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Zhongli Cui - One of the best experts on this subject based on the ideXlab platform.

  • involvement of the cytochrome p450 system ethbad in the n deethoxymethylation of Acetochlor by rhodococcus sp strain t3 1
    Applied and Environmental Microbiology, 2015
    Co-Authors: Fei Wang, Ying Hou, Weiliang Dong, Jie Zhou, Yan Huang, Zhongli Cui
    Abstract:

    Acetochlor [2-chloro-N-(ethoxymethyl)-N-(2-ethyl-6-methylphenyl)-acetamide] is a widely applied herbicide with potential carcinogenic properties. N-Deethoxymethylation is the key step in Acetochlor biodegradation. N-Deethoxymethylase is a multicomponent enzyme that catalyzes the conversion of Acetochlor to 2′-methyl-6′-ethyl-2-chloroacetanilide (CMEPA). Fast detection of CMEPA by a two-enzyme (N-deethoxymethylase–amide hydrolase) system was established in this research. Based on the fast detection method, a three-component enzyme was purified from Rhodococcus sp. strain T3-1 using ammonium sulfate precipitation and hydrophobic interaction chromatography. The molecular masses of the components of the purified enzyme were estimated to be 45, 43, and 11 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Based on the results of peptide mass fingerprint analysis, Acetochlor N-deethoxymethylase was identified as a cytochrome P450 system, composed of a cytochrome P450 oxygenase (43-kDa component; EthB), a ferredoxin (45 kDa; EthA), and a reductase (11 kDa; EthD), that is involved in the degradation of methyl tert-butyl ether. The gene cluster ethABCD was cloned by PCR amplification and expressed in Escherichia coli BL21(DE3). Resting cells of a recombinant E. coli strain showed deethoxymethylation activity against Acetochlor. Subcloning of ethABCD showed that ethABD expressed in E. coli BL21(DE3) has the activity of Acetochlor N-deethoxymethylase and is capable of converting Acetochlor to CMEPA.

  • degradation of Acetochlor by a bacterial consortium of rhodococcus sp t3 1 delftia sp t3 6 and sphingobium sp mea3 1
    Letters in Applied Microbiology, 2014
    Co-Authors: Ying Hou, Weiliang Dong, Fei Wang, Wenbiao Shen, Zhongli Cui
    Abstract:

    UNLABELLED Owing to Acetochlor persistence in the environment and its perceptible threats to the ecosystem and human health, it is urgent to search for effective approaches to decontaminate Acetochlor. In this study, an Acetochlor-degrading enrichment culture was obtained by continuous enrichment from Acetochlor-contaminated soil and named T3. T3 could completely degrade 100 mg l(-1) Acetochlor and butachlor within 6 days. Two bacterial strains Rhodococcus sp.T3-1 and Delftia sp.T3-6 and one strain Sphingobium sp.MEA3-1 were isolated and identified from T3 by using Acetochlor and MEA as sole carbon source, respectively. These three bacteria could completely mineralize Acetochlor by the cooperative metabolism. The biochemical pathway of Acetochlor degradation by these three bacteria in a consortium was proposed: Acetochlor to 2'-methyl-6'-ethyl-2-chloroacetanilide (CMEPA) by Rhodococcus sp. T3-1, CMEPA to 2-methyl-6-ethyl aniline (MEA) by Delftia sp.T3-6 and MEA by Sphingobium sp.MEA3-1 based on the identified degradation intermediates. Under laboratory conditions, the consortium was effective in the Acetochlor mineralization. SIGNIFICANCE AND IMPACT OF THE STUDY This study presents a bacterial consortium consisting of Rhodococcus sp.T3-1, Delftia sp.T3-6 and Sphingobium sp.MEA3-1 could completely mineralize Acetochlor by biochemical cooperation. The study reveals the metabolic mechanism of Acetochlor biodegradation and highlights the potential of the bacterial consortium for cleaning up Acetochlor and its metabolites subsisting in the environment.

Ying Hou - One of the best experts on this subject based on the ideXlab platform.

  • involvement of the cytochrome p450 system ethbad in the n deethoxymethylation of Acetochlor by rhodococcus sp strain t3 1
    Applied and Environmental Microbiology, 2015
    Co-Authors: Fei Wang, Ying Hou, Weiliang Dong, Jie Zhou, Yan Huang, Zhongli Cui
    Abstract:

    Acetochlor [2-chloro-N-(ethoxymethyl)-N-(2-ethyl-6-methylphenyl)-acetamide] is a widely applied herbicide with potential carcinogenic properties. N-Deethoxymethylation is the key step in Acetochlor biodegradation. N-Deethoxymethylase is a multicomponent enzyme that catalyzes the conversion of Acetochlor to 2′-methyl-6′-ethyl-2-chloroacetanilide (CMEPA). Fast detection of CMEPA by a two-enzyme (N-deethoxymethylase–amide hydrolase) system was established in this research. Based on the fast detection method, a three-component enzyme was purified from Rhodococcus sp. strain T3-1 using ammonium sulfate precipitation and hydrophobic interaction chromatography. The molecular masses of the components of the purified enzyme were estimated to be 45, 43, and 11 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Based on the results of peptide mass fingerprint analysis, Acetochlor N-deethoxymethylase was identified as a cytochrome P450 system, composed of a cytochrome P450 oxygenase (43-kDa component; EthB), a ferredoxin (45 kDa; EthA), and a reductase (11 kDa; EthD), that is involved in the degradation of methyl tert-butyl ether. The gene cluster ethABCD was cloned by PCR amplification and expressed in Escherichia coli BL21(DE3). Resting cells of a recombinant E. coli strain showed deethoxymethylation activity against Acetochlor. Subcloning of ethABCD showed that ethABD expressed in E. coli BL21(DE3) has the activity of Acetochlor N-deethoxymethylase and is capable of converting Acetochlor to CMEPA.

  • degradation of Acetochlor by a bacterial consortium of rhodococcus sp t3 1 delftia sp t3 6 and sphingobium sp mea3 1
    Letters in Applied Microbiology, 2014
    Co-Authors: Ying Hou, Weiliang Dong, Fei Wang, Wenbiao Shen, Zhongli Cui
    Abstract:

    UNLABELLED Owing to Acetochlor persistence in the environment and its perceptible threats to the ecosystem and human health, it is urgent to search for effective approaches to decontaminate Acetochlor. In this study, an Acetochlor-degrading enrichment culture was obtained by continuous enrichment from Acetochlor-contaminated soil and named T3. T3 could completely degrade 100 mg l(-1) Acetochlor and butachlor within 6 days. Two bacterial strains Rhodococcus sp.T3-1 and Delftia sp.T3-6 and one strain Sphingobium sp.MEA3-1 were isolated and identified from T3 by using Acetochlor and MEA as sole carbon source, respectively. These three bacteria could completely mineralize Acetochlor by the cooperative metabolism. The biochemical pathway of Acetochlor degradation by these three bacteria in a consortium was proposed: Acetochlor to 2'-methyl-6'-ethyl-2-chloroacetanilide (CMEPA) by Rhodococcus sp. T3-1, CMEPA to 2-methyl-6-ethyl aniline (MEA) by Delftia sp.T3-6 and MEA by Sphingobium sp.MEA3-1 based on the identified degradation intermediates. Under laboratory conditions, the consortium was effective in the Acetochlor mineralization. SIGNIFICANCE AND IMPACT OF THE STUDY This study presents a bacterial consortium consisting of Rhodococcus sp.T3-1, Delftia sp.T3-6 and Sphingobium sp.MEA3-1 could completely mineralize Acetochlor by biochemical cooperation. The study reveals the metabolic mechanism of Acetochlor biodegradation and highlights the potential of the bacterial consortium for cleaning up Acetochlor and its metabolites subsisting in the environment.

Fei Wang - One of the best experts on this subject based on the ideXlab platform.

  • involvement of the cytochrome p450 system ethbad in the n deethoxymethylation of Acetochlor by rhodococcus sp strain t3 1
    Applied and Environmental Microbiology, 2015
    Co-Authors: Fei Wang, Ying Hou, Weiliang Dong, Jie Zhou, Yan Huang, Zhongli Cui
    Abstract:

    Acetochlor [2-chloro-N-(ethoxymethyl)-N-(2-ethyl-6-methylphenyl)-acetamide] is a widely applied herbicide with potential carcinogenic properties. N-Deethoxymethylation is the key step in Acetochlor biodegradation. N-Deethoxymethylase is a multicomponent enzyme that catalyzes the conversion of Acetochlor to 2′-methyl-6′-ethyl-2-chloroacetanilide (CMEPA). Fast detection of CMEPA by a two-enzyme (N-deethoxymethylase–amide hydrolase) system was established in this research. Based on the fast detection method, a three-component enzyme was purified from Rhodococcus sp. strain T3-1 using ammonium sulfate precipitation and hydrophobic interaction chromatography. The molecular masses of the components of the purified enzyme were estimated to be 45, 43, and 11 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Based on the results of peptide mass fingerprint analysis, Acetochlor N-deethoxymethylase was identified as a cytochrome P450 system, composed of a cytochrome P450 oxygenase (43-kDa component; EthB), a ferredoxin (45 kDa; EthA), and a reductase (11 kDa; EthD), that is involved in the degradation of methyl tert-butyl ether. The gene cluster ethABCD was cloned by PCR amplification and expressed in Escherichia coli BL21(DE3). Resting cells of a recombinant E. coli strain showed deethoxymethylation activity against Acetochlor. Subcloning of ethABCD showed that ethABD expressed in E. coli BL21(DE3) has the activity of Acetochlor N-deethoxymethylase and is capable of converting Acetochlor to CMEPA.

  • degradation of Acetochlor by a bacterial consortium of rhodococcus sp t3 1 delftia sp t3 6 and sphingobium sp mea3 1
    Letters in Applied Microbiology, 2014
    Co-Authors: Ying Hou, Weiliang Dong, Fei Wang, Wenbiao Shen, Zhongli Cui
    Abstract:

    UNLABELLED Owing to Acetochlor persistence in the environment and its perceptible threats to the ecosystem and human health, it is urgent to search for effective approaches to decontaminate Acetochlor. In this study, an Acetochlor-degrading enrichment culture was obtained by continuous enrichment from Acetochlor-contaminated soil and named T3. T3 could completely degrade 100 mg l(-1) Acetochlor and butachlor within 6 days. Two bacterial strains Rhodococcus sp.T3-1 and Delftia sp.T3-6 and one strain Sphingobium sp.MEA3-1 were isolated and identified from T3 by using Acetochlor and MEA as sole carbon source, respectively. These three bacteria could completely mineralize Acetochlor by the cooperative metabolism. The biochemical pathway of Acetochlor degradation by these three bacteria in a consortium was proposed: Acetochlor to 2'-methyl-6'-ethyl-2-chloroacetanilide (CMEPA) by Rhodococcus sp. T3-1, CMEPA to 2-methyl-6-ethyl aniline (MEA) by Delftia sp.T3-6 and MEA by Sphingobium sp.MEA3-1 based on the identified degradation intermediates. Under laboratory conditions, the consortium was effective in the Acetochlor mineralization. SIGNIFICANCE AND IMPACT OF THE STUDY This study presents a bacterial consortium consisting of Rhodococcus sp.T3-1, Delftia sp.T3-6 and Sphingobium sp.MEA3-1 could completely mineralize Acetochlor by biochemical cooperation. The study reveals the metabolic mechanism of Acetochlor biodegradation and highlights the potential of the bacterial consortium for cleaning up Acetochlor and its metabolites subsisting in the environment.

Weiliang Dong - One of the best experts on this subject based on the ideXlab platform.

  • involvement of the cytochrome p450 system ethbad in the n deethoxymethylation of Acetochlor by rhodococcus sp strain t3 1
    Applied and Environmental Microbiology, 2015
    Co-Authors: Fei Wang, Ying Hou, Weiliang Dong, Jie Zhou, Yan Huang, Zhongli Cui
    Abstract:

    Acetochlor [2-chloro-N-(ethoxymethyl)-N-(2-ethyl-6-methylphenyl)-acetamide] is a widely applied herbicide with potential carcinogenic properties. N-Deethoxymethylation is the key step in Acetochlor biodegradation. N-Deethoxymethylase is a multicomponent enzyme that catalyzes the conversion of Acetochlor to 2′-methyl-6′-ethyl-2-chloroacetanilide (CMEPA). Fast detection of CMEPA by a two-enzyme (N-deethoxymethylase–amide hydrolase) system was established in this research. Based on the fast detection method, a three-component enzyme was purified from Rhodococcus sp. strain T3-1 using ammonium sulfate precipitation and hydrophobic interaction chromatography. The molecular masses of the components of the purified enzyme were estimated to be 45, 43, and 11 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Based on the results of peptide mass fingerprint analysis, Acetochlor N-deethoxymethylase was identified as a cytochrome P450 system, composed of a cytochrome P450 oxygenase (43-kDa component; EthB), a ferredoxin (45 kDa; EthA), and a reductase (11 kDa; EthD), that is involved in the degradation of methyl tert-butyl ether. The gene cluster ethABCD was cloned by PCR amplification and expressed in Escherichia coli BL21(DE3). Resting cells of a recombinant E. coli strain showed deethoxymethylation activity against Acetochlor. Subcloning of ethABCD showed that ethABD expressed in E. coli BL21(DE3) has the activity of Acetochlor N-deethoxymethylase and is capable of converting Acetochlor to CMEPA.

  • degradation of Acetochlor by a bacterial consortium of rhodococcus sp t3 1 delftia sp t3 6 and sphingobium sp mea3 1
    Letters in Applied Microbiology, 2014
    Co-Authors: Ying Hou, Weiliang Dong, Fei Wang, Wenbiao Shen, Zhongli Cui
    Abstract:

    UNLABELLED Owing to Acetochlor persistence in the environment and its perceptible threats to the ecosystem and human health, it is urgent to search for effective approaches to decontaminate Acetochlor. In this study, an Acetochlor-degrading enrichment culture was obtained by continuous enrichment from Acetochlor-contaminated soil and named T3. T3 could completely degrade 100 mg l(-1) Acetochlor and butachlor within 6 days. Two bacterial strains Rhodococcus sp.T3-1 and Delftia sp.T3-6 and one strain Sphingobium sp.MEA3-1 were isolated and identified from T3 by using Acetochlor and MEA as sole carbon source, respectively. These three bacteria could completely mineralize Acetochlor by the cooperative metabolism. The biochemical pathway of Acetochlor degradation by these three bacteria in a consortium was proposed: Acetochlor to 2'-methyl-6'-ethyl-2-chloroacetanilide (CMEPA) by Rhodococcus sp. T3-1, CMEPA to 2-methyl-6-ethyl aniline (MEA) by Delftia sp.T3-6 and MEA by Sphingobium sp.MEA3-1 based on the identified degradation intermediates. Under laboratory conditions, the consortium was effective in the Acetochlor mineralization. SIGNIFICANCE AND IMPACT OF THE STUDY This study presents a bacterial consortium consisting of Rhodococcus sp.T3-1, Delftia sp.T3-6 and Sphingobium sp.MEA3-1 could completely mineralize Acetochlor by biochemical cooperation. The study reveals the metabolic mechanism of Acetochlor biodegradation and highlights the potential of the bacterial consortium for cleaning up Acetochlor and its metabolites subsisting in the environment.

Richard G Burns - One of the best experts on this subject based on the ideXlab platform.

  • dissipation of Acetochlor and its distribution in surface and sub surface soil fractions during laboratory incubations
    Pest Management Science, 2005
    Co-Authors: Jason P Taylor, Margaret S Mills, Richard G Burns
    Abstract:

    Pesticides in soil are subject to a number of processes that result in transformation and biodegradation, sorption to and desorption from soil components, and diffusion and leaching. Pesticides leaching through a soil profile will be exposed to changing environmental conditions as different horizons with distinct physical, chemical and biological properties are encountered. The many ways in which soil properties influence pesticide retention and degradation need to be addressed to allow accurate predictions of environmental fate and the potential for groundwater pollution. Degradation and sorption processes were investigated in a long-term (100 days) study of the chloroacetanilide herbicide, Acetochlor. Soil cores were collected from a clay soil profile and samples taken from 0-30 cm (surface), 1.0-1.3 m (mid) and 2.7-3.0 m (deep) and treated with Acetochlor (2.5, 1.25, 0.67 microg Acetochlor g(-1) dry wt soil, respectively). In sterile and non-sterile conditions, Acetochlor concentration in the aqueous phase declined rapidly from the surface and subsoil layers, predominantly through nonextractable residue (NER) formation on soil surfaces, but also through biodegradation and biotic transformation. Abiotic transformation was also evident in the sterile soils. Several metabolites were produced, including Acetochlor-ethane sulphonic acid and Acetochlor-oxanilic acid. Transformation was principally microbial in origin, as shown by the differences between non-sterile and sterile soils. NER formation increased rapidly over the first 21 days in all soils and was mainly associated with the macroaggregate (>2000 microm diameter) size fractions. It is likely that Acetochlor is incorporated into the macroaggregates through oxidative coupling, as humification of particulate organic matter progresses. The dissipation (ie total loss of Acetochlor) half-life values were 9.3 (surface), 12.3 (mid) and 12.6 days (deep) in the non-sterile soils, compared with 20.9 [surface], 23.5 [mid], and 24 days [deep] in the sterile soils, demonstrating the importance of microbially driven processes in the rapid dissipation of Acetochlor in soil.