cloned and shown to contain abundant putative binding sites for transcription factors related to development and response to adverse stress. We imitated several abiotic and biotic stresses suffered by A. cerana cerana during their life, including heavy metals, pesticides, herbicides, heat, cold, oxidants, antioxidants, ecdysone, and Ascosphaera apis and then studied the expression patterns of AccAK after these treatments. AccAK was upregulated under all conditions, and, in some conditions, this response was very pronounced. Western blot and AccAK enzyme activity assays confirmed the results. In addition, a disc diffusion assay showed that overexpression of AccAK reduced the resistance of Escherichia coli cells to multiple adverse stresses. Taken together, our results indicated that AccAK may be involved of great significance in response to adverse abiotic and biotic stresses.
Topics: 5' Flanking Region; Amino Acid Sequence; Animals; Arginine Kinase; Base Sequence; Bees; Binding Sites; Escherichia coli; Herbicides; Metals, Heavy; Molecular Sequence Data; Organothiophosphorus Compounds; Pesticides; Phylogeny; Sequence Alignment; Stress, Physiological; Temperature; Transcription Factors; Transcriptome; Up-Regulation
PubMed: 25135575
DOI: 10.1007/s12192-014-0535-2