Replies to post #94088 on Kraig Biocraft Laboratories Inc (KBLB)

[saintcalvus]

That's excellent DD in my book mojo. Thanks!

[Eskaminagaga]

I remember looking at this a while back. It is one of the reasons why I started looking into the E.coli producers with more scrutiny. From the PNAS article:

The 96-mer fiber exhibited the tenacity of 508 ± 108 MPa and elongation of 15 ± 5%, which are comparable with the values reported for native N. clavipes dragline silk (740–1,200 MPa; 18–27%). Notably, Young’s modulus of the 96-mer fiber was 21 ± 4 GPa, twice that of the native dragline silk (11–14 GPa).

It looked like they had already achieved near the same properties as native dragline silk (on the low end). This compared to KBLB's PNAS article showing the strains of Monster Silk™ having up to only 338.4 ± 87.0 Mpa of max stress showed that the previous PNAS article had a stronger fiber. Of course, Kim did state that these values had improved.

I had been betting on the presumptively cost prohibitive nature of producing fibers from bacteria and the fact that KBLB is initially aiming for the mundane clothing market for its success. If KBLB can bring their new Dragon Silk to commercialization in a timely enough manner, then they should have nothing to worry about unless Spiber Inc. and others can significantly reduce the assumed cost to produce their silks.

It is also worth noting a couple names on the study. Namely David Kaplan, one of the world's leading scientists in Spider Silk based out of Tufts University and founder of Cocoon Biotech Inc. and Sang Yup Lee, one of the head researchers at KAIST. I remember reading somewhere that Spiber Inc. and KAIST are working together, but I asked at the QMONOS™ display if they were to confirm it, but they could not confirm nor deny if this was true. They did state that Spiber Inc. was working alone up until after the QMONOS™ fibers were developed at which point they started working with others, though. Knowing this, I don’t think that they actually used this technology. I have reason to believe that Spiber Inc.’s fibers will have stronger properties than this at commercialization, anyway.

[rayovac812]

Were you asked to post this by someone? what don't you understand when they say "We also found that the proteins of lower molecular weight versions yielded inferior fiber properties." So we are correct in saying the exact same thing.

Apparently they are not sure if this process will work. the last line you quoted says that it should be useful for sustainable poroduction.

It is a good find. They have surpassed MS. Now other questions need to be answered. We both are looking for the upper limits for strength. If you read this carefully, you will have to admit the process does not repeat the properties of native SS. That is what it says and it is what it is. Maybe look up the word recapitulate.

[first mike]

i thought the synthetic spider silk companies couldnt make make big spider silk proteins...i also thought there was no pnas on anything they've done?...

btw, this was in 2010...

Yes Mojo, you are correct on both counts.
This research was new to me.
However; the same question needs to be asked of this KRAIST team as was asked by you of KBLB:
What have they done to move forward since 2010?
In this case moving toward production would be difficult because while they were able to separate some high MW protein from the mix, the vast majority of the proteins produced were of lower MWs which they classify as inferior.
My best estimate of the fraction of High MW protein producedis much less than 10% (and I am being generous) Look at the paper for confirmation.
They do not specifically state (that I saw) how the High MW protein was separated and purified but my best guess is that it was done either by ultracentrifuge or by liquid column chromatograpy.
Neither method would lend itself to production quantities.
As it stands, this is a laudable piece of research, but the tiny quantity of High MW protein produced has to be one of the most expensive per gram substances in existence, much more so than Amsilk's expensive product.

Thanks for your thoughtful comments!

Mike L.