A Proximity-Based Programmable DNA Nanoscale Assembly Line
We
have combined a gold nanoparticles with PX-JX2 devices and a novel
walker that walks on a track on a DNA origami to produce a programmable
assembly line. There are three
stations on the origami, each of which contains a PX-JX2 cassette,
and can contribute a unit of cargo to the walker. The cargoes consist of a 5 nm gold nanoparticle, a pair of
joined 5 nm gold nanoparticles, and a 10 nm gold nanoparticle. The devices will only donate a cargo if
the are programmed to do so by being put in the PX state, rather than the JX2
state as the walker passes the station.
The image below shows the assembly of the 3-component product.
The 11
steps indicate the addition to the three cargo components to the walker. The right column of panel (a) is shown
in a tapping mode AFM image in panel (b).
With
three different stations, it is possible to program eight different products
from this assembly line. These are
shown in the drawing below. Panel
(a) shows the possible trajectories that the assembly line can take to produce
eight different products. Panel (b)
shows the eight ending configurations of the assembly line, as a function of
the programming, before release of product. Panel (c) shows transmission electron micrographs of the
individual programmed products.