SYNTHESIS AND SUPRAMOLECULAR POLYMERIZATION OF PEPTIDE NUCLEIC ACID-CONTAINING MONOMER

Abstract

Nucleobase-induced self-assembly interaction, have gained much attention as potential non-covalent driving force for generating interesting assembled structures. Pyrrolidinyl peptide nucleic acid (PNA), with (2′R,4′R)-prolyl/(1S,2S)-2-aminocyclopentanecarboxylic acid backbone (acpcPNA) has shown the recognition with complementary nucleic acids following Watson-Crick base rules. Another PNA system having different stereochemistry on proline ring with a backbone of (2′R,4′S)-prolyl/(1S,2S)-2-aminocyclopentanecarboxylic acid backbone (epi-acpcPNA) can undergo self-pairing. Here in this work, both acpcPNA- and epi-acpcPNA-functionalized monomers consisting of two PNA segments joined together by a flexible polyethylene glycol linker were prepared on solid support, purified by high performance liquid chromatography (HPLC) and characterized by MALDI-TOF mass spectrometry. The acpcPNA- and epi-acpcPNA-functionalized monomers showed the hybridization with complementary DNA and self-hybridization, respectively, as revealed by melting temperature and circular dichroism (CD) experiments. However, the hybridization of acpcPNA with complementary DNA and the self-hybridization of epi-acpcPNA did not lead to the proposed supramolecular polymerization as observed from analysis by Field emission scanning electron microscopy (FESEM) and polyacrylamide gel electrophoresis (PAGE).