Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Canola study solves seed oil mystery

09.12.2004


Scientists from Michigan State University have uncovered a previously unknown metabolic mechanism used by plants to create seed oil.



The results, described Wednesday in the British journal Nature, address a longstanding question in plant biology – why do oilseed plants rely on a seemingly inefficient metabolic process to produce such prodigious amount of energy-rich oil? The answer, according to the MSU team, is that plant seeds are more efficient than anyone thought. "Seeds achieve this high efficiency by using long-known biochemical reactions that are combined in an unconventional way, which had not been expected by biochemists," said Jörg Schwender, MSU plant biology professor and lead author of the study.

The researchers studied canola (or rapeseed), an annual crop in the mustard family that is widely cultivated throughout the upper Midwest, Canada, Europe and Asia. The oil extracted from the seeds of this plant is used to make everything from margarine to industrial lubricants. Seeds store large oil reserves to use as energy to germinate and grow. In canola, for example, oil can comprise half of the seed’s weight. The rise of modern biochemistry over the last few decades has increased interest in making quantitative descriptions of plants and animals’ biochemical reactions.


When it came to canola, the biochemical balance sheet just didn’t add up. As far as researchers could tell, the seeds were relying on a creaky and inefficient pathway to produce their sought-after oil. All plants employ carbon from carbon dioxide to make organic biomass compounds such as sugars, oils and proteins in stems, leaves and flowers.

To harvest carbon from the air, plants go to lots of trouble to convert carbon dioxide into simple sugars. When canola subsequently transformed these sugars into oils, the plants appeared to cough up lots of the carbon dioxide back into the atmosphere. The chemical reaction appeared to follow the same backwards logic as a person who toils all day on the job to earn $100, only to buy a $5 sandwich and give the remainder of his paycheck back to his employer. In its experiment, the MSU team tagged carbon atoms and tracked how they were processed by developing canola seeds.

During the conversion of sugars to oils, researchers expected to see the tagged carbon go through a step-by-step series of chemical reactions known as glycolysis, used by all plants and animals to turn sugar into energy and cellular building blocks. This energy, in turn, is used to link the carbon building blocks into molecules of oil. Instead, the scientists observed an enzyme called Rubisco providing a more efficient pathway to convert sugar to carbon chains for oil. And the pathway involved lots less coughing up of carbon dioxide.

Scientists have long known that in the process of photosynthesis, Rubisco is the key enzyme that captures atmospheric carbon dioxide for conversion into sugars. However, the MSU team was surprised to see Rubisco – the enzyme’s shorthand stands for ribulose bisphosphate carboxylase/oxygenase – also acting as a key agent producing oil in the seed. In fact, in terms of metabolic heavy-lifting, Rubisco appeared to be much more efficient than glycolysis. The newly uncovered Rubisco bypass pathway produced 20 percent more of the carbon-chain building blocks to make oil while losing 40 percent less carbon dioxide than is lost during glycolysis.

The results cast new light on the seemingly well-understood protein Rubisco, which accounts for 50 percent of a plant’s total protein content and is likely the mostly abundant protein on Earth. Through its role in the snatching carbon atoms from atmospheric carbon dioxide, Rubisco has been recognized as the main chemical gateway for carbon to enter the biosphere. The new findings suggest that Rubisco also gives plants a way to greatly reduce losses back to the atmosphere while they’re synthesizing oil. "Understanding the pathways plants use to make oil will help us to develop new crop varieties with greater oil content," said co-author John Ohlrogge, MSU distinguished professor of plant biology and Michigan Agricultural Experiment Station scientist. "And this becomes especially important as the world depletes its supplies of petroleum."

Jörg Schwender | EurekAlert!
Further information:
http://www.msu.edu

More articles from Life Sciences:

nachricht Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute

nachricht Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>