The use of gel electrophoresis to study the reactions of activated amino acids with oligonucleotides.

We have used gel electrophoresis to study the primary covalent addition of amino acids to oligonucleotides or their analogs and the subsequent addition of further molecules of the amino acids to generate peptides covalently linked to the oligonucleotides. We have surveyed the reactions of a variety of amino acids with the phosphoramidates derived from oligonucleotide 5'-phosphates and ethylenediamine. We find that arginine and amino acids that can interact with oligonucleotides through stacking interactions react most efficiently. D- and L-amino acids give indistinguishable families of products.