This year, our team contributed to the characterization of PBAD (K808000) by adding new validation data and demonstrating its application in an arabinose-inducible suicide system for biosafety. With only 17 members, we also developed a Team Management Guideline to help small teams work efficiently through clear division of labor and cross-support. In Human Practices, we created an Emergency Handbook for Families of Alzheimer’s Patients, providing practical guidance for urgent situations and caregiver support. We hope these contributions can serve as a valuable reference for future iGEM teams.

The Bronze part we contributed to is PBAD (K808000), originally designed by Team 04_MIT. In our project, we applied PBAD as an arabinose-inducible promoter to construct a controllable safety system. To strengthen the documentation of this part, we updated its Part Registry page with our experimental validation data.

Validation of PBAD promoter activity

We performed a Validation of PBAD promoter activity by testing gene expression at different concentrations of L-arabinose. A codon-optimized mRFP reporter was placed downstream of PBAD, and fluorescence was measured under varying induction conditions. Our results demonstrated that PBAD exhibited dose-dependent and rapid induction, with minimal leakage at 0% arabinose and strong expression at 0.2–0.5% arabinose.

Figure： Dose- and time-dependent induction of PBAD promoter activity by L-arabinose

Arabinose-inducible suicide system

Building on this, we designed an arabinose-inducible suicide system (PBAD–T4 lysis), where T4 holin and T4 lysozyme were placed under PBAD control. Experimental results showed that after arabinose induction at 4 h, the engineered strain underwent significant lysis, with OD600 dropping sharply compared to the control. By 20 h, growth was nearly abolished, confirming the functionality of PBAD–T4 lysis as a reliable biosafety “kill switch.”

Figure：Growth dynamics of DH5α and pBAD–T4 lysis strains after L-arabinose induction at 4 h

Through these experiments, we not only validated the inducibility and reliability of PBAD but also demonstrated its practical application in a biosafety containment system. This contribution enriches the part’s documentation and provides future iGEM teams with a well-characterized foundation for designing controlled expression and safety modules.

Our team this year consisted of 17 members, and some of them were quite busy, with limited time to complete tasks. We also faced challenges in synchronizing progress across different groups, though fortunately we managed to overcome them. Based on this experience, we compiled a Team Management Guideline designed for small iGEM teams with limited members. The guideline provides practical strategies on how to efficiently advance tasks with fewer people. It emphasizes clear division of labor, outcome-oriented planning, efficient communication, and cross-support between Wet Lab and Dry Lab members. It also outlines meeting systems, documentation standards, and complementary skills training to ensure that even a small team can maintain high productivity and cohesion. We hope this guideline can serve as a valuable reference for future iGEM teams facing similar challenges.

Figure：Team Management Guideline

During our Human Practices activities, we realized the critical importance of public education on Alzheimer’s Disease (AD). In response, we created an Emergency Handbook for Families of AD Patients. The handbook covers practical guidance on urgent situations such as preventing wandering, managing sudden agitation, handling falls and injuries, choking, and seizures, as well as self-care tips for caregivers.Our goal is to support caregivers whose needs are often overlooked, and to provide them with clear, actionable advice in times of crisis. At the same time, we hope this work can serve as a useful reference for future iGEM teams who wish to combine scientific innovation with real social impact.