Borane phosphonate DNA: a versatile unnatural internucleotide linkage

TLDR: Borane phosphonate DNA is a promising molecule for biological applications as well as post-synthesis DNA modification, including DNA functionalization.

Abstract: Borane phosphonate (bp) is a new class of unnatural internucleotide linkages where one of the oxygens in the phosphodiester linkage is replaced by an electron deficient borane (BH3) group. These unnatural internucleotide linkages are resistant to nuclease, RNase H active and hydrophobic, which significantly enhance the cellular uptake. The bp-linked oligo can be synthesized both enzymatically and chemically. Like borane (BH3) and diborane (B2H6) reagents, the borane group (BH3) in borane phosphonate oligo retains its reactivity towards a specific substrate. BpDNA reduces metal ions, such as Au(III), Ag(I), and Pt(II), and produces the corresponding metal nanoparticles; this enables the DNA-mediated morphology control and spatial positioning of nanoparticles and DNA nanostructures. Moreover, the bp-diesters undergo oxidative substitution with various nucleophiles, such as amines, alcohols, thiols, etc., upon activation by iodine; this leads to a route for post-synthetic modification of DNA including DNA functionalization. This article discusses some of the recent studies reported on bp-oligo synthesis and its applications.