Integrated Human Practices serve as the cornerstone of responsible scientific research, requiring us to continuously reflect on whether our project aligns with societal expectations and creates positive impact. During the initial background investigation phase, we actively engaged with the public through questionnaires to understand societal perceptions of synthetic biology applications in space and preferences for product formats. These findings directly informed our project's communication strategy. Throughout the project's development, we maintained ongoing dialogue with diverse stakeholders, including laboratory researchers and other iGEM teams. Their invaluable perspectives became crucial references for our iterative improvements. It is precisely through this process of listening, understanding, and incorporating feedback that we continually refined our project, making each step forward a testament to collaborative wisdom.

In-depth development in specialized fields relies on the support of peers. We actively sought guidance from domain experts, whose advice helped us overcome critical technical bottlenecks. These interactions were not one-way consultations but collaborative learning processes that directly shaped our experimental design and strategic thinking.

Researcher Liu Yuzhong from South China University of Technology has extensive expertise in molecular biology. During the initial project design phase, we posed a key question: "Should the target protein be secreted for expression?" We initially believed secretory expression would facilitate product collection. He pointed out that our project involved expressing eukaryotic genes in prokaryotic systems, where overall yield tends to be low. Harvesting proteins via cell lysis would yield significantly more product than relying on secretory expression. This prompted us to reevaluate our technical approach. Post-discussion, literature review revealed that the protein secretion efficiency in hydrogen-oxidizing bacteria is generally below 30%, and pursuing secretory expression may lead to protein degradation. We promptly adjusted our strategy by: ① optimizing the His-tag position to avoid active sites, and ② incorporating chaperone proteins to aid folding and reduce inclusion body formation.

To further enhance yield, we explored knocking out competitive pathway genes to redirect energy toward product synthesis. In discussions with Researcher Liu Yuzhong on identifying optimal knockout targets, he emphasized the need to consider global metabolic network balance, noting that "solely enhancing precursor supply may disrupt energy metabolism." Following his advice, we first used genome-scale modeling to simulate the impact of single-gene knockouts on growth rate and product flux, then screened for endogenous genes critical to target protein synthesis but non-essential. We ultimately selected four key targets (areA, gcl, hutl, putA), which regulate competing pathways such as the glyoxylate shunt, histidine utilization, and proline degradation. This advice laid a solid foundation for building an efficient cell factory.

Researcher Tian Yiyuan from South China University of Technology has rich experience in autotrophic fermentation systems. We invited her to provide key technical guidance for the project. She noted that hydrogen-oxidizing bacteria are prone to metabolic lag during gas substrate transitions and recommended first accumulating biomass under heterotrophic conditions until OD₆₀₀ reached 1–2 before transitioning to autotrophic phase.

During promoter screening, she analyzed and advised that we prioritize evaluating the background expression levels of induction systems, emphasizing the need to "assess leakage expression." Subsequently, induction efficiency should be determined. Following her suggestions, we adopted a tiered evaluation system for four candidate induction systems (arabinose, lactose, propionate, rhamnose). We first measured leakage expression levels, excluding the lactose system due to high leakage. We then assessed induction kinetics and confirmed that arabinose offered the strongest induction, demonstrating highest efficiency at 2 g/L concentration. This systematically validated induction scheme provided a key regulatory foundation for subsequent high-efficiency protein expression.

Researcher Wu Haiyan from South China University of Technology has substantial practical experience in protein expression and purification. During initial purification, we observed faint SDS-PAGE bands in elution products, indicating poor binding to nickel columns. While we initially suspected failed His-tag linkage, electrophoresis confirmed successful C-terminal tagging. We consulted Researcher Wu Haiyan about our purification process. She alerted us to imidazole concentration, noting that "premature use of high-concentration imidazole may compete with target proteins for nickel column binding sites, preventing effective binding." She also recommended adopting a gradient elution scheme. After implementing these changes, purified protein yield increased significantly.

Collaboration with other iGEM teams provided us diverse perspectives.

In May 2025, we participated in the 9th Southern China Reginal Meeting. We presented our project and actively engaged with other teams at our booth. Discussions with teams including Shenzhen University and South China Agricultural University yielded constructive feedback. Members from other team raised doubts about whether prokaryotic cells could express eukaryotic genes. Although this gene had been successfully expressed in Bacillus subtilis, no prior precedent existed for its expression in hydrogen-oxidizing bacteria. Consequently, we paid particular attention to this aspect in subsequent research and experiments. First, after literature review, we abandoned the idea of secretory expression to ensure protein synthesis. Second, we screened two molecular chaperones to assist synthesis, including human-derived hPDI, which is homologous to our target human gene and may facilitate expression in hydrogen-oxidizing bacteria. Experimental results confirmed this, as plasmids incorporating hPDI yielded higher protein concentrations than those with SLY1 after transformation.

We also established in-depth collaboration with the MUST-space team. We both focus on space synthetic biology, meaning we may face shared challenges. We learned that MUST hosts a national key laboratory for space science, equipped with a microgravity simulator—a key instrument we lacked. Further exchanges covered team formation and funding sources. In July, the teams held an in-depth online meeting to explore the possibility of testing engineered strains under simulated microgravity. Although cross-border policies ultimately prevented physical transfer of microorganisms, this exchange provided significant strategic value.

Our products are ultimately developed for human use. Therefore, to develop a scientific project that truly aligns with societal expectations, we have consistently placed public dialogue at the core of our innovation process. Through systematic questionnaire surveys and community interactions, we gathered public attitudes and suggestions regarding our project. This section will demonstrate how public opinions have shaped the direction of our work and the profound insights brought by societal recognition.

We conducted a questionnaire survey among residents. A total of 276 valid responses were collected in this community survey, covering a wide range of age groups and demonstrating a relatively balanced gender distribution, which ensures broad representativeness.

The survey revealed that the majority of respondents were unfamiliar with the concept of "synthetic biology" (over 80% combined in "Never heard" and "Heard but don't understand"). Our science introduction sparked significant interest among them.

A majority of respondents showed openness to trying the product (approximately 70% combined in "Very willing" and "Probably would try"). Among the unwilling group (83 respondents), "Safety concerns" was the primary hesitation (64 selections), while "Psychological aversion to the source" (48 selections) and "Perceived as unnatural/unhealthy" (42 selections) can be viewed as indirect apprehensions and a lack of trust in the product's technological safety, pinpointing crucial directions for future product refinement.

Regarding product form, "Protein energy bars" emerged as the most preferred option by a significant margin (148 selections, 53.6%), while "Protein powder" also garnered considerable support (81 selections, 29.3%). This provides clear market guidance for our product form strategy.

Finally, over 94% of respondents expressed interest in following the project's progress ("Very willing" and "Somewhat interested"), indicating that our project concept has garnered significant market attention and positive preliminary acceptance.

Our interactions with the public yielded invaluable outcomes beyond expectations. The support from respondents for applying synthetic biology technologies to space exploration strengthened our confidence in advancing the project. The public's preference for portable forms such as protein bars provided clear guidance for product design. Positive feedback from diverse age groups further validated the social value of our project. These findings not only affirm our research path but also serve as critical references for driving continuous improvement.