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Updated: May 30, 2026

Interactive Molecular Model Assembly with 3D Printing
Published on: August 13, 2020
Effect of Steric Constraint at the γ-Backbone Position on the Conformations and Hybridization Properties of PNAs
Matthew J Crawford1, Srinivas Rapireddy, Raman Bahal
1Department of Chemistry, Center for Nucleic Acids Science and Technology (CNAST), Mellon Institute, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, USA.
Abstract:
Conformationally preorganized peptide nucleic acids (PNAs) have been synthesized through backbone modifications at the γ-position, where R = alanine, valine, isoleucine, and phenylalanine side chains. The effects of these side-chains on the conformations and hybridization properties of PNAs were determined using a combination of CD and UV-Vis spectroscopic techniques. Our results show that the γ-position can accommodate varying degrees of sterically hindered side-chains, reaffirming the bimodal function of PNAs as the true hybrids of "peptides" and "nucleic acids."
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