Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A new role for vitamin B6 in plants

09.02.2016

Vitamin B6, which exists in different natural forms called vitamers, is essential for all living organisms, as it participates in numerous aspects of cells’ everyday life. Researchers from the University of Geneva, Switzerland, and collaborators have discovered an unexpected role for this micronutrient, in relation to nitrogen metabolism. Described in the journal The Plant Cell, the results indicate that one of the vitamers informs the plant of its content in ammonium, a basic nitrogen compound needed e.g. for the biosynthesis of proteins. In the future, vitamin B6 could be used to ascertain the nitrogen status of plants and eventually prevent the overuse of nitrogen-containing fertilizers.

Essential for all living organisms, Vitamin B6, which exists in six different forms called vitamers, is produced by plants, bacteria, and fungi, but not by animals. However, it is not known why organisms have several vitamers and if their balance (homeostasis) is of importance. In plants, the various vitamers can be produced via different specific pathways.


Young Arabidopsis plants: wild (top) and with PDX3 deficiency (bottom).

Teresa Fitzpatrick, UNIGE

“We study these pathways to determine their contribution to cellular vitamin B6 homeostasis and to growth and development”, explains Teresa Fitzpatrick, professor at the Department of Botany and Plant Biology of the Faculty of Sciences of UNIGE, who led the study.

In collaboration with the Max Planck Institute of Molecular Plant Physiology and the University of Düsseldorf (Germany), the researchers examined a version of the model plant Arabidopsis thaliana (thale cress), which is defective in the PDX3 enzyme. Surprisingly, these plants displayed strongly impaired growth and development.

“PDX3-defective plants cannot transform a vitamer called PMP, therefore the latter accumulates within the cell. While we hypothesized that the observed anomalies may be due to the high levels of PMP, we had no idea of the underlying mechanism and questioned its precise contribution”, says Maite Colinas, member of the Geneva team and first author of the study.

The answer came from an unexpected discovery: the observed growth anomalies of the mutants were completely abrogated when the plants were supplemented with ammonium. “In most natural soils the predominant nitrogen source for plants is nitrate, as they usually contain little ammonium. Plants must therefore import the former and convert it to ammonium, which can then be used for the biosynthesis of nitrogenous compounds including proteins to promote plant growth”, notes Teresa Fitzpatrick.

It turns out from the scientists’ investigation that the high levels of PMP in the PDX3-defective plants interfere with the conversion of nitrate into ammonium, resulting in an ammonium deficiency that is responsible for the impaired growth and development.

As the connection between nitrogen and vitamin B6 metabolism had never been made, the biologists further examined the potential interactions between these two processes in natural wild-type plants. They indeed observed a considerable accumulation of the PMP vitamer in plants supplemented with ammonium. “When the plant contains enough ammonium for its needs, further production from nitrate is prevented, thus limiting energy waste and potential toxicity that can happen if too much is made. The level of PMP probably informs the plant about its ammonium state”, reports Maite Colinas.

While scientists knew that plants acquired nitrogen from nitrate or ammonium to meet their needs, they were uncertain of how the plant monitored the level or proportion of these compounds. Here, the researchers have found an unanticipated player in this process: the vitamer PMP. The group is currently investigating whether PMP regulates nitrogen metabolism directly or indirectly, via the action of other compounds. In the future, vitamin B6 could be used to ascertain the nitrogen status of plants and eventually prevent the overuse of nitrogen-containing fertilizers that are currently having detrimental effects on the environment.

Weitere Informationen:

http://www.unige.ch/

Dipl. Ing. agr. Ursula Ross-Stitt | Max-Planck-Institut für Molekulare Pflanzenphysiologie
Further information:
http://www.mpimp-golm.mpg.de

More articles from Life Sciences:

nachricht 'Lipid asymmetry' plays key role in activating immune cells
20.02.2018 | Biophysical Society

nachricht New printing technique uses cells and molecules to recreate biological structures
20.02.2018 | Queen Mary University of London

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

'Lipid asymmetry' plays key role in activating immune cells

20.02.2018 | Life Sciences

MRI technique differentiates benign breast lesions from malignancies

20.02.2018 | Medical Engineering

Major discovery in controlling quantum states of single atoms

20.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>