Peptide nucleic acids (PNA) aptamers represent a new class of therapeutics. Aptamers (lat.: “fitting particle”) are single – or double-stranded nucleic acids, which form defined and stable structures. These structures can bind specifically to targets and be used for capture or inhibition applications, similar to antibodies. The normal process to generate and isolate aptamer sequences is by an evolutionary method called “SELEX”. However, one crucial point in the selection process is the enzymatic amplification of the aptamer. PNA is a synthetic nucleic acid analog. It resembles the structure of DNA, but is based on a peptide backbone. Since PNA is structurally in between DNA and peptides it is neither effectively degraded by nucleases nor by proteases, making it a potentially very valuable substance class for novel therapeutics. However, due to the synthetic structure, PNA can not be amplified by normal enzymes used in molecular biology. Hence, a selection of PNA aptamers by classical SELEX is not possible.
PLS-Design has developed a patent protected process were the sequence information of PNA aptamers is transferred to DNA and therefore accessible for amplification and identification.
The development is in advanced research state. Optimization of enzymatic activities is currently pursued to make the selection process more efficient.