ISOLATION OF A BACTERIUM THAT REDUCTIVELY DECHLORINATES TETRACHLOROETHENE TO ETHENE

Tetrachloroethene is a prominent groundwater pollutant that can be red uctively dechlorinated by mixed anaerobic microbial populations to the nontoxic product ethene. Strain 195, a coccoid bacterium that dechlor inates tetrachloroethene to ethene, was isolated and characterized. Gr owth of strain 195 with H-2 and tetrachloroethene as the electron dono r and acceptor pair required extracts from mixed microbial cultures. G rowth of strain I 195 was resistant to ampicillin and vancomycin; its cell wall did not react with a peptidoglycan-specific lectin and its u ltrastructure resembled S-layers of Archaea. Analysis of the 16S ribos omal DNA sequence of strain 195 indicated that it is a eubacterium wit hout close affiliation to any known groups.