To those who don’t believe in a Technological Singularity – really ? behind schedule ? no progress ? There just had to be a specification of which artificial DNA breakthrough is being discussed from announcements made this year.
A new class of DNA-like oligomers made exclusively of nonnatural, stable C-nucleosides. The nucleosides comprise four types of nonnatural bases attached to a deoxyribose through an acetylene bond with the β-configuration. The artificial DNA forms right-handed duplexes and triplexes with the complementary artificial DNA. The hybridization occurs spontaneously and sequence-selectively, and the resulting duplexes have thermal stabilities very close to those of natural duplexes. The artificial DNA might be applied to a future extracellular genetic system with information storage and amplifiable abilities.
Artificial DNA made exclusively of nonnatural nucleosides with four types of nonnatural bases represents a new class of DNA-like synthetic oligomers. The iG*/iC*-rich artificial DNA forms right-handed duplexes with the complementary artificial DNA in a sequence-specific manner with antiparallel orientation. The thermal stabilities and thermodynamic parameters of the artificial duplexes are very close to those of the natural duplexes in spite of differences in their geometries and hydrogen-bonding patterns. On the other hand, the artificial homooligomeric DNAs consisted only of A* and T* were found to exclusively form triplexes. By means of the synthetic feasibility of the artificial nucleoside unit, a variety of candidates for nonnatural bases can be incorporated into the artificial DNA. Therefore, the present molecular framework has a potential for storing genetic information and for application to enzymatic replication directed toward engineered genetics. Furthermore, the artificial DNA may be a superior building scaffold for constructing nanostructures of materials interest because of the stable C-nucleosides against ubiquitous naturally occurring enzymes such as DNase.