In Situ Spectral Kinetics of Cr(VI) Reduction by c-Type Cytochromes in A Suspension of Living Shewanella putrefaciens 200.

ABSTRACT: Although c-type cytochromes (c-Cyts) mediating metal reduction have been mainly investigated with in vitro purified proteins of dissimilatory metal reducing bacteria, the in vivo behavior of c-Cyts is still unclear given the difficulty in measuring the proteins of intact cells. Here, c-Cyts in living Shewanella putrefaciens 200 (SP200) was successfully quantified using diffuse-transmission UV/Vis spectroscopy due to the strong absorbance of hemes, and the in situ spectral kinetics of Cr(VI) reduction by c-Cyts were examined over time. The reduced product Cr(III) observed on the cell surface may play a role in inhibiting the Cr(VI) reduction and reducing the cell numbers with high concentrations (>200 μM) of Cr(VI) evidenced by the 16S rRNA analysis. A brief kinetic model was established wi

SUBMITTER: Liu T 

PROVIDER: S-EPMC4939527 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature