In Vivo Expression of Genetic Information from Phosphoramidate-DNA.

Chemically modified genes and genomes with customized properties will become a valuable tool in numerous fields, including synthetic biology, biotechnology, and medicine. These genetic materials are meant to store and exchange information with DNA and RNA while tuning their functionality. Herein, we outline the development of an alternative genetic system carrying phosphoramidate linkages that successfully propagates genetic information in bacteria and at the same time is labile to acidic conditions. The P3'→N5' phosphoramidate-containing DNA (PN-DNA) was enzymatically synthesized by using 5'-amino-2',5'-deoxycytidine 5'-N-triphosphates (NH-dCTPs) as substrates for DNA polymerases and employed to encode antibiotic resistance in Escherichia coli. The resulting PN-DNA can be efficiently destroyed by mild acidic conditions, whereas an unmodified counterpart remains intact. A cloning strategy was proposed for assembling modified fragments into a genome. This method can be of interest to scientists working in the field of orthogonal nucleic acid genes and genomes.