Engineered Living Materials (ELMs) are revolutionizing the field of materials by merging the latest advancements in material science and biology. They bridge the gap between two key trends: the growing demand for smart, adaptable materials and the increasing focus on drawing inspiration from nature. By exploiting biological systems in a material setting, ELMs can revolutionise multiple industries, as diverse as healthcare, construction or agriculture. Recently, mycelium materials gained much attention in the material industry because of their robustness, versatility, rapid growth and ability to self-heal. However, engineering these materials to add more advanced functionalities is still a hurdle. A promising approach is to combine these structural mycelium materials with engineered bacteria. They have been exploited in various processes and materials because of their versatile bioactivities, which are continuously expanding with the major advances in synthetic biology. The mycelium is thus an ideal structural partner, where the engineered bacteria can serve as a functional partner, providing the material with a dynamic functionality, i.e. structural alterations, catalytic capabilities or responsiveness.

However, the integration of both mycelium and bacteria in ELMs faces several challenges, including viability during cultivation and leaching of the bacteria during the user phase of the material. Both issues can be tackled by physical attachment of the bacteria to the mycelium. This project aims to discover carbohydrate binding domains that are expressed on the bacterial surface and bind to mycelial cell walls, creating a physical link between bacteria and mycelium. This will be applied to multiple bacterial and fungal strains to maximise applicablility and versatility of the system.

Growth conditions of different strains can differ majorly in terms of growth medium, incubation times or optimal pH. The physical attachment of bacteria to the mycelium material allows for separate cultivation of both microorganisms in their preferred environment, followed by a joint incubation step where the bacteria bind the material. This way, full fitness is secured for both microorganisms during growth. Additionally, the attachment of the bacteria to the fungal cell wall will facilitate durable and long-lasting functionality and biosafety of the material once it is distributed. This research will contribute to the development and implementation of mycelium-bacteria based living materials.