Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UC Santa Barbara researchers uncover new pathways in bacterial intercellular competition

09.04.2013
There's an epic battle taking place that's not on the national radar: intercellular competition. While it's not an Olympic event, new research from UC Santa Barbara demonstrates that this microscopic rivalry can be just as fierce as humans going for the gold.

Christopher Hayes, UCSB associate professor of molecular, cellular and developmental biology, along with postdoctoral fellow Sanna Koskiniemi, graduate student James Lamoureux, and others, examined the role certain proteins, called rearrangement hotspots (Rhs), play in intercellular competition in bacteria. The findings appear today in the Proceedings of the National Academy of Sciences.

Rhs proteins and related YD-peptide repeat proteins are present in a wide range of bacterial species and other organisms, including human beings, where they help establish communications between neurons in the brain when the visual system is developing. Hayes and his team found that Rhs proteins enable Dickeya dadantii 3937, a phytopathogenic bacterium causing soft rot diseases on many crops, to compete with members of its own kind through touch-dependent killing.

While Rhs have been recognized for more 30 years, their function has been enigmatic. This new research sheds light on the mystery. Rhs proteins possess a central repeat region, characteristically the YD-repeat proteins also found in humans, as well as variable C-terminal sequences, which have toxin activity. C-terminal regions are highly variable between bacterial strains even in the same species, indicating that a wide variety of weapons are deployed.

"Bacteria almost always have a different Rhs toxins," explained Hayes. "No one really knows why, but perhaps the toxins are rapidly evolving, driven by intercellular competition. In essence, these cells are fighting it out with each other. It's like an arms race to see who has the best toxins."

Cellular competition is analogous to that between humans and reflects a scarcity of resources. Like people, bacteria need a place to live and food to eat. "We think these systems are important for bacterial cells to establish a home and defend it against competitors," said Hayes. "In fact, bacteria have many systems for competition. And as we uncover more mechanisms for intercellular competition, we realize this is a fundamental aspect of bacterial biology."

These findings demonstrate that Rhs systems in diverse bacterial species are toxin delivery machines. "We have been able to show that gram-negative (Dickeya dadantii) as well as gram-positive (Bacillus subtilis) bacteria use Rhs proteins to inhibit the growth of neighboring bacteria in a manner that requires cell-to-cell contact," said Koskiniemi, the paper's lead author.

The toxic part of Rhs at the tip (the C-terminal region) is delivered into target cells after cell-to-cell contact. Some toxic tips destroy DNA and others destroy transfer RNA, which is essential for protein synthesis. These toxin activities help the bacteria expressing them to outcompete other members of the same species not carrying an antidote.

This work may help scientists design Rhs-based bacterial probiotics that kill specific pathogens but leave most normal flora unharmed. The research was supported by grants from the National Science Foundation and National Institutes of Health and by fellowships from the Carl Tryggers and Wenner-Gren Foundations.

Julie Cohen | EurekAlert!
Further information:
http://www.ucsb.edu/

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 >>>