INTERNATIONAL BIODETERIORATION & BIODEGRADATION
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2022
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IF 4.907
Shunli Hu,Long Zhang,Guiping Liu,Yufeng Gan,Baozhan Wang,Fang Wang,Jiandong Jiang
Rac-dichlorprop [( R , S )-2-(2,4-dichlorophenoxy)propanoic acid], a commonly used chiral phenoxyalkanoic acid herbicide, is frequently detected in various environments, posing threats to human health and environmental safety. The ( S )-enantiomer of dichlorprop shows a lower herbicidal activity but a higher toxicity as compared to the ( R )-enantiomer of dichlorprop. It is of great importance to enantioselectively remove the non-herbicidal ( S )-dichlorprop from the rac -dichlorprop in the application sites. In this study, the dissipation of ( R )- and ( S )-dichlorprop in an agricultural soil was investigated. We found that the dissipation rate of ( S )-dichlorprop was higher than that of ( R )-dichlorprop in an agricultural soil. Although the influences of different enantiomers of dichlorprop on soil bacterial community were not different, Sphingobium was significantly enriched in the ( S )-dichlorprop-treated soil as compared to ( R )-dichlorprop, indicating that Sphingobium species played important roles in the dissipation of ( S )-dichlorprop. Furthermore, a bacterial consortium containing Sphingobium sp. strain SP-2 (enantioselectively transforming ( S )-dichlorprop to 2,4-dichlorophenol) and Sphingopyxis sp. strain DP-21 (mineralizing 2,4-dichlorophenol), which synergistically mineralized the ( S )-enantiomer of dichlorprop, was isolated from the agricultural soil. Bioaugmentation with the in-situ isolated consortium (strains SP-2 and DP-21) resulted in the enhanced removal of the non-herbicidal ( S )-dichlorprop from the soil and in the adaptation of the inoculated degrading strains. This study offers new insights into the enhanced bioremediation of the non-herbicidal ( S )-dichlorprop contaminated soils while simultaneously ensuring environmental safety and crop yield.
研究领域:
环境科学
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微生物学
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土壤学
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生物修复
✓ 已验证
DOI
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
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2021
·Vol. 87
·期 22
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IF 4.792
Shunli Hu,Guiping Liu,Long Zhang,Yufeng Gan,Baozhan Wang,Shiri Freilich,Jiandong Jiang
rac-Dichlorprop, a commonly used phenoxyalkanoic acid herbicide, is frequently detected in environments and poses threats to environmental safety and human health. Microbial consortia are thought to play key roles in rac-dichlorprop degradation. However, the compositions of the microbial consortia involved in rac-dichlorprop degradation remain largely unknown. In this study, DNA stable isotope probing (SIP) and metagenomic analysis were integrated to reveal the key microbial consortium responsible for rac-dichlorprop degradation in a rac-dichlorprop-degrading enrichment. OTU340 (Sphingobium sp.) and OTU348 (Sphingopyxis sp.) were significantly enriched in the rac-[13C]dichlorprop-labeled heavy DNA fractions. A rac-dichlorprop degrader, Sphingobium sp. strain L3, was isolated from the enrichment by a traditional enrichment method but with additional supplementation of the antibiotic ciprofloxacin, which was instructed by metagenomic analysis of the associations between rac-dichlorprop degraders and antibiotic resistance genes. As revealed by functional profiling of the metagenomes of the heavy DNA, the genes rdpA and sdpA, involved in the initial degradation of the (R)- and (S)-enantiomers of dichlorprop, respectively, were mostly taxonomically assigned to Sphingobium species, indicating that Sphingopyxis species might harbor novel dichlorprop-degrading genes. In addition, taxonomically diverse bacterial genera such as Dyella, Sphingomonas, Pseudomonas, and Achromobacter were presumed to synergistically cooperate with the key degraders Sphingobium/Sphingopyxis for enhanced degradation of rac-dichlorprop.IMPORTANCE Understanding of the key microbial consortium involved in the degradation of the phenoxyalkanoic acid herbicide rac-dichlorprop is pivotal for design of synergistic consortia used for enhanced bioremediation of herbicide-contaminated sites. However, the composition of the microbial consortium and the interactions between community members during the biodegradation of rac-dichlorprop are unclear. In this study, DNA-SIP and metagenomic analysis were integrated to reveal that the metabolite 2,4-dichlorophenol degraders Dyella, Sphingomonas, Pseudomonas, and Achromobacter synergistically cooperated with the key degraders Sphingobium/Sphingopyxis for enhanced degradation of rac-dichlorprop. Our study provides new insights into the synergistic degradation of rac-dichlorprop at the community level and implies the existence of novel degrading genes for rac-dichlorprop in nature.
研究领域:
环境微生物学
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基因组学
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生物修复
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2023
·
IF 9.8
Yijie Chen,Zhen Zhen,Gaoyang Li,Huijun Li,Ting Wei,Fengcheng Huang,Tao Li,Changhong Yang,Lei Ren,Yanqiu Liang,Zhong Lin,Dayi Zhang
Di-2-ethylhexyl phthalate (DEHP) is a widespread persistent organic pollutant in the environment. As an ultimate barrier preventing pollutant entry into the ocean, mangrove plays an important role in coastal ecosystem. However, little information is known about DEHP degradation in mangrove rhizosphere. In this study, a rhizobox was used to separate four consecutive rhizosphere compartments with distance of 0–2, 2–4, 4–6, and > 6 mm to the rhizoplane of Kandelia obovata and investigate DEHP gradient degradation behavior in rhizosphere. Sediments closer to the rhizoplane exhibited higher DEHP degradation efficiencies (74.4 % in 0–2 mm layer). More precisely, mangrove rhizosphere promoted the benzoic acid pathway and non-selectively accelerated the production of mono(2-ethylhexyl) phthalate, phthalic acid and benzoic acid. Higher sediment organic matter content, lower pH and less humus in rhizosphere benefited DEHP hydrolysis. In addition, rhizosphere significantly increased microbial biomass and activities comparing to bulk sediments. Some bacterial lineages with potential DEHP degradation capability exhibited a distance-dependent pattern that decreased with the distance to the rhizoplane, including Bacillales , Acidothermaceae , Gammaproteobacteria , and Sphingobacteriales . Our findings suggested that mangrove rhizosphere could accelerate DEHP degradation by altering sediment physicochemical properties and microbial composition, showing positive effects on coastal ecosystem services for eliminating phthalate acid ester contamination.
研究领域:
环境科学
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微生物学
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生态学
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污染物降解
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）