Living electro-biocatalyst scaffolds for sensing and cleaning

• Applicants: Professor Dr. Lorenz Adrian; Professorin Dr.-Ing. Zeynep Altintas
• Subject Area: Synthesis and Properties of Functional Materials ; Metabolism, Biochemistry and Genetics of Microorganisms
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 541301469

In this project, we combine the expertise of the groups Altintas (Materials Science, Biosensors and 3D-printing), Adrian (Metalloproteomics, Redox Enzymes, Organohalide Respiration and Bioremediation) and Budisa (Synthetic Biology and Xenobiology). Our aim is to develop a platform technology for the production of Engineered Living Materials with Adaptive Functions (ELM) in the field of sensor technology and biocatalysis. Our major objective in the materials field is to engineer an innovative laser patterning technique for 3D porous conductive hydrogels (PCH) that is both rapid and biocompatible. This technique will be used to produce biodegradable, environmentally stable PCH through laser-scribed phase separation (LSPS). PCH which will serve as conductive material for bacterial attachment allowing efficient electron transfer to living bacterial cells. LSPS will facilitate mass production of PCH-based electrode materials by integrating multiple fabrication processes into a single electrode preparation phase. Our major objective in the biology field is the engineering of genetically modified microbial cells that produce specific redox-active metalloproteins on their surface and to connect these redox-active metalloproteins via a conductive linker to the material surface using click chemistry under physiological conditions that do not impact the viability of the cells. Therefore, we will employ previously engineered E. coli cells that are able to synthesize the non-canonical amino acid L azidohomoalanine and to incorporate this amino acid at a programmed position via a refunctioned stop-codon. This allows us to define the position at which a protein is linked to a surface so that its near-surface [FeS] cluster comes into a conductive distance to the linker. In a joint approach, we will bring together the conductive PCH containing alkyne-residues for click chemistry with the microbial cells containing the reactive L-azidohomoalanine residues. We target to obtain a tight binding that conducts electrons. With this, we propose to develop a printable 3D-material with conductive adapters for engineered electroactive microbial cells. The cells are controlled through the conductive material by electron flux and can react with growth and differential expression of enzymes. Substrate turnover will result in a measurable current in the PCH. The application area is wide but we focus on environmental pollution.

• DFG Programme: Priority Programmes
• Subproject of: SPP 2451: Engineered Living Materials with Adaptive Functions
• International Connection: Canada
• Co-Investigator: Professor Dr. Nediljko Budisa