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

Lloyd, Jonathan R.

University of Manchester

关键词: Cytochromes;    Oxidoreductases;    Enzymes;    Actinides;    59 Basic Biological Sciences;   

DOI  :  10.2172/893683
RP-ID  :  NABIR-1019572-2004
RP-ID  :  None
RP-ID  :  893683

美国|英语

来源: UNT Digital Library

【 摘 要 】

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.