Environmental Microbiology,
Год журнала:
2019,
Номер
21(4), С. 1255 - 1266
Опубликована: Март 9, 2019
Summary
This
study
coupled
a
landscape‐scale
metagenomic
survey
of
denitrification
gene
abundance
in
soils
with
situ
measurements
to
show
how
environmental
factors
shape
distinct
communities
that
exhibit
varying
activity.
Across
hydrologic
gradient,
the
distribution
total
genes
(
nap/nar
+
nirK/nirS
cNor/qNor
nosZ)
inferred
from
read
exhibited
no
consistent
patterns.
However,
when
were
considered
independently,
nirS
,
cNor
and
nosZ
was
positively
associated
areas
higher
soil
moisture,
nitrate
annual
rates,
whereas
nirK
qNor
negatively
these
factors.
These
results
suggest
conditions,
particular
moisture
nitrate,
select
for
are
characterized
by
differential
encoding
apparently
functionally
redundant
proteins.
In
contrast,
taxonomic
analysis
did
not
identify
notable
variability
denitrifying
community
composition
across
sites.
While
capacity
denitrify
ubiquitous
sites,
energetic
costs,
such
as
appear
confer
selective
advantage
microbial
experiencing
more
frequent
saturation
greater
inputs.
suggests
metagenomics
can
help
hotspots
could
be
protected
or
enhanced
treat
non‐point
source
nitrogen
pollution.
Nature,
Год журнала:
2024,
Номер
630(8016), С. 421 - 428
Опубликована: Май 29, 2024
Abstract
Farmed
soils
contribute
substantially
to
global
warming
by
emitting
N
2
O
(ref.
1
),
and
mitigation
has
proved
difficult
.
Several
microbial
nitrogen
transformations
produce
O,
but
the
only
biological
sink
for
is
enzyme
NosZ,
catalysing
reduction
of
3
).
Although
strengthening
NosZ
activity
in
would
reduce
emissions,
such
bioengineering
soil
microbiota
considered
challenging
4,5
However,
we
have
developed
a
technology
achieve
this,
using
organic
waste
as
substrate
vector
O-respiring
bacteria
selected
their
capacity
thrive
6–8
Here
analysed
biokinetics
our
most
promising
bacterium,
Cloacibacterium
sp.
CB-01,
its
survival
effect
on
emissions
field
experiments.
Fertilization
with
from
biogas
production,
which
CB-01
had
grown
aerobically
about
6
×
10
9
cells
per
millilitre,
reduced
50–95%,
depending
type.
The
strong
long-lasting
ascribed
tenacity
soil,
rather
than
biokinetic
parameters,
were
inferior
those
other
strains
bacteria.
Scaling
data
up
European
level,
find
that
national
anthropogenic
could
be
5–20%,
more
if
including
wastes.
This
opens
an
avenue
cost-effective
options
are
lacking
at
present.
Nature Communications,
Год журнала:
2024,
Номер
15(1)
Опубликована: Март 27, 2024
Abstract
Global
potent
greenhouse
gas
nitrous
oxide
(N
2
O)
emissions
from
soil
are
accelerating,
with
increases
in
the
proportion
of
reactive
nitrogen
emitted
as
N
O,
i.e.,
O
emission
factor
(EF).
Yet,
primary
controls
and
underlying
mechanisms
EFs
remain
unresolved.
Based
on
two
independent
but
complementary
global
syntheses,
three
field
studies
determining
effects
acidity
denitrifying
microorganisms,
we
show
that
pH
predominantly
by
affecting
denitrifier
community
composition.
Analysis
5438
paired
data
points
fluxes
revealed
a
hump-shaped
relationship
between
EFs,
highest
occurring
moderately
acidic
soils
favored
O-producing
over
O-consuming
induced
high
emissions.
Our
results
illustrate
has
unimodal
denitrifiers
net
depends
both
O/(N
+
)
ratio
overall
denitrification
rate.
These
findings
can
inform
strategies
to
predict
mitigate
under
future
input
scenarios.
Water Research,
Год журнала:
2018,
Номер
151, С. 381 - 387
Опубликована: Дек. 24, 2018
The
strong
greenhouse
gas
nitrous
oxide
(N2O)
can
be
emitted
from
wastewater
treatment
systems
as
a
byproduct
of
ammonium
oxidation
and
the
last
intermediate
in
stepwise
reduction
nitrate
to
N2
by
denitrifying
organisms.
A
potential
strategy
reduce
N2O
emissions
would
enhance
activity
reductase
(NOS)
microbial
community.
survey
existing
literature
on
denitrification
showed
that
reducing
capacity
(VmaxN2O→N2)
exceeded
produce
(VmaxNO3→N2O)
factor
2–10.
This
suggests
an
effective
sink
for
N2O,
potentially
scavenging
fraction
produced
or
abiotic
reactions.
We
conducted
series
incubation
experiments
with
freshly
sampled
activated
sludge
system
Oslo
found
ratio
α
=
VmaxN2O→N2/VmaxNO3→N2O
fluctuated
between
2
5
samples
taken
at
intervals
over
period
weeks.
Adding
cocktail
carbon
substrates
resulted
increasing
rates,
but
had
no
significant
effect
α.
Based
these
results
–
complemented
qPCR
metaproteomic
data
we
discuss
whether
overcapacity
ascribed
gene/protein
abundance
ratios
(nosZ/nir),
in-cell
competition
reductases
electrons
could
greater
importance.
Global Change Biology,
Год журнала:
2021,
Номер
27(12), С. 2669 - 2683
Опубликована: Фев. 6, 2021
Abstract
Many
biotic
and
abiotic
processes
contribute
to
nitrous
oxide
(N
2
O)
production
in
the
biosphere,
but
N
O
consumption
environment
has
heretofore
been
attributed
primarily
canonical
denitrifying
microorganisms.
The
nosZ
genes
encoding
reductase
enzyme,
NosZ,
responsible
for
reduction
dinitrogen
are
now
known
include
two
distinct
groups:
well‐studied
Clade
I
which
denitrifiers
typically
possess,
novel
II
possessed
by
diverse
groups
of
microorganisms,
most
non‐denitrifiers.
reducers
could
play
an
important,
previously
unrecognized
role
controlling
emissions
several
reasons,
including:
(1)
produced
other
than
denitrification,
(2)
hypothesized
non‐respiratory
functions
NosZ
as
electron
sink
or
detoxification,
(3)
possible
differing
enzyme
kinetics
compared
(4)
greater
gene
abundance
soils
many
ecosystems.
Despite
potential
ecological
significance
a
census
800
peer‐reviewed
original
research
articles
discussing
published
from
2013
2019
showed
that
percentage
evaluating
mentioning
increased
5%
only
22%
2019.
revealed
slowly
spreading
awareness
may
result
part
disciplinary
silos,
with
ranging
0%
Agriculture
Agronomy
journals
32%
Multidisciplinary
Sciences
journals.
In
addition,
inconsistent
nomenclature
,
17
different
terminologies
used
literature,
have
created
confusion
about
reducers.
We
provide
recommendations
accelerate
advances
understanding
diversity
regulating
soil
emissions.
Proceedings of the National Academy of Sciences,
Год журнала:
2018,
Номер
115(46), С. 11820 - 11825
Опубликована: Ноя. 1, 2018
When
oxygen
becomes
limiting,
denitrifying
bacteria
must
prepare
for
anaerobic
respiration
by
synthesizing
the
reductases
NAR
(NO3-
→
NO2-),
NIR
(NO2-
NO),
NOR
(2NO
N2O),
and
NOS
(N2O
N2),
either
en
bloc
or
sequentially,
to
avoid
entrapment
in
anoxia
without
energy.
Minimizing
metabolic
burden
of
this
precaution
is
a
plausible
fitness
trait,
we
show
that
model
denitrifier
Paracoccus
denitrificans
achieves
all
cells,
while
only
minority
synthesize
NIR.
Phenotypic
diversification
with
regards
ascribed
stochastic
initiation
gene
transcription,
which
autocatalytic
via
NO
production.
Observed
gas
kinetics
suggest
such
bet
hedging
widespread
among
bacteria.
Moreover,
response
oxygenation,
P.
preserves
poles
nongrowing
persister
ready
switch
sudden
anoxia.
Our
findings
add
dimensions
regulatory
biology
denitrification
identify
traits
decrease
N2O
emissions.
The ISME Journal,
Год журнала:
2021,
Номер
16(1), С. 26 - 37
Опубликована: Июль 1, 2021
Soil
pH
is
a
key
controller
of
denitrification.
We
analysed
the
metagenomics/transcriptomics
and
phenomics
two
soils
from
long-term
liming
experiment,
SoilN
(pH
6.8)
un-limed
SoilA
3.8).
had
severely
delayed
N
