Mechanisms for the Reduction of Actinides and Tc(VII) in Geobacter sulfurreducens

Technical Report · Tue Jun 01 00:00:00 EDT 2004

DOI:https://doi.org/10.2172/893683· OSTI ID:893683

Lloyd, Jonathan R

The mechanism of the reduction of U(VI) and Cr(VI) has now been studied in detail. Cr(VI) is reduced by one-electron transfer reactions to Cr(III), via a cell-bound Cr(V) intermediate identified by EPR spectroscopy. Studies with a cytochrome c7 mutant demonstrate that the electron transfer chain includes this protein which may be the terminal reductase for Cr(VI). Potential mechanisms of inhibition of Cr(III) precipitation, involving complex formation with organic acids commonly used as electron donors for metal reduction in the subsurface have also been identified. We have also initiated a collaboration with computational chemists led by Prof Ian Hillier in Manchester, to model metal binding to cytochrome c7, and subsequent electron transfer from the enzyme to the metal quantum mechanically.

• Research Organization: University of Manchester, Manchester, UK
• Sponsoring Organization: USDOE Office of Science (SC)
• OSTI ID: 893683
• Report Number(s): NABIR-1019572-2004; R&D Project: NABIR 1019572; TRN: US0606068
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
54 ENVIRONMENTAL SCIENCES
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ACTINIDES
BINDING ENERGY
CYTOCHROMES
ELECTRON TRANSFER
ELECTRONS
ENZYMES
MUTANTS
ORGANIC ACIDS
OXIDOREDUCTASES
PRECIPITATION
PROTEINS
SPECTROSCOPY
TRANSFER REACTIONS
VALENCE