Langmuir,
Journal Year:
2024,
Volume and Issue:
40(49), P. 25822 - 25833
Published: Nov. 22, 2024
We
report
an
instantaneous
room-temperature
phase
separation
of
1
mM
bovine
serum
albumin
solution
in
the
presence
(20%
acetic
acid+0.2
M
NaCl),
a
routinely
used
food
preservative;
opaque
liquid-like
(L)
coexists
equilibrium
with
granular
gel
like
(G).
Interestingly,
neither
20%
acid
nor
0.2
NaCl
individually
induces
such
separation.
Field
emission
scanning
electron
microscopy
(FESEM)
and
high-resolution
transmission
(HRTEM)
imaging
show
aggregated
proteins
to
be
dispersed
upper
phase,
while
lower
is
composed
cross-linked
fibrils
(hydrogels).
Mid-IR
FTIR,
Raman
scattering,
circular
dichroism
(CD)
experiments
reveal
significant
increase
β-sheet
content
BSA,
which
confirms
formation
amyloids
excipient.
Both
L
G
phases
undergo
distinct
visual
microscopic
changes
upon
incubation
at
25
80
°C.
It
evident
that
added
salt
plays
pivotal
role
bringing
about
this
otherwise
unique
behavior.
divulge
explicit
ion
associated
hydration
using
THz-FTIR
measurements
1.5–16.7
THz
(50–550
cm–1)
frequency
window.
Systematic
alteration
ion-induced
THz-active
mode
water
envisions
key
ions
shaping
various
phases.
Our
study
depicts
intriguing
observation
severe
amyloidosis
BSA
addition
preservative,
even
room
temperature,
expected
add
new
insight
into
amyloid
research.
Considering
increasing
number
individuals
suffering
from
several
neurodegenerative
disorders
(Alzheimer's,
Parkinson's,
type-2
diabetes,
obesity,
cancer,
etc.),
leads
caution
toward
critically
revisiting
usage
known
preservatives.
The Journal of Physical Chemistry Letters,
Journal Year:
2024,
Volume and Issue:
15(15), P. 4047 - 4055
Published: April 5, 2024
Liquid–liquid
phase
separation
(LLPS)
plays
a
key
role
in
the
compartmentalization
of
cells
via
formation
biomolecular
condensates.
Here,
we
combined
atomistic
molecular
dynamics
(MD)
simulations
and
terahertz
(THz)
spectroscopy
to
determine
solvent
entropy
contribution
condensates
human
eye
lens
protein
γD-Crystallin.
The
MD
reveal
an
tug-of-war
between
water
molecules
that
are
released
from
droplets
those
retained
within
condensates,
two
categories
were
also
assigned
spectroscopically.
A
recently
developed
THz-calorimetry
method
enables
quantitative
comparison
experimental
computational
changes
molecules.
strong
correlation
mutually
validates
approaches
opens
way
detailed
atomic-level
understanding
different
driving
forces
underlying
LLPS.
The Journal of Physical Chemistry B,
Journal Year:
2024,
Volume and Issue:
128(15), P. 3720 - 3731
Published: April 8, 2024
Cryoprotectants
play
a
crucial
role
in
preserving
biological
material,
ensuring
their
viability
during
storage
and
facilitating
applications
such
as
the
conservation
of
medical
compounds,
tissues,
organs
for
transplantation.
However,
precise
mechanism
by
which
cryoprotectants
modulate
thermodynamic
properties
water
to
impede
formation
growth
ice
crystals,
thus
preventing
long-term
damage,
remains
elusive.
This
is
evident
use
empirically
optimized
recipes
mixtures
that
typically
contain
DMSO,
glycerol,
various
sugar
constituents.
Here,
we
terahertz
calorimetry,
Overhauser
nuclear
polarization,
molecular
dynamics
simulations
show
DMSO
exhibits
robust
structuring
effect
on
around
its
methyl
groups,
reaching
maximum
at
mole
fraction
XDMSO
=
0.33.
In
contrast,
glycerol
exerts
smaller
water-structuring
effect,
even
higher
concentrations
(Scheme
1).
These
results
potentially
suggest
wrapped
DMSO's
group,
can
be
evicted
upon
ligand
binding,
may
render
more
surface-active
cryoprotectant
than
while
participate
viscogen
acts
entire
sample.
findings
shed
light
intricacies
solvation
behavior
have
significant
implications
optimizing
cryopreservation
protocols.
Chemical Science,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Jan. 1, 2025
Protein
condensates
as
membrane-less
compartments
play
a
pivotal
role
in
cellular
processes.
The
stabilization
of
protein
condensation
can
be
tuned
using
cosolutes
which
directly
impact
biological
function.
In
this
study,
we
report
the
result
rigorous
study
influence
changes
on
hydration
entropy
and
enthalpy
upon
condensate
formation,
by
means
THz-calorimetry.
Our
results
unveil
quantitative
insights
into
fine
tuning
free
energy
imbalance,
via
hydrophobic/entropic
hydrophilic/enthalpic
cosolute-mediated
or
destabilization
condensates.
These
shed
new
light
regulatory
potential
co-solutes
within
cells,
to
tune
Liquid-Liquid
Phase
Separation
(LLPS).
Furthermore,
demonstrate
transferability
underlying
molecular
concepts
cosolute
addition
two
fundamental
processes:
folding
denaturation.
This
provides
blueprint
for
controlled
modulating
LLPS
additions,
with
promising
implications
both
medical
applications.
