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Updated: Sep 1, 2025

Synthesis of Information-bearing Peptoids and their Sequence-directed Dynamic Covalent Self-assembly
Published on: February 6, 2020
Sequence-Controlled Secondary Structures and Stimuli Responsiveness of Bioinspired Polyampholytes
Jelena Dinic1,2, Mathew R Schnorenberg2, Matthew V Tirrell1,2
1Center for Molecular Engineering and Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States.
The sequence charge pattern significantly impacts polyampholyte secondary structures. External stimuli like pH and ionic strength can tune these structures, differing from uniformly charged polypeptides.
Area of Science:
- Polymer Chemistry
- Biophysics
- Materials Science
Background:
- Polyampholytes are polymers with both positive and negative charges.
- Understanding their secondary structure is crucial for designing responsive materials.
- Sequence charge patterns are key determinants of polymer behavior.
Purpose of the Study:
- To investigate how sequence charge patterns influence polyampholyte secondary structure.
- To explore the responsiveness of these structures to external stimuli.
- To compare the behavior of distinct charge patterns.
Main Methods:
- Design and synthesis of two polyampholyte sequences with defined charge patterns.
- Characterization of secondary structure preferences.
- Assessment of structural changes under varying pH, ionic strength, and dielectric constant.
Main Results:
- Sequence charge pattern significantly affects secondary structure at physiological pH.
- External stimuli (pH, ionic strength, dielectric constant) modulate secondary structure.
- Structural transformations differ notably from uniformly charged homo-polypeptides.
Conclusions:
- The arrangement of charges, not just their fraction, dictates polyampholyte secondary structure.
- Polyampholytes offer tunable structural properties via environmental stimuli.
- These findings advance the design of intelligent polymer systems.
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