Applied and Environmental Microbiology,
Journal Year:
2023,
Volume and Issue:
89(9)
Published: Sept. 6, 2023
Complete
ammonia
oxidizers
(comammox
Nitrospira)
are
ubiquitous
in
coastal
wetland
sediments
and
play
an
important
role
nitrification.
Our
study
examined
the
impact
of
habitat
modifications
on
comammox
Nitrospira
communities
across
tropical
subtropical
regions
southeastern
China.
Samples
were
collected
from
21
wetlands
five
provinces
where
native
mudflats
invaded
by
Spartina
alterniflora
subsequently
converted
to
aquaculture
ponds.
The
results
showed
that
abundances
mainly
influenced
sediment
grain
size
rather
than
modifications.
Compared
S.
marshes
mudflats,
pond
had
lower
diversity,
clade
A.1
abundance,
higher
A.2
abundance.
Sulfate
concentration
was
most
factor
controlling
diversity
Nitrospira.
response
community
change
varied
significantly
location,
environmental
variables
accounted
for
only
11.2%
variations
structure
all
sites.
In
three
types,
dispersal
limitation
largely
controlled
assembly
process,
indicating
stochastic
nature
these
wetlands.
IMPORTANCE
Comammox
have
recently
gained
attention
their
potential
nitrification
nitrous
oxide
(N2O)
emissions
soil
sediment.
However,
distribution
impacted
poorly
understood,
particularly
a
large
spatial
scale.
provides
novel
evidence
effects
modification
dependent
location
wetland.
We
also
found
governed
processes.
Nevertheless,
sulfate
identified
as
key
affecting
abundance
sediments.
These
findings
significant
they
advance
our
understanding
adaptation
how
future
landscape
may
Applied and Environmental Microbiology,
Journal Year:
2024,
Volume and Issue:
90(7)
Published: July 24, 2024
ABSTRACT
Nitrification
by
aquarium
biofilters
transforms
ammonia
waste
(NH
3
/NH
4
+
)
to
less
toxic
nitrate
(NO
-
via
nitrite
2
).
Prior
the
discovery
of
complete
ammonia-oxidizing
(“comammox”
or
CMX)
Nitrospira
,
previous
research
revealed
that
archaea
(AOA)
dominated
over
bacteria
(AOB)
in
freshwater
biofilters.
Here,
we
profiled
biofilter
microbial
communities
and
quantified
abundance
all
three
known
oxidizers
using
16S
rRNA
gene
sequencing
quantitative
PCR
(qPCR),
respectively.
Biofilter
water
samples
were
each
collected
from
representative
residential
commercial
saltwater
aquaria.
Distinct
associated
with
Comammox
amoA
genes
detected
38
(average
CMX
genes:
2.2
×
10
±
1.5
copies/ng)
dominant
30,
whereas
AOA
present
35
1.1
2.7
only
7
them.
The
AOB
at
relatively
low
within
3.2
1
copies
genes/ng
DNA),
except
for
highest
concentration.
For
biofilters,
differentially
abundant,
no
comammox
detected.
Additional
differential
distributions,
suggesting
niche
adaptation
based
on
chemistry
(e.g.,
ammonia,
carbonate
hardness,
alkalinity).
Network
analysis
demonstrated
positive
correlations
between
nitrifiers
heterotrophs,
metabolic
ecological
interactions
These
results
demonstrate
plays
a
previously
overlooked,
but
important
role
home
nitrification.
IMPORTANCE
is
crucial
process
converts
into
harmful
occurs
found
Our
study
currently
groups
aerobic
oxidizers.
findings
reveal
(comammox)
high
abundance,
challenging
our
understanding
We
also
highlight
salinity.
network
significant
among
other
community
members,
intricate
communities.
Overall,
this
expands
nitrification
emphasizes
highlights
value
aquaria
as
microcosms
studying
nitrifier
ecology.
Frontiers in Microbiology,
Journal Year:
2025,
Volume and Issue:
15
Published: Jan. 15, 2025
The
contrasting
response
of
AOA,
AOB,
and
comammox
Nitrospira
amoA
transcript
abundance
to
temperature,
moisture,
nitrogen
was
investigated
using
soil
microcosms.
treatments
were
selected
represent
conditions
typically
found
in
a
New
Zealand
(NZ)
dairy
farm.
AOB
dominated
all
synthetic
urine
treated
soils.
Peak
positively
correlated
with
estimated
ammonia
availability.
While
gDNA
nitrification
rate
trends
similar.
AOA
strongly
influenced
by
temperature.
At
20°C,
peak
averaged
over
1
order
magnitude
higher
than
at
8°C.
Within
the
community
member
Nitrosocosmicus
clade
ammonium
concentrations.
presence
relative
increase
an
high
environment
poses
interesting
contrast
current
scientific
opinion
NZ.
Comammox
showed
no
correlation
moisture.
This
suggests
that
previously
associations
are
more
complex
originally
thought.
Further
research
is
required
determine
drivers
moisture
environment.
Overall,
these
results
indicate
main
farm
The Science of The Total Environment,
Journal Year:
2022,
Volume and Issue:
858, P. 159961 - 159961
Published: Nov. 4, 2022
The
objectives
of
this
study
were
to
investigate
the
abundance
and
community
composition
comammox
Nitrospira
under:
(i)
pasture-based
dairy
farms
from
different
regions,
(ii)
land
uses
same
region
soil
type.
results
clearly
showed
that
most
abundant
(3.0
×
106
copies)
under
west
coast
farm
conditions,
where
they
also
significantly
more
than
canonical
ammonia
oxidisers.
This
was
true
in
Canterbury
farm.
six
investigated
pine
monoculture,
a
long
term
no
input
ecological
trial,
sheep
+
beef
Dairy,
both
irrigated
non-irrigated.
It
concluded
(2.7
copies).
Contrary
current
industry
opinion,
relatively
high
fertile
suggests
found
terrestrial
ecosystems
may
be
copiotrophic.
it
determined
use
their
non-irrigated
counterparts,
suggesting
moisture
is
key
environmental
parameter
influencing
abundance.
Comammox
positively
correlated
with
annual
rainfall,
further
supporting
theory.
Phylogenetic
analysis
detected
17
%
belonged
newly
distinguished
subclade,
clade
B.2.
remaining
83
B.1.
No
sequences
A
found.
