The new gene makes the spider silk super tough

darwin bark spider silk has extraordinary toughness. A recent paper published in Communications-Biology reported a new gene that may explain this toughness. The discovery may have implications for the design of new biological materials.
can weave the largest known round web, up to 25 metres long. The traction wire used by Darwinian bark spiders to construct the contours of cobweb structures is the most powerful biological material known and is 10 times more resilient than synthetic fibers. But why the spiders have such extreme toughness( the properties used to measure strength and scalability) remains unknown.
Jessica Garb of the University of Massachusetts at Lowell and colleagues sequenced the genes expressed in Darwin's bark spider glands and found an unusual spider gene. Although Darwin bark spiders produce the same primary spider protein as other spiders, they also produce a protein with a unique repeat sequence. The sequence contains a large amount of proline, an amino acid known to make spider silk more elastic. The researchers believe this unique protein sequence makes Darwin's bark spiders so resilient. (Source: Jin Nan, China Science Journal)
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