Nucleic Acid Enzyme-Based DNA Nanomachine for Biosensing - DNA Nanotechnology: From Structure to Function - page 300

Fig. 14.2 Scheme of a walking DNAzyme and its track. ( a ) The walking principle. ( b )A
construction where the walking DNAzyme is at one end of its track. Black lines : template ( T ); green
lines : substrate ( S ); red / yellow lines : a 10-23 DNAzyme ( red ), with the catalytic core highlighted
( yellow ); blue dots indicate the bonds to be cleaved by the DNAzyme (Reproduced from Ref. [ 17 ]
by permission of John Wiley & Sons Ltd.) (Color figure online)
Stojanovic and coworkers used the similar concept and construct a “DNA spider”
that moves across an origami-based track [ 18 ]. In this study, four biotinylated 10-23
DNAzymes were attached to the four binding sites of streptavidin to give the “body”
with four catalytic “legs.” This molecular assembly can be made to walk across a
“lawn” of substrate molecules. Cleavage of the substrates means that the walker can
never return to areas it has visited before. Even though the motion is essentially
diffusive, it can be made directional by defining one-dimensional tracks of substrate
molecules. This has resulted in the first autonomous molecular walkers covering
distances on the order of 100 nm. Recently, Turberfield et al. designed a DNAzyme-
based motor that could navigate through a network of tracks containing four possible
routes [ 19 ]. The path of this DNA motor could be programmed using instructions