Spider Silk, Spider Silk, Made Using A Strain Of Yeast

Companies spend thousands developing a project for the market, hoping their investment will return big. Investing like this happens every day and won’t shock anyone. What may surprise you is someone who spends more than a decade and thousands of their own dollars to make an open-source version of a highly-marketable product. In this case, we’re talking about genetically modified yeast that produces spider silk. If that sounds like a lead-in to some Spiderman jokes and sci-fi references, you are correct on both accounts. [Justin Atkin] had some geneticist work under his belt when he started, so he planned to follow familiar procedures like extracting black widow DNA, isolating and copying the silk genes, and pasting them into a yeast strain. Easy peasy, right? Naturally, good science doesn’t happen overnight.

There are a few contenders for the strongest spider silk among which the golden silk orb-weaver gets the most attention, but the black widow’s webbing is nearly as strong, and [Justin] is happy to wear black widow inspired bling, whereas the golden orb-weaver looks like it crawled out of Starship Troopers. His first attempt to extract DNA starts with a vial of preserved nightmare fuel spider specimens because that is a thing you can just go online and buy. Sadly, they were candied in alcohol, and that obliterates DNA, so he moved to dried specimens from breeders, which also failed to produce results, and those were just the landmark hangups.

After all the setbacks and dead ends, [Justin] and his lab crew take a different path and design a plasmid-to-order. Sheesh, you can buy anything on the Internet. Labs that build these sequences aren’t like a custom T-shirt producer because you can’t just send them Gattaca.TXT and a check. The labs will refuse sequences with repetitious snippets, and spider silk is long repeating chains. [Justin] has to make his recurrent silk look unique all the way through, and so he has to tweak nature’s recipe.

Silk is not a singular thing but rather a classification of what comes from a spinneret. Spiders produce as many as ten varieties of silk, and they are a combination of monomers. Some are sticky, some are stretchy, and some are strong, but for commercially viable stuff, we are interested in dragline which is firm and not elastic. It is safe to assume this is what [Peter Parker] loads into his web slingers. The variety comes from ordering and reordering the stretchy-strong sequence to increase the variabilty, but that only goes so far. [Justin] adds a new contribution to the mix, and that comes in the form of biomineralization, which we see in things like nacre (mother of pearl), chitin, and bones. This is one of the sturdiest things mother nature put into animals, so the improved formula has a little extra strength in the mix. Another ingredient is the sequence to tell the yeast to excrete the silk, not just produce it internally. This makes harvesting the difference between milking a cow and butchering one.

When the lab’s plasmid arrives, they mix it into some pichia pastoris yeast which is normally pinkish, but the modified strain is bone white. It is a fickle strain and doesn’t want to accept the new genes, but Youtube commentators provided helpful protocols. This in itself is an achievement, as if you can get the YT comment section to provide useful data, you deserve a trophy. After the new procedures, a battery of tests shows that gene modification took hold. [Justin]’s yeast was producing silk at a respectable rate. Wow.

Now, the plan is to find ways to do something with the mass-producible silk. We love the idea of growing tough-as-nails cargo pants or black widow web-shooters. Spider senses not included.

25 thoughts on “Spider Silk, Spider Silk, Made Using A Strain Of Yeast

  1. I am too lazy to go the source, but is the material any good? Does it have to come out of the rear end of a spider to actuallly work?

    We are often told that spider silk is stronger than steel. But, then, Aluminium is stronger than steel if you choose the right steel and the right Aluminium. Is spider silk stronger than a similarly thin filament of piano wire? I don’t know if this has been considered in the comparisons, but size matters. I used to work in the field of fracture mechanics and a company I was collaborating with were using 1m wide “compact” test specimens ( https://en.wikipedia.org/wiki/Compact_tension_specimen ) because even very ductile materials can suffer brittle fracture at that scale and they were making huge pressure vessels.

    1. Why so much hate ? This guy’s channel is all about what
      biohacking you can do in a (well equiped) basement. You are attacking him because he doesn’t have the same goals or results requirement than a multi-million dollar funded research program? This is on YouTube, not published in Nature…

    2. Yeah but that is a fatigue test standard and fatigue failures are brittle failures.
      Is it stronger than piano wire? Yes, material strength is measured in stress per unit area.
      As the other chud commenter pointed out, there is a difference between strength and stiffness. But the article even says this experiment used the stiffest silk he had available.

  2. Some spiderweb is said to have antibiotic properties, I wonder if that could be a spin-off (sorry/notsorry) of this, or whether that’s the spider spit or something that they apply to it. Just saying because of the every-so-often “Eek we’re running out of antibiotics!!” thing,

    1. Honestly, my hopes are set on bacteriophages to solve the antibiotic resistance issue. It’s been shown that using bacteriophages is highly effective against antibiotic resistant stuff and when it becomes bacteriophage resistant it loses it’s antibiotic resistant properties. It might take until the end of the century but I look forward to getting a small injection which will then rewrite a bunch of cells to produce a huge variety of bacteriophages which explode out of the cells (suicidal production) and eradicate infections.

      1. This is relatively heavy used in russia because penicillin wasn’t availlable. The issue with phage therapy is, that it is quite risky. Afaik the stuff that makes the cell membranes collapse is developed in the US.

    2. Would spiderweb antibiotic activity occur only on surfaces, or could it actually be used inside humans? I would have thought it might be hard to get it into a human (orally or through injection) if you need significant lengths of the protein to be effective. If so, it still might be useful on surface wounds etc. I agree that we are definitely running out of effective antibiotics.

  3. Some 8 years or so ago, a geneticist cleaved the spider silk gene into a goat’s mammary glands. Suffice to say the milk had the monomer units which could then be extracted and polymerized into spider silk. It was I think a PBS documentary which also touched on the burgeoning amateur genetic engineering arena where kids could meet teachers and bring along their sequences to insert into benign E coli.

    Genetics with advanced computing looks like it will be the next big thing and not just for species re genetic conditions but, also treatments of so many kinds. Worth checking out Craig Ventur who made a more efficient bacterial nucleus on a machine from ACTG sequencer inserted into a “dead” phospholipid bubble, gave it a zap and voila it not only lives and replicates but more efficient than any other of the same type. He even put his email address into the DNA so if someone could decide it they can contact him etc

    1. I was reading the other month about some greenhouse gas capture with bacteria that had crappy efficiency, I wonder if nucleus 2.0 DOHC injection turbo GLHS edition would improve it.

  4. Interesting using Pichia pastoris for expression system. Originally developed and patented by Phillips Petroleum. Curious how glycosylation of the spider silk affects its properties. I would have thought that expessing the silk in insect cells would be closer to normal.

  5. “But, then, Aluminium is stronger than steel if you choose the right steel and the right Aluminium”

    … and the right definition of “strong”. Taken alone, “strong” is a pretty weak concept :-)

    1. [Justin] explains in the video. I’ll see if I can paraphrase. Since CRISPR relies on seeking out repeating segments for replacement, a long repetitious string is going to be prone to repeats in the wrong place and tricky or prone to failures.

  6. Sounds very promising and it is a great achievement to get as far as he has, but I can think of other similar projects that would have far more impact right now, then again you have to start somewhere…

  7. “we are interested in dragline which is firm and not elastic. It is safe to assume this is what [Peter Parker] loads into his web slingers.”

    And this is why Gwen Stacy is dead.

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