Journal of the American Chemical Society,
Journal Year:
2021,
Volume and Issue:
143(2), P. 1107 - 1118
Published: Jan. 7, 2021
Artificial
enzymatic
systems
are
extensively
studied
to
mimic
the
structures
and
functions
of
their
natural
counterparts.
However,
there
remains
a
significant
gap
between
structural
modeling
catalytic
activity
in
these
artificial
systems.
Herein
we
report
novel
strategy
for
construction
an
binuclear
copper
monooxygenase
starting
from
Ti
metal–organic
framework
(MOF).
The
deprotonation
hydroxide
groups
on
secondary
building
units
(SBUs)
MIL-125(Ti)
(MIL
=
Matériaux
de
l'Institut
Lavoisier)
allows
metalation
SBUs
with
closely
spaced
CuI
pairs,
which
oxidized
by
molecular
O2
afford
CuII2(μ2-OH)2
cofactor
MOF-based
Ti8-Cu2.
An
mononuclear
Cu
Ti8-Cu1
was
also
prepared
comparison.
monooxygenases
were
characterized
combination
thermogravimetric
analysis,
inductively
coupled
plasma–mass
spectrometry,
X-ray
absorption
spectroscopy,
Fourier-transform
infrared
UV–vis
spectroscopy.
In
presence
coreductants,
Ti8-Cu2
exhibited
outstanding
toward
wide
range
monooxygenation
processes,
including
epoxidation,
hydroxylation,
Baeyer–Villiger
oxidation,
sulfoxidation,
turnover
numbers
up
3450.
showed
frequency
at
least
17
times
higher
than
that
Ti8-Cu1.
Density
functional
theory
calculations
revealed
activation
as
rate-limiting
step
processes.
Computational
studies
further
Cu2
sites
cooperatively
stabilized
Cu–O2
adduct
O–O
bond
cleavage
6.6
kcal/mol
smaller
free
energy
increase
Ti8-Cu1,
accounting
significantly
over
Chemical Reviews,
Journal Year:
2016,
Volume and Issue:
117(8), P. 5226 - 5333
Published: Dec. 12, 2016
Oxidative
cyclizations
are
important
transformations
that
occur
widely
during
natural
product
biosynthesis.
The
from
acyclic
precursors
to
cyclized
products
can
afford
morphed
scaffolds,
structural
rigidity,
and
biological
activities.
Some
of
the
most
dramatic
alterations
in
biosynthesis
through
oxidative
cyclization.
In
this
Review,
we
examine
different
strategies
used
by
nature
create
new
intra(inter)molecular
bonds
via
redox
chemistry.
This
Review
will
cover
both
oxidation-
reduction-enabled
cyclization
mechanisms,
with
an
emphasis
on
former.
Radical
catalyzed
P450,
nonheme
iron,
α-KG-dependent
oxygenases,
radical
SAM
enzymes
discussed
illustrate
use
molecular
oxygen
S-adenosylmethionine
forge
at
unactivated
sites
one-electron
manifolds.
Nonradical
flavin-dependent
monooxygenases
NAD(P)H-dependent
reductases
covered
show
two-electron
manifolds
initiating
reactions.
installations
epoxides
halogens
into
scaffolds
drive
subsequent
separately
as
examples
"disappearing"
reactive
handles.
Last,
rearrangement
rings
systems,
including
contractions
expansions,
be
covered.
Journal of Enzyme Inhibition and Medicinal Chemistry,
Journal Year:
2015,
Volume and Issue:
31(1), P. 1 - 13
Published: Feb. 16, 2015
Tyrosinase
plays
a
pivotal
role
in
the
synthesis
of
melanin
pigment
on
skin
utilizing
tyrosine
as
substrate.
Melanin
is
responsible
for
protection
against
harmful
ultraviolet
irradiation,
which
can
cause
significant
pathological
conditions,
such
cancers.
However,
it
also
create
esthetic
problems
when
accumulated
hyperpigmented
spots.
Various
skin-whitening
ingredients
inhibit
tyrosinase
activity
have
been
identified.
Some
them,
especially
ones
with
natural
product
origins,
possess
phenolic
moiety
and
employed
cosmetic
products.
Semi-synthetic
synthetic
inhibitors
developed
under
inspiration
yet
some
no
groups.
In
this
review,
natural,
semi-synthetic
origins
are
listed
up
their
structures,
activities
characteristics.
Further,
recent
report
adverse
effect
inhibitor
was
included
cosmetics
briefly
discussed.
Journal of Medicinal Chemistry,
Journal Year:
2018,
Volume and Issue:
61(17), P. 7395 - 7418
Published: May 15, 2018
Melanins
are
pigment
molecules
that
determine
the
skin,
eye,
and
hair
color
of
human
subject
to
its
amount,
quality,
distribution.
Melanocytes
synthesize
melanin
provide
epidermal
protection
from
various
stimuli,
such
as
harmful
ultraviolet
radiation,
through
complex
process
called
melanogenesis.
However,
serious
dermatological
problems
occur
when
there
is
excessive
production
in
different
parts
body.
These
include
freckles,
melasma,
senile
lentigo,
pigmented
acne
scars,
cancer.
Therefore,
controlling
an
important
approach
for
treatment
pigmentation
related
disorderes.
In
this
Perspective,
we
focus
on
inhibitors
melanogenesis
directly/indirectly
target
a
key
enzyme
tyrosinase
well
associated
signaling
pathways.
Environmental Science & Technology,
Journal Year:
2021,
Volume and Issue:
55(21), P. 14494 - 14514
Published: Oct. 20, 2021
The
presence
of
diverse
pollutants
in
water
has
been
threating
human
health
and
aquatic
ecosystems
on
a
global
scale.
For
more
than
century,
chemical
oxidation
using
strongly
oxidizing
species
was
one
the
most
effective
technologies
to
destruct
ensure
safe
clean
supply.
However,
removal
increasing
amount
with
higher
structural
complexity,
especially
emerging
micropollutants
trace
concentrations
complicated
matrix,
requires
excessive
dosage
oxidant
and/or
energy
input,
resulting
low
cost-effectiveness
possible
secondary
pollution.
Consequently,
it
is
practical
significance
but
scientifically
challenging
achieve
selective
interest
for
decontamination.
Currently,
there
are
variety
examples
concerning
aqueous
systems.
systematic
understanding
relationship
between
origin
selectivity
its
applicable
treatment
scenarios,
as
well
rational
design
catalyst
catalytic
oxidation,
still
lacking.
In
this
critical
review,
we
summarize
state-of-the-art
strategies
decontamination
probe
origins
selectivity,
that
is,
from
reactivity
either
oxidants
or
target
pollutants,
arising
accessibility
via
adsorption
size
exclusion,
due
interfacial
electron
transfer
process
enzymatic
oxidation.
Finally,
challenges
perspectives
briefly
outlined
stimulate
future
discussion
decontamination,
particularly
toward
application
real
scenarios.
Chemistry - A European Journal,
Journal Year:
2017,
Volume and Issue:
24(1), P. 47 - 55
Published: Oct. 20, 2017
Melanin
is
the
main
pigment
responsible
for
color
of
human
skin,
hair
and
eye.
Its
biosynthesis
requires
three
melanogenic
enzymes,
tyrosinase
(TYR),
tyrosinase-related
proteins
TYRP1
TYRP2.
The
difficulty
isolating
pure
homogeneous
from
endogenous
sources
has
hampered
their
study,
resulted
in
many
contradictory
findings
regarding
physiological
functions.
In
this
review,
we
summarize
recent
advances
on
structure
function
TYR
TYRPs
by
virtue
crystal
TYRP1,
which
first
available
a
mammalian
enzyme.
This
structure,
combined
with
structures
other
lower
eukaryotes
mutagenesis
studies
key
active
site
residues,
sheds
light
mechanism
TYRPs.
Furthermore,
TYRP1-based
homology
model
provides
high-quality
platform
to
map
analyze
albinism-related
mutations,
as
well
design
specific
antimelanogenic
compounds.
Finally,
provide
perspectives
future
structure/function
Journal of Investigative Dermatology,
Journal Year:
2018,
Volume and Issue:
138(7), P. 1601 - 1608
Published: Feb. 7, 2018
Tyrosinase
is
the
rate-limiting
enzyme
of
melanin
production
and,
accordingly,
most
prominent
target
for
inhibiting
hyperpigmentation.
Numerous
tyrosinase
inhibitors
have
been
identified,
but
those
lack
clinical
efficacy
because
they
were
identified
using
mushroom
as
target.
Therefore,
we
used
recombinant
human
to
screen
a
library
50,000
compounds
and
compared
active
screening
hits
with
well-known
whitening
ingredients.
Hydroquinone
its
derivative
arbutin
only
weakly
inhibited
half-maximal
inhibitory
concentration
(IC50)
in
millimolar
range,
kojic
acid
showed
weak
(IC50
>
500
μmol/L).
The
potent
this
resorcinyl-thiazole
derivatives,
especially
newly
Thiamidol
(Beiersdorf
AG,
Hamburg,
Germany)
(isobutylamido
thiazolyl
resorcinol),
which
had
an
IC50
1.1
μmol/L.
In
contrast,
=
108
melanocyte
cultures,
strongly
reversibly
0.9
μmol/L),
whereas
hydroquinone
irreversibly
melanogenesis
16.3
Clinically,
visibly
reduced
appearance
age
spots
within
4
weeks,
after
12
weeks
some
indistinguishable
from
normal
adjacent
skin.
full
potential
reduce
hyperpigmentation
skin
needs
be
explored
future
studies.
