bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2023,
Номер
unknown
Опубликована: Июль 3, 2023
Abstract
Giant
unilamellar
vesicles
(GUVs)
are
micrometer-scale
lipid
assemblies
that
emulate
key
characteristics
of
biological
cell
membranes.
GUVs
can
be
obtained
when
solid-supported
thin
films
lipids
hydrated
in
aqueous
solutions.
However,
a
comprehensive
understanding
their
assembly
dynamics
has
been
lacking,
impeding
mechanistic
insights.
Here,
we
report
the
time
dependence
distribution
sizes
and
molar
yield
through
novel
‘stopped-time’
technique.
We
compare
three
commonly
used
techniques,
PAPYRUS
(Paper-Abetted
amPhiphile
hYdRation
aqUeous
Solutions)
gentle
hydration,
electroformation.
demonstrate
all
techniques
show
sigmoidal
curves.
Yields
increase
monotonically
before
reaching
plateau,
with
surprisingly
high
yields
60
seconds
after
hydration.
Gentle
hydration
shows
limited
evolution
contrast
to
Exploration
bud
on
surfaces
uncovers
emergence,
diameter
growth,
merging
phenomena.
To
provide
explanation
our
observations,
employ
thermodynamic
budding
model.
This
work
expands
GUV
offers
fundamental
insights
into
underlying
principles
governing
this
process.
Giant
unilamellar
vesicles
(GUVs)
integrated
with
membrane
proteins
(proteo-GUVs)
are
attractive
tools
for
visualizing
protein
functions
such
as
enzyme
reactions
and
molecular
transportation.
In
the
dehydration–rehydration
method,
one
of
methods
used
to
form
proteo-GUVs,
they
formed
by
using
a
dried
film
containing
phospholipids
through
rehydration
an
alternating
current
electric
field
supporting
gel.
However,
these
make
it
difficult
proteo-GUVs
under
physiological
salt
concentration
charged
phospholipid
conditions
or
carry
risk
gel
contamination
lipid
membranes.
Therefore,
may
be
harmful
proteins.
Here,
we
propose
method
formation
concentrations
negatively
that
do
not
require
To
investigate
transport
modified
outer
G
(OmpG),
OmpG-giant
OmpG-large
(LUVs)
were
formed.
The
structure
function
different
mutants
reconstituted
into
LUVs
evaluated
circular
dichroism
spectroscopy
electrophysiological
measurements.
addition,
OmpG
in
GUVs
was
monitoring
Ca2+
influx
fluorescent
molecule
leakage
from
nanopores.
We
found
amount
nanopores
depended
on
pore
size
OmpG.
Our
forming
can
applied
functional
evaluation
β-barrel
porin
biological
sensors
porin.
Research Square (Research Square),
Год журнала:
2024,
Номер
unknown
Опубликована: Май 29, 2024
Abstract
The
study
of
cell
membrane
structures
under
microgravity
is
crucial
for
understanding
the
inherent
physiological
and
adaptive
mechanisms
relevant
to
overcoming
challenges
in
human
space
travel
gaining
deeper
insight
into
membrane-protein
interactions
at
reduced
gravity.
However,
dynamics
conditions
have
not
unraveled
yet.
Moreover,
complexity
cells
poses
significant
when
investigating
effects
on
individual
components,
including
membranes.
Giant
Unilamellar
Vesicles
(GUVs)
serve
as
valuable
cell-mimicking
models
act
artificial
cells,
providing
insights
biophysics
architecture.
Herein,
we
elucidated
simulated
conditions.
GUVs
were
synthesized
size
range
20
±
2.1
µm
examined
their
morphological
changes
using
a
random
positioning
machine.
We
observed
that
well-defined
spherical
transfigured
deformed
elongated
fluidity
increased
sevenfold
compared
normal
gravity
48
h.
It
also
noted
there
reduction
microviscosity.
shed
light
mechanics
contributes
broader
responses
its
implications
exploration
biomedical
applications.
Biophysical Journal,
Год журнала:
2024,
Номер
123(18), С. 3267 - 3274
Опубликована: Июль 26, 2024
Proton
transport
across
lipid
membranes
is
one
of
the
most
fundamental
reactions
that
make
up
living
organisms.
In
vitro,
however,
study
proton
can
be
very
challenging
due
to
limitations
imposed
by
concentrations,
compartment
size,
and
unstirred
layers
as
well
buffer
exchange
capacity.
this
study,
we
have
developed
a
permeation
assay
based
on
microfluidic
trapping
giant
vesicles
enclosing
pH-sensitive
dye
pyranine
address
some
these
challenges.
Time-resolved
fluorescence
imaging
upon
rapid
pH
shift
enabled
us
investigate
facilitated
H+
mediated
either
channel
or
carrier.
Specifically,
compared
rates
function
different
gradients
gramicidin
D
carrier
carbonyl
cyanide-m-chlorophenyl
hydrazone.
Our
results
demonstrate
efficacy
in
monitoring
distinguishing
between
channel-like
carrier-like
mechanism.
This
groundbreaking
result
elucidate
enigmatic
mode
mechanism
recently
discovered
natural
fibupeptide
lugdunin.
ACS Omega,
Год журнала:
2024,
Номер
9(46), С. 46615 - 46626
Опубликована: Ноя. 7, 2024
We
demonstrate
rapid
membrane
mixing
between
GUVs
of
pure
lipid
compositions
and
vesicles
(MVs)
isolated
from
the
plasma
Vero
cells,
resulting
in
transfer
native
lipids
proteins
to
GUVs.
The
steps
involved
are
docking
followed
by
fusion.
show
that
positively
charged
essential
for
docking,
components
MVs
drive
interleaflet
lateral
asymmetry
a
change
tension
upon
trigger
invagination.
detected
outward
inward
invagination
sites
at
rim
within
10-40
min
mixing.
extent
invaginations
depends
on
cholesterol
sphingomyelin
(SM)
contents
Cholesterol
content
above
critical
concentration
disfavors
invaginations,
SM
is
an
molecular
factor
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2023,
Номер
unknown
Опубликована: Июль 3, 2023
Abstract
Giant
unilamellar
vesicles
(GUVs)
are
micrometer-scale
lipid
assemblies
that
emulate
key
characteristics
of
biological
cell
membranes.
GUVs
can
be
obtained
when
solid-supported
thin
films
lipids
hydrated
in
aqueous
solutions.
However,
a
comprehensive
understanding
their
assembly
dynamics
has
been
lacking,
impeding
mechanistic
insights.
Here,
we
report
the
time
dependence
distribution
sizes
and
molar
yield
through
novel
‘stopped-time’
technique.
We
compare
three
commonly
used
techniques,
PAPYRUS
(Paper-Abetted
amPhiphile
hYdRation
aqUeous
Solutions)
gentle
hydration,
electroformation.
demonstrate
all
techniques
show
sigmoidal
curves.
Yields
increase
monotonically
before
reaching
plateau,
with
surprisingly
high
yields
60
seconds
after
hydration.
Gentle
hydration
shows
limited
evolution
contrast
to
Exploration
bud
on
surfaces
uncovers
emergence,
diameter
growth,
merging
phenomena.
To
provide
explanation
our
observations,
employ
thermodynamic
budding
model.
This
work
expands
GUV
offers
fundamental
insights
into
underlying
principles
governing
this
process.
