Not all biological movements are caused by molecular motors sliding along filaments or tubules. Just as springs and ratchets can store or release energy and rectify motion in physical systems, their analogs can perform similar functions in biological systems. The energy of biological springs is derived from hydrolysis of a nucleotide or the binding of a ligand, whereas biological ratchets are p...

F(O)F(1)-ATP synthases are ubiquitous proton- or ion-powered membrane enzymes providing ATP for all kinds of cellular processes. The mechanochemistry of catalysis is driven by two rotary nanomotors coupled within the enzyme. Their different step sizes have been observed by single-molecule microscopy including videomicroscopy of fluctuating nanobeads attached to single enzymes and single-molecul...

The use of mechanochemistry to carry out enantioselective reactions has been explored in the last ten years with excellent results. Several chiral organocatalysts and even enzymes have proved to be resistant to milling conditions, which allows for rather efficient enantioselective transformations under ball-milling conditions. The present article reports the first example of a liquid-assisted g...

The interplay between mechanical strains and battery electrochemistry, or the tunable mechanochemistry of batteries, remains an emerging research area with limited experimental progress. In this report, we demonstrate how elastic strains applied to vanadium pentoxide (V2O5), a widely studied cathode material for Li-ion batteries, can modulate the kinetics and energetics of lithium-ion intercala...

Rho is a ring-shaped hexameric motor protein that translocates along nascent mRNA transcript and terminates transcription of select genes in bacteria. Using a numerical optimization algorithm that simultaneously fits all of the presteady-state ATPase kinetic data, we determine how Rho utilizes the chemical energy of ATP hydrolysis to translocate RNA. A random hydrolysis mechanism is ruled out b...

Hydrogen uptake during the mechanochemistry of lithium nitride under 9 MPa hydrogen pressure has been analyzed by means of in situ solid-gas absorption and ex situ X-ray diffraction (XRD) measurements. In situ hydrogenation curves show two H-sorption steps leading to an overall hydrogen uptake of 9.8 wt% H after 3 hours of milling. The milled end-products consist of nanocrystalline (∼10 nm) LiN...

The molecular motor protein kinesin plays a key role in fundamental cellular processes such as intracellular transport, mitotic spindle formation, and cytokinesis, with important implications for neurodegenerative and cancer disease pathways. Recently, kinesin has been studied as a paradigm for the tailored design of nano-bio sensor and other nanoscale systems. As it processes along a microtubu...

Single-molecule force-clamp spectroscopy offers a novel platform for mechanically denaturing proteins by applying a constant force to a polyprotein. A powerful emerging application of the technique is that, by introducing a disulfide bond in each protein module, the chemical kinetics of disulfide bond cleavage under different stretching forces can be probed at the single-bond level. Even at for...

The pentameric ATPase motor gp16 packages double-stranded DNA into the bacteriophage phi29 virus capsid. On the basis of the results of single-molecule experimental studies, we propose a push and roll mechanism to explain how the packaging motor translocates the DNA in bursts of four 2.5 bp power strokes, while rotating the DNA. In this mechanism, each power stroke accompanies P(i) release afte...