Contribution

The objective was to develop a colored and adhesive cellulose patch fully bio-based and biodegradable. To achieve this, we decided to work with two microorganisms: a cellulose-producing bacterium (Komagataeibacter rhaeticus) and a recombinant yeast (Saccharomyces cerevisiae) that will secrete proteins to functionalize the cellulose. Specifically, we genetically modified S. cerevisiae to enable it to excrete colored proteins (chromoproteins) and adhesive proteins (bioglue). To do this, we created a plasmid backbone that allows the insertion of any DNA sequence into the S. cerevisiae genome through homologous recombination. This plasmid backbone is now available to the entire community, and anyone wishing to integrate a gene into the S. cerevisiae genome can use it to effectively turn this organism into a biological factory for a wide range of recombinant proteins.

To create bacterial cellulose patches embedded with coloured and sticky proteins, we designed and engineered specific BioBricks, which we then transformed into the yeast S. cerevisiae. Each sequence of all BioBricks was codon-optimised for S. cerevisiae in order to achieve the best possible protein expression. We made the proof of concept by immunological detection of YFP into the supernatant of the yeast culture proving both its production and secretion. At this stage we lacked time to detect the proper production of the sticky proteins. Therefore, further experiments are required, and we hope that future iGEM teams will be able to enhance our parts. While our experiments have not yet proven the functionalization of the cellulose patch, we are pleased to make the sequences of our various biobricks, including BioGlue and chromoproteins, available to the wider community. These BioBricks form the foundation of our work and could be utilised by anyone with ideas for creating other sticky patches containing cellulose. We therefore consider these BioBricks as a significant contribution to the continuation of our project.

To produce our insect trap which has cellulose as a scaffold we used Komagataeibacter rhaeticus bacteria that produce cellulose naturally under specific conditions. Our team was able to produce patches of cellulose and show the feasibility and reproducibility of the protocol published in the paperthat inspired us. [1].

The protocol was done in our laboratory by the members of our team without any complications.

Once cellulose production by our bacterium was confirmed and the transformation of our yeast was verified, the co-culture between the two microorganisms was established. since the goal of this project is to produce functionalized cellulose patches through the co-culture of K. rhaeticus and recombinant S. cerevisiae expressing YFP and bioglue proteins. We followed the protocol outlined in the paper to perform co-cultures between our wild-type (WT) or recombinant S. cerevisiae and K. rhaeticus, the protocol was validated under both conditions. Our team once again demonstrates the potential of this protocol and the possibility for other iGEM teams to reproduce it.