Investigation of the effect of salt stress on photosynthetic electron transport pathways in the SynechocystisPCC 6803 cyanobacterium
Physiologia Plantarum,
Journal Year:
2025,
Volume and Issue:
177(1)
Published: Jan. 1, 2025
Abstract
Cyanobacteria
are
important
model
organisms
for
studying
the
process
of
photosynthesis
and
effects
environmental
stress
factors.
This
study
aimed
to
identify
inhibitory
sites
NaCl
in
whole
photosynthetic
electron
transport
Synechocysti
s
sp.
PCC
6803
WT
cells
by
using
multiple
biophysical
tools.
Exposure
various
concentrations
(200
mM
1
M)
revealed
inhibition
Photosystem
II
(PSII)
activity
at
water
oxidizing
complex
between
Q
A
B
acceptors.
In
contrast
PSII,
flow
through
I
(PSI)
was
accelerated,
indicating
enhanced
cyclic
flow.
The
oxygen‐evolving
capacity
inhibited
a
larger
extent
when
only
CO
2
final
acceptor
Calvin‐Benson‐Bassham
(CBB)
cycle
than
presence
PSII
DMBQ,
suggesting
site(s)
downstream
PSI.
Measurements
NADPH
kinetics
NaCl‐induced
light‐induced
production
as
well
retardation
consumption
both
light
initial
dark
period
after
switching
off
light.
Chlorophyll
fluorescence
kinetics,
measured
parallel
with
fluorescence,
showed
enhancement
post‐illumination
rise
up
500
NaCl,
which
however
higher
concentrations.
Our
results
show,
first
time,
that
inhibits
CBB
least
two
different
sites,
confirm
earlier
about
donor
side
Language: Английский
Novel technique for the ultra-sensitive detection of hazardous contaminants using an innovative sensor integrated with a bioreactor
Scientific Reports,
Journal Year:
2024,
Volume and Issue:
14(1)
Published: June 4, 2024
Abstract
This
study
introduces
an
evaluation
methodology
tailored
for
bioreactors,
with
the
aim
of
assessing
stress
experienced
by
algae
due
to
harmful
contaminants
released
from
antifouling
(AF)
paints.
We
present
online
monitoring
system
equipped
ultra-sensitive
sensor
that
conducts
non-invasive
measurements
algal
culture's
optical
density
and
physiological
stage
through
chlorophyll
fluorescence
signals.
By
coupling
flash-induced
fluorescence,
we
examined
dynamic
changes
in
green
microalga
Chlamydomonas
reinhardtii
when
exposed
biocides.
Over
a
24-h
observation
period,
increasing
concentrations
biocides
led
decrease
photosynthetic
activity.
Notably,
substantial
reduction
maximum
quantum
yield
primary
photochemistry
(F
V
/F
M
)
was
observed
within
first
hour
exposure.
Subsequently,
detected
partial
recovery
F
;
however,
this
remained
50%
lower
than
controls.
Integrating
advanced
submersible
decay
kinetics
offered
comprehensive
perspective
on
alterations
cells
under
exposure
coatings.
The
analysis
relaxation
revealed
significant
shortening
fast
middle
phases,
along
increase
duration
slow
phase,
coating
highest
levels
Combining
automated
culturing
measuring
methods,
approach
has
demonstrated
its
effectiveness
as
ultrasensitive
tool
physiology
cultures.
is
particularly
valuable
context
studying
microalgae
their
early
responses
various
environmental
conditions,
well
potential
develop
AF
minimal
harm
environment.
Language: Английский
Monitoring the photosynthetic activity at single-cell level in Haematococcus lacustris
Photosynthetica,
Journal Year:
2023,
Volume and Issue:
61(SPECIAL ISSUE 2023-2), P. 473 - 482
Published: Dec. 18, 2023
Haematococcus
lacustris
is
an
important
species
of
green
algae
because
it
produces
the
high-value
carotenoid
astaxanthin.
Astaxanthin
production
enhanced
by
various
stress
conditions
causing
transformation
vegetative
cells
to
red
with
high
amounts
astaxanthin,
which
plays
photoprotective
and
antioxidant
roles.
Although
intensive
research
has
been
conducted
reveal
regulation
astaxanthin
production,
photosynthetic
capacity
cell
forms
unresolved
at
single-cell
level.
In
this
work,
we
characterized
morphological
changes
Haematococcus
cells,
using
a
combination
microfluidic
tools
microscopic
chlorophyll
fluorescence
imaging.
We
found
marked
but
reversible
in
variable
signatures
upon
cells,
propose
that
activity
as
revealed
kinetics
serves
useful
phenotypic
marker
different
Haematococcus.
Language: Английский
Characterization of the Flash-Induced Fluorescence Wave Phenomenon in the Coral Endosymbiont Algae, Symbiodiniaceae
Sabit Mohammad Aslam,
No information about this author
Imre Vass,
No information about this author
Milán Szabó
No information about this author
et al.
International Journal of Molecular Sciences,
Journal Year:
2023,
Volume and Issue:
24(10), P. 8712 - 8712
Published: May 13, 2023
The
dinoflagellate
algae,
Symbiodiniaceae,
are
significant
symbiotic
partners
of
corals
due
to
their
photosynthetic
capacity.
processes
the
microalgae
consist
linear
electron
transport,
which
provides
energetic
balance
ATP
and
NADPH
production
for
CO2
fixation,
alternative
transport
pathways,
including
cyclic
flow,
ensures
elevated
requirements
under
stress
conditions.
Flash-induced
chlorophyll
fluorescence
relaxation
is
a
non-invasive
tool
assess
various
pathways.
A
special
case
relaxation,
so-called
wave
phenomenon,
was
found
be
associated
with
activity
NAD(P)H
dehydrogenase
(NDH)
in
microalgae.
We
showed
previously
that
phenomenon
existed
Symbiodiniaceae
acute
heat
microaerobic
conditions,
however,
related
remained
unknown.
In
this
work,
using
inhibitors,
we
show
(i)
has
crucial
role
formation
wave,
(ii)
inhibition
donor
side
Photosystem
II
did
not
induce
whereas
Calvin-Benson
cycle
accelerated
it,
(iii)
operation
type
NDH
(NDH-2).
therefore
propose
an
important
marker
regulation
Symbiodiniaceae.
Language: Английский