Single-chain heteropolymers transport protons selectively and rapidly
Tao Jiang1,2, Aaron Hall1, Marco Eres1,3
1Department of Materials Science and Engineering, University of California Berkeley, Berkeley, CA, USA.
Nature
|January 10, 2020
Summary
Random heteropolymers (RHPs) mimic natural proton channels without atomic structuring. These polymers facilitate selective proton transport across lipid bilayers, achieving performance comparable to natural systems.
Area of Science:
- Biomimetic chemistry
- Polymer science
- Membrane biophysics
Background:
- Natural channels achieve precise structure and chemical diversity for proton transport.
- Synthetic channels using peptides, DNA, and polymers have not matched natural performance.
Purpose of the Study:
- To investigate random heteropolymers (RHPs) as a novel approach for selective proton transport.
- To demonstrate RHPs can mimic membrane proteins and achieve natural-like proton transport rates.
Main Methods:
- Fabrication of four-monomer-based random heteropolymers (RHPs).
- Insertion of RHPs into lipid bilayers to form functional proton transport pathways.
- Analysis of RHP structure-function relationships for proton transport.
Main Results:
- RHPs enabled selective proton transport across lipid bilayers at rates comparable to natural proton channels.
- Segmental hydrophobicity heterogeneity in RHPs facilitated bilayer insertion.
- Bilayer-spanning polar segments in RHPs formed hydrogen-bonded chains for proton transport.
Conclusions:
- Statistical control over RHP monomer distribution is key to achieving protein-like function.
- Adaptability and modularity in RHPs enable uniform behavior in heterogeneous systems.
- Statistical randomness offers a new strategy for designing single-polymer-chain biomimetic systems.
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