Genetically Engineered Yeast Could Enable Sustainable Martian Construction

• A research team from the Hong Kong University of Science and Technology has developed an 'Engineered Living Building Material' (ELBM) using yeast to construct habitats on Mars.
• The technique offers a low-energy alternative to traditional regolith sintering while allowing for material recyclability.

Technical Mechanisms

• Composition: A bio-composite of local Martian sand, gelatin, and genetically modified baker's yeast.
• Key genetic modifications:
  • Mussel Foot Proteins: Act as anchors to bond yeast to sand grains.
  • SpyTag/SpyCatcher System: Creates covalent isopeptide bonds for structural integrity.
  • Anti-freeze Proteins: Prevents ice crystals from shattering the structure during freeze-drying, creating a uniform porous network.

Performance and Limitations

• Advantages:
  • Requires nearly two orders of magnitude less energy than sintering with lasers or microwaves.
  • Demonstrates a compressive strength of 12 MPa and a high flexural strength of 6 MPa, useful for withstanding dust storms.
  • Recyclable through heating to 45℃ to reliquify the gelatin for recasting.
• Caveats:
  • Unclear impact of toxic perchlorates in Martian soil on yeast survival.
  • Unknown durability against constant ultraviolet radiation.
  • Porous nature requires an internal membrane for air retention.
  • Dependence on Earth-sourced gelatin remains a logistical hurdle.