posted on 2023-05-30, 19:03authored byAoi Mameuda, Masahiro Takinoue, Koki Kamiya
The majority of biological reactions
in the cytoplasm of living
cells occur via enzymatic cascade reactions. To achieve efficient
enzyme cascade reactions mimicking the proximity conditions of enzymes
in the cytoplasm, the proximity of each enzyme, creating a high local
concentration of proteins, has been recently investigated using the
conjugation of synthetic polymer molecules, proteins, and nucleic
acids. Although there have been methodologies reported for the complex
formation and enhanced activity of cascade reactions due to the proximity
of each enzyme using DNA nanotechnology, one pair of the enzyme (GOx
and HRP) complex is only assembled by the mutual independence of various
shapes of the DNA structure. This study reports the network formation
of three enzyme complexes assembled by a triple-branched DNA structure
as a unit, thus enabling the reversible formation and dispersion of
the three enzyme complex networks using single-stranded DNA, RNA,
and enzymes. It was found that the activities of the three enzyme
cascade reactions in the enzyme–DNA complex network were controlled
by formation and dispersion of the three enzyme complex networks,
due to the proximity of each enzyme with the enzyme–DNA complex
network. Furthermore, three micro RNA sequences for breast cancer
biomarkers were successfully detected using an enzyme–DNA complex
network integrated with DNA computing. Overall, the reversible formation
and dispersion of the enzyme–DNA complex network through the
external stimulation of biomolecules and DNA computing provide a novel
platform for controlling the production amount, diagnosis, theranostics,
and biological or environmental sensing.