Term: secondary structure
https://doi.org/10.1351/goldbook.S05530

Definition:
The conformational arrangement (α-helix, β-pleated sheet, etc.) of the backbone segments of a macromolecule such as a polypeptide chain of a protein without regard to the conformation of the side chains or the relationship to other segments.

Related Terms:
1) primary structure (http://doi.org/10.1351/goldbook.P04843).
2) tertiary structure (http://doi.org/10.1351/goldbook.T06282).
3) quaternary structure (http://doi.org/10.1351/goldbook.Q05004).
4) helix (http://doi.org/10.1351/goldbook.H02769).
5) backbone (http://doi.org/10.1351/goldbook.B00574).
6) conformation (http://doi.org/10.1351/goldbook.C01258).

Source: PAC, 1996, 68, 2193. 'Basic terminology of stereochemistry (IUPAC Recommendations 1996)' on page 2218 (https://doi.org/10.1351/pac199668122193)

Citation: 'secondary structure' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.S05530

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