Analytical Chemistry,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 10, 2025
Cross-linking
and
covalent
labeling
are
common
tools
for
protein
structural
elucidation
by
mass
spectrometry.
However,
despite
the
importance
of
electrostatic
interactions
in
proteins,
there
not
many
probing
both
acids
amines.
Therefore,
we
introduce
novel
solution-phase
amine-to-acid
cross-linkers
single
reagent
amine
acid
labels
utilizing
carbodiimide
chemistry.
sites
were
determined
using
top-down
enzymatic
digestion
approaches.
Ubiquitin
was
chosen
as
a
model
isotopically
labeled
13C-15N-glycine
cross-linking/covalent
glycyl-l-proline
with
spectrometry
proof
concept.
Alpha
synuclein,
an
intrinsically
disordered
that
plays
role
multiple
neurological
disorders,
also
cross-linked/covalent
these
methods/reagents.
We
expect
characterization
techniques
will
play
gaining
insight
into
functionally
pathologically
important
tendencies
proteins.
International Journal of Biological Macromolecules,
Journal Year:
2024,
Volume and Issue:
263, P. 129858 - 129858
Published: Feb. 29, 2024
Tissue
engineering
(TE)
demands
scaffolds
that
have
the
necessary
resistance
to
withstand
mechanical
stresses
once
implanted
in
our
body,
as
well
excellent
biocompatibility.
Hydrogels
are
postulated
interesting
materials
for
this
purpose,
especially
those
made
from
biopolymers.
In
study,
microstructure
and
rheological
performance,
functional
biological
properties
of
chitosan
collagen
hydrogels
(CH/CG)
crosslinked
with
different
coupling
agents,
both
natural
such
d-Fructose
(F),
genipin
(G)
transglutaminase
(T)
synthetic,
using
a
combination
1-ethyl-3-(3-dimethylaminopropyl)carbodiimide
hydrochloride
N-hydroxysuccinimide
(EDC/NHS)
will
be
assessed.
FTIR
tests
were
carried
out
determine
if
proposed
crosslinking
reactions
each
agent
occurred
expected,
obtaining
positive
results
aspect.
Regarding
characterization
system,
two
main
trends
observed,
which
it
could
established
G
EDC-NHS
turned
more
effective
beneficial
than
other
producing
significant
improvements
respect
base
CH/CG
hydrogel.
addition,
vitro
demonstrated
potential
application
TE
these
systems,
G,
T
EDC-NHS.
International Journal of Molecular Sciences,
Journal Year:
2024,
Volume and Issue:
25(14), P. 7839 - 7839
Published: July 17, 2024
Adding
carbonyl
groups
into
the
hydrogel
matrix
improves
stability
and
biocompatibility
of
hydrogels,
making
them
suitable
for
different
biomedical
applications.
In
this
review
article,
we
will
discuss
use
hydrogels
based
on
polysaccharides
modified
by
oxidation,
with
particular
attention
paid
to
introduction
groups.
These
have
been
developed
several
applications
in
tissue
engineering,
drug
delivery,
wound
healing.
The
article
discusses
mechanism
which
oxidized
can
introduce
groups,
leading
development
through
cross-linking
proteins.
tunable
mechanical
properties
improved
biocompatibility.
Hydrogels
dynamic
that
make
promising
biomaterials
various
This
paper
comprehensively
analyzes
cross-linked
proteins
derived
from
polysaccharides,
including
microparticles,
nanoparticles,
films.
these
healing
are
also
discussed.
Angewandte Chemie International Edition,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Jan. 9, 2025
Abstract
Therapeutic
proteins
are
commonly
conjugated
with
polymers
to
modulate
their
pharmacokinetics
but
often
lack
a
description
of
the
polymer‐protein
interaction.
We
deployed
limited
proteolysis
mass
spectrometry
(LiP‐MS)
reveal
interaction
polyethylene
glycol
(PEG)
and
PEG
alternative
interferon‐α2a
(IFN).
Target
conjugates
were
digested
specific
protease
trypsin
“heavy”
15
N‐IFN
wild
type
(IFN‐WT)
for
time‐resolved
quantification
cleavage
dynamics.
Interactions
between
IFN‐α2a
its
high‐affinity
receptor
detailed
by
LiP‐MS.
Then,
10
kDa
PEG,
linear
polyglycerol
(LPG),
poly(2‐oxazoline)
(POX)
two
different
cyclooctyne
linkers
(BCN/DBCO)
used
site‐specific
bioconjugation
azide
functionalized
IFN‐α2a.
Tryptic
events
at
each
site
in
structural
environments
(loops/helices)
compared.
LPG
similar,
POX
showed
reduced
profile
surface.
All‐atom
molecular
dynamics
simulations
IFN‐DBCO‐polymer
revealed
distinct
transient
(below
50
ns)
protein‐interaction
profiles
LPG,
POX.
Cleavage
IFN‐polymer
from
BCN
handle
homogeneous,
pointing
more
conserved
IFN
structure
than
DBCO‐polymer
conjugates.
In
summary,
LiP‐MS
enhances
understanding
interactions,
which
may
be
extended
other
bioconjugate
types.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2025,
Volume and Issue:
unknown
Published: Feb. 26, 2025
Phosphorylation
of
serine
129
(pS129)
in
the
intrinsically
disordered
protein
alpha
synuclein
has
long
been
associated
with
neurodegenerative
disease.
In
past
several
years,
functional
relevance
pS219
uncovered
by
electrophysiology,
immunoprecipitation,
and
proteomics
as
intricately
connected
neurotransmitter
release
synaptic
vesicle
(SV)
cycling.
Unexpectedly,
binding
to
SNARE
complex
proteins
VAMP-2
synapsin
only
occurs
phosphorylation-competent
synuclein.
The
domain
shown
be
residues
96-110,
which
does
not
include
phosphorylated
residue,
hinting
at
allosteric
regulation
protein-protein
interactions
pS129.
Within
this
study,
cross-linking,
covalent
labeling,
collision
induced
unfolding
pS129
-
well
an
additional
encountered
form
brain,
oxidized-M1,
M5,
M116,
M127
are
studied
utilizing
tandem
mass
spectrometry.
Collision
gives
a
fingerprint
structures'
relative
compactness
stabilities
various
conformations.
Covalent
labeling
identifies
solvent
accessible
reveals
hydrophobicity
(or
hydrophilicity)
their
microenvironment,
while
cross-linking
maps
proximity
residue
pairs.
combination
unfolding,
show
unequivocally
that
phosphorylated-S129
results
more
stable,
compact
form.
Our
provide
evidence
extensively
folded
amphipathic
region
interacts
strongly
domain.
phosphorylation-induced
folding
likely
tunes
other
SVs
membranes.
European Polymer Journal,
Journal Year:
2024,
Volume and Issue:
205, P. 112739 - 112739
Published: Jan. 6, 2024
We
have
synthesized
and
characterized
a
collagen-hyaluronic
acid
hybrid
network.
The
aim
was
to
create
hydrogel
mimicking
the
extracellular
matrix
of
adipose
tissue,
primarily
for
use
in
vitro
studies
protein
drug
transport
subcutaneous
interstitial
space.
network
created
by
covalently
crosslinking
methacryloyl-functionalized
collagen
type
I
thiol-functionalized
hyaluronic
means
thiol-Michael
thiol-ene
photo-click
reaction.
degree
modification
corresponded
74
%
lysine
arginine
groups
on
collagen,
16
29
carboxylate
acid,
as
determined
with
1H
NMR.
Circular
dichroism
measurements
showed
that
triple
helix
modified
remained
intact.
Oscillatory
shear
rheology
tests
hydrated
networks
displayed
viscoelastic
properties
characteristic
hydrogels.
storage
modulus,
measured
at
1
Hz
frequency
linear
range
(<
5%),
varied
controllable
way
between
1.5
4
MPa
depending
concentration
collagen-to-hyaluronic
ratio.
hydrogels
had
lower
content
(0.6
-1.2
wt%)
but
similar
modulus
low
strain
rates
tissue
were
penetrable
albumin
lysozyme.
results
show
are
promising
model
systems
investigations
transport.
