Tetrachloromethane-Degrading Bacterial Enrichment Cultures and Isolates from a Contaminated Aquifer

摘要: The prokaryotic community of a groundwater aquifer exposed to high concentrations tetrachloromethane (CCl₄) for more than three decades was followed by terminal restriction fragment length polymorphism (T-RFLP) during pump-and-treat remediation at the contamination source. Bacterial enrichments and isolates were obtained under selective anoxic conditions, degraded 10 mg·L(-1) CCl₄, with less 10% transient formation chloroform. Dichloromethane chloromethane not detected. Several tetrachloromethane-degrading strains isolated from these enrichments, including bacteria Klebsiella Clostridium genera closely related previously described CCl₄ degrading bacteria, strain TM1, assigned genus Pelosinus, which this property yet described. Pelosinus sp. an oxygen-tolerant, Gram-positive bacterium strictly anaerobic metabolism, excreted thermostable metabolite into culture medium that allowed extracellular transformation. As estimated T-RFLP, phylotypes CCl₄-degrading enrichment cultures represented 7%, archaeal 0.5% total community.