Our Project

We aim to develop a novel bio-textile to tackle the severe environmental pollution caused by the traditional textile industry. Current sustainable alternatives, like bacterial cellulose, often lack color and require separate, resource-intensive dyeing processes, which contradicts the goal of eco-friendliness. To overcome this limitation, we engineered an E. coli-based platform that integrates bacterial cellulose synthesis and dyeing into one single step. By utilizing temperature-switch (CI857 and FourU), our engineered bacteria first produced bacterial cellulose at 25°C and then synthesized natural pigments at 37°C, resulting in intrinsically colored bio-textiles. Additionally, we have designed a waterproof module to enhance the fabric's practicality.

Figure 1. Expected usage of the bacterial cellulose.

Our Final Product

Our final product is a self-colored, waterproof bio-textile film. The production process begins with culturing our engineered E. coli in a fermenter. The entire journey from cell cultivation to finished colored fabric is completed in one bioreactor simply by adjusting the temperature. This one-pot synthesis significantly reduces water usage, energy consumption, and chemical waste compared to conventional methods. Laboratory tests have confirmed that our system successfully produces bacterial cellulose films dyed with pigments like eumelanin.

Device

Cellulose Synthesis Module: Includes lyophilized plasmid DNA, E. coli DH5α competent cell and a bioreactor. Dyeing Module: Includes lyophilized plasmid DNA, E. coli BL21(DE3) competent cell and a bioreactor. Waterproof Module: Includes the BslA-dCBM protein powder (a biofilm-surface layer protein A with a double cellulose binding module), Protein solvent, a mixing container, and an application brush.

Steps

1. Activation: Co-culture E. coli DH5α and E. coli BL21(DE3) containing the corresponding plasmid DNA at 37°C overnight with shaking.
2. Cellulose Synthesis Module: Aseptically transfer the activated culture to the bioreactor. Set and maintain temperature at 25°C for cellulose formation.
3. Dyeing Module: Shift and maintain bioreactor temperature to 37°C for several hours to induce colors.
4. Harvesting and Post-processing: Harvest the colored bacterial cellulose film. Sterilize and dry the material.
5. Waterproof Module: Dissolve the BslA-dCBM protein powder in protein solvent. Apply to film via dip-coating or spray-coating. Air-dry to form a hydrophobic layer.

Storage

Lyophilized plasmid DNA and protein powders should be stored at -20°C to ensure their long-term stability and activity.

The colored bacterial cellulose is not limited to the fashion industry. It can be engineered for a wide range of applications by modifying the properties of the cellulose or the pigments used. We envision expanding our platform into multiple product lines to meet diverse needs. The key advantages of our colored bacterial cellulose include:
1. Customizable Colors: We are moving beyond a simple color palette to a programmable one. By introducing different pigment synthesis pathwaysinto our engineered E. coli, we can produce a full spectrum of colors on demand. This allows for limitless design possibilities for fashion designers and brand owners seeking unique, sustainable colors.
2. Diverse Functions: The nano-porous structure of bacterial cellulose allows for the integration of a range of bioactive compounds during synthesis. This capability to embed therapeutic agents directly into the material matrix makes it ideal for advanced applications beyond clothing, such as in medicated wound dressings and skincare textiles^[1].
3. Biocompatibility: Our bacterial cellulose are inherently biocompatible and biodegradable. This makes them ideal for a range of medical and well-being applications without the risk of irritation or adverse reactions associated with synthetic fibers and chemical residues^[2].
4. Eco-friendliness: From production to disposal, our material is designed with a closed-loop life cycle. The one-pot synthesis drastically reduces water consumption and eliminates the toxic chemical effluent associated with conventional dyeing. The final product is derived from renewable resources and, at the end of its life, can fully biodegrade, returning to the environment without contributing to microplastic pollution. This positions our threads as the foundational material for a truly circular economy in textiles and beyond^[3].

Figure 2. The applications and advantages of the colored bacterial cellulose.

For Products

Our final product kit contains lyophilized powder, which may cause related biosafety issues due to the leakage of the lyophilized powder into the environment. Therefore, in possible future applications, we strongly recommend that our users avoid damaging the test kit when using it, and hand over the used kit to professionals for recycling. In the subsequent industrial production and product processing, the bacterial cellulose membranes we produce will be sterilized according to the corresponding standards.

For Experiment

Throughout the whole experiments, we have fully complied with iGEM's security policy and all pertinent national laws. All our validations were done in the laboratory without releasing any engineered bacteria into the environment. During the course of our experimental procedures, we also employed lyophilized powder and rigorously adhered to regulations to prevent any environmental contamination.

Although our material has proven effective under laboratory conditions, several challenges remain for large-scale industrial application. The yield and production speed of bacterial cellulose in E. coli need further optimization to compete with traditional fabrics. The color fastness, durability, and feel of the bio-textile must be rigorously tested against industry standards. We are actively working on metabolic engineering to enhance yield and pigment stability, and we seek partnerships with industry leaders to test our materials in real-world conditions and refine the product for commercial viability.

• [1]Wu J, Zheng Y, Song W, et al. In situ synthesis of silver-nanoparticles/bacterial cellulose composites for slow-released antimicrobial wound dressing[J]. Carbohydrate Polymers, 2014, 102: 762-771.
• [2]Joseph A, Umamaheswari S, Vassou M C. Bacterial cellulose: a versatile biomaterial for biomedical application[J]. Carbohydrate Research, 2025, 552: 109350.
• [3]Venturelli G, Villa F, Petraretti M, et al. Bacterial cellulose for scalable and sustainable bio-gels in the circular economy[J]. Gels, 2025, 11(4): 262.