Synopsis: Mechanical proteins

New techniques measure mechanical properties of proteins without damaging them.
Synopsis figure
Credit: Yong Wang

Nanorheology⎯the study of deformation of matter, particularly complex molecules, at the nanoscale⎯is beginning to give a clearer picture of the mechanics of biological macromolecules such as proteins and short DNA strands, both of which can act as molecular springs.

In their paper in Physical Review Letters, Yong Wang and Giovanni Zocchi at the University of California, Los Angeles, apply the techniques of rheology to the motion of charged gold nanoparticles tethered to a gold surface by globular proteins.

The particles are driven by an alternating current that produces deformations in the protein chain. With evanescent scattered light from a laser, the authors probe the frequency-controlled motion of the protein and determine its spring constant and friction coefficient. The deformations are small, leading to a strain of only around 1%, allowing the authors to measure mechanical properties of the protein without damaging it, an advantage over other common methods. – Sami Mitra


More Features »


More Announcements »

Subject Areas

Soft MatterBiological PhysicsInterdisciplinary Physics

Previous Synopsis

Soft Matter

Adapting to habitat

Read More »

Next Synopsis

Particles and Fields

A question of size

Read More »

Related Articles

Synopsis: How Ice Bridges Form

Synopsis: How Ice Bridges Form

New theoretical work predicts the conditions under which sea ice will clog a narrow channel to create a natural bridge across it. Read More »

Synopsis: Little Spheres Are Pushy
Soft Matter

Synopsis: Little Spheres Are Pushy

A simple diffusion model explains why small particles tend to push big ones to the bottom of a drying colloid film. Read More »

Synopsis: Racing Bacteria
Biological Physics

Synopsis: Racing Bacteria

Bacteria track fast-moving chemical signals by hopping from one chemically favorable region to another. Read More »

More Articles