Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

How Plants isolate themselves against Bacteria

29.05.2015

When plants notice harmful bacteria, they respond very quickly: They close the pores on their leaves which serve as loophole for the pathogens. A Würzburg research team has analysed this process.

Plants are continuously besieged by viruses, fungi and bacteria. This is the reason why immune responses have developed in the course of evolution with which they defend themselves against many pathogenic microorganisms. An international research team has now analysed an immune response which complicates the penetration of bacteria into the leaves.


Bacteria use open pores in order to get into the inside of the leave (A). If the plant notices the bacterial flagellin, the OST1 enzyme activates the ion channels SLAC1 and SLAH3, and the pores close

(Graphics: Rob Roelfsema)

There are many very small pores in the leaves that can open wide or close completely. Through these holes in their skin, plants regulate the vital exchange of air and water with the environment. However, the pores also harbour a risk: They are welcome loopholes for pathogenic bacteria through which they can enter into the plant.

What happens in the event of a bacterial infection on the leave pores, the stomata, has so far been virtually unknown. An international research team has just published new findings about this issue in the “New Phytologist” journal. The plant scientists Rainer Hedrich and Rob Roelfsema from the University of Würzburg form the core of the team. The molecular mechanisms for controlling the stomata have been their focus for many years in their study groups.

Injecting the bacterial protein flagellin into leaves

How do stomata respond to an infestation of bacteria? This is what Aysin Guzel Deger, currently a guest PhD student at the University of Würzburg, from the University of Mersin (Turkey), wanted to find out.

For this, she injected the bacterial protein flagellin into the leaves of the model plant Arabidopsis (Arabidopsis thaliana). This protein occurs in many bacteria. The plants obviously consider it dangerous and as a result respond very quickly: About 15 minutes after the injection they start to close their stomata. This is how they block the entry path of the bacteria.

The flagellin develops its effect on the guard cells which limit the stomata of the plant: Each leaf pore is lined by two cells and they ensure that the pore size can be changed. In cooperation with a team from Estonia, the Würzburg team found out exactly where the flagellin has an effect on the guard cells: “Through the OST1 enzyme it activates the ion channels SLAC1 and SLAH3. As a result the guard cells go limp and the pores close”, explains Roelfsema.

Flagellin activates the dry stress signal path

Interestingly, the enzyme and the two ion channels are also contributors when plants close their pores in the event of dryness. This way they reduce the loss of water to the environment, as Hedrich’s team already found out quite a while ago.

Dryness and bacterial pathogens therefore activate the same signal path in plants: In plant cultivation, this new finding could be used to catch two birds with one stone: “Cultivated plants with improved OST1 enzymes may at the same time be more resistant against dryness and against bacteria, says professor Hedrich. For farming, this is an exciting perspective, because dryness and pests are among the main factors that contribute to worldwide crop losses.

“Guard cell SLAC1-type anion channels mediate flagellin-induced stomatal closure”, Aysin Guzel Deger, Sönke Scherzer, Maris Nuhkat, Justyna Kedzierska, Hannes Kollist, Mikael Brosché, Serpil Unyayar, Marie Boudsocq, Rainer Hedrich, and M. Rob G. Roelfsema. New Phytologist, published online on 30 April 2015, DOI: 10.1111/nph.13435

Contact

Prof. Dr. Rainer Hedrich, Department of Botany I (Molecular Plant Physiology and Biophysics) of the University of Würzburg, T (0931) 31-86100, hedrich@botanik.uni-wuerzburg.de

PD Dr. Rob Roelfsema, Department of Botany I (Molecular Plant Physiology and Biophysics) of the University of Würzburg, T (0931) 31-86121, roelfsema@botanik.uni-wuerzburg.de

Robert Emmerich | Julius-Maximilians-Universität Würzburg
Further information:
http://www.uni-wuerzburg.de

More articles from Life Sciences:

nachricht Cnidarians remotely control bacteria
21.09.2017 | Christian-Albrechts-Universität zu Kiel

nachricht Immune cells may heal bleeding brain after strokes
21.09.2017 | NIH/National Institute of Neurological Disorders and Stroke

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

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...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

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

Comet or asteroid? Hubble discovers that a unique object is a binary

21.09.2017 | Physics and Astronomy

Cnidarians remotely control bacteria

21.09.2017 | Life Sciences

Monitoring the heart's mitochondria to predict cardiac arrest?

21.09.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>