Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Helpers for energy acquisition from plants

06.09.2016

Research into plant cells is far from complete. Scientists under the biochemist Professor Peter Dörmann at Universität Bonn have now succeeded in describing the function of chloroplasts in more detail. These are plant and algal cell structures that are responsible for photosynthesis. The results have now been published in the scientific journal "Proceedings of the National Academy of Sciences of the USA" (PNAS).

The study makes reference to the endosymbiotic theory, which was put forward back in 1883 by the Bonn university scholar Andreas Franz Wilhelm Schimper and has long been viewed as proven.


Investigated the chloroplasts of Arabidopsis thaliana: Barbara Kalisch and Prof. Peter Dörmann of the Institute of Molecular Physiology and Biotechnology of Plants at Universität Bonn.

© Photo: Barbara Frommann / University of Bonn

According to the theory, at least a billion years ago, a photosynthetic bacterium must have penetrated a plant host cell, where it developed into a chloroplast. Without this so-called "endosymbiosis", photosynthesis, which is the process by which light energy converts carbon dioxide and water into sugar and oxygen, would not be possible in plants.

This former bacterium inside the host cell is surrounded by two membranes. The predominant components of these membranes are the so-called galactolipids. These two envelope membranes were the focus of attention of the scientists during their years of investigation.

"The question that our research sought to answer was exactly what each membrane is responsible for", explains Professor Peter Dörmann, Director of the Institute of Molecular Physiology and Biotechnology of Plants at Universität Bonn.

Scientists experiment with plant mutants

For this purpose, the scientists experimented with mutants of the often-used research plant thale cress (Arabidopsis thaliana). They modified the mutant plant by adding various genetically manipulated variants of a protein of the galactolipid production system, which is located on the outer membrane of the chloroplast. The most important finding: This protein is essential for the embedding of the former bacterium in the cell.

"Without the protein, the chloroplast cannot survive. Without the chloroplast, the plant cannot survive", says Barbara Kalisch, doctoral researcher at Universität Bonn, who was one of the lead authors for the now published article.

"Lipids cannot simply move through water"

In addition to the production of the galactolipids, the protein is also involved in the transfer of galactolipids from the outer to the inner of the two envelope membranes. In their experiments, the researchers also placed the protein artificially on the inner membrane. Lipid production worked there, too; the plant remained able to survive. When the protein is on the inner envelope membrane, no further transport is necessary. Why the location in nature is on the outside and not the inside, has not yet been clarified.

The experiments also indicate that the protein is the reason that there can be any lipid exchange at all between the two envelope membranes of the chloroplasts. That is important, so that the chloroplast, and with it the plant, can grow. The space between the two envelope membranes is filled with water, but "lipids cannot simply move through water", explains Prof. Peter Dörmann of Universität Bonn. However, other factors can affect this lipid exchange. "Our investigations to date certainly do not represent the end of our research", says Dörmann.

Publication: Amélie A. Kelly, Barbara Kalisch, Georg Hölzl, Sandra Schulze, Juliane Thiele, Michael Melzer, Rebecca L. Roston, Christoph Benning, and Peter Dörmann: Synthesis and transfer of galactolipids in the chloroplast envelope membranes of Arabidopsis thaliana, "Proceedings of the National Academy of Sciences of the USA", DOI: 10.1073/pnas.1609184113

Contact for the media:

Prof. Peter Dörmann
Institute of Molecular Physiology and
Biotechnology of Plants
Universität Bonn
Tel.: +49-228 73-2830
E-Mail: doermann@uni-bonn.de

Johannes Seiler | idw - Informationsdienst Wissenschaft
Further information:
http://www.uni-bonn.de/

More articles from Life Sciences:

nachricht Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden

nachricht The pyrenoid is a carbon-fixing liquid droplet
22.09.2017 | Max-Planck-Institut für Biochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>