Development and characterization of DehaloR2, a novel anaerobic microbial consortium performing rapid dechlorination of TCE to ethene

作者：Ziv El Michal; Delgado Anca G; Yao Ying; Kang Dae Wook; Nelson Katherine G; Halden Rolf U; Krajmalnik Brown Rosa^*

来源：Applied Microbiology and Biotechnology, 2011, 92(5): 1063-1071.

DOI：10.1007/s00253-011-3388-y

• Dehalococcoides
• Chlorinated ethenes
• Sediment microorganisms
• Reductive dechlorination

A novel anaerobic consortium, named DehaloR boolean AND 2, that performs rapid and complete reductive dechlorination of trichloroethene (TCE) to ethene is described. DehaloR boolean AND 2 was developed from estuarine sediment from the Back River of the Chesapeake Bay and has been stably maintained in the laboratory for over 2 years. Initial sediment microcosms showed incomplete reduction of TCE to DCE with a ratio of trans- to cis- isomers of 1.67. However, complete reduction to ethene was achieved within 10 days after transfer of the consortium to sediment-free media and was accompanied by a shift to cis-DCE as the prevailing intermediate metabolite. The microbial community shifted from dominance of the Proteobacterial phylum in the sediment to Firmicutes and Chloroflexi in DehaloR boolean AND 2, containing the genera Acetobacterium, Clostridium, and the dechlorinators Dehalococcoides. Also present were Spirochaetes, possible acetogens, and Geobacter which encompass previously described dechlorinators. Rates of TCE to ethene reductive dechlorination reached 2.83 mM Cl- d(-1) in batch bottles with a Dehalococcoides sp. density of 1.54E+11 gene copies per liter, comparing favorably to other enrichment cultures described in the literature and identifying DehaloR boolean AND 2 as a promising consortium for use in bioremediation of chlorinated ethene-impacted environments.

• 出版日期2011-12