Cellulose Processing & CBDs
Testing the feasibility of microbial cellulose-based biosensors

The University of Edinburgh iGEM 2015 team is creating a paper-based biosensor to detect purity of and contaminants in illicit drugs. In an effort to increase the applications of the proof-of-concept biosensor, the team wanted to incorporate microbial cellulose as an alternative to paper. This could decrease the cost of the biosensor as well as making the disposal easier.

By using microbial cellulose that our team provided, the University of Edinburgh team was able to check the binding affinities of a cellulose binding domain (CBD) to the cellulose to see whether microbial cellulose-based biosensors are feasible. Our bioHYDRA project involved testing processed and unprocessed cellulose, and we sent the Edinburgh team a sample of each. This allowed the Edinburgh team to see if there is an advantage to the processing for their applications, and, since our future work includes expressing CBDs on spore coats, the processed sheets will be better for our applications as well. The CBD they tested was BBa_K1321357, which is sfGFP fused to CBDcex and driven by LacI. They chose this BioBrick because it was in the distribution kit and was already well-enough characterized to ensure that the only variable they tested was whether the sheets were processed. The data they provided shows that less protein dissociation occurred from the processed sheets.

Beyond the Bench

Despite the time zone difference, we held several skype meetings throughout the summer to discuss our collaborations and get to know each other. We also got together early on during the summer, sharing our enthusiasm over IGEM and the potential collaboration between the two teams. To celebrate our collaboration, the Edinburgh team baked an IGEM cake when we had a joint party with Brooke and Liusahd in California at the beginning of the summer!