Reduction of U(VI) by the deep subsurface bacterium, Thermus scotoductus SA-01, and the involvement of the ABC transporter protein

Chemosphere. 2012 Feb;86(6):572-7. doi: 10.1016/j.chemosphere.2011.10.006. Epub 2011 Nov 16.


In this study we investigated the effect of uranium on the growth of the bacterium Thermus scotoductus strain SA-01 as well as the whole cell U(VI) reduction capabilities of the organism. Also, site-directed mutagenesis confirmed the identity of a protein capable of a possible alternative mechanism of U(VI) reduction. SA-01 can grow aerobically in up to 1.25 mM uranium and has the capability to reduce low levels of U(VI) in under 20 h. TEM analysis performed on cells exposed to uranium showed extracellular and membrane-bound accumulation of uranium. The reductase-like protein was surprisingly identified as a peptide ABC transporter, peptide-binding protein. This study showcases the concept of protein promiscuity, where this protein with a distinct function in situ can also have the unintended function of a reactant for the reduction of U(VI).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP-Binding Cassette Transporters / chemistry
  • ATP-Binding Cassette Transporters / genetics
  • ATP-Binding Cassette Transporters / metabolism*
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Biodegradation, Environmental
  • Electron Transport
  • Environmental Pollutants / isolation & purification
  • Environmental Pollutants / metabolism*
  • Environmental Pollutants / toxicity
  • Models, Molecular
  • Mutation
  • Oxidoreductases / isolation & purification
  • Oxidoreductases / metabolism
  • Protein Conformation
  • Thermus / cytology
  • Thermus / drug effects
  • Thermus / enzymology
  • Thermus / metabolism*
  • Uranium / isolation & purification
  • Uranium / metabolism*
  • Uranium / toxicity


  • ATP-Binding Cassette Transporters
  • Bacterial Proteins
  • Environmental Pollutants
  • Uranium
  • Oxidoreductases