title: Application of a molecular based approach for the early detection of short term 3-chloroaniline shock loads on activated sludge bacterial community and functionality.
abstract: Microbial processes are central elements in wastewater treatment plants (WWTPs) to mineralize the organic matter, to degrade pollutants and to decrease the amount of suspended solids. This activity can be disrupted by organic and inorganic pollutants present in wastewater streams. Hence, it is of primary importance to investigate and monitor the structure and functionality of the sludge-resident microbial communities. We simulated a 3-chloroaniline (3-CA) shock load in 3-CA adapted and non-adapted semi-continuous activated-sludge (SCAS) reactors to selectively stress the Ammonia Oxidizing Bacteria (AOB). Recently developed setting-independent theoretical interpretation of molecular DNA and RNA fingerprinting patterns were used to evaluate the responses of the microbial populations. Ammonium accumulation in treated reactors upon 3-CA addition confirmed the disruption of the functionality under stress conditions. Molecular analyses coupled to their interpretation highlighted that shock loaded reactors clustered separately from non-treated ones, especially when AOBs community was specifically targeted. Furthermore, the interpretation of RNA-based analyses, as compared to DNA-based ones, allowed to more promptly depicting shifts in a stressed community. We showed that the use of RNA-based molecular tools in combination with a new set of parameters is a powerful tool to link functional failures with microbial structure modifications in WWTPs, providing a potential tool for a rational optimization of the processes (Microbial Resource Management - MRM).
authors.affiliation: Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Coupure Links 653, B9000 Gent, Belgium.
authors.forename: Massimo
authors.initials: M
authors.lastname: Marzorati
authors.forename: Andrea
authors.initials: A
authors.lastname: Negroni
authors.forename: Fabio
authors.initials: F
authors.lastname: Fava
authors.forename: Willy
authors.initials: W
authors.lastname: Verstraete
authors.forename: Nico
authors.initials: N
authors.lastname: Boon
mesh_terms: D000814:Aniline Compounds / Q000378:metabolism* / Q000494:pharmacology; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000378:metabolism; D015373:Bacterial Typing Techniques / Q000379:methods*; D019149:Bioreactors; D059013:Microbial Consortia / Q000502:physiology*; D017422:Sequence Analysis, DNA / Q000379:methods*; D017423:Sequence Analysis, RNA / Q000379:methods*; D012722:Sewage / Q000382:microbiology*; D014874:Water Pollutants, Chemical / Q000378:metabolism* / Q000494:pharmacology; D018508:Water Purification
chemical_list: D000814:Aniline Compounds; D012722:Sewage; D014874:Water Pollutants, Chemical; C031392:3-chloroaniline