Spider silk

Spider Silk

What exactly IS spider silk?

By comparison of size and density, spider silk is much stronger than steel and possesses an elastic property, thus giving it a very high energy-to-break ratio. In fact, the biopolymer structure of the silk is so strong, it is true to imagine the likes of a strand the size of a pencil being able to successfully stop and hold fast a commercial jet in flight! To date, spider silk is the strongest known material to man and synthetic materials cannot hope to even come close. The protein- and biopolymer-based material differs across the over 35,000 species of spiders, and is easily recyclable.

The proteins in the silk are complex molecules of amino acid. This, coupled with the spider's preference - as a predatory animal - for isolation from other species, has made the study and replication efforts of this magical superfiber quite challenging. It is so difficult to decode[?], the silk from only 14 species has been decoded; 10 of which since 2001 through a collaborated study between the University of California at Riverside[?] and the University of Wyoming[?].

How does the spider make the silk?

The thread is released through silk glands. Many species of spider have different glands[?] for different jobs, such as housing and web[?] construction, defense, capturing and detaining prey[?], mobility and in extreme cases even as food. Thus, the silk needs to be specialized for the task at hand so success is guaranteed.

The gland's visible, or external, part is termed the spinneret[?]. Depending on the species, spiders will have any number of spinnerets[?], usually in pairs. The beginning of the gland is rich in sulfhydryl and tyrosine groups, the main ingredient to silk fiber. After this beginning process, the ampulla[?] acts as a storage sac for the newly created fibers. From there, the spinning duct effectively removes water from the fiber and through fine channels also assists in its formation. Lipid secretions take place just at the end of the distal limb of the duct, and proceeds to the valve. The valve is believed to assist in rejoining broken fibers, acting much in the way of a helical pump.

External Links

Artificial Spider Silk (http://publish.investorlook.net/investorlook-com/web/irpages/client-sites/nexia/companynewsreleases.cfm?newsID=1088&companyID=31&companyLogo=nexia.gif) - An interesting article on a Canadian-based biotechnologies firm that has, in conjunction with the U.S. Army, spun the World?s first man-made spider silk performance fibers.

The Silk Gland (http://hubcap.clemson.edu/~ellisom/biomimeticmaterials/files/spiderbiology.htm) - A very nice breakdown of the silk gland[?], its parts and uses with images and drawings.

Spiders in Space (http://lsda.jsc.nasa.gov/scripts/cf/exper.cfm?exp_index=428) - NASA article and database information on the research of spiders in space.

Living Museum - The Spiders (http://www.wettropics.gov.au/lm/the_spiders.htm) - Excellent resource on primitive and new world species categorized by their hunting tactics.