Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
64(2)
Published: Aug. 17, 2024
Biomolecular
machines
autonomously
convert
energy
into
functions,
driving
systems
away
from
thermodynamic
equilibrium.
This
conversion
is
achieved
by
leveraging
complex,
kinetically
asymmetric
chemical
reaction
networks
that
are
challenging
to
characterize
precisely.
In
contrast,
all
known
synthetic
molecular
in
which
kinetic
asymmetry
has
been
quantified
well
described
simple
single-cycle
networks.
Here,
we
report
on
a
unique
light-driven
[2]rotaxane
enables
the
autonomous
operation
of
machine
with
multi-cycle
network.
Unlike
prior
systems,
present
one
exploits
photoactive
macrocycle,
features
different
photoreactivity
depending
binding
sites
at
it
resides.
Furthermore,
E
Z
isomerization
reverses
relative
affinity
macrocycle
for
two
axle,
resulting
Building
most
recent
theoretical
advancements,
this
work
quantifies
network
first
time.
Our
findings
represent
simplest
rotaxane
capable
shuttling
developed
so
far
and
offer
general
strategy
generate
quantify
beyond
systems.
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(26), P. 14169 - 14183
Published: June 21, 2023
All
chemists
are
familiar
with
the
idea
that,
at
equilibrium
steady
state,
relative
concentrations
of
species
present
in
a
system
predicted
by
corresponding
constants,
which
related
to
free
energy
differences
between
components.
There
is
also
no
net
flux
species,
matter
how
complicated
reaction
network.
Achieving
and
harnessing
non-equilibrium
states,
coupling
network
second
spontaneous
chemical
process,
has
been
subject
work
several
disciplines,
including
operation
molecular
motors,
assembly
supramolecular
materials,
strategies
enantioselective
catalysis.
We
juxtapose
these
linked
fields
highlight
their
common
features
challenges
as
well
some
misconceptions
that
may
be
serving
stymie
progress.
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
63(23)
Published: April 3, 2024
Abstract
Over
the
last
two
decades
ratchet
mechanisms
have
transformed
understanding
and
design
of
stochastic
molecular
systems—biological,
chemical
physical—in
a
move
away
from
mechanical
macroscopic
analogies
that
dominated
thinking
regarding
dynamics
in
1990s
early
2000s
(e.g.
pistons,
springs,
etc),
to
more
scale‐relevant
concepts
underpin
out‐of‐equilibrium
research
sciences
today.
Ratcheting
has
established
nanotechnology
as
frontier
for
energy
transduction
metabolism,
enabled
reverse
engineering
biomolecular
machinery,
delivering
insights
into
how
molecules
‘walk’
track‐based
synthesisers
operate,
acceleration
reactions
enables
be
transduced
by
catalysts
(both
motor
proteins
synthetic
catalysts),
dynamic
systems
can
driven
equilibrium
through
catalysis.
The
recognition
biology,
their
invention
systems,
is
proving
significant
areas
diverse
supramolecular
chemistry,
covalent
DNA
nanotechnology,
polymer
materials
science,
heterogeneous
catalysis,
endergonic
synthesis,
origin
life,
many
other
branches
science.
Put
simply,
give
chemistry
direction.
Kinetic
asymmetry,
key
feature
ratcheting,
counterpart
structural
asymmetry
(i.e.
chirality).
Given
ubiquity
processes
significance
behaviour
function
it
surely
just
fundamentally
important.
This
Review
charts
recognition,
development
ratchets,
focussing
particularly
on
role
which
they
were
originally
envisaged
elements
machinery.
Different
kinetically
asymmetric
are
compared,
consequences
discussed.
These
archetypal
examples
demonstrate
inexorably
equilibrium,
rather
than
relax
towards
it.
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
63(9)
Published: Jan. 18, 2024
Abstract
Scientists
have
long
been
fascinated
by
the
biomolecular
machines
in
living
systems
that
process
energy
and
information
to
sustain
life.
The
first
synthetic
molecular
rotor
capable
of
performing
repeated
360°
rotations
due
a
combination
photo‐
thermally
activated
processes
was
reported
1999.
progress
designing
different
intervening
years
has
remarkable,
with
several
outstanding
examples
appearing
last
few
years.
Despite
accomplishments,
there
remains
confusion
regarding
fundamental
design
principles
which
motions
molecules
can
be
controlled,
significant
intellectual
tension
between
mechanical
chemical
ways
thinking
about
describing
machines.
A
thermodynamically
consistent
analysis
kinetics
rotors
pumps
shows
while
light
driven
operate
power‐stroke
mechanism,
kinetic
asymmetry—the
relative
heights
barriers—is
sole
determinant
directionality
catalysis
Power‐strokes—the
depths
wells—play
no
role
whatsoever
determining
sign
directionality.
These
results,
elaborated
using
trajectory
thermodynamics
nonequilibrium
pump
equality,
show
asymmetry
governs
response
many
non‐equilibrium
phenomena.
Nature,
Journal Year:
2025,
Volume and Issue:
637(8046), P. 594 - 600
Published: Jan. 15, 2025
Abstract
Cells
display
a
range
of
mechanical
activities
generated
by
motor
proteins
powered
through
catalysis
1
.
This
raises
the
fundamental
question
how
acceleration
chemical
reaction
can
enable
energy
released
from
that
to
be
transduced
(and,
consequently,
work
done)
molecular
catalyst
2–7
Here
we
demonstrate
molecular-level
transduction
force
8
in
form
contraction
and
re-expansion
cross-linked
polymer
gel
driven
directional
rotation
artificial
catalysis-driven
9
motors.
Continuous
360°
rotor
about
stator
motor-molecules
incorporated
polymeric
framework
twists
chains
network
around
one
another.
progressively
increases
writhe
tightens
entanglements,
causing
macroscopic
approximately
70%
its
original
volume.
The
subsequent
addition
opposite
enantiomer
fuelling
system
powers
reverse
direction,
unwinding
entanglements
re-expand.
Continued
twisting
strands
new
direction
causes
re-contract.
In
actuation,
motor-molecule
produces
other
physical
outcomes,
including
changes
Young
modulus
storage
modulus—the
latter
is
proportional
increase
strand
crossings
resulting
rotation.
experimental
demonstration
against
load
synthetic
organocatalyst,
mechanism
6
,
informs
both
debate
3,5,7
surrounding
generation
biological
motors
design
principles
6,10–14
for
nanotechnology.
Chem,
Journal Year:
2023,
Volume and Issue:
9(10), P. 2902 - 2917
Published: June 19, 2023
Biomolecular
machines
are
driven
by
information
ratchet
mechanisms,
where
kinetic
asymmetry
in
the
machine's
chemomechanical
cycle
of
fuel-to-waste
catalysis
induces
net
directional
dynamics.
A
large-scale
energetically
downhill
conformational
change,
termed
a
"power
stroke,"
has
often
been
erroneously
implicated
as
mechanistic
driving
feature
such
machines.
We
investigated
roles
and
power
strokes
series
rotaxane-based
ratchets
found
that
alone
determines
directionality
all
use
same
amount
fuel
to
reach
normalized
steady
state.
However,
can
nonetheless
influence
performance,
how
fast
state
is
reached.
Moreover,
nonequilibrium
thermodynamic
analysis
revealed
alter
form
(information
[Shannon
entropy]
versus
intercomponent
binding
energy)
free
energy
stored
ratchets.
These
findings
have
implications
for
both
understanding
biological
design
principles
artificial
(supra)molecular
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(47)
Published: Aug. 7, 2023
Abstract
Non‐equilibrium
chemical
systems
underpin
multiple
domains
of
contemporary
interest,
including
supramolecular
chemistry,
molecular
machines,
prebiotic
and
energy
transduction.
Experimental
chemists
are
now
pioneering
the
realization
artificial
that
can
harvest
away
from
equilibrium.
In
this
tutorial
Review,
we
provide
an
overview
ratchets:
mechanisms
enabling
absorption
environment.
By
focusing
on
mechanism
type—rather
than
application
domain
or
source—we
offer
a
unifying
picture
seemingly
disparate
phenomena,
which
hope
will
foster
progress
in
fascinating
science.
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(10), P. 5730 - 5738
Published: March 3, 2023
Single
enzyme
chemotaxis
is
a
phenomenon
by
which
nonequilibrium
spatial
distribution
of
an
created
and
maintained
concentration
gradients
the
substrate
product
catalyzed
reaction.
These
can
arise
either
naturally
through
metabolism
or
experimentally,
e.g.,
flow
materials
microfluidic
channels
use
diffusion
chambers
with
semipermeable
membranes.
Numerous
hypotheses
regarding
mechanism
this
have
been
proposed.
Here,
we
discuss
based
solely
on
chemical
reaction
show
that
kinetic
asymmetry,
difference
in
transition
state
energies
for
dissociation/association
product,
diffusivities
bound
free
forms
enzyme,
are
determinates
direction
result
positive
negative
chemotaxis,
both
demonstrated
experimentally.
Exploration
these
fundamental
symmetries
govern
behavior
helps
to
distinguish
between
possible
mechanisms
evolution
system
from
initial
steady
whether
principle
determines
shifts
when
exposed
external
energy
source
thermodynamics
kinetics
latter
being
supported
results
present
paper.
Our
that,
while
dissipation
ineluctably
accompanies
phenomena,
including
systems
do
not
evolve
maximize
minimize
but
rather
attain
greater
stability
accumulate
regions
where
their
effective
coefficient
as
small
possible.
The
chemotactic
response
formed
other
enzymes
participating
catalytic
cascade
provides
forming
loose
associations
known
metabolons.
Significantly,
force
due
depends
asymmetry
so
be
nonreciprocal,
one
attracted
another
repelled
one,
seeming
contradiction
Newtons
third
law.
This
nonreciprocity
important
ingredient
active
matter.
Small,
Journal Year:
2023,
Volume and Issue:
19(14)
Published: Jan. 26, 2023
Molecular
nonequilibrium
systems
hold
great
promises
for
the
nanotechnology
of
future.
Yet,
their
development
is
slowed
by
absence
an
informative
representation.
Indeed,
while
potential
energy
surfaces
comprise
in
principle
all
information,
they
hide
dynamic
interplay
multiple
reaction
pathways
underlying
systems,
i.e.,
degree
kinetic
asymmetry.
To
offer
insightful
visual
representation
asymmetry,
we
extended
approach
pertaining
to
catalytic
networks,
span
model,
focusing
on
system
dynamics
-
rather
than
thermodynamics.
Our
encompasses
both
chemically
and
photochemically
driven
ranging
from
unimolecular
motors
simple
self-assembly
schemes.
The
obtained
diagrams
give
immediate
access
information
needed
guide
experiments,
such
as
states'
population,
rate
machine
operation,
maximum
work
output,
effects
design
changes.
proposed
barrier
a
unifying
graphical
tool
disparate
phenomena.