Qiao C

References (11)

Title : A novel chlorpyrifos hydrolase CPD from Paracoccus sp. TRP: Molecular cloning, characterization and catalytic mechanism - Fan_2018_Electron.J.Biotechnol_31_10
Author(s) : Fan S , Li K , Yan Y , Wang J , Qiao C , Yang T , Jia Y , Zhao B
Ref : Electronic Journal of Biotechnology , 31 :10 , 2018
Abstract : Background: Biodegradation is a reliable approach for efficiently eliminating persistent pollutants such as chlorpyrifos. Despite many bacteria or fungi isolated from contaminated environment and capable of degrading chlorpyrifos, limited enzymes responsible for its degradation have been identified, let alone the catalytic mechanism of the enzymes. Results: In present study, the gene cpd encoding a chlorpyrifos hydrolase was cloned by analysis of genomic sequence of Paracoccus sp. TRP. Phylogenetic analysis and BLAST indicated that CPD was a novel member of organophosphate hydrolases. The purified CPD enzyme, with conserved catalytic triad (Ser155-Asp251-His281) and motif Gly-Asp-Ser-Ala-Gly, was significantly inhibited by PMSF, a serine modifier. Molecular docking between CPD and chlorpyrifos showed that Ser155 was adjacent to chlorpyrifos, which indicated that Ser155 may be the active amino acid involved in chlorpyrifos degradation. This speculation was confirmed by site-directed mutagenesis of Ser155Ala accounting for the decreased activity of CPD towards chlorpyrifos. According to the key role of Ser155 in chlorpyrifos degradation and molecular docking conformation, the nucleophilic catalytic mechanism for chlorpyrifos degradation by CPD was proposed. Conclusion: The novel enzyme CPD was capable of hydrolyze chlorpyrifos and Ser155 played key role during degradation of chlorpyrifos.
ESTHER : Fan_2018_Electron.J.Biotechnol_31_10
PubMedSearch : Fan_2018_Electron.J.Biotechnol_31_10
Gene_locus related to this paper: 9rhob-a0a1x7ll67

Title : Engineering Pseudomonas putida KT2440 for simultaneous degradation of organophosphates and pyrethroids and its application in bioremediation of soil - Zuo_2015_Biodegradation_26_223
Author(s) : Zuo Z , Gong T , Che Y , Liu R , Xu P , Jiang H , Qiao C , Song C , Yang C
Ref : Biodegradation , 26 :223 , 2015
Abstract : Agricultural soils are usually co-contaminated with organophosphate (OP) and pyrethroid pesticides. To develop a stable and marker-free Pseudomonas putida for co-expression of two pesticide-degrading enzymes, we constructed a suicide plasmid with expression cassettes containing a constitutive promoter J23119, an OP-degrading gene (mpd), a pyrethroid-hydrolyzing carboxylesterase gene (pytH) that utilizes the upp gene as a counter-selectable marker for upp-deficient P. putida. By introduction of suicide plasmid and two-step homologous recombination, both mpd and pytH genes were integrated into the chromosome of a robust soil bacterium P. putida KT2440 and no selection marker was left on chromosome. Functional expression of mpd and pytH in P. putida KT2440 was demonstrated by Western blot analysis and enzyme activity assays. Degradation experiments with liquid cultures showed that the mixed pesticides including methyl parathion, fenitrothion, chlorpyrifos, permethrin, fenpropathrin, and cypermethrin (0.2 mM each) were degraded completely within 48 h. The inoculation of engineered strain (10(6) cells/g) to soils treated with the above mixed pesticides resulted in a higher degradation rate than in noninoculated soils. All six pesticides could be degraded completely within 15 days in fumigated and nonfumigated soils with inoculation. Theses results highlight the potential of the engineered strain to be used for in situ bioremediation of soils co-contaminated with OP and pyrethroid pesticides.
ESTHER : Zuo_2015_Biodegradation_26_223
PubMedSearch : Zuo_2015_Biodegradation_26_223
PubMedID: 25917649

Title : Identification of resistant carboxylesterase alleles in Culex pipiens complex via PCR-RFLP - Zhang_2012_Parasit.Vectors_5_209
Author(s) : Zhang H , Meng F , Qiao C , Cui F
Ref : Parasit Vectors , 5 :209 , 2012
Abstract : BACKGROUND: Carboxylesterase overproduction is a frequently observed resistance mechanism of insects to organophosphate insecticides. As a major transmitter of human diseases, mosquitoes in the Culex pipiens complex have evolved 13 carboxylesterase alleles (Ester) that confer organophosphate resistance. Six alleles, Ester(B1), Ester(2), Ester(8), Ester(9), Ester(B10), and Ester(1)(1), have been observed in field populations in China, sometimes co-existing in one population. To differentiate the carboxylesterase alleles found in these field populations, PCR-RFLP was designed for use in resistance monitoring. RESULTS: Based on the DNA sequences of resistant and nonresistant carboxylesterase alleles, Ester B alleles were first amplified with PCR-specific primers and then digested with the restriction enzyme DraI. In this step, Ester(2) and Ester(1)(1) were differentiated from the other Ester alleles. When the other Ester B alleles were digested with the restriction enzyme XbaI, Ester(B1) and the susceptible C. p. pallens Ester were screened out. Ester(8) and Ester(9) were differentiated from Ester(B10) and the susceptible C. p. quinquefasciatus esterase allele, respectively, by amplifying and digesting the Ester A alleles with the restriction enzyme ApaLI. The effectiveness of the custom-designed PCR-RFLP was verified in two field mosquito populations. CONCLUSIONS: A PCR-RFLP based approach was developed to differentiate carboxylesterase alleles in Culex pipiens complex mosquitoes. These processes may be useful in monitoring the evolutionary dynamics of known carboxylesterase alleles as well as in the identification of new alleles in field populations.
ESTHER : Zhang_2012_Parasit.Vectors_5_209
PubMedSearch : Zhang_2012_Parasit.Vectors_5_209
PubMedID: 23006470
Gene_locus related to this paper: culpi-ESTA

Title : Transcriptomic and phylogenetic analysis of Culex pipiens quinquefasciatus for three detoxification gene families - Yan_2012_BMC.Genomics_13_609
Author(s) : Yan L , Yang P , Jiang F , Cui N , Ma E , Qiao C , Cui F
Ref : BMC Genomics , 13 :609 , 2012
Abstract : ABSTRACT BACKGROUND The genomes of three major mosquito vectors of human diseases Anopheles gambiae Aedes aegypti and Culex pipiens quinquefasciatus have been previously sequenced C p quinquefasciatus has the largest number of predicted protein-coding genes which partially results from the expansion of three detoxification gene families cytochrome P450 monooxygenases P450 glutathione S-transferases GST and carboxyl/cholinesterases CCE However unlike An gambiae and Ae aegypti which have large amounts of gene expression data C p quinquefasciatus has limited transcriptomic resources Knowledge of complete gene expression information is very important for the exploration of the functions of genes involved in specific biological processes In the present study the three detoxification gene families of C p quinquefasciatus were analyzed for phylogenetic classification and compared with those of three other dipteran insects Gene expression during various developmental stages and the differential expression responsible for parathion resistance were profiled using the digital gene expression DGE technique RESULTS A total of 302 detoxification genes were found in C p quinquefasciatus including 71 CCE 196 P450 and 35 cytosolic GST genes Compared with three other dipteran species gene expansion in Culex mainly occurred in the CCE and P450 families where the genes of alpha-esterases juvenile hormone esterases and CYP325 of the CYP4 subfamily showed the most pronounced expansion on the genome For the five DGE libraries 3.5-3.8 million raw tags were generated and mapped to 13314 reference genes Among 302 detoxification genes 225 75 were detected for expression in at least one DGE library One fourth of the CCE and P450 genes were detected uniquely in one stage indicating potential developmentally regulated expression A total of 1511 genes showed different expression levels between a parathion-resistant and a susceptible strain Fifteen detoxification genes including 2 CCEs 6 GSTs and 7 P450s were expressed at higher levels in the resistant strain CONCLUSIONS The results of the present study provide new insights into the functions and evolution of three detoxification gene families in mosquitoes and comprehensive transcriptomic resources for C p quinquefasciatus which will facilitate the elucidation of molecular mechanisms underlying the different biological characteristics of the three major mosquito vectors.
ESTHER : Yan_2012_BMC.Genomics_13_609
PubMedSearch : Yan_2012_BMC.Genomics_13_609
PubMedID: 23140097

Title : Two single mutations commonly cause qualitative change of nonspecific carboxylesterases in insects - Cui_2011_Insect.Biochem.Mol.Biol_41_1
Author(s) : Cui F , Lin Z , Wang H , Liu S , Chang H , Reeck G , Qiao C , Raymond M , Kang L
Ref : Insect Biochemistry & Molecular Biology , 41 :1 , 2011
Abstract : Carboxylesterases provide key mechanisms of resistance to insecticides, particularly organophosphates (OPs), in insects. One resistance mechanism is a qualitative change in the properties of a carboxylesterase. Two mutant forms, G151D and W271L, have been observed, mostly in dipteran species, to affect substrate specificity of enzymes. But whether these two single mutations can commonly change character of insect carboxylesterases is unknown. In our study carboxylesterase genes from seven insects distributed among four orders were cloned, mutated at position 151 or 271 and expressed in Escherichia coli. The kinetics of the purified recombinant proteins was examined towards an artificial carboxylester and two OP insecticides. The G/A151D and W271L mutation significantly reduced carboxylesterase activity in 87.5% and 100% cases, respectively, and at the same time conferred OP hydrolase activities in 62.5% and 87.5% cases, respectively. Thus, the change at position 271 is more effective to influence substrate specificity than that at position 151. These results may suggest that these two mutations have the potential to cause insecticide resistance broadly in insects.
ESTHER : Cui_2011_Insect.Biochem.Mol.Biol_41_1
PubMedSearch : Cui_2011_Insect.Biochem.Mol.Biol_41_1
PubMedID: 20888910
Gene_locus related to this paper: aphgo-cxest

Title : Correlation between carboxylesterase alleles and insecticide resistance in Culex pipiens complex from China - Liu_2011_Parasit.Vectors_4_236
Author(s) : Liu Y , Zhang H , Qiao C , Lu X , Cui F
Ref : Parasit Vectors , 4 :236 , 2011
Abstract : BACKGROUND: In China, large amounts of chemical insecticides are applied in fields or indoors every year, directly or indirectly bringing selection pressure on vector mosquitoes. Culex pipiens complex has evolved to be resistant to all types of chemical insecticides, especially organophosphates, through carboxylesterases. Six resistant carboxylesterase alleles (Ester) were recorded previously and sometimes co-existed in one field population, representing a complex situation for the evolution of Ester genes. RESULTS: In order to explore the evolutionary scenario, we analyzed the data from an historical record in 2003 and a recent investigation on five Culex pipiens pallens populations sampled from north China in 2010. Insecticide bioassays showed that these five populations had high resistance to pyrethroids, medium resistance to organophosphates, and low resistance to carbamates. Six types of Ester alleles, EsterB1, Ester2, Ester8, Ester9, EsterB10, and Ester11 were identified, and the overall pattern of their frequencies in geographic distribution was consistent with the report seven years prior to this study. Statistical correlation analysis indicated that Ester8 and Ester9 positively correlated with resistance to four insecticides, and EsterB10 to one insecticide. The occurrences of these three alleles were positively correlated, while the occurrence of EsterB1 was negatively correlated with Ester8, indicating an allelic competition. CONCLUSION: Our analysis suggests that one insecticide can select multiple Ester alleles and one Ester allele can work on multiple insecticides. The evolutionary scenario of carboxylesterases under insecticide selection is possibly "one to many".
ESTHER : Liu_2011_Parasit.Vectors_4_236
PubMedSearch : Liu_2011_Parasit.Vectors_4_236
PubMedID: 22177233

Title : Dynamics of esterase alleles in Culex pipiens complex mosquitoes in Beijing - Yan_2008_J.Econ.Entomol_101_1897
Author(s) : Yan S , Wu Z , Cui F , Zhao Q , Qiao C
Ref : J Econ Entomol , 101 :1897 , 2008
Abstract : To investigate insecticide resistance levels and dynamic changes of carboxylesterase polymorphism with time in resistant populations of mosquitoes in the Culex pipiens complex, four field populations were collected in September 2006. The resistance levels of fourth-instar larvae to organophosphate (dichlorvos, parathion, and chlorpyrifos), carbamate (fenobucarb and propoxur), and pyrethroid (permethrin and tetramethrin) insecticides were determined by bioassay. Larvae had a low but significant resistance to organophosphate and carbamate insecticides but no significant resistance to pyrethroid insecticides. Starch gel electrophoresis revealed the presence of the overproduced esterases B1, A2-B2, A8-B8, A9-B9, and All-B11. The frequency of each overproduced esterases varied depending on its regional localities. Compared with previous surveys, the polymorphism of amplified esterase alleles in Beijing populations increased, although the resistance level to organophosphate insecticides declined.
ESTHER : Yan_2008_J.Econ.Entomol_101_1897
PubMedSearch : Yan_2008_J.Econ.Entomol_101_1897
PubMedID: 19133472

Title : Different amino-acid substitutions confer insecticide resistance through acetylcholinesterase 1 insensitivity in Culex vishnui and Culex tritaeniorhynchus (Diptera: Culicidae) from China - Alout_2007_J.Med.Entomol_44_463
Author(s) : Alout H , Berthomieu A , Cui F , Tan Y , Berticat C , Qiao C , Weill M
Ref : Journal of Medical Entomology , 44 :463 , 2007
Abstract : Insecticide resistance owing to insensitive acetylcholinesterase (AChE)1 has been reported in several mosquito species, and only two mutations in the ace-1 gene have been implicated in resistance: 119S and 331W substitutions. We analyzed the AChE1 resistance status of Culex vishnui (Theobald) and Culex tritaeniorhynchus Giles sampled in various regions of China. These two species displayed distinct mutations leading to AChE1 insensitivity; the 119S substitution in resistant C. vishnui mosquitoes and the 331W substitution in resistant C. tritaeniorhynchus. A biochemical test was validated to detect the 331W mutation in field samples. The comparison of the recombinant G119S and 331W mutant proteins produced in vitro with the AChE1 extracted from resistant mosquitoes indicated that the AChE1 insensitivity observed could be specifically attributed to these substitutions. Comparison of their biochemical characteristics indicated that the resistance conferred by these mutations depends on the insecticide used, regardless of its class. This resistance seemed to be fixed in the Cx. tritaeniorhynchus populations sampled in a 2000-km transect, suggesting a very high level of insecticide application or a low fitness cost associated with this 331W mutation.
ESTHER : Alout_2007_J.Med.Entomol_44_463
PubMedSearch : Alout_2007_J.Med.Entomol_44_463
PubMedID: 17547232
Gene_locus related to this paper: culpi-ACHE1

Title : Bioremediation of organophosphorus pesticides by surface-expressed carboxylesterase from mosquito on Escherichia coli - Zhang_2004_Biotechnol.Prog_20_1567
Author(s) : Zhang J , Lan W , Qiao C , Jiang H , Mulchandani A , Chen W
Ref : Biotechnol Prog , 20 :1567 , 2004
Abstract : The insecticide resistance-associated esterase, carboxylesterase B1 (CaE B1), from mosquito was used to degrade the organophosphorus compounds. To eradicate the need for enzyme purification and minimize the resistance to mass transport of the substrate and product across the cell membranes, the CaE B1 was displayed on the cell surface of Escherichia coli fused to the C-terminus of the ice nucleation protein (INP). The presence of CaE B1 on the bacterial cell surface was verified by SDS-PAGE, Western blotting analysis, and immunofluorescence microscopy. More than 50% of active CaE B1 is exported across the membrane and anchored onto the cell surface as determined by proteinase accessibility and cell fractionation experiments. In contrast, only a 6% drop in activity for proteinase K-treated cells was detected from E.coli cells containing pET-B1. From the degradation experiment, more than 80% of the malathion was degraded by whole cells containing plasmid pUC-NC-B1. Constitutive expression of CaE B1 on the surface using INPNC resulted in no cell lysis, and the suspended cultures also exhibited good stability. Because of their high biodegradation activity and superior stability, these "live biocatalysts" are promising for detoxification of organophosphorus pesticides.
ESTHER : Zhang_2004_Biotechnol.Prog_20_1567
PubMedSearch : Zhang_2004_Biotechnol.Prog_20_1567
PubMedID: 15458345

Title : Automated programming of degenerate primers and the cloning of the diamondback esterase gene - Huang_2002_Kun.Chong.Zhi.Shi_39_458
Author(s) : Huang J , Wang S , Qiao C
Ref : Kun Chong Zhi Shi , 39 :458\ , 2002
Abstract : It is a normal strategy to clone protein family cDNA using the degeneracy of the code to design PCR primers from protein multiple-sequence alignments. With the tools of blastp, blockmaker, CodeHop, SwissProt, and SpTrEMBL, degenerate primers were designed for cloning of the insect esterase cDNA. Using one pair of primers, a partial cDNA was obtained from the diamondback moth by RT-PCR. Similarity alignment showed that the products of the cloned cDNA were very similar to those of insect esterases. The results indicated that these degenerate primers designed bhy this software could be used to obtaining specific RT-PCR product.
ESTHER : Huang_2002_Kun.Chong.Zhi.Shi_39_458
PubMedSearch : Huang_2002_Kun.Chong.Zhi.Shi_39_458

Title : Characterization of the acetylcholinesterase gene from insecticide-resistant houseflies (Musca domestica) - Huang_1997_Chin.J.Biotechnol_13_177
Author(s) : Huang Y , Qiao C , Williamson MS , Devonshire AL
Ref : Chin J Biotechnol , 13 :177 , 1997
Abstract : Acetylcholinesterase (AChE) is the target site for the organophosphates and carbamates in insects. Widespread use of these two classes of insecticides has led to the selection of resistance. Target modification was regarded as a molecular mechanism in some resistance species. The altered AChEs with reduced sensitivity to inhibition are related to this resistance. AChE genes from two insecticide-resistant housefly (Musca domestica) strains D3 and Kash were isolated and sequenced using RT-PCR and streptavidin-linked magnetic bead techniques. The cDNAs have a 2082-bp open reading frame from which the complete amino acid sequence of AChE has been deduced. Some differences in nucleotide sequence and four-point mutations of amino acid were found compared to a susceptible strain, i.e., the Cooper strain. Three substitutions are likely to confer insecticide insensitivity, which seems that D3 and Kash belong to CH2 pattern of resistance.
ESTHER : Huang_1997_Chin.J.Biotechnol_13_177
PubMedSearch : Huang_1997_Chin.J.Biotechnol_13_177
PubMedID: 9429779
Gene_locus related to this paper: musdo-ACHE