Designing a small DNA origami that can fold in several almost equivalent ways demonstrates how understanding and guiding the folding pathway can improve the efficiency of the folding process, potentially leading in more complex situations to higher yields of the desired nanostructure and fewer misfolded structures.
Archive for the 'Artificial Molecular Machines' Category
An extensive review of artificial molecular machines, their large-amplitude motions, and the changes these motions produce, emphasizes small molecules and the central role of chemistry in their design and operation.
Simple molecular switches based upon bistable mechanically interlocked molecules can be incorporated within pre-assembled metal organic frameworks and addressed electrochemically.
A review of molecular parts that act as switches, motors, and ratchets illuminates similarities between artificial and biological molecular machines and argues that useful applications are coming.
A pliers-shaped molecule in which two covalently linked naphthalene moieties serve as the hinge connecting the two halves of the pliers, and each naphthalene connects the hydrophobic handle with the hydrophilic jaw of that half, opens and closes in response to surprisingly little energy applied to a molecular monolayer.
Modeling DNA strand displacement cascades according to three simple rules can in principle mimic the temporal dynamics of any other chemical system, presenting a method to model regulatory networks even more complicated than those of biology.
Functional ribosomes with subunits engineered to not separate at the completion of each protein translation cycle make possible engineering systems to make a variety of novel polymers with novel properties.
At the 2013 Conference Joseph Puglisi described how single molecule fluorescence techniques were used to study changes in the conformation and composition of the ribosome, a large biomolecular nanomachine, during the process of translation of genetic information.
A molecular ring shuttles back and forth between two positions on a molecular axle held rigidly inside a solid state molecular lattice made from a metal organic framework.
At the 2013 Conference George Church presented an overview of his work in developing applications of atomically precise nanotechnology intended for commercialization, from data storage to medical nanorobots to genomic sequencing to genomic engineering to mapping individual neuronal functioning in whole brains.
Programmed assembly and disassembly of rigid 3D DNA origami objects has been achieved by designing complementary surface shapes based upon weak stacking interactions to create simple nanomachines.
A rotaxane-based single molecule pump combines cycling oxidation-reduction potential of the solution with kinetic barriers to moving backward to concentrate small ring molecules against an energy gradient.
At the 2013 Conference Dean Astumian contrasted macroscopic machines at static equilibrium and molecular machines at dynamic equilibrium, and presented information ratchets and microscopic reversibility as the organizing principle of molecular machines.
RNA origami brings new dimensions to nucleic acid nanotechnology by exploiting the much greater variety of RNA structural motifs (compared to DNA) to do what cannot easily be done with DNA origami, like fold into predetermined nanostructures rapidly while being transcribed.
A commentary over at Gizmodo argues that ideas about molecular manufacturing that sounded like science fiction in 1986 now sound more like science fact.
Bulk nanoscale technologies were used to create three-segment nanowires of gold and nickel, and magnetic bearings of gold, nickel, and chromium. Combinations of DC and AC electric fields were used to assemble nanomotors that can spin at speeds up to 18,000r.p.m., and for up to 15 hours.
An overview of three decades of progress in DNA nanotechnology emphasizes bringing programmed motion to DNA nanostructures, including efforts to incorporate design principles from macroscopic mechanical engineering.
Variable length single-stranded DNA springs determine how far a hinge of double-stranded DNA joining two stiff sections of DNA origami can bend.
Scaffolded DNA origami is combined with hinges of single- or double-stranded DNA to built simple machines parts that have been combined to program simple to complex motions.
Among the smallest molecular robots reported so far, a walker based on phenylarsonous acid with two organic thiol ligands as feet walks through a one-nanometer-diameter protein nanopore channel by taking 0.6 nanometer steps, by thiol exchange, from one cysteine residue to the next.