title: Effect of fungal hyphae on the access of bacteria to phenanthrene in soil.
abstract: The effect of fungal hyphae on the mobilization of soil-dwelling bacteria and their access to hydrophobic phenanthrene in soil was tested in columns containing air-filled agricultural soil. The experimental design included a spatial separation between zones of bacterial inoculation and contamination. Motile Pseudomonas putida PpG7 (NAH7) and fast-growing, hydrophilic Pythium ultimum were used as the model phenanthrene-degrading and vector organisms, respectively. Efficient translocation of strain PpG7 in the range of centimetres in presence of P. ultimum indicated that the fungal mycelia bridged air-filled pores and thereby provided a continuous network of water-paths that enabled bacteria to spread in the soil. Biodegradation of the soil-associated phenanthrene was found only in the presence of the fungal mycelia, hence proving that the fungal network facilitated the access of the bacteria to the contaminant. Our data suggest that the specific stimulation of indigenous fungi is a promising method to mobilize pollutant degrading bacteria and thereby improve soil bioremediation in-situ.
authors.affiliation: UFZ Centre for Environmental Research Leipzig-Halle, Department of Environmental Microbiology, 04318 Leipzig, Germany. lukas.wick@ufz.de
authors.forename: Lukas Y
authors.initials: LY
authors.lastname: Wick
authors.forename: Rita
authors.initials: R
authors.lastname: Remer
authors.forename: Birgit
authors.initials: B
authors.lastname: Würz
authors.forename: Jana
authors.initials: J
authors.lastname: Reichenbach
authors.forename: Sebastian
authors.initials: S
authors.lastname: Braun
authors.forename: Franziska
authors.initials: F
authors.lastname: Schäfer
authors.forename: Hauke
authors.initials: H
authors.lastname: Harms
mesh_terms: D001673:Biodegradation, Environmental; D025301:Hyphae / Q000166:cytology*; D009068:Movement / Q000502:physiology; D010616:Phenanthrenes / Q000378:metabolism*; D016958:Pseudomonas putida / Q000378:metabolism* / Q000502:physiology; D011775:Pythium / Q000166:cytology*; D012987:Soil / Q000032:analysis*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism*
chemical_list: D010616:Phenanthrenes; D012987:Soil; D012989:Soil Pollutants; C031181:phenanthrene