Not only are global landfills reaching their limits as the world’s growing population inundates it with waste, fast fashion is compounding the problem.
The History Behind the Fabric
While silk maintained its high-society status over thousands of years, the demand for easy-to-use materials grew among mass consumers. In the early 20th century, textile developers with new technological breakthroughs found synthetic materials: petrochemical-based polymer blended textiles with improved durability, strength and convenience.
According to the TS Digest in Science Daily, today, the textile industry is witnessing a new kind of synthetic revolution, one that paradoxically advocates bringing back natural materials. Synthetic biologists are using natural systems to produce materials with enhanced features to usher in an era of sustainable fashion.
Enter the Scientists
In their quest to make silk powerful again, not by status, but rather by thread strength, scientists turned to an arachnoid. Dragline silk, the thread by which the spider hangs itself from the web, is one of the strongest fibres; its tensile strength—a measure of how much a polymer deforms when strained—is almost thrice that of silkworm silk.2
Beyond durable fashion garments, tough silk fibres are coveted in parachutes, military protective gear and automobile safety belts, among other applications, so scientists are keen to follow these threads. While traditional silk production relies on sericulture, arachnophobes can relax: spider farms are not planned for the future.
The way to imitate spider silk webs is to make microbes matching this protein – David Breslauer, cofounder and chief technology officer at Bolt Threads, a bio apparel company.
Following the Thread
Researchers have tweaked microbes into churning their metabolites in large fermentation tanks, which they have harvested to solve dire crises in many areas. When pharmaceutical companies battled to meet the growing demand for insulin, researchers at Genentech sought the aid of E. coli to generate recombinant insulin for mass production in 1978.
Replicating the spider’s silk protein, spidroin, is not as easy for human not matter how smart our scientists are. Bulky proteins impose a heavy metabolic load on the microbes and their production yield tanks. Also, spidroin consists of repeating regions of glycine and alanine amino acids that impart strength and elasticity to the material, but the host microbes struggle with protein folding and overexpression of the corresponding tRNA molecules.
Enter the Scientific Pioneers
Eleven years ago Fuzhong Zhang, a synthetic biologist at Washington University in St. Louis, read an article about the challenges of spider silk protein synthesis. Zhang, who had just opened his own lab after working on metabolic engineering during his postdoctoral research with synthetic biology pioneer Jay Keasling at the University of California, saw potential in the project.
At the time, researchers had gotten close, but they hadn’t been able to synthesize the full spidroin protein. Since the molecular weight of the silk protein correlates with the strength of the silk thread, Zhang was determined to produce the entire protein to mimic the silk’s natural properties.
Zhang and his cohorts eventually allowed the team at Bolt threads to develop Micro silk, a spider inspired biomaterial but the initial yield was according to Zhang, not even enough to make one shirt.
Scientists Doing What They Do Best
And being scientists, they tweaked and tinkered and voila, a functional spidroin mimic saw the light. It was also during this time that David Breslauer, of Bolt Threads realised the demand for innovation in the textile space.
Putting their scientific and business minds together, these pioneers challenged the status quo and the market took to it like a spider to its own web. Their persistence paid off and their innovation is finding a foothold in the cosmetic industry as well. We may very well soon look younger as the next step is tackling the collagen issue which could maybe in the future be produced from yeast.
The fashion industry has embraced the new and the call to save the planet as scientists and visionaries match the best of material science with the best of synthetic biology.
