Scientists have long marveled at spider silk for its feather-like weight yet steel-like strength. There have been numerous attempts to produce the material commercially but they have, up until recently, been too expensive to be commercially viable.
Bolt Threads, a student-founded startup, has been at it for five years and is finally ready to go to market with the magically flexible and durable material that’s in some ways as strong as steel.
The company has developed a synthetic alternative to spider silk by engineering proteins identical to the natural threads spun up every day by spiders. Thanks to $40 million in funding from Silicon Valley heavyweight VC firms Foundation Capital, Formation 8, and Founders Fund those proteins will soon be turned into fabric.
“Over the past few decades, as clothing companies squeezed on price, they've taken the innovation out of apparel,” says Dan Widmaier, Bolt’s chief executive officer.
Widmaier along with co-founders Ethan Mirsky and David Breslauer are genetically modifying yeast to get them to excrete silk-like proteins.
“What would have been done in cells of spiders is now being done by yeast in our lab,” Widmaier says.
Investors are betting this material will rival the creation of petroleum-based fibers such as polypropylene and lycra. The former is lightweight and breathable but a breeding ground for smelly bacteria while lycra is thin and stretchy, but wears out easily.
By fiddling with the genetic makeup of the yeast cells Bolt can engineer fabrics to specific levels of softness, durability, and strength. “Our investing hypothesis was to make tunable silk that is hyperelastic and machine-washable,” says Steve Vassallo, a general partner at Foundation Capital, who invested in the company in 2011.
Back then, Bolt Threads was called Refactored Materials and had scientific rather than commercial goals. Widmaier was studying how to make proteins from yeast cells when he met Breslauer, a Ph.D. student at UC Berkeley, who was looking at how to process spider silk into fibers. They were operating on grants from the U.S. Army and the National Science Foundation to research yeast-made proteins and evaluate uses in ballistics—possibly to replace Kevlar in bulletproof vests—and materials such as surgical sutures. The most lucrative opportunity was right in front of them; Widmaier’s wife is a fashion designer at Old Navy, and the founders realized they could pitch their synthetic silk as an alternative to petroleum-based textiles such as polyester or cheap but non-eco-friendly staples like cotton.
Bolt Threads' office contains the usual conference rooms and lounges but also commercial grade centrifuges used to filter out the silk from the liquid. A larger room will soon hold 200-liter fermentation units for producing silk in greater quantities while Bolt is working with the Michigan Biotechnology Institute in Lansing to do larger-scale fermentation in 4,000-liter tanks. Unifi, a yarn manufacturer based in Greensboro, N.C., has been contracted to spin Bolt’s fibers into apparel-ready yarn and textiles.
The company expects to have high-performance sports shirts and bras using the material by late next year. Sue Levin, the founder of athletic wear retailer Lucy Activewear, to lead merchandising and marketing.
Though that strategy is a bit controversial, as the decision becomes whether to make its own clothes or provide the fabric to other apparel makers, or both.
The co-founders don't seem to have that part figured out and have both hired Ms Levin and are also talking to a major apparel brand about using the fabric
They don't have much time, either, as rivals at Massachusetts Institute of Technology are using bioengineered yeast for similar uses in apparel and medicine, such as artificial heart tissue.
Which is all good news for consumers. Within the next two years we'll see the spider-silk type material hit the market. If it lives up to its promises we'll see big apparel companies like Nike, Lululemon, Adidas and others quickly jump on the bandwagon.
And that should just be the start. Once the process if figured out on low-grade applications like fabric, you'll see more advanced forms of the material work its way into medical devices and other high-tech applications.