title: Uranium phosphate biomineralization by fungi.
abstract: Geoactive soil fungi were investigated for phosphatase-mediated uranium precipitation during growth on an organic phosphorus source. Aspergillus niger and Paecilomyces javanicus were grown on modified Czapek-Dox medium amended with glycerol 2-phosphate (G2P) as sole P source and uranium nitrate. Both organisms showed reduced growth on uranium-containing media but were able to extensively precipitate uranium and phosphorus-containing minerals on hyphal surfaces, and these were identified by X-ray powder diffraction as uranyl phosphate species, including potassium uranyl phosphate hydrate (KPUO6 .3H2 O), meta-ankoleite [(K1.7 Ba0.2 )(UO2 )2 (PO4 )2 .6H2 O], uranyl phosphate hydrate [(UO2 )3 (PO4 )2 .4H2 O], meta-ankoleite (K(UO2 )(PO4 ).3H2 O), uramphite (NH4 UO2 PO4 .3H2 O) and chernikovite [(H3 O)2 (UO2 )2 (PO4 )2 .6H2 O]. Some minerals with a morphology similar to bacterial hydrogen uranyl phosphate were detected on A. niger biomass. Geochemical modelling confirmed the complexity of uranium speciation, and the presence of meta-ankoleite, uramphite and uranyl phosphate hydrate between pH 3 and 8 closely matched the experimental data, with potassium as the dominant cation. We have therefore demonstrated that fungi can precipitate U-containing phosphate biominerals when grown with an organic source of P, with the hyphal matrix serving to localize the resultant uranium minerals. The findings throw further light on potential fungal roles in U and P biogeochemistry as well as the application of these mechanisms for element recovery or bioremediation.
authors.affiliation: Geomicrobiology Group, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, Scotland, UK.
authors.forename: Xinjin
authors.initials: X
authors.lastname: Liang
authors.affiliation: The James Hutton Institute, Craigiebuckler, Aberdeen, AB15 8QH, Scotland, UK.|Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
authors.forename: Stephen
authors.initials: S
authors.lastname: Hillier
authors.affiliation: The James Hutton Institute, Craigiebuckler, Aberdeen, AB15 8QH, Scotland, UK.
authors.forename: Helen
authors.initials: H
authors.lastname: Pendlowski
authors.affiliation: The James Hutton Institute, Craigiebuckler, Aberdeen, AB15 8QH, Scotland, UK.
authors.forename: Nia
authors.initials: N
authors.lastname: Gray
authors.affiliation: Geomicrobiology Group, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, Scotland, UK.|Laboratorio Biodiversità dei Funghi, Dipartimento di Biologia Ambientale, Sapienza Università di Roma, Rome, 00185, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Ceci
authors.affiliation: Geomicrobiology Group, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, Scotland, UK.|Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, China.
authors.forename: Geoffrey Michael
authors.initials: GM
authors.lastname: Gadd
mesh_terms: D001234:Aspergillus niger / Q000378:metabolism*; D001673:Biodegradation, Environmental; D005994:Glycerophosphates / Q000378:metabolism; D008903:Minerals / Q000378:metabolism; D010143:Paecilomyces / Q000378:metabolism*; D010710:Phosphates / Q000378:metabolism*; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D017974:Uranium Compounds / Q000378:metabolism*; D014961:X-Ray Diffraction
chemical_list: D005994:Glycerophosphates; D008903:Minerals; D010710:Phosphates; D012987:Soil; D017974:Uranium Compounds; C075963:hydrogen uranyl phosphate