ARTSILK was succesful in completing all of the set goals:
The full characterization of the major ampullate gland by genomic, bulkRNA, single cell RNA and spatial transcriptomics sequencing was published recently (Sonavane et al. Science Advances. 2024). This work revealed that there are six cell types in the gland that are spatially distinct in their distribution and that produces specific mixtures of spider silk proteins. Furthermore, we could show that the protein mixtures form three layers in the final fiber.
The previously unexplored strategy to incoprorate hydrophobic amino acid residues in the poly-Ala blocks of the spider silk proteins was a success. We could, by using this strategy, produce artificial silk fibers with the same toughness as native spider silk while still keeping the all-aqueous processing conditions (Arndt et al. Advanced Functional Materials. 2022). A surprising finding was that most ofthese modified recombinant spider silk proteins could be produced as efficiently as the unmodified protein.
We have also managed to develop a production process that results in 10 times higher protein yields than has ever been achieved before and shown that we from a 1,6 liter culture can extract enough silk proteins to spin a 125 km long fiber. This opens up the possibility to commercialize artificial silk, in particular since also the protein engineered proteins that gave superior fibers also could be produced at the same extreme levels. The work was published by Schmuck et al in Materials Today in 2021 and in et al. Advanced Functional Materials. 2022, and received a lot of media attention. We have also managed to improve the properties of our fibers by optimizing the rheological properties of our spinning dope (Arndt et al. ACS Biomaterials Science and Engineering 2021) and by screening almost 100 different spinning conditions and by making changes to the spinning device (Gonska et al. Biomacromolecules. 2020; Greco et al. Communications materials. 2021; Schmuck et al Communications materials. 2022; Greco ACS Applied Polymer Materials. 2024). As a result of our success we have received funding from industrial partners and two Proof of Concept grants to further develop our fibers and scale up the spinning method.
The work performed in ARTSILK has been disseminated through various channels: national TV and radio, several international magazines and daily newspapers, lectures for the public, a chapter in a popular scientific book, outreach activities at science festivals, visit to the lab by school classes and representatives from different authorities. Scientifically we have been very productive in reporting our findings and results in scientific journals and presented the work at several international conferences. Furthermore, we have submitted three patent applications based on finding s in ARTISLK, and have received funding to explore the possibility of commercializing our material.
