In situ TCE degradation mediated by complex dehalorespiring communities during biostimulation processes

Eric Dugat-Bony (1) , Corinne Biderre-Petit (1) , Faouzi Jaziri (2) , Maude M. David (3) , Jérémie Denonfoux (1) , Delina Y. Lyon (3) , Jean-Yves Richard , Cyrille Curvers , Delphine Boucher (1) , Timothy M. Vogel (3) , Eric Peyretaillade (1) , Pierre Peyret (1)

1 LMGE - Laboratoire Microorganismes : Génome et Environnement
2 LIMOS - Laboratoire d'Informatique, de Modélisation et d'Optimisation des Systèmes
3 AMPERE - Ampère

The bioremediation of chloroethene contaminants in groundwater polluted systems is still a serious environmental challenge. Many previous studies have shown that cooperation of several dechlorinators is crucial for complete dechlorination of trichloroethene to ethene. In the present study, we used an explorative functional DNA microarray (DechloArray) to examine the composition of specific functional genes in groundwater samples in which chloroethene bioremediation was enhanced by delivery of hydrogen-releasing compounds. Our results demonstrate for the first time that complete biodegradation occurs through spatial and temporal variations of a wide diversity of dehalorespiring populations involving both Sulfurospirillum, Dehalobacter, Desulfitobacterium, Geobacter and Dehalococcoides genera. Sulfurospirillum appears to be the most active in the highly contaminated source zone, while Geobacter was only detected in the slightly contaminated downstream zone. The concomitant detection of both bvcA and vcrA genes suggests that at least two different Dehalococcoides species are probably responsible for the dechlorination of dichloroethenes and vinyl chloride to ethene. These species were not detected on sites where cis-dichloroethene accumulation was observed. These results support the notion that monitoring dechlorinators by the presence of specific functional biomarkers using a powerful tool such as DechloArray will be useful for surveying the efficiency of bioremediation strategies.

Mots clés: REDUCTIVE DEHALOGENASE GENES; 16S RIBOSOMAL-RNA; MULTIPLE DEHALOCOCCOIDES STRAINS; CHLOROETHENE-CONTAMINATED SITES; VINYL-CHLORIDE; CHLORINATED ETHENES; MOLECULAR CHARACTERIZATION; MICROBIAL COMMUNITY; FIELD DEMONSTRATION; RESPIRING BACTERIA

Domaines: Biotechnologies; Biotechnologie; Microbiologie et Parasitologie

Eric Dugat-Bony, Corinne Biderre-Petit, Faouzi Jaziri, Maude M. David, Jérémie Denonfoux, et al.. In situ TCE degradation mediated by complex dehalorespiring communities during biostimulation processes. Microbial Biotechnology, 2012, 5 (5 SI), pp.642-653. ⟨10.1111/j.1751-7915.2012.00339.x⟩. ⟨hal-00747255⟩