Featured Research

from universities, journals, and other organizations

Fascinating Spider Silk

Date:
April 6, 2007
Source:
John Wiley & Sons, Inc.
Summary:
Spider silk would be an ideal material for a large variety of medical and technical applications, and researchers are thus interested in learning the spiders' secrets and imitating their technique. Scientists report that the interaction between hydrophilic and lipophilic properties of the silk proteins plays an important role in the spinning process.

Stronger than steel and more elastic than rubber: spider silk is unsurpassed in its expandability, resistance to tearing, and toughness. Spider silk would be an ideal material for a large variety of medical and technical applications, and researchers are thus interested in learning the spiders’ secrets and imitating their technique.

A team lead by Thomas Scheibel at the Technical University of Munich has now made a step in the right direction. As they report in the journal Angewandte Chemie, the interaction between hydrophilic (water friendly) and lipophilic (fat friendly) properties of the silk proteins plays an important role in the spinning process.

Fundamentally, the spinning of spider silk represents a phase change from a solution into a solid thread; but the exact details of this process are largely unknown. The silk used by orb weaver spiders to spin the edges and spokes of their webs and to rappel away in the face of danger is made of two different proteins. The Munich team has now successfully used genetic engineering to produce one of the spider silk proteins of the European garden spider (Araneus daidematus).

While purifying the protein by dialysis, the researchers observed the separation of two different fluid phases. Whereas one phase consisted of protein dimers, the second consisted of oligomers—multiple protein units linked together. After the addition of potassium phosphate, a natural initiator of silk aggregation, the liquid could be pulled into threads. “It is clearly not a structural change in the protein, but rather the degree of oligomerization that is crucial for thread formation,” concludes Scheibel.

The silk solution in the spider’s silk gland has a very high protein concentration. This solution also contains a high concentration of sodium chloride, which suppresses oligomer formation. If the sodium chloride is removed, the proteins aggregate into oligomers.

In addition, the pH value also plays a crucial role in web production: within the silk gland, the pH is relatively high, but within the spinning duct it drops to a slightly acidic level. No phase separation was observed for the synthetic spider protein when the pH was maintained at an alkaline level. At high pH, the normally uncharged tyrosine groups in the protein are deprotonated, which gives them a negative charge. This charge weakens the interactions between the hydrophobic, lipophilic regions of the proteins, which are necessary for oligomerization.

“Our insights form a foundation for the establishment of an effective spinning process for the production genetically engineered spider silk,” hopes Scheibel.


Story Source:

The above story is based on materials provided by John Wiley & Sons, Inc.. Note: Materials may be edited for content and length.


Cite This Page:

John Wiley & Sons, Inc.. "Fascinating Spider Silk." ScienceDaily. ScienceDaily, 6 April 2007. <www.sciencedaily.com/releases/2007/04/070405094039.htm>.
John Wiley & Sons, Inc.. (2007, April 6). Fascinating Spider Silk. ScienceDaily. Retrieved September 22, 2014 from www.sciencedaily.com/releases/2007/04/070405094039.htm
John Wiley & Sons, Inc.. "Fascinating Spider Silk." ScienceDaily. www.sciencedaily.com/releases/2007/04/070405094039.htm (accessed September 22, 2014).

Share This



More Plants & Animals News

Monday, September 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: San Diego Zoo Welcomes Cheetah Cubs

Raw: San Diego Zoo Welcomes Cheetah Cubs

AP (Sep. 20, 2014) The San Diego Zoo has welcomed two Cheetah cubs to its Safari Park. The nearly three-week-old female cubs are being hand fed and are receiving around the clock care. (Sept. 20) Video provided by AP
Powered by NewsLook.com
Chocolate Museum Opens in Brussels

Chocolate Museum Opens in Brussels

AFP (Sep. 19, 2014) Considered a "national heritage" in Belgium, chocolate now has a new museum in Brussels. In a former chocolate factory, visitors to the permanent exhibition spaces, workshops and tastings can discover derivatives of the cocoa bean. Duration: 01:00 Video provided by AFP
Powered by NewsLook.com
Could Grief Affect The Immune Systems Of Senior Citizens?

Could Grief Affect The Immune Systems Of Senior Citizens?

Newsy (Sep. 19, 2014) The study found elderly people are much more likely to become susceptible to infection than younger adults going though a similar situation. Video provided by Newsy
Powered by NewsLook.com
Jury Delivers Verdict in Salmonella Trial

Jury Delivers Verdict in Salmonella Trial

AP (Sep. 19, 2014) A federal jury has convicted three people in connection with an outbreak of salmonella poisoning five years ago that sickened hundreds of people and was linked to a number of deaths. (Sept. 19) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins