Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers at the RUB and from Taiwan discover energy supply for protein secretion

10.05.2012
Out of the cell

Journal of Biological Chemistry: mechanism of bacterial transport system published

In order to interact with the environment, bacteria secrete a whole arsenal of proteins. Researchers have now found how one of the transportation systems used for this purpose – the type VI secretion system – works for the single-celled organism Agrobacterium tumefaciens. They have identified the relevant transport proteins and their energy suppliers.


Export mechanism: To get to the outside, Hcp has to get past two cell membranes. This is only possible if it forms a complex with the two membrane proteins TssM (grey) and TssL (white). The energy for the export is produced by the interaction of TssM with the energy storage molecule ATP. Figure: modified from the Journal of Biological Chemistry

With colleagues at the Academia Sinica in Taiwan, RUB biologist Prof. Dr. Franz Narberhaus describes the findings in the Journal of Biological Chemistry. “The proteins involved also occur in other secretion apparatuses” explains Narberhaus from the Department of Microbial Biology. “Therefore, the results contribute to the general understanding of the system.”

Protein arsenal for many purposes

Bacteria use secreted proteins to make nutrients available, to fend off competitors and to infect human, animal or plant host cells. “Agrobacterium tumefaciens is a fascinating bacterium. It can genetically modify plants and stimulate tumour formation”, says Narberhaus. Five bacterial secretion systems have been known for a long time. The type VI system was only discovered a few years ago. Among other things, it transports the protein Hcp through two membranes into the environment – for what purpose is, as yet, unclear. The question of how the export of Hcp is driven was also unanswered. This is precisely what the German-Taiwanese team has now revealed.

Membrane protein TssM: the driver of the protein export

Narberhaus and his colleagues have shown that two proteins in the cell membrane of the bacteria, called TssL and TssM, are responsible for the export of Hcp. The molecule ATP, a cellular energy store, serves as fuel for the transport process. The membrane protein TssM binds the energy supplier ATP, thereby changing its own structure and splitting the ATP. The energy thus released allows the associated membrane protein TssL to bind its cargo (Hcp) so that a tripartite complex of TssM, TssL and Hcp is formed. Hcp only passes from the bacterial cell into the environment when this complex forms.

Successful cooperation between Bochum und Taiwan

“Large membrane proteins such as TssM are difficult to study biochemically. Our colleagues in Taiwan have done a great job” Prof. Narberhaus explains. “It will now be particularly interesting to explore the biological significance of the system.” The analyses of ATP splitting, also called hydrolysis, were established in Prof. Narberhaus’s laboratory by the doctoral student Lay-Sun Ma during a research visit. “Because of the participation in the Collaborative Research Centre SFB 642 ‘GTP- and ATP-dependent membrane processes’, we are able to offer ideal conditions for working with ATP-dependent proteins” the RUB-biologist explains. This is the second time that the DAAD has funded the cooperation between the laboratories of Franz Narberhaus and Erh-Min Lai. The successful cooperation is also to continue in the future. “It is bound to last for many years”, the Bochum researcher is convinced. The next exchange of doctoral students is planned for autumn.

Bibliographic record

L.-S. Ma, F. Narberhaus, E.-M. Lai (2012): IcmF family protein TssM exhibits ATPase activity and energizes type VI secretion, Journal of Biological Chemistry, doi: 10.1074/jbc.M111.301630

Further information

Prof. Dr. Franz Narberhaus, Department of Microbial Biology, Faculty of Biology and Biotechnology at the Ruhr-Universität, 44780 Bochum, Germany, Tel. +49/234/32-23100

franz.narberhaus@rub.de

Click for more

Microbial biology at the RUB
http://www.ruhr-uni-bochum.de/mikrobiologie/index_en.html
Editor: Dr. Julia Weiler

Dr. Josef König | idw
Further information:
http://www.ruhr-uni-bochum.de/
http://www.ruhr-uni-bochum.de/mikrobiologie/index_en.html

More articles from Life Sciences:

nachricht Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH

nachricht Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>