Silk fibroin

Silkworms spin their cocoon out of fibroin. It packs into tight sheets, which is why silk thread is so strong.

Fun fact

Unwind one silkworm cocoon. You can get a single thread about a kilometer long, or longer.

Words to know

protein
fold

NGSS alignment

MS-LS1-2Inside the cell

Structure

AlphaFold has no 3D model of this protein. Silk fibroin's main chain is more than 5,000 amino acids long, and much of it is the same short pattern repeated again and again, which puts it outside what the AlphaFold Database covers. So there is nothing to spin in 3D here, and we would rather show you nothing than a wrong shape. UniProt entry: P05790.

For teachers and platforms

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