Navigation Links
Corals turn to algae for stored food when times get tough
Date:5/13/2013

Researchers at EPFL present new evidence for the crucial role of algae in the survival of their coral hosts. Ultra-high resolution images reveal that the algae temporarily store nutrients as crystals, building up reserves for when supplies run low.

The relationship between corals and the microscopic algae they harbor is a classic example of biological symbiosis - the mutually beneficial interaction of two species. But crucial details regarding their relationship have remained elusive until now. Using state-of-the-art imaging techniques, Anders Meibom and his team of researchers in the Laboratory for Biological Geochemistry have found new evidence on the vital role algae play in helping corals survive in environments where nutrients are scarce. Their findings were published in the journal mBio on May 16, 2013.

"Coral reefs are the jungles of our oceans - hotspots of biodiversity that easily outcompete all other marine ecosystems," says Christophe Kopp, first-author of the publication. Coral bleaching occurs when the colorful algae abandon their coral host because of environmental strains like rising sea temperatures. On their own, corals struggle to survive in tropical waters where nutrients are scarce, and persistent starvation can have irreversible effects. While it is well known that algae help corals to assimilate certain nutrients, such as nitrogen from seawater, how this occurs, and to what extent the corals can get by on their own, are less clear.

To study how nitrogen-rich nutrients are taken up and processed by the corals and the algae that inhabit them, Meibom's research group teamed up with the Aquarium Tropicale Porte Dore in Paris to run a series of experiments. There, they fed the corals nitrogen-rich compounds labeled with a heavy nitrogen isotope that they could later trace in the lab. Every few minutes, they extracted bits of coral, which they fixed and analyzed with a state-of-the-art isotopic imaging instrument, a so-called NanoSIMS.

Next, they assembled a timeline of how the nitrogen is processed by the corals and their resident algae by lining up the images of the samples extracted at different times. A combination of electron microscopy and mass spectrometry allowed them to study with unprecedented precision into which cellular compartments the heavier nitrogen isotopes had been incorporated.

Crystal food banks

The research revealed that the corals depend strongly on the algae to extract sufficient nutrients from the water. This was particularly true when the corals were exposed to nitrate, a compound that they are unable to process and assimilate on their own.

But most interestingly, the scientists observed that the algae act as tiny food banks. Their images revealed that the algae temporarily store the nitrogen in the form of uric acid crystals a fact they later confirmed using crystallographic analysis. This way, the algae can stock up on nutrients when supply is abundant and draw on them when supply drops, leaching some out to their coral host.

Because coral reefs are at the foundation of immense economic activity, both as tourist magnets and as the habitats of some of the most productive fish populations, understanding their fate as the environment they inhabit changes is not only of ecological, but also of economic importance.


'/>"/>

Contact: Anders Meibom
anders.meibom@epfl.ch
41-216-938-014
Ecole Polytechnique Fdrale de Lausanne
Source:Eurekalert

Related biology news :

1. University of Miami geologists to address the mystery of an evolution gap in reef corals
2. LSU professor discovers how new corals species form in the ocean
3. How do corals survive in the hottest reefs on the planet?
4. How the purple and pink sunscreens of reef corals work
5. Heat-resistant corals provide clues to climate change survival
6. Scary news for corals -- from the Ice Age
7. Corals attacked by toxic seaweed use chemical 911 signals to summon help
8. Coral scientists use new model to find where corals are most likely to survive climate change
9. Viruses could be the key to healthy corals
10. Less is more for reef-building corals
11. Pacific islands may become refuge for corals in a warming climate, study finds
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/11/2016)... , Jan. 11, 2016  higi, the ... nearly 10,000 retail locations, web and mobile, today ... $40 million from existing investors. ... be devoted to further innovate higi,s health platform ... and web portal – including expanding services and ...
(Date:1/7/2016)... , Jan. 7, 2016 This BCC Research ... for biometric technologies and devices, identifying newer markets and ... various types of biometric devices. Includes forecast from 2015 ... Identify newer markets and explore the expansion of the ... Examine each type of biometric technology, determine its current ...
(Date:1/6/2016)... 6, 2016  Varam Capital, a provider of micro-finance ... to deliver advanced authentication solutions to their clients. Varam ... poor. A loan of a few thousand rupees may ... the ability to purchase livestock or equipment for a ... stock for a local store. ...
Breaking Biology News(10 mins):
(Date:2/5/2016)...  In the pharmaceutical industry the medical affairs function ... activities including the identification and engagement of key thought ... high in the oncology therapeutic area where most treating ... Role of Medical Affairs in Oncology Launch Excellence ." ... find better ways to utilize medical affairs to develop ...
(Date:2/4/2016)... New FDA action date of July 22, 2016   ... 22, 2016   --> - New FDA ... - Lifitegrast has the potential to be the only product approved ... and symptoms of dry eye disease in adults --> - ... the U.S. in the past decade indicated for the treatment of signs and ...
(Date:2/4/2016)... 2016  CytoSorbents Corporation (NASDAQ: CTSO ), ... CytoSorb® blood filter to treat deadly inflammation in ... announced that CEO Dr. Phillip Chan , ... Group,s 2016 Disruptive Growth & Healthcare Conference, providing ... Conference Presentation Details: Where: Convene Conference ...
(Date:2/4/2016)... 2016 Sinovac Biotech Ltd. ("Sinovac" or the ... biopharmaceutical products in China , today ... directors received on February 4, 2016 a preliminary non-binding ... comprised of PKU V-Ming ( Shanghai ) ... Qianhai Development ( Shenzhen ) Fund Management ...
Breaking Biology Technology: