Environmental Science & Technology,
Journal Year:
2023,
Volume and Issue:
57(7), P. 2739 - 2748
Published: Feb. 1, 2023
Adding
conductive
materials
to
the
cathode
of
a
microbial
electrochemical
system
(MES)
can
alter
route
interspecies
electron
transfer
and
kinetics
reduction
reactions.
We
tested
reductive
dechlorination
γ-hexachlorocyclohexane
(γ-HCH),
along
with
CH4
production,
in
MES
systems
whose
cathodes
were
coated
magnetite
nanoparticles
(NaFe),
biochar
(BC),
magnetic
(FeBC),
or
anti-conductive
silica
(SiBC).
Coating
NaFe
enriched
electroactive
microorganisms,
boosted
electro-bioreduction,
accelerated
γ-HCH
production.
In
contrast,
BC
only
dechlorination,
while
FeBC
methanogenesis,
because
their
assemblies
functional
taxa
that
selectively
transferred
electrons
those
sinks.
SiBC,
which
decreased
yielded
highest
production
increased
methanogens
mcrA
gene.
This
study
provides
strategy
control
distribution
between
methanogenesis
by
adding
MES's
cathode.
If
goal
is
maximize
minimize
methane
generation,
then
optimal
material.
accelerate
best
addition
NaFe.
increase
rate
SiBC
best.
Frontiers in Microbiology,
Journal Year:
2019,
Volume and Issue:
10
Published: Sept. 24, 2019
The
study
of
electrically
conductive
protein
nanowires
in
Geobacter
sulfurreducens
has
led
to
new
concepts
for
long-range
electron
extracellular
transport,
as
well
the
development
sustainable
materials
and
electronic
devices
with
novel
functions.
Until
recently,
pili
(e-pili),
assembled
from
PilA
pilin
monomer,
were
only
known
nanowires.
However,
filaments
comprised
multi-heme
c-type
cytochrome,
OmcS,
are
present
some
preparations
G.
outer-surface
proteins.
purpose
this
review
is
evaluate
available
evidence
on
vivo
expression
e-pili
OmcS
their
biological
function.
Abundant
literature
demonstrates
that
expresses
e-pili,
which
required
transport
Fe(III)
oxides
through
biofilms.
In
contrast,
there
no
definitive
yet
wild-type
express
long
extending
cells,
deleting
gene
actually
increases
biofilm
conductivity.
does
not
support
concern
many
previous
studies
mistakenly
studying
filaments.
For
example,
heterologous
aromatic-rich
monomer
metallireducens
conductivity
individual
more
than
5000-fold,
whereas
an
aromatic-poor
reduced
1000-fold.
This
million-fold
range
nanowire
was
achieved
while
maintaining
3
nm
diameter
characteristic
e-pili.
Purification
methods
eliminate
all
traces
yield
highly
e-pilin
microbes
do
produce
or
any
other
cytochromes.
Future
need
be
cognizant
importance
environmentally
relevant
growth
conditions
because
artificial
laboratory
culture
can
rapidly
select
against
expression.
Principles
derived
have
enabled
identification
non-cytochrome
diverse
bacteria
archaea.
A
similar
search
cytochrome
appendages
warranted.
Both
offer
design
options
synthesis
protein-based
'green'
electronics,
may
primary
driving
force
these
structures
near
future.
Advanced Materials,
Journal Year:
2020,
Volume and Issue:
33(6)
Published: Dec. 16, 2020
Abstract
Electrochemically
active
bacteria
can
transport
their
metabolically
generated
electrons
to
anodes,
or
accept
from
cathodes
synthesize
high‐value
chemicals
and
fuels,
via
a
process
known
as
extracellular
electron
transfer
(EET).
Harnessing
of
this
microbial
EET
has
led
the
development
bio‐electrochemical
systems
(BESs),
which
achieve
interconversion
electrical
chemical
energy
enable
electricity
generation,
hydrogen
production,
electrosynthesis,
wastewater
treatment,
desalination,
water
soil
remediation,
sensing.
Here,
focus
is
on
current
understanding
occurring
at
both
bacteria–electrode
interface
biotic
interface,
well
some
attempts
improve
by
using
various
nanomaterials.
The
behavior
nanomaterials
in
different
routes
influence
performance
BESs
are
described.
inherent
mechanisms
will
guide
rational
design
EET‐related
materials
lead
better
mechanisms.
