by In a groundbreaking achievement, scientists have successfully created full-length spider silk fibers using genetically modified silkworms. These fibers are extremely strong and have the potential to offer a scalable and sustainable alternative to synthetic fibers such as nylon. Silkworm silk is currently the only animal silk fiber that is commercially available on a large scale, making it an ideal candidate for genetic modification to produce spider silk fibers. This new development could revolutionize the production of this highly sought-after natural material.
For thousands of years, silkworms have been used to produce silk, but the resulting fibers are known to be brittle. On the other hand, spiders produce silk that is incredibly tough and strong, but it has been impossible to cultivate it on a large scale due to the cannibalistic nature of spiders. This recent study aims to combine the best qualities of both silkworm silk and spider silk to create a new, superior material. Scientists have been working on perfecting this technique for over a decade, and this breakthrough brings them one step closer to achieving their goal.
To create the bionic silkworms, the researchers focused on a small silk protein found in the orb-weaving spider, Araneus ventricosus. Using the gene-editing tool CRISPR-Cas9, they inserted the gene that codes for this spider silk protein into the DNA of the silkworms, replacing the gene that codes for their own silk protein. This genetic modification did not interfere with the silkworm’s ability to produce its natural silk, and the spider silk gene was successfully activated. This localized approach, along with the proposed minimal structural model, sets this research apart from previous attempts.
The resulting silk fibers surpassed the expectations of the researchers, exhibiting high tensile strength and toughness. The fibers had a tensile strength of 1,299 megapascals (MPa) and a toughness of 319 megajoules per cubic meter (MJ/m3). Additionally, the fibers were more flexible than anticipated, as the spider silk protein is known for producing strong but non-stretchy silk.
The potential applications of this new silk are vast and include surgical sutures, military and aerospace technology, biomedical engineering, and garments. The fibers produced are six times tougher than Kevlar, the material commonly used in bulletproof vests. This indicates that the new silk has the potential to enhance the safety and performance of various products.
The researchers plan to further develop the genetically modified silkworms to produce spider silk fibers using both natural and engineered amino acids. This opens up endless possibilities for engineering silk with even greater strength and versatility. The field of spider silk production is ripe for exploration, and the remarkable mechanical properties of the fibers produced in this study hold great promise for various industries.
The successful creation of these bionic silkworms marks a significant milestone in the quest for sustainable and high-quality natural fibers. With further advancements and large-scale commercialization on the horizon, the potential of spider silk as a strategic resource can be fully realized.
