Scientists unravel the mysterious mechanics of spider silk

March 1, 2011, Cell Press

Scientists now have a better understanding of why spider silk fibers are so incredibly strong. Recent research, published by Cell Press on February 15th in Biophysical Journal, describes the architecture of silk fibers from the atomic level up and reveals new information about the molecular structure that underlies the amazing mechanical characteristics of this fascinating natural material.

Spiders spin silk, which is remarkably strong and stretchy, to use in webs and to suspend themselves. "Silk fibers exhibit astonishing . They have an ultimate strength comparable to steel, toughness greater than Kevlar and a less than cotton or nylon," explains senior study author Dr. Frauke Gräter from the Heidelberg Institute for Theoretical Studies in Germany. "Because silk fibers continue to outperform their artificial counterparts in terms of toughness, many studies have tried to understand the mechanical characteristics of these extraordinary natural fibers."

Scientists know that spider silk fibers consist of two types of building blocks, soft amorphous and strong crystalline components. Dr. Gräter's group wanted to develop a better understanding of the mechanical properties of spider silk fibers and implemented a multi-scale "bottom-up" computational approach that started at the level of the atoms that make up the amorphous and crystalline subunits and dissected the contributions of these building blocks. The group used both molecular simulations for studying individual and coupled subunits and finite element simulations for a comprehensive fiber model.

The researchers discovered that the soft amorphous subunits are responsible for the elasticity of silk and also help with the distribution of stress. The maximal toughness of silk requires a specific amount of crystalline subunits and is dependent on the way that these subunits are distributed in the fiber. Different structural architectures of the fiber subunits were tested for optimal mechanical performance.

"We determined that a serial arrangement of the crystalline and amorphous subunits in discs outperformed a random or parallel arrangement, suggesting a new structural model for silk," says Dr. Gräter. Taken together, the findings provide a clearer understanding of the mechanical nature of fibers and may be useful for design of artificial silk fibers.

Explore further: Scientists genetically engineer silkworms to produce artificial spider silk (w/ Video)

Related Stories

Stretchy spider silks can be springs or rubber

May 31, 2008

It’s stronger than steel and nylon, and more extensible than Kevlar. So what is this super-tough material? Spider silk; and learning how to spin it is one of the materials industries’ Holy Grails. John Gosline has been ...

Scientists breed goats that produce spider silk

May 31, 2010

(PhysOrg.com) -- Researchers from the University of Wyoming have developed a way to incorporate spiders' silk-spinning genes into goats, allowing the researchers to harvest the silk protein from the goats’ milk for a variety ...

Recommended for you

Walking crystals may lead to new field of crystal robotics

February 23, 2018

Researchers have demonstrated that tiny micrometer-sized crystals—just barely visible to the human eye—can "walk" inchworm-style across the slide of a microscope. Other crystals are capable of different modes of locomotion ...

Researchers turn light upside down

February 23, 2018

Researchers from CIC nanoGUNE (San Sebastian, Spain) and collaborators have reported in Science the development of a so-called hyperbolic metasurface on which light propagates with completely reshaped wafefronts. This scientific ...

Recurrences in an isolated quantum many-body system

February 23, 2018

It is one of the most astonishing results of physics—when a complex system is left alone, it will return to its initial state with almost perfect precision. Gas particles, for example, chaotically swirling around in a container, ...

Seeing nanoscale details in mammalian cells

February 23, 2018

In 2014, W. E. Moerner, the Harry S. Mosher Professor of Chemistry at Stanford University, won the Nobel Prize in chemistry for co-developing a way of imaging shapes inside cells at very high resolution, called super-resolution ...

Hauling antiprotons around in a van

February 22, 2018

A team of researchers working on the antiProton Unstable Matter Annihilation (PUMA) project near CERN's particle laboratory, according to a report in Nature, plans to capture a billion antiprotons, put them in a shipping ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.