Stray cats is a thorny problem, but we proposed an innovative solution coherent to our project. Through a number of online and field research, we perceived the severity of this problem and broadened our perspective. We thoughtfully incorporated ‘value sensitive design’ throughout our human practice, connecting different stakeholders from the society. In practice, we communicated with stray cat rescue teams for advice, and collaborated with organisations like Maker Space and environmental NGOs to get more information, and furthermore, raise public awareness on this issue. We interviewed many citizens to collect comprehensive opinions and suggestions, which make our design more viable. Moreover, we inquired laws and regulations from relevant governmental departments to community level in order to ensure smooth implementation of our applied design. Above all, we have made a series of documentary about our human practice and the process of conceiving, building and improving our applied design: “Kitty Wonderland”.

We hosted a workshop on synbio and its application, and hold an exhibition of our project in the international Maker Faire. We discussed with audiences including artists, students, investors and engineers who inquired about the safety and potential of synbio eagerly. And engineers and artists established long-term collaboration with us on applied design. We closely engaged with neighbourhood, urban management agencies and animal welfare groups, presenting how microbial factory can integrate with cat shelter we built to solve the problem of feral cats. Through direct interviews, in-depth conversations, presentations or polls, we learnt their concerns and how synbio-related design can be better accepted by the public. Innovatively, we connect with people in art field by holding activities which allow the public to draw and design the cat shelter. Moreover, we filmed a series of documentaries to reach even further, by uploading them on popular media platforms.

We built an ODE kinetics framework to model the mutualistic co-culture system of E.coli and S.cerevisiae we intended to use in our project, taking into account substrate utilization, product inhibitions and product formation involved in two species’ interactions. By recording the growth of the two engineered strains in co-culture and performing parameter sensitivity analyses, we were able to better interpret the behavior of the system.
In addition, we have also devised a model to analyze the relationship between E.coli’s geraniol production level and the copy number of the plasmid containing the two key enzymes for production, GES and GPPS, under the stabilization of different transcription activator-like effectors stabilized promoters(TALEsp) from our promoter library, so as to choose the desired combination for optimal geraniol production. The model can also be applied to choosing TALEsp for other situations involving tuning expressions of genes or maximizing down-stream production stabilized by TALEsp.

Free-roaming feral cats have posed a serious threat to public health and biodiversity. The current solution to manage feral cats called Trap&Neuter&Release often fail to control cats’ population due to the difficulties in capturing them. Aiming at the microbial production of nepetalactol, an ingredient in the cat-attracting plant catnip, we proposed the use of microorganism-derived nepetalactol for capturing feral cats and have devised a cat shelter, “Kitty Wonderland” as an implement tool of this idea. Through active communication with animal rescue NGOs, government, and hardware specialists, we optimised the design of Kitty Wonderland overtime, ensuring it’s safe and practical. Nonetheless, the cat shelter may be subjected to vandalism if our society didn’t realise the importance of respecting animals’ life and welfare. Thus, we employed public education as a complimentary component to the Kitty Wonderland.

In order to solve the stray cats problem, we devise this hardware, the Kitty Wonderland, to provide homeless stray cats with shelters which could offer them a safe, comfortable and permanent living environment. Through the interviews and discussions we made with specialists, officials and residence, we improve our hardware to combine the merits of existing methods like Trap&Neuter&Release. The hardware assists volunteered caregivers by attracting stray cats and capturing them if necessary, so the difficulties and costs in tracking and taking care of stray cats are greatly reduced. Besides, we apply nepetalactol, which is the focus of our project, to our hardware to make it more effective in attracting cats and emphasize the significance of our project. Finally, our hardware can be easily deployed on various locations in the community where it stresses the stray cats problem to a broad population in an original approach.