Palau, JordiYu, R.Hatijah Mortan, C.Shouakar-Stash, O.Rosell, MònicaFreedman, D.Sbarbati, C.Fiorenza, S.Aravena, R.Marco-Urrea, E.Elsner, M.Soler i Gil, AlbertHunkeler, D.2020-06-022020-06-022017-02-140013-936Xhttps://hdl.handle.net/2445/163715This study investigates, for the first time, dual C-Cl isotope fractionation during anaerobic biodegradation of 1,2-dichloroethane (1,2-DCA) via dihaloelimination by Dehalococcoides and Dehalogenimonas-containing enrichment cultures. Isotopic fractionation of 1,2-DCA (εbulkC and εbulkCl) for Dehalococcoides (−33.0 ± 0.4¿ and −5.1 ± 0.1¿) and Dehalogenimonas-containing microcosms (−23 ± 2¿ and −12.0 ± 0.8¿) resulted in distinctly different dual element C-Cl isotope correlations (Λ = Δδ13C/Δδ37Cl ≈ εbulkC/εbulkCl), 6.8 ± 0.2 and 1.89 ± 0.02, respectively. Determined isotope effects and detected products suggest that the difference on the obtained Λ values for biodihaloelimination could be associated with a different mode of concerted bond cleavage rather than two different reaction pathways (i.e., stepwise vs concerted). Λ values of 1,2-DCA were, for the first time, determined in two field sites under reducing conditions (2.1 ± 0.1 and 2.2 ± 2.9). They were similar to the one obtained for the Dehalogenimonas-containing microcosms (1.89 ± 0.02) and very different from those reported for aerobic degradation pathways in a previous laboratory study (7.6 ± 0.1 and 0.78 ± 0.03). Thus, this study illustrates the potential of a dual isotope analysis to differentiate between aerobic and anaerobic biodegradation pathways of 1,2-DCA in the field and suggests that this approach might also be used to characterize dihaloelimination of 1,2-DCA by different bacteria, which needs to be confirmed in future studies.10 p.application/pdfeng(c) American Chemical Society , 2017Degradació dels sòlsBiodegradacióIsòtopsSoil degradationBiodegradationIsotopesinfo:eu-repo/semantics/article6624792020-06-02info:eu-repo/semantics/openAccess