sp. Strain IAE Dihaloeliminates 1,1,2-Trichloroethane and 1,2-Dichloroethane.

Chlorinated ethanes, including 1,2-dichloroethane (1,2-DCA) and 1,1,2-trichloroethane (1,1,2-TCA), are widespread groundwater contaminants. Enrichment cultures XR and XR derived from river sediment dihaloeliminated 1,2-DCA to ethene and 1,1,2-TCA to vinyl chloride (VC), respectively. The XR culture subsequently converted VC to ethene hydrogenolysis. Microbial community profiling demonstrated the enrichment of 16S rRNA gene sequences in both the XR and XR cultures, and () sequences were only detected in the ethene-producing XR culture. The presence of a novel population, designated as sp. strain IAE, was identified by the 16S rRNA gene-targeted polymerase chain reaction and Sanger sequencing. Time-resolved population dynamics attributed the dihaloelimination activity to strain IAE, which attained the growth yields of 0.93 ± 0.06 × 10 and 1.18 ± 0.14 × 10 cells per μmol Cl released with 1,2-DCA and 1,1,2-TCA as electron acceptors, respectively. In contrast, growth only occurred during VC-to-ethene hydrogenolysis. Our findings discover a sp. strain capable of respiring multiple chlorinated ethanes and demonstrate the involvement of a broader diversity of organohalide-respiring bacteria in the detoxification of 1,2-DCA and 1,1,2-TCA.