Scientists want to understand the molecular structure of different types of spider silks in order to engineer artificial silk that could be used for a broad range of medical and industrial applications. These include artificial tendons and ligaments, biodegradable fishing lines, parachute cords, and bulletproof vests.
"First, we really have to understand how these things work," said Ward Wheeler, curator of invertebrates at the American Museum of Natural History in New York.
"As we understand how these [spider silks] are structured, we can talk about perhaps engineering them to either amplify desirable properties or perhaps minimize other, less desirable properties," he said.
Individual spider species are capable of making different types of silks, which have different functional purposes.
Tubuliform glands, located in female spiders' abdomens, produce the fibers used to construct egg cases. But not all species' cases look the same. Black widow spiders, for example, produce an egg case that looks like a white, fluffy ball. Other spider species make egg cases that are flattened.
"The egg case silk protein is very different [from other proteins], and it appears to be exclusively used for constructing these egg cases," Garb said.
Scientists do not know much about the mechanical properties of egg case silk. But Garb hypothesizes that it might have unique properties based on its ability to protect hundreds of eggs. One possible trait, Garb notes, is the ability to block ultraviolet radiation, which could be useful for future spider silk applications.
Many more spider silk genes are waiting to be found.
As Wheeler, of the American Museum of Natural History, noted, there are "hundreds of million of years of biological experimentation in the tens of thousands of spider species we have today."
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