bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2023,
Volume and Issue:
unknown
Published: July 26, 2023
Abstract
Anaerobic
microbial
corrosion
of
iron-containing
metals
causes
extensive
economic
damage.
Some
microbes
are
capable
direct
metal-to-microbe
electron
transfer
(electrobiocorrosion),
but
the
prevalence
electrobiocorrosion
among
diverse
methanogens
and
acetogens
is
poorly
understood
because
a
lack
tools
for
their
genetic
manipulation.
Previous
studies
have
suggested
that
respiration
with
316L
stainless
steel
as
donor
indicative
because,
unlike
pure
Fe
0
,
does
not
abiotically
generate
H
2
an
intermediary
carrier.
Here
we
report
all
(
Methanosarcina
vacuolata
Methanothrix
soehngenii
Methanobacterium
strain
IM1)
Sporomusa
ovata
Clostridium
ljungdahlii
)
evaluated
respired
donor,
only
M.
Mx
S.
were
electrobiocorrosion.
The
electrobiocorrosive
required
acetate
additional
energy
source
in
order
to
produce
methane
from
steel.
Co-cultures
Mx.
demonstrated
how
can
provide
during
corrosion.
Not
was
IM1
electrobiocorrosion,
it
also
did
accept
electrons
Geobacter
metallireducens
effective
electron-
donating
partner
interspecies
directly
.
finding
despite
outer-surface
c
-type
cytochromes
previously
found
be
important
other
microbes,
demonstrates
there
multiple
strategies
making
electrical
contact
Impact
Statement
Understanding
anaerobic
receive
likely
lead
novel
mitigating
metals,
which
has
enormous
impact.
Electrobiocorrosion,
relatively
recently
recognized
mechanism.
It
cultures
when
oxidation
inhibited
by
deletion
genes
known
involved
forms
extracellular
exchange.
However,
many
obvious
connections
difficult
genetically
manipulate.
study
reported
here
provides
alternative
approach
evaluating
whether
require
results
indicate
IM1,
electrobiocorrosive,
contrast
previous
speculation.
some
without
do
appear
suggesting
this
mechanism
may
more
widespread
than
thought.
Proceedings of the National Academy of Sciences,
Journal Year:
2023,
Volume and Issue:
120(39)
Published: Sept. 20, 2023
Anaerobic
marine
environments
are
the
third
largest
producer
of
greenhouse
gas
methane.
The
release
to
atmosphere
is
prevented
by
anaerobic
‘methanotrophic
archaea
(ANME)
dependent
on
a
symbiotic
association
with
sulfate-reducing
bacteria
or
direct
reduction
metal
oxides.
Metagenomic
analyses
ANME
consistent
reverse
methanogenesis
pathway,
although
no
wild-type
isolates
have
been
available
for
validation
and
biochemical
investigation.
Herein
reported
characterization
methanotrophic
growth
diverse
methanogens
Methanosarcina
acetivorans
C2A
Methanococcoides
orientis
sp.
nov.
Growth
was
either
ferrihydrite
humic
acids
revealing
respiratory
mode
energy
conservation.
Acetate
and/or
formate
were
end
products.
Reversal
well-characterized
methanogenic
pathways
remarkably
like
consensus
uncultured
based
extensive
metagenomic
analyses.
mLife,
Journal Year:
2024,
Volume and Issue:
3(2), P. 269 - 276
Published: June 1, 2024
Abstract
Sulfate‐reducing
microorganisms
extensively
contribute
to
the
corrosion
of
ferrous
metal
infrastructure.
There
is
substantial
debate
over
their
mechanisms.
We
investigated
Fe
0
with
Desulfovibrio
vulgaris
,
sulfate
reducer
most
often
employed
in
studies.
Cultures
were
grown
both
lactate
and
as
potential
electron
donors
replicate
common
environmental
condition
which
organic
substrates
help
fuel
growth
corrosive
microbes.
was
corroded
cultures
a
D.
hydrogenase‐deficient
mutant
1:1
correspondence
between
loss
H
2
accumulation
expected
for
oxidation
coupled
+
reduction
.
This
result
extent
indicated
that
not
capable
direct
‐to‐microbe
transfer
even
though
it
provided
supplementary
energy
source
presence
abundant
sulfide.
Corrosion
greater
than
sterile
controls,
demonstrating
removal
necessary
enhanced
observed
The
parental
‐consuming
strain
more
strain,
could
be
attributed
reduction,
producing
sulfide
further
stimulated
oxidation.
results
suggest
consumption
microbially
corrosion,
but
can
indirectly
promote
by
increasing
generation
from
reduction.
finding
incapable
uptake
reaffirms
metal‐to‐microbe
has
yet
rigorously
described
sulfate‐reducing
Angewandte Chemie,
Journal Year:
2023,
Volume and Issue:
135(38)
Published: Aug. 1, 2023
Abstract
Electrobiocorrosion,
the
process
in
which
microbes
extract
electrons
from
metallic
iron
(Fe
0
)
through
direct
Fe
‐microbe
electrical
connections,
is
thought
to
contribute
costly
corrosion
of
iron‐containing
metals
that
impacts
many
industries.
However,
electrobiocorrosion
mechanisms
are
poorly
understood.
We
report
here
electrically
conductive
pili
(e‐pili)
and
mineral
magnetite
play
an
important
role
electron
transfer
between
Geobacter
sulfurreducens
,
first
microbe
has
been
rigorously
documented.
Genetic
modification
express
substantially
diminished
corrosive
pitting
rates
‐to‐microbe
flux.
Magnetite
reduced
resistance
transfer,
increasing
currents
intensifying
pitting.
Studies
with
mutants
suggested
promoted
a
manner
similar
outer‐surface
c
‐type
cytochrome
OmcS.
These
findings,
fact
common
product
corrosion,
suggest
potential
positive
feedback
loop
produced
during
further
accelerating
electrobiocorrosion.
The
interactions
e‐pili,
cytochromes,
demonstrate
mechanistic
complexities
electrobiocorrosion,
but
also
provide
insights
into
detecting
possibly
mitigating
this
economically
damaging
process.
