Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Amphibian Froth

06.10.2008
Unusual linkage pattern in a blue protein found in the foam nests of tropical frogs

An unusual blue protein called ranasmurfin and found in the foam nests of a Malaysian tree frog has aroused the interest of a team of British, Brazilian, and Malaysian researchers led by Alan Cooper at the University of Glasgow and James H. Naismith at the University of St Andrews. The colored portion of the protein contains a previously unknown type of zinc-coordinated linkage between its subunits.

Many tropical frogs protect their sensitive eggs and embryos with a foam. When mating, the female excretes a protein-rich fluid that she, together with the male, whips into a sticky foam nest that is then stuck to a structure or plant overhanging a body of water. These tiny ecosystems contain an entire spectrum of previously unknown proteins and other macromolecules; they stabilize the foam, hold it firmly to its substrate, protect it from microbes and predators, prevent dehydration, and provide an ideal environment for the embryos.

The dark greenish-blue color of the nests of the Malaysian tree frog stems from ranasmurfin. Each monomer of this dimeric protein consists of 113 amino acids that are folded into a novel helical motif and stabilized through a series of cross-linkages, which includes an unusual lysine–tyrosine–quinone linkage. Even more unusual is the linkage between the two monomers, in which two lysine–tyrosine–quinone linkages are bridged by a nitrogen atom. This previously unknown type of linkage forms, together with two histidine groups, the binding site for a zinc ion. With its four ligands, the metal ion is thus in a tetrahedral environment. This structure is the unit responsible for the color (chromophore) of the protein.

Currently, the biological function of ranasmurfin can only be speculated. The scientists believe that this protein, which is present in relatively large amounts in the foam, is involved in the stabilization and adhesion of the foam. Proteins with similar linkages seem to play a role in the stabilization of adhesives and cements from mussels. Blue proteins are rare in nature and the chromophore in ranasmurfin has little in common with other blue-green proteins. The blue color could play a role in camouflaging the nests or protection from the sun.

Biological foams are an interesting source of novel proteins. Unusual variations, such as the linkages in the ranasmurfin chromophore, are often posttranslational, meaning they occur after translation of the genetic code into an amino acid chain, and are thus not predictable by the analysis of DNA sequences alone.

Author: Alan Cooper, University of Glasgow (UK), http://www.chem.gla.ac.uk/staff/alanc/

Title: Unusual Chromophore and Cross-Links in Ranasmurfin: A Blue Protein from the Foam Nests of a Tropical Frog

Angewandte Chemie International Edition 2008, 47, No. 41, 7853–7856, doi: 10.1002/anie.200802901

Alan Cooper | Angewandte Chemie
Further information:
http://pressroom.angewandte.org
http://www.chem.gla.ac.uk/staff/alanc/

More articles from Life Sciences:

nachricht Microscope measures muscle weakness
16.11.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg

nachricht Good preparation is half the digestion
16.11.2018 | Max-Planck-Institut für Stoffwechselforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Purdue cancer identity technology makes it easier to find a tumor's 'address'

16.11.2018 | Health and Medicine

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>