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Engineering the Self-Assembly of Bacterial Microcompartment Shell Proteins via Charged Mutations.
Annie Gomez1,2,3, Behzad Mehrafrooz1,2, Curt Waltmann1,2
1Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States.
ACS Nano
|June 27, 2026
Summary
Scientists controlled protein self-assembly by altering protein charge, creating tubular nanostructures. This research advances biomaterial design and understanding of protein self-organization in bacterial microcompartments (MCPs).
Area of Science:
- Biomaterials Science
- Structural Biology
- Biophysics
Background:
- Protein self-assembly is crucial for designing novel biomaterials.
- Bacterial microcompartments (MCPs) serve as model systems for studying protein self-organization.
- Shell proteins like PduA and PduJ from MCPs naturally form tubular structures.
Purpose of the Study:
- To investigate methods for precisely controlling protein self-assembly.
- To explore the role of electrostatic interactions in protein nanostructure formation.
- To advance biomaterial design using protein self-assembly principles.
Main Methods:
- Systematic alteration of protein subunit charge (charge inversion and supercharging).
- Heterologous overexpression and cell-free protein synthesis platforms.
- Molecular simulations to predict self-assembled structures and analyze interactions.
- In vivo assembly competence testing in native bacterial systems.
Main Results:
- Increasing negative charge on PduA and PduJ hexamers promoted self-assembly into tubular structures.
- Molecular simulations predicted stable nanotubes and honeycomb sheets, elucidating stability and chirality.
- Charge-altered hexamers remained assembly competent within native bacterial microcompartments.
Conclusions:
- Protein charge and electrostatic interactions are key factors in controlling protein nanostructure formation.
- Protein self-assembly can be precisely modulated for biomaterial design applications.
- This work provides insights into both fundamental protein assembly and biotechnological capabilities.
Keywords:
bacterial microcompartmentscell-free protein synthesiselectrostatic engineeringnanostructure morphologyprotein self-assemblyshell protein designMore Related Videos
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