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Updated: Jul 19, 2026

Native Cell Membrane Nanoparticles System for Membrane Protein-Protein Interaction Analysis
Published on: July 16, 2020
Energetics of an n --> pi interaction that impacts protein structure
Jonathan A Hodges1, Ronald T Raines
1Departments of Chemistry and Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Abstract:
[structure: see text] The trans/cis ratio of the amide bond in N-formylproline phenylesters correlates with electron withdrawal by a para substituent. The slope of the Hammett plot (rho = 0.26) is indicative of a substantial effect. This effect arises from a favorable n --> pi interaction between the amide oxygen and ester carbonyl. In a polypeptide chain, an analogous interaction can stabilize the conformation of trans peptide bonds, alpha-helices, and polyproline type-II helices.
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