Contribution

1. Integration of Light-Control Systems with Pigment Synthesis Pathways​​

Traditional dye production often relies on plant extraction or IPTG-induced expression in bacteria, leading to unnecessary chemical pollution and uneconomical production costs. To apply dye synthesis systems in textile dyeing and serve the field of artistic painting, we aimed to achieve on-demand dye synthesis. In this study, blue, red, and green light-control systems were coupled with the synthesis pathways of indigo, 6-bromoindigo, and 4,4-dinitroindigo, respectively, enabling precise regulation of the production of these three pigments under specific wavelengths of light.

After integrating the light-control systems, light exposure regulates the activation or inactivation of photosensitive proteins and controls dye synthesis through light-responsive promoters. As a result, IPTG induction is no longer needed for dye production in E. coli, significantly reducing production costs. Moreover, by varying the area of light exposure, the pattern and coverage of bacterial dyeing on textiles can be precisely controlled. In summary, the integration of light-control systems with pigment synthesis pathways provides a novel strategy for spatiotemporal regulation of pigment production.

2. Synthesis of Halogenated Indigos (6BrIG/6ClIG)

Traditional synthesis of halogenated indigos relies on chemical halogenating reagents, which is plagued by issues such as harsh reaction conditions, high levels of impurities in products, and severe pollution. Additionally, microbial synthesis of halogenated indigos mostly involves the static expression of a single halogen source. Based on the halogenase SttH, this study achieved the synthesis of 6,6'-dibromoindigo (6BrIG) and 6,6'-dichloroindigo (6ClIG). It is the first study to discover that sttH requires no modification—by merely replacing halogen donors (KBr/NaCl), it can simultaneously catalyze both the bromination and chlorination of tryptophan, resulting in the synthesis of purple 6BrIG and pale red 6ClIG respectively. Meanwhile, suitable fermentation conditions for synthesis were also identified, which lowered the threshold for multi-pigment synthesis.

​​3. Design of a Novel 4,4'-Dinitroindigo Synthesis Pathway​​​​

Based on the foundation of previous research, our project designed a new pathway for synthesizing 4,4'-dinitroindigo from tryptophan. This compound produces a green color when used to dye cotton fabrics.

At the current experimental stage, due to time constraints, we were unable to fully validate the feasibility of this pathway. The present design still faces practical challenges such as low theoretical yield and difficulties in purification. We anticipate that future efforts involving protein engineering may enhance the synthesis efficiency. Meanwhile, we hope that this design can provide insights and references for future research.

1.Long-term collaboration with Facilitators

The Facilitators' creative activities for Migrant Children will be a long-term collaborative project to help more migrant children integrate into synthetic biology and the wider learning field, and the project will continue to embody our inclusive philosophy.

To achieve this, the project team will design a series of interactive workshops that cater to various age groups of migrant children. These workshops will be held in community centers, schools, and other accessible locations to ensure maximum participation. The activities will be developed in a way that is both engaging and educational, using hands-on experiments, storytelling, and collaborative projects to spark the children's interest in synthetic biology.

2.Guidelines for ethical engagement

We contributed to the community's understanding of responsible innovation, documenting our approach to balancing artistic expression with scientific responsibility as well as sharing our methodology for assessing both intended and unintended impacts of bio-art installations.

Specifically, we've made a Draft Framework for Safety and Ethical Management of Bio-Art. Based on our practical experience, we have drafted forward-looking policy recommendations aimed at promoting standardized management in the bio-art field. This draft proposes:

1.Bacterial Immobilization Strategy via Hydrogel

To realize the concept of in situ bacterial dyeing in this project, we innovatively proposed the use of hydrogel to immobilize bacteria at specific locations on textiles, thereby addressing the issue of bacterial dispersion during the dyeing process. Experimental results demonstrated that the bacteria effectively produced indigo within the hydrogel and successfully dyed the fabric. In terms of biosafety, a dual-layer hydrogel strategy was adopted to effectively prevent Escherichia coli from escaping the hydrogel during light induction and to avoid contamination of the bacterial culture by external microorganisms.

2.Hardware Design

Concurrently, a hardware setup was designed for bacterial-based patterning in this project, capable of automated hydrogel spraying, movement of working sites, light irradiation, and high-temperature sterilization. The designed hardware is fully functional, constructed with an aluminum alloy frame, and features a clearly modular design, facilitating replication or iterative improvements based on our existing work.

1.Light-Controlled System Modeling

In the field of microbial metabolic regulation, light signals, as key environmental factors, their influence mechanism on pigment synthesis pathways has always been a research difficulty. Traditional studies mostly rely on experimental observations and require modeling results to predict the rationality of the design. To address this issue, we conducted a systematic modeling study.

Taking the design of a blue light-controlled system as an example, we constructed a mathematical model encompassing key processes such as receptor activation, signal transduction, and metabolic enzyme expression. Core parameters like transcription and translation efficiency were incorporated. Subsequent simulations successfully predicted the concentration curves of the key protein PhlF under different light conditions, verifying the rationality of the design. Meanwhile, this provides a reusable modeling framework for research on other light-regulated metabolic pathways.

2.Protein Modeling

Protein-protein docking is a crucial process in life activities, and its structural dynamic changes directly determine the realization of biological functions. To explore the feasibility of electron transfer between proteins designed by the research group, we conducted protein docking modeling studies and predicted the structural stability through dynamic simulations.

Firstly, based on homology modeling and the molecular docking software HDOCK, we constructed docking predictions between target proteins, along with the display of confidence scoring, interface residues, and hydrogen bond interactions. Subsequently, we performed molecular dynamics simulations using GROMACS to predict the dynamic changes during protein docking and capture conformational transitions at key time nodes.

This modeling and visualization achievement verifies the feasibility of the team's experimental design, provides a basis for subsequent experiments, and also serves as a template for similar protein design verification.

3. Microbial Melody

In the microbial melody module, the team has formed core contributions with both technological innovation and social value, focusing on target detection for colony identification, microbe-to-music conversion, and popular science needs of visually impaired individuals.

In the aspect of target detection for colony identification, aiming at the pain points such as difficulty in quantifying microbial growth and missed detection of small colonies, the team adapted the YOLOv8s target detection technology to the colony identification scenario and trained a colony detection tool with excellent recognition performance, providing reference and assistance for personnel with similar needs.

The application of the artistic translation system not only allows visually impaired groups to perceive the process of microbial growth through hearing, but also the microbial music adds artistry to this project. It enables the public who are not familiar with the project to intuitively feel the growth of bacterial colonies through music. This technology also provides new ideas for interdisciplinary artistic creation and promotes the in-depth integration of science and art.