ALBUQUERQUE, N.M. — A novel method of simulating protein behavior to achieve new, desirable nanostructures has been achieved in prototype by two researchers from Sandia National Laboratories.
The method treats proteins like little construction crews, sequencing and controlling their molecular behaviors to build structures of interest.
“A bird builds a nest differently each time, but you end up with a nest that works,” says Sandia Fellow Gordon Osbourn, who developed the method with his colleague and wife, Sandia physicist Ann Bouchard. “We build simulated nanostructures the same way.”
“There are many paths to a useful outcome in our method,” says Bouchard. “Many details in how the assembly happens don’t matter. As long as the conditions are met [for protein interactions], we get a result we care about.”
“The method requires a different mindset when designing self-assembly programs,” says Osbourn. “Instead of moving electrons around transistor circuits, we move molecules around, and add or remove them from constantly changing nanostructures.”
The pair uses relatively unreliable stochastic processes to achieve a result that may be a nanowire or nanowall. Stochastic or random behavior is one way nature works, offering a range of possibilities rather than a single solution.
Polymer lengths and number of molecules represent components of the program, which include motor proteins, their cargo, and constantly varying microtubules. Molecules may be attached or removed, or added or subtracted, and operate along time-dependent pathways that change as sites where molecules can attach, called docking sites, become visible or disappear. The process simulates protein behavior outside the animal cells in which they are normally found, a process other researchers have already demonstrated is accurate.
“We have shown,” says Osbourn, “that through stochastic simulations, certain protein self-assembly processes can act as a novel form of programmable computation, equivalent to Turing machines.”
The pair is working with experimentalists “to carry out the experiments suggested by our simulations and build the structures by following the steps demonstrated by the simulated components,” says Bouchard.
Osbourn is one of six researchers to attain the title of Fellow at Sandia in the last 50 years. The title is awarded to those researchers of unusual insight whose hard work have brought about new ideas and notable advances in science and technology.