A simple procedure for constructing 5'-amino-terminated oligodeoxynucleotides in aqueous solution

Abstract
A rapid method for the synthesis of oligodeoxynucleotides (ODNs) terminated by 5′-amino-5′-deoxy-thymidine is described. A 3′-phosphorylated ODN (the donor) is incubated in aqueous solution with 5′-amino-5′-deoxythymidine in the presence of N-(3-dimethyl-aminopropyl)-N′-ethylcarbodiimide hydrochloride (EDC), extending the donor by one residue via a phosphoramidate bond. Template- directed ligation of the extended donor and an acceptor ODN, followed by acid hydrolysis, yields the acceptor ODN extended by a single 5′-amino-5′-deoxythymidine residue at its 5′ terminus.