Featured Research

from universities, journals, and other organizations

How soft corals defy their environment: Protein favors calcite formation in aragonite sea

Date:
August 16, 2011
Source:
Ludwig-Maximilians-Universitaet Muenchen (LMU)
Summary:
Many marine organisms, including corals, build skeletons from calcium carbonate – in the form of calcite or aragonite. The current composition of seawater favors the formation of aragonite – but soft corals have a specific protein that allows them to form calcite skeletons instead.

Many marine organisms, including corals, build skeletons from calcium carbonate -- in the form of calcite or aragonite. The current composition of seawater favors the formation of aragonite -- but soft corals have a specific protein that allows them to form calcite skeletons instead.

Calcium carbonate is a salt for all seasons. It turns up not only in marble, but also in biogenic sediments such as limestone and coral reefs -- and even in pearls. The compound exists in two major crystalline forms, as calcite or aragonite. However, it is not clear what determines which variant an organism will exploit under conditions in which both forms can precipitate.

A team of researchers led by LMU geobiologist Dr. Azizur Rahman, who is also a Research Fellow of the Alexander von Humboldt Foundation, has now answered this question, in collaboration with colleagues based at the University of the Ryukyu Islands in Japan.

Together, the scientists have shown that, in the soft coral species Lobophytum crissum, a secreted, extracellular protein known as ECMP-67 is the decisive factor that results in the precipitation of calcite, irrespective of the chemical conditions prevailing in the surrounding seawater.

"Over the course of Earth's history, and most probably depending on the relative amounts of dissolved magnesium and calcium ions, either calcite or aragonite has dominated in the world's oceans," says Professor Gert Wφrheide, one of the authors of the new study. Current conditions favor the formation of aragonite, and many stony corals build their skeletons exclusively from this material. However, thanks to ECMP-67, Lobophytum crassum can still produce calcite in an aragonite sea.

"We have also been able to show how the extracellular protein ECMP-67 contributes to the production of calcite at the molecular level," says Rahman. "These findings should also allow us to elucidate the crystal structure of calcite in natural environments."

The study was funded by the Alexander von Humboldt Foundation and the Japanese Society for the Promotion of Sciences.


Story Source:

The above story is based on materials provided by Ludwig-Maximilians-Universitaet Muenchen (LMU). Note: Materials may be edited for content and length.


Journal Reference:

  1. A. Rahman, T. Oomori, G. Woerheide. Calcite formation in soft coral sclerites is determined by a single reactive extracellular protein. Journal of Biological Chemistry, 2011; DOI: 10.1074/jbc.M109.070185

Cite This Page:

Ludwig-Maximilians-Universitaet Muenchen (LMU). "How soft corals defy their environment: Protein favors calcite formation in aragonite sea." ScienceDaily. ScienceDaily, 16 August 2011. <www.sciencedaily.com/releases/2011/08/110816120828.htm>.
Ludwig-Maximilians-Universitaet Muenchen (LMU). (2011, August 16). How soft corals defy their environment: Protein favors calcite formation in aragonite sea. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2011/08/110816120828.htm
Ludwig-Maximilians-Universitaet Muenchen (LMU). "How soft corals defy their environment: Protein favors calcite formation in aragonite sea." ScienceDaily. www.sciencedaily.com/releases/2011/08/110816120828.htm (accessed October 20, 2014).

Share This



More Plants & Animals News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Rare Lion Cubs Make Debut at Belgrade Zoo

Raw: Rare Lion Cubs Make Debut at Belgrade Zoo

AP (Oct. 17, 2014) — Two white lion cubs were born in Belgrade zoo three weeks ago. White lions are a rare mutation of a species found in South Africa and some cultures consider them divine. (Oct. 17) Video provided by AP
Powered by NewsLook.com
The Best Foods To Boost Your Mood

The Best Foods To Boost Your Mood

Buzz60 (Oct. 17, 2014) — Feeling down? Reach for the refrigerator, not the medicine cabinet! TC Newman (@PurpleTCNewman) shares some of the best foods to boost your mood. Video provided by Buzz60
Powered by NewsLook.com
Sweet Times for Hard Cider Makers

Sweet Times for Hard Cider Makers

AP (Oct. 16, 2014) — With hard cider making a hardcore comeback across the country, craft makers are trying to keep up with demand and apple growers are tapping a juicy new revenue stream. (Oct. 16) Video provided by AP
Powered by NewsLook.com
Meet Garfi the Angry Cat

Meet Garfi the Angry Cat

Buzz60 (Oct. 16, 2014) — Garfi is one frowny, feisty feline - downright angry! Ko Im (@koimtv) introduces us to the latest animal celebrity taking over the Internet. You can follow more of Garfi's adventures on Twitter (@MeetGarfi) and Facebook (Garfi). Video provided by Buzz60
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:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

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