Chaput has had a long-standing interest in tinkering with chemical building blocks used to make molecules like proteins and nucleic acids that do not exist in nature. When it came time to synthesize the first self-assembled GNA nanostructures, Chaput had to go back to basics. The idea behind the research was what to start with a simple DNA nanostructure that we could just mimic.
The first self-assembled DNA nanostructure was made by Ned Seemans lab at Columbia University in 1998, the very same laboratory where ASU professor Hao Yan received his Ph.D. Chaputs team, which includes graduate students Richard Zhang and Elizabeth McCullum were not only able to duplicate these structures, but, unique to GNA, found they could make mirror image nanostructures.
In nature, many molecules important to life like DNA and proteins have evolved to exist only as right-handed. The GNA structures, unlike DNA, turned out to be enantiomeric molecules, which in chemical terms means both left and right-handed.
Making GNA is not tricky, its just three steps, and with three carbon atoms, only one stereo center, said Chaput. It allows us to make these right and left-handed biomolecules. People have actually made left-handed DNA, but it is a synthetic nightmare. To use it for DNA nanotechnology could never work. Its too high of a cost to make, so one could never get enough material.
The ability to make mirror image structures opens up new possibilities for making nanostructures. The research team also found a number of physical and chemical properties that were unique to GNA, including having a higher tolerance to heat than DNA nanostructures. Now, with a new material in hand, which Chaput dubs unnatural nucleic acid nanostructures, the group hopes to e
|Contact: Joe Caspermeyer|
Arizona State University