Adaptive biomaterials through mechano-modulating bacteria

• Applicants: Professor Dr.-Ing. Andreas Blaeser; Professor Dr. Heinz Koeppl
• Subject Area: Biomaterials ; Biomedical Systems Technology ; Synthesis and Properties of Functional Materials ; Metabolism, Biochemistry and Genetics of Microorganisms ; Cell Biology
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 541299811

The integration of living cells into biomaterials allows for harnessing the sophisticated embodied intelligence of cells in the design of novel adaptive biomaterials. The cell’s exquisite sensing capabilities and ist versatile production capacities provide unprecedented means to equip materials with adaptive functionality. The use of modern synthetic biology tools allow for rewiring of existing sensing pathways or the engineering of entirely new molecular functionality in an efficient and increasingly rational manner. In this project, we aim to utilize synthetic biology to genetically build new sense-process-response capabilities into microorganisms that interact with the matrix material in a bidirectional way. More specifically, we will engineer E. coli to respond to mechanical stress exerted at the cell wall through the expression and secretion of matrix modulating factors. In particular, we will design genetic circuits for stress-induced gene expression of matrix reinforcing and degrading agents. Among many possible variants, this will enable materials that can automatically reinforce themselves along major stress-lines and become softer at low-stress regions. We will evaluate compatibility of different matrix base materials and their compositions for E. coli viability and for force-transduction onto the bacteria. For biochemical transduction of stress we will harness the RcsCDB two-component system but we will also agnostically screen for promoters responsive to mechanical stress. We will rigorously characterize the matrix-modulating effect of the resulting engineered bacteria in a quantitative manner. Leveraging our 3D-bioprinting capabilities, we will deposit those bacteria in spatially resolved ways in order to realize novel 3D origami-type structures. Finally, we will utilize our new engineered living material (ELM) to provide a proof-of-concept for a new manufacturing paradigm. In this biomorphic approach, materials are trained repeatedly with the desired stress profiles and will automatically build up an emergent load-bearing structure that is optimal for the applied stress. The project will advance our fundamental understanding of ELMs and thereby provide novel findings on mechano-sensing in bacteria, elucidate ist potential for redesign in synthetic biology and generate new design and fabrication technologies for adaptive biomaterials.

• DFG Programme: Priority Programmes
• Subproject of: SPP 2451: Engineered Living Materials with Adaptive Functions