Cornell University
A team of Cornell University scientists has shown in initial experiments that it might be possible to borrow sperm’s strategy for energy production and modify it to power nanodevices that could move through the human body, dispensing drugs, monitoring enzymes or performing other chores.
Borrowing strategy from sperm
In a mouse sperm, the long tail gets the energy it needs to swim from two sources. In the mid-piece, tiny power plants known as mitochondria generate energy, whereas a pathway known as glycolysis creates power within the tail’s principal piece. Cornell University scientists are borrowing the latter strategy to attempting to generate energy for nanodevices.
This simplified cross-section of the principal piece of the sperm tail shows the architecture of the black fibrous sheath, a scaffold-like support running the length of the tail. Several research groups have suggested that in sperm, the enzymes involved in glycolysis are all tethered to the fibrous sheath. Glycolysis produces energy from glucose, allowing the sperm to generate energy down the tail’s length.
The biological pathway known as glycolysis has 10 steps, each catalyzed by an enzyme. In the sperm tail, glycolysis produces energy for motor proteins (embedded in a structure called the axoneme) to create the bending action needed for sperm to swim. Cornell University researchers have proposed modifying these same glycolysis enzymes and tethering them to a solid support so a device could generate energy in the form of ATP.
As a proof of principle, Cornell University scientists attached the first two enzymes of the glycolysis pathway (including hexokinase, shown here) to a metal chip. The researchers found that not only do the modified sperm proteins bind to the chip, but by using the sperm’s attachment strategy, the proteins also possess much higher activity than if they are just randomly attached to a surface.
— Bryn Nelson
archimorph 
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