PMID- 27725981
OWN - NLM
STAT- MEDLINE
DCOM- 20180206
LR  - 20180206
IS  - 1463-9084 (Electronic)
IS  - 1463-9076 (Linking)
VI  - 18
IP  - 42
DP  - 2016 Oct 26
TI  - The role of extracellular DNA in uranium precipitation and biomineralisation.
PG  - 29101-29112
AB  - Bacterial extra polymeric substances (EPS) have been associated with the 
      extracellular precipitation of uranium. Here we report findings on the 
      biomineralisation of uranium, with extracellular DNA (eDNA) used as a model 
      biomolecule representative of EPS. The complexation and precipitation of eDNA 
      with uranium were investigated as a function of pH, ionic strength and varying 
      concentrations of reactants. The role of phosphate moieties in the 
      biomineralisation mechanism was studied by enzymatically releasing phosphate 
      (ePO(4)) from eDNA compared to abiotic phosphate (aPO(4)). The eDNA-uranium 
      precipitates and uranium minerals obtained were characterised by Attenuated Total 
      Reflectance-Fourier Transform Infrared (ATR-FT-IR) spectroscopy, Scanning 
      Electron Microscopy-Energy Dispersive X-Ray analysis (SEM-EDX), X-Ray Powder 
      Diffraction (XRD) and X-Ray Photoelectron Spectroscopy (XPS). ATR-FT-IR showed 
      that at pH 5, the eDNA-uranium precipitation mechanism was predominantly mediated 
      by interactions with phosphate moieties from eDNA. At pH 2, the uranium 
      interactions with eDNA occur mainly through phosphate. The solubility equilibrium 
      was dependent on pH with the formation of precipitate reduced as the pH 
      increased. The XRD data confirmed the formation of a uranium phosphate 
      precipitate when synthesised using ePO(4). XPS and SEM-EDX studies showed the 
      incorporation of carbon and nitrogen groups from the enzymatic orthophosphate 
      hydrolysis on the obtained precipitated. These results suggested that the removal 
      of uranium from solution occurs via two mechanisms: complexation by eDNA 
      molecules and precipitation of a uranium phosphate mineral of the type 
      (UO(2)HPO(4)).xH(2)O by enzymatic orthophosphate hydrolysis. This demonstrated 
      that eDNA from bacterial EPS is a key contributor to uranium biomineralisation.
FAU - Hufton, Joseph
AU  - Hufton J
AD  - Department of Geography, The University of Sheffield, Sheffield, S10 2TN, UK. 
      m.e.romero-gonzalez@sheffield.ac.uk.
FAU - Harding, John H
AU  - Harding JH
AD  - Department of Materials Science and Engineering, Sir Robert Hadfield Building, 
      University of Sheffield, Mappin Street, Sheffield, S1 3JD, UK.
FAU - Romero-Gonzalez, Maria E
AU  - Romero-Gonzalez ME
AUID- ORCID: 0000-0001-5808-5383
AD  - Department of Geography, The University of Sheffield, Sheffield, S10 2TN, UK. 
      m.e.romero-gonzalez@sheffield.ac.uk.
LA  - eng
PT  - Journal Article
PL  - England
TA  - Phys Chem Chem Phys
JT  - Physical chemistry chemical physics : PCCP
JID - 100888160
RN  - 0 (Phosphates)
RN  - 4OC371KSTK (Uranium)
RN  - 9007-49-2 (DNA)
SB  - IM
MH  - Alteromonadaceae/chemistry/genetics
MH  - Chemical Precipitation
MH  - DNA/*chemistry
MH  - Hydrogen-Ion Concentration
MH  - Microscopy, Electron, Scanning
MH  - Osmolar Concentration
MH  - Phosphates/chemistry
MH  - Photoelectron Spectroscopy
MH  - Spectroscopy, Fourier Transform Infrared
MH  - Uranium/*chemistry
EDAT- 2016/10/27 06:00
MHDA- 2018/02/07 06:00
CRDT- 2016/10/12 06:00
PHST- 2016/10/27 06:00 [pubmed]
PHST- 2018/02/07 06:00 [medline]
PHST- 2016/10/12 06:00 [entrez]
AID - 10.1039/c6cp03239g [doi]
PST - ppublish
SO  - Phys Chem Chem Phys. 2016 Oct 26;18(42):29101-29112. doi: 10.1039/c6cp03239g.