HR: 0830h
AN: B41D-0923    [PDF]
TI: Specific Detection and Direct Enumeration of Dehalococcoides sp. in a Chlorinated Solvent-Contaminated Aquifer
AU: * Kleikemper, J
EM: kleikemper@ito.umnw.ethz.ch
AF: Federal Institute of Technology, Zurich; Institute of Terrestrial Ecology, Grabenstr. 3, Schlieren, 8952 Switzerland
AU: Schroth, M H
EM: schroth@ito.umnw.ethz.ch
AF: Federal Institute of Technology, Zurich; Institute of Terrestrial Ecology, Grabenstr. 3, Schlieren, 8952 Switzerland
AU: Zeyer, J
EM: zeyer@ito.umnw.ethz.ch
AF: Federal Institute of Technology, Zurich; Institute of Terrestrial Ecology, Grabenstr. 3, Schlieren, 8952 Switzerland
AB: Chlorinated solvents are among the most important groundwater contaminants since spills are very hazardous and difficult to clean up. Biological degradation is a promising remediation technology. {\it Dehalococcoides ethenogenes} strain 195 is the only known organism that is capable of complete reductive dehalogenation of tetrachloroethene to the innocuous product ethene. Hence, methods that detect and quantify this organism in environmental samples are needed to assess and potentially optimize bioremediation efficiency. The objective of this study was to directly enumerate {\it Dehalococcoides} sp. in a chlorinated solvent-contaminated aquifer using fluorescence in situ hybridization with recently developed 16S rRNA-targeting probes (Yang and Zeyer, 2003; AEM 69(5), 2879-2883)). The presence of {\it Dehalococcoides} sp. was verified qualitatively using PCR and sequencing. Furthermore, occurrence of {\it Dehalococcoides} sp. was related to concentrations of ethene, chlorinated solvents (PCE, TCE, cDCE, VC) and redox conditions. This study demonstrates the successful application of a novel tool to quantify {\it Dehalococcoides} populations directly in contaminated environments.
DE: 0400 Biogeosciences
DE: 1803 Anthropogenic effects
DE: 1831 Groundwater quality
SC: Biogeosciences [B]
MN: 2003 Fall Meeting