Frontiers in Microbiology,
Год журнала:
2020,
Номер
11
Опубликована: Окт. 6, 2020
Complete
ammonia
oxidizers
(comammox),
able
to
individually
oxidize
nitrate,
are
considered
play
a
significant
role
in
the
global
nitrogen
cycle.
However,
distribution
of
comammox
Nitrospira
estuarine
tidal
flat
wetland
and
environmental
drivers
affecting
their
abundance
diversity
remain
unknown.
Here,
we
present
large-scale
investigation
on
geographical
along
wetlands
China,
where
were
successfully
detected
9
16
sampling
sites.
The
ranged
from
4.15
×
105
6.67
106
copies/g,
2.21-
5.44-folds
lower
than
canonical
oxidizers:
ammonia-oxidizing
bacteria
(AOB)
archaea
(AOA).
Phylogenetic
analysis
based
alpha
subunit
monooxygenase
encoding
gene
(amoA)
revealed
that
Clade
A,
mainly
originating
upstream
river
inputs,
accounts
for
more
80%
Nitrospira,
whereas
clade
B
rarely
detected.
Comammox
dominant
OTUs
varied
within
samples,
showing
pattern.
Salinity
pH
most
important
wetlands.
was
further
negatively
correlated
with
high
nitrite
concentrations.
Altogether,
this
study
existence,
driving
factors
ecosystems,
thus
providing
insights
into
ecological
niches
recently
discovered
nitrifying
consortium
contributions
nitrification
environments.
Abstract
Background
The
discovery
of
microorganisms
capable
complete
ammonia
oxidation
to
nitrate
(comammox)
has
prompted
a
paradigm
shift
in
our
understanding
nitrification,
an
essential
process
N
cycling,
hitherto
considered
require
both
oxidizing
and
nitrite
microorganisms.
This
intriguing
metabolism
is
unique
the
genus
Nitrospira
,
diverse
taxon
previously
known
only
contain
canonical
oxidizers.
Comammox
have
been
detected
environments;
however,
global
view
distribution,
abundance,
diversity
species
still
incomplete.
Results
In
this
study,
we
retrieved
55
metagenome-assembled
genomes
(MAGs)
from
newly
obtained
publicly
available
metagenomes.
Combined
with
MAGs,
constitutes
largest
genome
database
date
205
representing
132
putative
species,
most
without
cultivated
representatives.
Mapping
metagenomic
sequencing
reads
various
environments
against
enabled
analysis
distribution
habitat
preferences
species.
’s
ecological
success
evident
as
they
outnumber
present
higher
species-level
richness
than
all
examined,
except
for
marine
wastewaters
samples.
type
environment
governs
large-scale
biogeographical
signal.
We
found
that
closely
related
tend
occupy
same
habitats,
phylogenetic
signal
preference
stronger
.
eco-evolutionary
history
more
complex,
subclades
achieving
rapid
niche
divergence
via
horizontal
transfer
genes,
including
gene
encoding
hydroxylamine
oxidoreductase,
key
enzyme
nitrification.
Conclusions
Our
study
expands
genomic
inventory
genus,
exposes
oxidizers
within
wide
range
identifies
(sub)lineages
comammox
proposes
genes
involved
nitrification
linked
separation
sublineage
Nitrospira.
Global Change Biology,
Год журнала:
2023,
Номер
29(7), С. 1984 - 1997
Опубликована: Янв. 6, 2023
The
contribution
of
agriculture
to
the
sustainable
development
goals
requires
climate-smart
and
profitable
farm
innovations.
Increasing
ammonia
fertilizer
applications
meet
global
food
demands
results
in
high
agricultural
costs,
environmental
quality
deterioration,
warming,
without
a
significant
increase
crop
yield.
Here,
we
reported
that
third
microbial
oxidation
process,
complete
(comammox),
is
contributing
loss
(41.9
±
4.8%)
at
rate
3.53
0.55
mg
N
kg-1
day-1
soils
around
world.
comammox
loss,
occurring
mainly
surface
soil
profiles
(0-0.2
m),
was
equivalent
bacterial
(48.6
4.5%);
both
processes
were
significantly
more
important
than
archaeal
(9.5
3.6%).
In
contrast,
produced
less
N2
O
(0.98
0.44
μg
,
11.7
3.1%),
comparable
by
(16.4
4.4%)
but
lower
(72.0
5.1%).
efficiency
conversion
(0.02
0.01%)
evidently
(0.24
0.06%)
(0.16
0.04%)
oxidation.
increased
with
increasing
pH
values,
which
only
physicochemical
characteristic
influenced
abundance
rates.
Ammonia
dominated
oxidation,
intense
>6.5
<6.5.
Our
revealed
plays
vital
role
agroecosystems
have
been
previously
overlooked
for
long
term.
