The
objective
of
this
study
was
to
evaluate
the
degradation
efficiency
n-alkanes
by
a
mixture
two
Gram-positive
strains
and
one
Gram-negative
strain.
methodology
consisted
in
adapting
an
inoculum
bilge
water,
aqueous
solution
enriched
with
petroleum
diesel,
nutrients,
air
for
15
days
at
22°C.
Then,
03
indigenous
were
isolated
identified,
bacteria
mixed
strain
separated.
Each
group
inoculated
separately
into
aerated
reactors
containing
water
7
days.
Finally,
$\mathrm{C}_{5}-\mathrm{C}_{10},
\mathrm{C}_{10}-\mathrm{C}_{28}$,
$\mathrm{C}_{25}-\mathrm{C}_{40}$
fractions
quantified
gas
chromatography-FID
calculate
removal
achieved.
results
showed
presence
Rhodococcus
spp.,
Micrococcus
Pseudomona
aeruginosa.
These
produced
emulsions
each
treatment.
aeruginosa
removed
91.9%
short
chains
$(\mathrm{C}_{5-}\mathrm{C}_{10})$
86%
long
$(\mathrm{C}_{10}-\mathrm{C}_{40})$.
While
Actinobacteria
increased
from
55.3%
$(\mathrm{C}_{5}-\mathrm{C}_{10})$
65%
This
shows
potential
these
remove
Environmental Science and Pollution Research,
Год журнала:
2024,
Номер
31(21), С. 30867 - 30885
Опубликована: Апрель 15, 2024
Escalating
oil
consumption
has
resulted
in
an
increase
accidental
spills
of
petroleum
hydrocarbons,
causing
severe
environmental
degradation,
notably
vulnerable
regions
like
the
Niger
Delta.
Complex
mixture
these
hydrocarbons
particularly
long-chain
alkanes
presents
unique
challenges
restoration
polluted
environment
due
to
their
chemical
properties.
This
study
aimed
investigate
hydrocarbon-degrading
bacterial
communities
within
long-term
chronically
soil
Ogoniland,
by
utilizing
both
traditional
cultivation
methods
and
modern
culture-independent
techniques.
Results
revealed
that
surface-polluted
(SPS)
subsurface
(SPSS)
exhibit
significantly
higher
total
organic
carbon
(TOC)
ranging
from
5.64
5.06%
(TPH)
levels
36,775
ppm
14,087
ppm,
compared
unpolluted
(UPS)
with
1.97%
TOC
479
TPH,
respectively.
Analysis
chain
lengths
reveals
prevalence
longer-chain
(C20-28)
surface
soil.
Culture-dependent
methods,
crude
enrichment
(COE)
paraffin
wax
(PWE),
yield
47
isolates
subjected
a
alkane
degradation
assay.
Twelve
strains
demonstrate
significant
abilities
across
all
enriched
media.
Three
members,
namely
Pseudomonas
sp.
(almA),
Marinomonas
Alteromonas
(ladA),
genes
responsible
for
demonstrating
efficiency
between
50
80%.
Culture-independent
analysis
SPS
samples
greater
species
richness
diversity
SPSS
samples.
Proteobacteria
dominates
as
phylum
sample
types,
22.23
82.61%,
Firmicutes
(0.2-2.22%),
Actinobacteria
(0.4-3.02%),
Acidobacteria
(0.1-3.53%)
also
prevalent.
Bacterial
profiles
at
genus
level
distinct
variations
among
populations
comprising
number
hydrocarbon
degraders
functional
predictions
highlight
presence
potential
catabolic
(nahAa,
adh2,
cpnA)
However,
culture-dependent
only
captured
few
dominant
members
found
analysis,
implying
more
specialized
media
or
environments
are
needed
isolate
members.
The
findings
this
contribute
valuable
information
ecological
biotechnological
aspects,
aiding
development
effective
bioremediation
applications
restoring
oil-contaminated
environments.
International Journal of Molecular Sciences,
Год журнала:
2025,
Номер
26(4), С. 1713 - 1713
Опубликована: Фев. 17, 2025
Alkane-oxidizing
bacteria
play
a
crucial
role
in
the
global
carbon
cycle.
Rhodococcus
species
are
well-known
hydrocarbon
degraders,
distinguished
by
harboring
of
multiple
homologs
AlkB
family
alkane
monooxygenases.
Although
different
types
rhodococcal
AlkBs
have
been
described,
overall
picture
their
diversity
remains
unclear,
leaving
gaps
current
classification.
We
conducted
phylogenetic
analysis
all
identified
(sensu
lato)
and
examined
genomic
context
corresponding
genes.
The
sequence
clustering
was
well
aligned
with
neighborhoods,
allowing
both
features
to
be
used
as
criteria
for
proposing
that
form
distinct
groups
characteristic
contexts.
Our
approach
allowed
us
revise
classification
previously
described
AlkBs,
identifying
eight
on
basis,
propose
three
new
ones.
Alkane
monooxygenases
whose
genes
co-localized
rubredoxin
can
considered
generalized
AlkBR
type,
most
common
among
Rhodococcus.
In
AlkB0
which
is
paralog
AlkBR,
violations
conservativity
known
monooxygenase
signature
motifs
were
found.
findings
provide
more
consistent
framework
prevents
over-reporting
"novel"
contributes
deeper
understanding
diversity.
Journal of Bacteriology,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 11, 2025
ABSTRACT
There
is
a
demand
and
widespread
interest
in
evaluating
microbial
community
structures
metabolic
processes
hydrocarbon
environments.
The
current
work
aims
to
detect
subgroups
(phenotypic
subsets)
their
processes,
such
as
substrate
specificity
expression
of
niche-associated
genes.
In
this
study,
we
were
able
discriminate
different
cell
types
real
time
from
complex
sample
matrix
allow
the
detection
live,
dead,
injured
populations
jet
fuels.
We
found
that
alkB1
alkB2
genes
induced
growth-dependent
manner
induction
started
before
.
This
indicates
an
early
response
Pseudomonas
aeruginosa
cells’
exposure
alkanes,
cells
activate
gene
induction.
Deletion
completely
inhibited
P.
ATCC
33988
growth
fuel,
suggesting
two
alkane
monooxygenases
are
responsible
for
degradation
alkanes
fuel.
Interestingly,
AlkB2
has
broader
(
n
-C8
-n
-C16)
range
compared
AlkB1
-C12-
-C16).
data
indicate
utilization
pathways
can
coexist
33988,
they
differentially
expressed
-C6
-n-
C16
study
provided
additional
information
on
heterogeneity
phenotypic
diversity
within
same
species
after
hydrocarbons.
advances
our
understanding
provides
new
insight
into
metabolism
IMPORTANCE
Alkane
allows
natural
breakdown
hydrocarbons
crude
oil,
which
significantly
contribute
environmental
remediation.
process
microbes
not
well
understood.
originally
isolated
fuel
tank,
degrades
effectively
outcompetes
type
strain
PAO1.
differential
monooxygenase
relative
importance
these
degradation.
subsets
genotype,
influenced
by
stress.
Overall,
research
conducted
contributes
knowledge
about
structure
