Communications Biology,
Journal Year:
2019,
Volume and Issue:
2(1)
Published: May 21, 2019
Abstract
Hydrogen
sulfide
(H
2
S)
plays
important
roles
in
metabolism
and
health.
Its
enzymatic
generation
from
sulfur-containing
amino
acids
(SAAs)
is
well
characterized.
However,
the
existence
of
non-enzymatic
H
S
production
SAAs,
chemical
mechanism,
its
biological
implications
remain
unclear.
Here
we
present
vitro
blood
via
a
reaction
specific
for
SAA
cysteine
serving
as
substrate
requires
coordinated
catalysis
by
Vitamin
B
6
,
pyridoxal(phosphate),
iron
under
physiological
conditions.
An
initial
cysteine-aldimine
formed
nucleophilic
attack
group
to
pyridoxal(phosphate)
aldehyde
group.
Free
or
heme-bound
drives
formation
cysteine-quinonoid,
thiol
elimination,
hydrolysis
desulfurated
aldimine
back
pyridoxal(phosphate).
The
ultimately
produces
pyruvate,
NH
3
S.
This
work
highlights
inducible
robust
select
tissues,
whereas
iron-catalyzed
contributes
underappreciated
basal
systemically
with
pathophysiological
hemolytic,
overload,
hemorrhagic
disorders.
Chemical Reviews,
Journal Year:
2017,
Volume and Issue:
118(3), P. 1253 - 1337
Published: Nov. 7, 2017
Signaling
by
H2S
is
proposed
to
occur
via
persulfidation,
a
posttranslational
modification
of
cysteine
residues
(RSH)
persulfides
(RSSH).
Persulfidation
provides
framework
for
understanding
the
physiological
and
pharmacological
effects
H2S.
Due
inherent
instability
persulfides,
their
chemistry
understudied.
In
this
review,
we
discuss
biologically
relevant
enzymatic
routes
its
production
oxidation.
We
cover
chemical
biology
probes
detecting
them.
conclude
discussing
roles
ascribed
protein
persulfidation
in
cell
signaling
pathways.
The Journals of Gerontology Series A,
Journal Year:
2017,
Volume and Issue:
73(3), P. 318 - 326
Published: Dec. 13, 2017
Abstract
Consuming
a
Mediterranean
diet
rich
in
minimally
processed
plant
foods
has
been
associated
with
reduced
risk
of
developing
multiple
chronic
diseases
and
increased
life
expectancy.
Data
from
several
randomized
clinic
trials
have
demonstrated
beneficial
effect
the
primary
secondary
prevention
cardiovascular
disease,
type
2
diabetes,
atrial
fibrillation,
breast
cancer.
The
exact
mechanism
by
which
an
adherence
to
traditional
exerts
its
favorable
effects
is
not
known.
However,
accumulating
evidence
indicates
that
five
most
important
adaptations
induced
dietary
pattern
are:
(a)
lipid-lowering
effect,
(b)
protection
against
oxidative
stress,
inflammation
platelet
aggregation,
(c)
modification
hormones
growth
factors
involved
pathogenesis
cancer,
(d)
inhibition
nutrient
sensing
pathways
specific
amino
acid
restriction,
(e)
gut
microbiota-mediated
production
metabolites
influencing
metabolic
health.
More
studies
are
needed
understand
how
single
modifications
nutrients
typical
interact
energy
intake,
expenditure,
microbiome
modulating
key
mechanisms
promote
cellular,
tissue,
organ
health
during
aging.
Nature Communications,
Journal Year:
2017,
Volume and Issue:
8(1)
Published: Oct. 23, 2017
Abstract
Cysteine
hydropersulfide
(CysSSH)
occurs
in
abundant
quantities
various
organisms,
yet
little
is
known
about
its
biosynthesis
and
physiological
functions.
Extensive
persulfide
formation
apparent
cysteine-containing
proteins
Escherichia
coli
mammalian
cells
believed
to
result
from
post-translational
processes
involving
hydrogen
sulfide-related
chemistry.
Here
we
demonstrate
effective
CysSSH
synthesis
the
substrate
l
-cysteine,
a
reaction
catalyzed
by
prokaryotic
cysteinyl-tRNA
synthetases
(CARSs).
Targeted
disruption
of
genes
encoding
mitochondrial
CARSs
mice
human
shows
that
have
crucial
role
endogenous
production
suggests
these
enzymes
serve
as
principal
cysteine
synthases
vivo.
also
catalyze
co-translational
polysulfidation
are
involved
regulation
biogenesis
bioenergetics.
Investigating
CARS-dependent
may
thus
clarify
aberrant
redox
signaling
pathophysiological
conditions,
suggest
therapeutic
targets
based
on
oxidative
stress
dysfunction.
