Biological Supercomputer Runs on ATP

A supercomputer with proteins running in channels, powered by the living energy molecule ATP. How can this work? Find out from the PNAS article by Dan Nicolau and coworkers at McGill University.

The computer involves large numbers of protein molecules flowing down channels. The channels have two kinds of junctions: split (equal chance of flow both ways) or pass (only flow across). The flow of molecules is of course random, but over large numbers they will find all possible paths. See movie.

What kind of problem can the proteins solve? The problem is to find all the possible target sums from a subset of a given set of integers. This kind of problem is well suited to a system that substitutes large numbers of nanoscopic particles for large amounts of computing time.

What drives the molecules forward? The researchers used two kinds of biochemical motor: the actin-myosin motor of muscles, and the microtubular motor of cell division. Both kinds worked, which is impressive.

And here’s the actin motor in action, viewed by fluorescence imaging.

Another impressive feature is the energy requirements, powered by ATP. Biochemical motors are relatively efficient, releasing far less heat than our fan-cooled machines.

As for accuracy–and scaling up–alas, that’s all far in the future. But not to worry, the researchers say. Even better than muscle proteins, the next computer components will be “dividing microorganisms.” Say what? That will solve all our problems, no doubt.