Abstract
AbstractIn order to generate a library of DNA-encoded chemical compounds it is necessary to covalently attach multiple encoding tracts of DNA to each compound. The most widely practiced methodology to achieve this utilizes the enzymatic ligation of 5'-monophosphate oligodeoxynucleotide tags to 3'-hydroxyl oligodeoxynucleotide tags, typically with recombinant T4 DNA Ligase. This approach can be challenging owing to the inherent incompatibility of conditions supporting the enzymatic activity of T4 DNA Ligase with the specific conditions that are required for each chemical synthesis step. An alternative approach (pioneered at X-Chem) is to use non-enzymatic chemistry to join oligonucleotides together in a manner that supports downstream applications such as the generation of wild-type complementary DNA (cDNA), which can in turn be used as a template for PCR to support subsequent cloning and sequencing. A range of different chemistries may be used to support these processes, each paired with a specific molecular biological strategy to support the generation of cDNA.