EMERYVILLE, Calif. — Clothing and spiders go all the way back to Greek mythology, in which the arrogant weaver Arachne is turned into a spider by the goddess Athena after challenging her to a weaving competition.
But today, technology has taken over the role of both spider and weaver at Emeryville-based Bolt Threads, which produces proteins that are fermented and then spun into fibers that can be used in modern clothing.
Co-founded by Dan Widmaier and David Breslauer in 2009, Bolt last year purchased New York City-based outdoors company Best Made Company and closed a $123 million round of Series D funding.
We sat down in the lab with Breslauer, who also serves as chief science officer, to talk about Bolt’s process, and its past, present and future. This interview has been edited for length and clarity.
Q: Can you walk through what it takes to make your spider silk?
A: When it comes to actually making fibers, the process itself is quite long. We take DNA sequences from nature, which we know create fibers that we see in spider webs or in silkworms. And then we take those sequences and we take them in a proprietary yeast that we brew up like beer. Those yeasts make the protein, and we purify it and extract it into threads. The extraction works with a shower head where a bunch of liquid jets come out and we solidify them through another proprietary process.
Q: I believe your fibers are recyclable too. Are there limits to what you can do with your fibers?
A: In the apparel market, the end is only in your imagination. Because we can design these proteins from scratch, we can add all sorts of functionalities into them, some of which might not be found in nature otherwise. We can turn silk into something that can be machine washable, for example. And our fibers are entirely protein so it’s all entirely recyclable.
Q: It sounds amazing, but your products are either $198 beanies or $314 neckties. Are you seeking to bring the price significantly down?
A: As with any new technology, it starts at a higher price point. As we develop consistency and quality and increase our manufacturing scale, these costs come down over time.
Q: You and your co-founders started this company in 2009. What have the past eight years been like?
A: I was studying spider silk since 2006, and I was then working on how to make miniaturized biology or chemistry labs — lab on a chip, it was called. I learned that the spider’s gland that makes the silk acts very much like one of these microdevices I was building. So I switched my entire effort from making a miniature biology or chemistry lab to making a microlab that was effectively a spider silk gland. The wall I hit was that I could make these fibers if I had silk but I didn’t have the silk precursors, but I was introduced serendipitously to two scientists at UCSF who fortuitously were making microorganisms to make the precursor but didn’t know how to make the fiber. So with our powers combined, we realized we had the whole package together.
We got some government grants the first year, and at that point we decided that we were going to stay quiet until we can deliver something. We really wanted to not over-promise and under-deliver. When we raised a Series A and Series B during that process, we were just working in the lab and growing the team and building it up. So there is a period of five years where we were building science and the organization but staying very quiet to the external world.
Q: Did it take longer to reach this level than you expected? What was the hardest part?
A: I think the science took longer than I thought. We learned a lot about scaling up and manufacturing and all the challenges in the way. All of these things take time and money. The hardest part was managing slow and steady tech progress as it was balanced with demonstrating progress. Sometimes you have to brute-force things to show we made progress to external eyes and investors. But that might bring on what we call technical debt because that’s not the most scalable way to do that. It’s like building a plane while flying it.
PROFILE
David Breslauer
Age: 34
Position: Chief Science Officer, Bolt Threads
Hometown: Oakland
Education: Ph.D. in Bioengineering from UC Berkeley and UCSF
Five facts about David Breslauer
—He gets his best ideas while running.
—He’s trained in Krav Maga, a military-style self-defense and fighting system developed for Israeli defense and security forces, for the last year.
—His favorite animal is the elephant.
—He lived in Paris for his sophomore year of high school.
—He initially wanted to be a professor before he joined the startup scene.
About the Author
