Bioremediation of a Polluted Groundwater: Microbial Community Comparison of Treated and Untreated Aquifer through Next Generation Sequencing

Shallow Aquifer (A0) had been treated using a bioremediation approach through the amendment of whey in order to detoxify the most abundant contaminants represented by TeCA, PCE and TCE. In contrast, the deeper aquifer (A1), showing presence of TeCA and TCE, had not been treated. In A0, we observe a concomitant decrease of the initially more chlorinated molecules and an increase of less halogenated molecules such as TCA, DCE and VC suggesting that a reductive dechlorination has been taking place. Aquifer A1 did not show a significant decrease of the contaminants and detection of less substituted molecules was minimal. Microbial composition of A0 was very distinct from A1 showing a massive presence of the well-known dehalogenator Dehalococcoides mccartyi and a spectrum of different Geobacter species. In A0, metagenome assembly of shotgun data further indicates a significant presence of methanogenic archaea, most likely from class Methanomassiliicoccales, at a level comparable to that of Dehalococcoides mccartyi. Instead, A1 was characterized by a more diverse microbial population including species from Burkholderia and Polaromonas. The obtained metagenomic sequencing results showed that the autochthonous microbial consortia reflect the chemistry of the two aquifers, with a dominant population implicated in reductive dehalogenation in A0 and a population potentially capable of aerobic chlorinated hydrocarbon oxidation in A1.

PRETTO Patrizia;  SANSEVERINO Isabella;  DEMICHELIS Francesca;  LOTTI Francesca;  LAHM Armin;  GARCIA Angela;  RICCI Roberto;  LETTIERI Teresa; 

2022-08-18

MDPI

JRC121359

2073-4441 (online),   

https://www.mdpi.com/2073-4441/14/16/2456/htm,    https://publications.jrc.ec.europa.eu/repository/handle/JRC121359,   

10.3390/w14162456 (online),