Large scale production of synthetic spider silk proteins in Escherichia coli

• Published in: Protein expression and purification 2021-07, Vol.183, p.105839-105839, Article 105839
• Main Authors: Bhattacharyya, Gargi, Oliveira, Paula, Krishnaji, Sreevidhya T., Chen, Dong, Hinman, Michael, Bell, Brianne, Harris, Thomas I., Ghazitabatabaei, Amir, Lewis, Randolph V., Jones, Justin A.
• Format: Article
• Language: English
• Subjects: Animals; Antibiotic pressure; Arthropod Proteins - biosynthesis; Arthropod Proteins - genetics; Bioreactor; Escherichia coli - genetics; Escherichia coli - metabolism; Gene Expression; High-density culture; Metabolic engineering; Recombinant Proteins - biosynthesis; Recombinant Proteins - genetics; Repetitive protein; Silk - biosynthesis; Silk - genetics; Spiders - genetics; Synthetic spider silk
• ISSN: 1046-5928; 1096-0279
• DOI: 10.1016/j.pep.2021.105839

Spider silk, which has remarkable mechanical properties, is a natural protein fiber produced by spiders. Spiders cannot be farmed because of their cannibalistic and territorial nature. Hence, large amounts of spider silk cannot be produced from spiders. Genetic engineering is an alternative approach to produce large quantities of spider silk. Our group has produced synthetic spider silk proteins in E. coli to study structure/function and to produce biomaterials comparable to the silks produced by orb-weaving spiders. Here we give a detailed description of our cloning, expression, and purification methods of synthetic spider silk proteins ranging from ~30 to ~200 kDa. We have cloned the relevant genes of the spider Nephila clavipes and introduced them into bacteria to produce synthetic spider silk proteins using small and large-scale bioreactors. We have optimized the fermentation process, and we have developed protein purification methods as well. The purified proteins are spun into fibers and are used to make alternative materials like films and adhesives with various possible commercial applications. •Spider silk protein mechanical properties.•Genetic engineering approach to produce spider silk.•Fermentation process optimized for recombinant spider silk production.•High level of recombinant spider silk expressed in bacteria.