iScience,
Год журнала:
2022,
Номер
25(9), С. 104895 - 104895
Опубликована: Авг. 8, 2022
In
the
biological
nitrogen
cycle,
nitrite
oxidation
is
performed
by
bacteria,
of
which
Nitrospira
widespread
and
diverse.
Communities
were
collected
at
25-1500
m
depths
in
South
China
Sea.
Phylogenetic
diversity,
community
composition,
environmental
factors
investigated
using
high-throughput
sequencing
targeting
nxrB
gene
statistical
analyses.
The
composition
varied
spatially
depth.
Among
24
OTUs
with
relatively
high
abundance,
70%
unclassified
not
affiliated
known
genus,
suggesting
a
previously
unrecognized
diversity
marine
Nitrospira.
Five
genera
detected,
common
marina
was
dominant
species,
whereas
Candidatus
lenta
defluvii
dominated
shallow
habitats.
Comammox
nitrosa
discovered
ecosystem.
niche
differentiation
versatile
species
mainly
shaped
nitrate,
temperature,
DO.
Bacteria
have
important
functions
in
biogeochemical
cycles,
but
studies
on
their
function
an
ecosystem,
mangroves,
are
still
limited.
Here,
we
investigated
the
ecological
role
of
bacteria
involved
cycles
seven
representative
mangroves
southern
China.
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.
Journal of Hazardous Materials,
Год журнала:
2023,
Номер
458, С. 131813 - 131813
Опубликована: Июнь 9, 2023
Microplastics
(MPs)
are
1-5
mm
plastic
particles
that
serious
global
contaminants
distributed
throughout
marine
ecosystems.
However,
their
impact
on
intertidal
sediment
microbial
communities
is
poorly
understood.
In
this
study,
we
conducted
a
30-day
laboratory
tidal
microcosm
experiment
to
investigate
the
effects
of
MPs
communities.
Specifically,
used
biodegradable
polymers
polylactic
acid
(PLA)
and
polybutylene
succinate
(PBS),
as
well
conventional
polyethylene
terephthalate
(PET),
polycarbonate
(PC),
(PE).
Treatments
with
different
concentrations
(1-5%,
w/w)
PLA-
PE-MPs
were
also
included.
We
analyzed
taxonomic
variations
in
archaeal
bacterial
using
16S
rRNA
high-throughput
sequencing.
PLA-MPs
at
1%
(w/w)
rapidly
altered
microbiome
composition.
Total
organic
carbon
nitrite
nitrogen
key
physicochemical
factors
urease
was
major
enzyme
shaping
MP-exposed
Stochastic
processes
predominated
assembly
addition
enhanced
contribution
ecological
selections.
The
keystone
taxa
archaea
bacteria
Nitrososphaeria
Alphaproteobacteria,
respectively.
exposure
had
less
effect
functions
while
cycling
decreased
treatments.
These
findings
expanded
current
understanding
mechanism
pattern
affect
