What Did You Do to Make the Spiders Produce the Same Proteins?

In order to produce synthetic spider silk, scientists have been attempting to recombinantly produce the proteins involved in silk production. Some attempts have been successful. However, they’re still not perfect. There are still several ambiguities regarding the composition and structure of the protein molecules.

Scientists have been able to produce artificial silk using bacteria. The result is an amino acid polymer that’s stronger than natural spider silk. This new protein fiber is stretchy and strong. But it’s not yet possible to replicate the spider’s spinnerets.

Researchers at Arizona State University have recently studied the molecular structure of the silk of spiders. They found that the proteins in spider silk are organized in a tight structure called a nanocrystal. These crystals span a few billionths of a meter.

The researchers discovered that the composition of the protein crystals in silk is similar to that in E. coli protein polymers. When the protein crystals clump together, they look like white cotton candy. Li and his team believe that these new protein fibers are both strong and stretchy.

Spiders use other silks for wrapping prey, as well as egg sacs. The proteins involved in the process are held in glands in the abdomen. Depending on which gland issues the protein, the spinning behavior of a spider can vary.

The researchers believe that if a spider can produce different protein molecules in response to the amino acids in its prey, the results could have consequences for the positive selection of silks with different structures.