How can synthetic biology contribute to carbon negative building materials?

Synthetic biology contributes to carbon-negative building materials by using biological systems and bioinspired processes to turn carbon dioxide into solid structural elements while avoiding the high emissions of traditional manufacturing ^[1][2].

Bioengineered Concrete Additives

Researchers have engineered materials like enzymatic structural material (ESM), which uses carbonic anhydrase, an enzyme that speeds up the reaction between water and carbon dioxide ^[3][4]. This rapid reaction generates carbonic acid that, when introduced to calcium, forms solid calcite crystals that act as a natural mineral binder for sand and carbon ^[5].

Mycelium-Based Bricks

Scientists also develop engineered living materials using fungal mycelium, such as the root-like network of the fungus Neurospora crassa ^[6]. This fungal scaffold can support complex geometries and be mineralized either by the fungus itself or through bacterial mineralization to create low-emission alternative building blocks ^[7].

Microbial Mineralization Processes

Microbial mineralization often relies on microbially induced calcium carbonate precipitation (MICP) ^[8]. For instance, bacteria like Sporosarcina pasteurii can be introduced to structural scaffolds to rapidly hydrolyze urea and remove dissolved calcium, creating stiff mineral coatings around biological fibers under mild conditions ^[9].

Carbon Accounting Benefits

Traditional ordinary Portland cement (OPC) manufacturing is energy-intensive, relies on high-temperature fossil-fuel kilns, and accounts for 5% to 8% of global anthropogenic carbon dioxide emissions ^[10][11]. Conventional concrete emits about 330 kilograms of carbon dioxide per cubic meter and requires a 28-day curing period ^[12][13]. In contrast, enzymatic structural materials can be molded within hours and actually sequester more than 6 kilograms of carbon dioxide per cubic meter ^[14].Would you also like to know more about the mechanical properties and compressive strength of enzymatic structural material?