title: Long-term ferrocyanide application via deicing salts promotes the establishment of Actinomycetales assimilating ferrocyanide-derived carbon in soil.
abstract: Cyanides are highly toxic and produced by various microorganisms as defence strategy or to increase their competitiveness. As degradation is the most efficient way of detoxification, some microbes developed the capability to use cyanides as carbon and nitrogen source. However, it is not clear if this potential also helps to lower cyanide concentrations in roadside soils where deicing salt application leads to significant inputs of ferrocyanide. The question remains if biodegradation in soils can occur without previous photolysis. By conducting a microcosm experiment using soils with/without pre-exposition to road salts spiked with (13) C-labelled ferrocyanide, we were able to confirm biodegradation and in parallel to identify bacteria using ferrocyanide as C source via DNA stable isotope probing (DNA-SIP), TRFLP fingerprinting and pyrosequencing. Bacteria assimilating (13) C were highly similar in the pre-exposed soils, belonging mostly to Actinomycetales (Kineosporia, Mycobacterium, Micromonosporaceae). In the soil without pre-exposition, bacteria belonging to Acidobacteria (Gp3, Gp4, Gp6), Gemmatimonadetes (Gemmatimonas) and Gammaproteobacteria (Thermomonas, Xanthomonadaceae) used ferrocyanide as C source but not the present Actinomycetales. This indicated that (i) various bacteria are able to assimilate ferrocyanide-derived C and (ii) long-term exposition to ferrocyanide applied with deicing salts leads to Actinomycetales outcompeting other microorganisms for the use of ferrocyanide as C source.
authors.affiliation: Research Unit Environmental Genomics, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Ingolstädter Landstraße 1, Neuherberg, 85764, Germany.
authors.forename: Silvia
authors.initials: S
authors.lastname: Gschwendtner
authors.affiliation: Department Geowissenschaften, Bodengeographie/Bodenkunde, Universität zu Köln, Albertus-Magnus-Platz, Köln, 50923, Germany.
authors.forename: Tim
authors.initials: T
authors.lastname: Mansfeldt
authors.affiliation: Research Unit Environmental Genomics, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Ingolstädter Landstraße 1, Neuherberg, 85764, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Kublik
authors.affiliation: Research Unit Environmental Genomics, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Ingolstädter Landstraße 1, Neuherberg, 85764, Germany.
authors.forename: Evangelia
authors.initials: E
authors.lastname: Touliari
authors.affiliation: Institute of Biochemical Plant Pathology, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Ingolstädter Landstraße 1, Neuherberg, 85764, Germany.
authors.forename: Franz
authors.initials: F
authors.lastname: Buegger
authors.affiliation: Research Unit Environmental Genomics, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Ingolstädter Landstraße 1, Neuherberg, 85764, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Schloter
mesh_terms: D000192:Actinomycetales / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism*; D058448:Biota / Q000187:drug effects; D001711:Biotransformation; D002244:Carbon / Q000378:metabolism*; D005295:Ferrocyanides / Q000378:metabolism*; D007553:Isotope Labeling; D012150:Polymorphism, Restriction Fragment Length; D012492:Salts / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology
chemical_list: D005295:Ferrocyanides; D012492:Salts; D002244:Carbon; C020354:hexacyanoferrate II