Wednesday, May 04, 2011

Molecular origami


Take a look at the objects on the cover of this recent issue of Science. They might be exquisite baubles from a pharaoh's tomb, or golden treasures wrested from the Great Inca by Pizarro. Not quite. These are computer representations of actual objects made by folding strands of DNA into two- and three-dimensional shapes. The more obvious DNA strand threading the two flat objects is for illustration only; it is not to the same scale as the other objects but gives a better indication of what the wire-like structure of those objects consist of on a molecular scale.

Lest you think I'm pulling your leg, here are transmission electron microscope images of the flask.

This remarkable object is 40 nanometers in diameter and 70 nanometers tall. The claw of an ant is about ten thousand times larger than the flask. Ten thousand flasks could line up across the period at the end of this sentence. The flask is ten times smaller than the smallest bacterium.

The flask speaks to two things: First, the amazing potentialities of the DNA molecule; second, the equally amazing ability of scientists to manipulate nature on such an incredibly small scale. The folks who devised these objects are at the Biodesign Institute of Arizona State University.

So what's a nanoflask good for? I haven't a clue. What's the DNA-folding technology good for? When God invented (I speak metaphorically) the first self-replicating DNA molecule, I wonder if there were angels standing around wondering what it might be good for?



(Final composite photo from nationalgeographic.com. Click to enlarge.)