Fig. 3

Schematic of the genetic engineering of spider silk proteins, exemplified by two major ampullate spidroin derivatives, namely, ADF3 and ADF4 (Araneus diadematus fibroin), from the European Garden Spider Araneus diadematus. Based on the general structure and amino acid consensus sequences of the repetitive core modules of ADF3 and ADF4, engineered spider silk protein mimics eADF3 and eADF4 are derived by a reverse translation approach that combines PCR-amplified authentic gene fragments and engineered synthetic DNA modules into gene cassettes. After the cloning of multimerized constructs and transformation into a bacterial host, such as E. coli, the engineered silk proteins are recombinantly produced, extracted, purified, and lyophilized for storage. Adapted from [46] with permission from Springer Nature