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Updated: Aug 14, 2026

Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
Reductive dechlorination of beta-hexachlorocyclohexane (beta-HCH) by a Dehalobacter species in coculture with a
Wim van Doesburg1, Miriam H A van Eekert, Peter J M Middeldorp
1Laboratory of Microbiology, Wageningen University and Research Centre, The Netherlands. wim.vandoesburg@wur.nl
Abstract:
An anaerobic coculture was enriched from a hexachlorocyclohexane (HCH) polluted soil. The coculture reductively dechlorinates the beta-HCH isomer to benzene and chlorobenzene in a ratio of 0.5-2 depending on the amount of beta-HCH degraded. The culture grows with H(2) as electron donor and beta-HCH as electron acceptor, indicating that dechlorination is a respiratory process. Phylogenetic analysis indicated that the coculture consists of two bacteria that are both related to gram-positive bacteria with a low G + C content of the DNA. One bacterium was identified as a Dehalobacter sp. This bacterium is responsible for the dechlorination. The other bacterium was isolated and characterized as being a Sedimentibacter sp. This strain is not able to dechlorinate beta-HCH. The Dehalobacter sp. requires the presence of Sedimentibacter for growth and dechlorination, but the function of the latter bacterium is not clear. This is the first report on the metabolic dechlorination of beta-HCH by a defined anaerobic bacterial culture.
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