Hybrid Living Capsules Autonomously Produced by Engineered Bacteria

Area of Science:

• Biomaterials Engineering
• Synthetic Biology
• Microbiology

Background:

• Bacterial cellulose (BC) possesses desirable material properties and sustainable production methods.
• BC-producing bacteria, like Gluconacetobacter hansenii, have limited genetic engineering capabilities compared to model organisms such as Escherichia coli (E. coli).
• There is a need for enhanced genetic toolkits to expand the functionality of BC-based materials.

Purpose of the Study:

• To develop a method for producing highly programmable BC materials by incorporating engineered E. coli.
• To create hybrid BC-E. coli capsules with novel functionalities.
• To expand the application potential of BC-based living materials.

Main Methods:

• Co-culturing Gluconacetobacter hansenii with engineered E. coli in glucose-rich media droplets to form cellulose capsules.
• Colonization of cellulose capsules by E. coli upon transfer to selective lysogeny broth media.
• Encapsulation of engineered E. coli within the BC matrix for protein nanofiber production and biomineralization.

Main Results:

• Successfully produced robust cellulose capsules containing engineered E. coli.
• Demonstrated production of engineered protein nanofibers within the BC matrix by encapsulated E. coli.
• Created hybrid capsules capable of sequestering biomolecules and performing enzymatic catalysis.
• Developed capsules that can modify their physical properties via enzyme-induced biomineralization.

Conclusions:

• A simple, two-bacterial co-culture system enables the creation of programmable BC materials.
• This approach significantly expands the functionality of BC-based living materials.
• The developed hybrid capsules offer potential for applications in biomolecule sequestration and catalysis.