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Updated: May 26, 2026

Production of Disulfide-stabilized Transmembrane Peptide Complexes for Structural Studies

Production of Disulfide-stabilized Transmembrane Peptide Complexes for Structural Studies

Published on: March 6, 2013

Cis-trans peptide variations in structurally similar proteins.

Agnel Praveen Joseph¹, Narayanaswamy Srinivasan, Alexandre G de Brevern

¹INSERM UMR-S 665, Dynamique des Structures et Interactions des Macromolécules Biologiques, Université Denis Diderot-Paris 7, INTS, 6 rue Alexandre Cabanel, Paris Cedex 15, France.

|January 10, 2012

Summary

Cis peptides, crucial for protein structure and function, are often not conserved in similar protein folds. These cis-trans conformation changes drive protein evolution and the emergence of new functions.

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Area of Science:

Structural Biology
Protein Chemistry
Evolutionary Biology

Background:

Cis peptides are vital for protein structural integrity and function.
Cis-trans peptide bond inter-conversion plays a key role in protein folding.

Purpose of the Study:

To analyze the conservation of cis peptides across similar protein folds.
To investigate amino acid preferences and local structural changes associated with cis-trans variations.

Main Methods:

Comparative analysis of cis peptide conservation in structurally related proteins.
Examination of amino acid propensities and local conformational changes.
Utilizing Protein Block-based description for backbone conformation analysis.

Main Results:

Approximately 34% of Xaa-Proline cis bonds are not conserved in related structures.
Glycine residues flanking peptide bonds show a higher propensity to adopt the trans conformation.
Over 30% of cis conformations in beta turns (types VIb and IV) are not conserved.
Local conformational changes associated with cis-trans variations differ significantly from general structural variations.

Conclusions:

Cis-trans peptide bond conversions are significant drivers of protein evolution.
These conformational changes facilitate the emergence of new functions, particularly in enzyme active sites.
Cis-trans conversions also play a role in inter-domain and inter-protein interactions.