Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

All Decked Out

01.12.2009
Networks of chitin filaments are integral components of diatom silica shells

A whole microcosm of various bizarrely shaped life forms opens up when you look at diatoms, the primary component of ocean plankton, under a microscope.

The regularly structured silica shells of these tiny individual life forms have attracted scientists because they are particularly interesting examples of natural hybrid materials and also demonstrate unusual mechanistic and optical properties. The mechanisms of the underlying biomineralization process are not yet fully understood, but the silica shells often provide inspiration for the synthesis of man-made nanostructures.

Researchers at TU Dresden and the Max Planck Institute the Chemical Physics of Solids in Dresden have now identified another component of the diatom cell walls. As the team led by Eike Brunner reports in the journal Angewandte Chemie, they found an organic network of crosslinked chitin filaments.

Chitin is a long molecular chain of sugar building blocks, a polysaccharide. It is the second most widespread polysaccharide on Earth after cellulose. In combination with calcium carbonate (lime) and proteins, it forms the shells of insects and crabs. “Chitin plays an important role in the biomineralization of such calcium carbonate based shells and structures,” explains Brunner. “We have now been the first to demonstrate that the silica cell walls of the diatom Thalassiosira pseudonana also contain a chitin-based network.”

The researchers dissolved the silica components of diatom shells with a fluoride-containing solution. What remained behind appears under a scanning electron microscope as a delicate, net-like scaffolding. This network resembles the cell wall in form and size and consists of crosslinked fibers with an average diameter of about 25 nm. Spectroscopic examinations show that the fibers contain chitin and other, previously unknown biomolecules.

“Our results suggest that the chitin-based network structure serves as a supporting scaffold for silica deposition, while the other biomolecules actively influence it,” states Brunner. “This mechanism is thus analogous to calcium carbonate biomineralization. In addition, these networks may also mechanically stabilize the cell walls.”

Author: Eike Brunner, TU Dresden (Germany), http://analyt.chm.tu-dresden.de/

Title: Chitin-Based Organic Networks—An Integral Part of Cell Wall Biosilica in the Diatom Thalassiosira pseudonana

Angewandte Chemie International Edition, doi: 10.1002/anie.200905028

Eike Brunner | Angewandte Chemie
Further information:
http://analyt.chm.tu-dresden.de/
http://pressroom.angewandte.org

More articles from Life Sciences:

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

nachricht Stingless bees have their nests protected by soldiers
24.02.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>