Résumé
Over 100 tons of the solvent tetrachloroethylene (PCE) were released into the environment (air, soil, water) during the year 2004. Unfortunately, PCE is degraded to metabolites, which are more toxic than the PCE. In some cases, these metabolites are further degraded to relatively harmless products such as ethylene. This study focused on the bacterial community structure during PCE degradation in order to evaluate the relationship between the microbial community and the accumulation of these toxic metabolites. Multiple microcosms supplied with different organic substrates were artificially contaminated with PCE. A thymine analog, bromodeoxyuridine was added to the microcosms and incorporated in the DNA double strand of the active cells. We compared the total and the active bacterial communities at different times by using phylogenic microarrays and pyrosequencing in order to identify microorganisms and functional genes associated with the complete PCE degradation to ethylene. In addition, the differential effects of the organic substrate addition on bacterial communities were analyzed by using phylogenic microarray.