Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Erratic proteins: new insights into a transport mechanism

30.09.2013
The outer membrane of bacteria contains many proteins that form tiny pores. They are important for absorbing nutrients and transmitting signals into the cell.

The research group of Sebastian Hiller, Professor of Structural Biology at the Biozentrum, University of Basel, has now shown for the first time at atomic resolution, that these pore proteins are transported in an unstructured, constantly changing state to the outer bacterial membrane. This landmark study was recently published in the scientific journal “Nature Structural and Molecular Biology”.

The cell membrane of a bacterium is a natural barrier to the environment and at the same time, their door to the world. Gram-negative bacteria surround themselves with two membrane layers. They communicate with the environment through proteins that form tiny pores in the outer cell membrane. How these membrane proteins reach their target destination in the bacterium Escherichia coli could now be observed for the first time at the atomic level by Professor Sebastian Hiller, from the Biozentrum at the University of Basel.

Molecular “ferry” ensures safe protein transport
New proteins are produced in the protein factories inside the cell. Proteins destined for the outer membrane require a molecular “ferry” to remain intact as they pass the aqueous layer between the two membranes. The protein Skp is such a ferry, transporting the not yet folded proteins across the periplasmic space. At the outer membrane, they fold into their three-dimensional structure and incorporate into the outer membrane.

The current study by Hiller provides an exceptional and deep insight into this transport mechanism. The membrane protein is loosely embedded in the solid structure of Skp during transport and does not adopt on a defined spatial structure itself. “Amazingly, the unfolded protein changes its state constantly – faster than thousand times per second and more than ten million times during the crossing,” explained Hiller. “Only through employing modern nuclear magnetic resonance spectroscopy, it has become possible to detect this dynamic behavior within Skp.” Transporting the membrane protein in such a changing state does not require energy and allows for its rapid release at the destination.

Dynamic transport as a general principle
Although the structure of Skp has been known for a long time, the current study shows that the dynamics of the Skp-membrane protein complex is important for the formation of the outer membrane proteins. With the atomic resolution measurements, Hiller and his team were also able to uncover a general principle how proteins can be transported without requiring energy. In the future, the team of scientists wants to investigate further proteins that are involved in the transport and folding process.
Original Source
Björn M Burmann, Congwei Wang & Sebastian Hiller (2013)
Conformation and dynamics of the periplasmic membrane-protein–chaperone complexes OmpX–Skp and tOmpA–Skp

Nature Structural & Molecular Biology, Published online 29 September 2013 | doi: 10.1038/nsmb.2677

Reto Caluori | idw
Further information:
http://www.unibas.ch
http://www.unibas.ch/index.cfm?uuid=96855398D62121F8339989EA09D23513&type=search&show_long=1&o_lang_id=2

More articles from Life Sciences:

nachricht Cancer diagnosis: no more needles?
25.05.2018 | Christian-Albrechts-Universität zu Kiel

nachricht Less is more? Gene switch for healthy aging found
25.05.2018 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>