[Enzymatic synthesis of high-modified DNA]

Here, we describe the synthesis and purification of six deoxyuridine triphosphate derivatives that contain protein-like functional groups and alkene linkers of various lengths. Using KOD XL and Deep Vent polymerases, these derivatives have been incorporated into single-stranded DNA, achieving a high degree of DNA modification. These polymerases are able to utilize highly modified DNA strands as templates for synthesizing unmodified DNA. The synthesized deoxyuridine triphosphate derivatives are promising as substrates for producing modified aptamers to various target proteins using, e.g., the systematic evolution of ligands by exponential enrichment (SELEX) methodology.