These results demonstrate that gold

These results demonstrate that gold electrodes are a suitable
electron acceptor for G. sulfurreducens, functioning nearly as
well as graphite. This is significant because although gold is
highly conductive, it was not clear that microorganisms could
use a gold anode as an electron acceptor. Gold does not contain
the functional groups, such as quinones, that are present on
graphite surfaces and mimic the quinone-containing constituents
of natural microbial electron acceptors, such as humic substances.7
Furthermore, recent studies with the electricity-producing
microbe, S. putrefaciens, indicated that bare gold was not a suitable
anode material for microbial fuel cells