Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Findings on Spider Silk

15.11.2013
Spider silk fibers are very light, extremely tough and highly stretchable. This makes them interest-ing for industrial applications. Researchers at the Biocenter of the University of Würzburg have now discovered new details about the proteins of which spider silk consists.

Spider webs are made from a fascinating material. The eight-legged critters produce it in the silk glands on their abdomen from special proteins, which are spun into long threads. This can be done extremely fast: For a quick descent, for instance, they extrude the silk threads with a speed of up to one meter per second.


A garden spider pulls silk threads with its legs from the spinnerets on the abdomen.
(Photo: Manfred Schwedler)


The rapid production of silk threads in spiders involves unusual electrostatic interactions between the proteins.

(Graphics: Hannes Neuweiler)

However, the silk-spinning speed of the spiders is not the only impressive thing – the intrinsic properties of the material are no less astonishing: "Taking into account its lightness in a weight-for-weight comparison, a spider's dragline or the framework thread of a web is tougher than steel or even than the high-tech fiber Kevlar," explains Hannes Neuweiler at the Biocenter of the University of Würzburg.

Spider silk: many possible applications

It's no wonder that scientists and engineers try to emulate the production of spider silk technologi-cally in research laboratories and industrial facilities. There are many conceivable applications, rang-ing from novel fibers for high-performing textiles to innovative materials for vehicle construction or medical technology. Spider silk has the additional advantage of being biologically compatible with the human body and it is completely biodegradable.

"From a technological perspective, the production of spider silk works quite well already. So far, however, the outstanding mechanical properties of natural spider silk have not been attained in this way," says biotechnologist Neuweiler. And he knows a reason for this: We still do not understand the molecular mechanisms in the natural spinning process well enough to imitate them perfectly.

The dynamics of the spinning process shown

What the Würzburg researcher finds particularly fascinating about the spinning process is the speed with which individual protein molecules in the spider arrange themselves into long threads. He examined this aspect in greater detail – after all, his research team specializes in the visualization of protein dynamics. This research requires the application of special optical methods.

Neuweiler and his associates have now analyzed a certain section of a silk protein from the nursery web spider Euprosthenops australis. "This section is very interesting, because it connects the termi-nal areas of the proteins that link to form silk threads," says Neuweiler.

The presence of salt does not affect the speed of the protein linkage

The result is published in the journal "Nature Communications": The observed section links the proteins 1000 times faster than is usual in common protein-protein interactions. In addition, there is another striking feature: The presence of salts does not slow down the process, which is generally the case in such fast protein interactions. The researchers explain this phenomenon with an electrical particularity of the examined protein section, namely its peculiar dipole-dipole interactions.

"With the silk production of spiders, evolution seems to have found a way of greatly accelerating the association of proteins even in the presence of physiological concentrations of salt," explains Neuweiler. This is necessary because the silk gland contains several varieties of salts at the end of the spinning duct, where the silk protein fibers are generated, which salts play some role in the spinning process. Their precise function, however, is still poorly understood.

Further exploration of the phenomenon

The Würzburg biotechnologists are now scrutinizing this "salt resistance" further. Next, the researchers are going to determine whether this phenomenon also occurs with other spider silk proteins in other types of silk glands, as spiders have up to seven such silk glands in their abdomen, with which they can produce different kinds of silk.

Publication

The N-terminal domains of spider silk proteins assemble ultrafast and protected from charge screening, Nature Communications, 2013, November 15, DOI 10.1038/ncomms3815

Contact person

Dr. Hannes Neuweiler, Department for Biotechnology and Biophysics, Biocenter at the University of Würzburg, T +49 (0)931 31-83872, hannes.neuweiler@uni-wuerzburg.de

Robert Emmerich | Uni Würzburg
Further information:
http://www.uni-wuerzburg.de

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Global study of world's beaches shows threat to protected areas

19.07.2018 | Earth Sciences

New creepy, crawly search and rescue robot developed at Ben-Gurion U

19.07.2018 | Power and Electrical Engineering

Metal too 'gummy' to cut? Draw on it with a Sharpie or glue stick, science says

19.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>