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Updated: Jun 4, 2025
15:19
Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
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Dehalogenimonas Strain W from Estuarine Sediments Dechlorinates 1,2-Dichloroethane under Elevated Salinity
Hongyan Wang1,2, Huijuan Jin1, Jingjing Wang1
1Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning 110016, China.
Environmental Science & Technology
|December 26, 2024
Summary
This study identifies a new Dehalogenimonas strain from estuarine sediments capable of dechlorinating 1,2-dichloroethane in high salinity. This discovery highlights the potential of organohalide-respiring bacteria in marine environments.
Area of Science:
- Environmental microbiology
- Biogeochemical cycling
Background:
- Organohalide-respiring bacteria (OHRB) are crucial for detoxifying halogenated organic compounds (HOCs).
- Limited knowledge exists on OHRB diversity and survival strategies in high-salinity environments like estuaries and oceans.
Purpose of the Study:
- To characterize an OHRB from estuarine sediments with high-salinity dechlorination capabilities.
- To identify the mechanisms enabling OHRB to function in saline conditions.
Main Methods:
- Enrichment culture from estuarine sediments.
- Characterization of 1,2-dichloroethane (1,2-DCA) dechlorination under elevated salinity (≥5.1% NaCl).
- Metagenomic and proteomic analyses to identify key enzymes.
Main Results:
- Isolation of a Dehalogenimonas strain W capable of dechlorinating 1,2-DCA to ethene at high salinity.
- Identified a putative reductive dehalogenase (DdeA) as the primary enzyme for high-salinity dechlorination.
- Ectoine biosynthesis enzymes (EctABC) were found to contribute to salt tolerance.
Conclusions:
- Dehalogenimonas strains possess the capability to detoxify HOCs in high-salinity estuarine and marine ecosystems.
- The DdeA enzyme and ectoine biosynthesis are key adaptive mechanisms for OHRB in saline environments.
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