Research on Living Materials: New Approaches for 3D Printing with Biological Structures

Researchers at Rice University have gained new insights into the interactions between genetic sequences, material structures, and mechanical properties. Their research enables more precise control over biologically engineered materials that respond differently to deformation forces such as tension or compression. These discoveries could lead to advancements in tissue engineering, drug delivery, and the 3D printing of living systems.

The study, published in ACS Synthetic Biology, focuses on modifying protein matrices that serve as structural networks for biological materials. Through targeted genetic modifications, the team was able to produce significant differences in the mechanical behavior of these materials.

“We are engineering cells to create customizable materials with unique properties,” said Caroline Ajo-Franklin, professor of biosciences and the study’s corresponding author. “While synthetic biology has given us tools to tweak these properties, the connection between genetic sequence, material structure and behavior has been largely unexplored until now.”

The research team worked with the bacterium Caulobacter crescentus, which was modified to produce a protein called BUD. This protein promotes cell adhesion and the formation of supporting structures, referred to as BUD-ELMs. Variations in specific protein segments led to the development of three different material types with varying stiffness and fracture resistance. Advanced imaging techniques and mechanical tests demonstrated that these differences were not merely superficial but also influenced the materials’ behavior under stress.

“This study is one of the first to focus on building living materials from the ground up with tailored mechanical properties rather than just adding biological functions,” said Esther Jimenez, a graduate student in biosciences and first author of the study. “By making small tweaks to protein sequences, we’ve gained valuable insights into how to design materials with specific mechanical properties.”

“This work emphasizes the importance of understanding sequence-structure-property relationships,” said senior Carlson Nguyen, a biosciences major and second author of the study. “By identifying how specific genetic modifications affect material properties, we’re building a foundation for designing next-generation living materials.”

These new materials exhibit shear-thinning behavior and can retain large amounts of water, making them well-suited for biomedical applications such as scaffolds for cell growth or controlled drug delivery. The research findings also open possibilities for environmentally friendly applications, including biodegradable structures or renewable energy generation. The insights gained contribute to the targeted design and further development of future living materials for specific use cases.