Nature,
Journal Year:
2023,
Volume and Issue:
623(7989), P. 1001 - 1008
Published: Nov. 15, 2023
Cyclic
oligonucleotide-based
antiphage
signalling
systems
(CBASS)
protect
prokaryotes
from
viral
(phage)
attack
through
the
production
of
cyclic
oligonucleotides,
which
activate
effector
proteins
that
trigger
death
infected
host1,2.
How
bacterial
cyclases
recognize
phage
infection
is
not
known.
Here
we
show
staphylococcal
phages
produce
a
structured
RNA
transcribed
terminase
subunit
genes,
termed
CBASS-activating
bacteriophage
(cabRNA),
binds
to
positively
charged
surface
CdnE03
cyclase
and
promotes
synthesis
dinucleotide
cGAMP
CBASS
immune
response.
Phages
escape
defence
harbour
mutations
lead
generation
longer
form
cabRNA
cannot
CdnE03.
As
mammalian
OAS1
also
double-stranded
during
interferon
response,
our
results
reveal
conserved
mechanism
for
activation
innate
antiviral
pathways.
Nature,
Journal Year:
2022,
Volume and Issue:
612(7938), P. 132 - 140
Published: Nov. 16, 2022
Abstract
Bacteria
have
evolved
diverse
immunity
mechanisms
to
protect
themselves
against
the
constant
onslaught
of
bacteriophages
1–3
.
Similar
how
eukaryotic
innate
immune
systems
sense
foreign
invaders
through
pathogen-associated
molecular
patterns
4
(PAMPs),
many
bacterial
that
respond
bacteriophage
infection
require
phage-specific
triggers
be
activated.
However,
identities
such
and
sensing
remain
largely
unknown.
Here
we
identify
investigate
anti-phage
function
CapRel
SJ46
,
a
fused
toxin–antitoxin
system
protects
Escherichia
coli
phages.
Using
genetic,
biochemical
structural
analyses,
demonstrate
C-terminal
domain
regulates
toxic
N-terminal
region,
serving
as
both
antitoxin
phage
sensor.
Following
by
certain
phages,
newly
synthesized
major
capsid
protein
binds
directly
relieve
autoinhibition,
enabling
toxin
pyrophosphorylate
tRNAs,
which
blocks
translation
restrict
viral
infection.
Collectively,
our
results
reveal
mechanism
senses
conserved,
essential
component
suggesting
PAMP-like
model
for
toxin–antitoxin-mediated
in
bacteria.
We
provide
evidence
CapRels
their
phage-encoded
are
engaged
‘Red
Queen
conflict’
5
revealing
new
front
intense
coevolutionary
battle
between
phages
Given
proteins
some
viruses
known
stimulate
signalling
mammalian
hosts
6–10
deeply
conserved
facet
immunity.
Cell,
Journal Year:
2023,
Volume and Issue:
186(4), P. 864 - 876.e21
Published: Feb. 1, 2023
A
fundamental
strategy
of
eukaryotic
antiviral
immunity
involves
the
cGAS
enzyme,
which
synthesizes
2′,3′-cGAMP
and
activates
effector
STING.
Diverse
bacteria
contain
cGAS-like
enzymes
that
produce
cyclic
oligonucleotides
induce
anti-phage
activity,
known
as
CBASS.
However,
this
activity
has
only
been
demonstrated
through
heterologous
expression.
Whether
harboring
CBASS
antagonize
co-evolve
with
phages
is
unknown.
Here,
we
identified
an
endogenous
enzyme
in
Pseudomonas
aeruginosa
generates
3′,3′-cGAMP
during
phage
infection,
signals
to
a
phospholipase
effector,
limits
replication.
In
response,
express
anti-CBASS
protein
("Acb2")
forms
hexamer
three
molecules
reduces
activity.
Acb2
also
binds
produced
by
other
bacterial
(3',3'-cUU/UA/UG/AA)
mammalian
(2′,3′-cGAMP),
suggesting
broad
inhibition
cGAS-based
immunity.
Upon
deletion,
blocks
lytic
replication
lysogenic
induction,
but
rare
evade
major
capsid
gene
mutations.
Altogether,
demonstrate
function
strategies
evasion.
Cell,
Journal Year:
2024,
Volume and Issue:
187(9), P. 2095 - 2116
Published: April 1, 2024
Plant
diseases
cause
famines,
drive
human
migration,
and
present
challenges
to
agricultural
sustainability
as
pathogen
ranges
shift
under
climate
change.
breeders
discovered
Mendelian
genetic
loci
conferring
disease
resistance
specific
isolates
over
100
years
ago.
Subsequent
breeding
for
underpins
modern
agriculture
and,
along
with
the
emergence
focus
on
model
plants
genetics
genomics
research,
has
provided
rich
resources
molecular
biological
exploration
last
50
years.
These
studies
led
identification
of
extracellular
intracellular
receptors
that
convert
recognition
microbe-encoded
patterns
or
pathogen-delivered
virulence
effectors
into
defense
activation.
receptor
systems,
downstream
responses,
define
plant
immune
systems
have
evolved
since
migration
land
∼500
million
Our
current
understanding
provides
platform
development
rational
enhancement
control
many
continue
plague
crop
production.
Cell Reports,
Journal Year:
2023,
Volume and Issue:
42(7), P. 112672 - 112672
Published: June 21, 2023
Prokaryotic
adaptation
is
strongly
influenced
by
the
horizontal
acquisition
of
beneficial
traits
via
mobile
genetic
elements
(MGEs),
such
as
viruses/bacteriophages
and
plasmids.
However,
MGEs
can
also
impose
a
fitness
cost
due
to
their
often
parasitic
nature
differing
evolutionary
trajectories.
In
response,
prokaryotes
have
evolved
diverse
immune
mechanisms
against
MGEs.
Recently,
our
understanding
abundance
diversity
prokaryotic
systems
has
greatly
expanded.
These
defense
degrade
invading
material,
inhibit
genome
replication,
or
trigger
abortive
infection,
leading
population
protection.
this
review,
we
highlight
these
strategies,
focusing
on
most
recent
discoveries.
The
study
defenses
not
only
sheds
light
microbial
evolution
but
uncovers
novel
enzymatic
activities
with
promising
biotechnological
applications.
