Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists uncover amyloid-like proteins in bacteria

09.07.2003


Independent research groups have uncovered a new class of proteins, called the chaplins, that function like amyloid fibrils to allow reproductive growth in the bacterium Streptomyces coelicolor. Amyloid proteins are most commonly recognized for their role in Alzheimer’s disease, where they aggregate into insoluble, mesh-like plaques in the brains of Alzheimer’s patients. This finding reveals an unprecedented role for amyloid-like proteins in Gram-positive bacteria.



S. coelicolor is a soil-dwelling bacterium that, along with its relatives, produces the majority of naturally derived antibiotics (e.g., tetracycline and erythromycin), as well as many antitumor, antifungal, and immunosuppressant agents. Unlike most other prokaryotes, S. coelicolor has a complex life cycle, producing two different cell types depending upon environmental conditions: vegetative substrate hyphae that grow in moist soil, and aerial hyphae that grow in air and give rise to reproductive spores.

As published in the July 15th issue of Genes & Development, independent research carried out by Dr. Marie Elliot, Dr. Mark Buttner and colleagues at the John Innes Centre (UK) and Stanford University (USA), and by Dennis Claessen, Dr. Lubbert Dijkhuizen, Dr. Han Wösten and colleagues at the University of Groningen and the University of Utrecht (Netherlands), have identified the chaplin protein family as essential mediators of aerial S. coelicolor growth. The research in the Netherlands was funded by a grant of the National Programme EET (Economy, Ecology and Technology) to find biological alternatives for the environmentally harmful antifouling compounds used today on ships.


Although the two groups used different experimental approaches to identify genes involved in aerial hyphae formation, both reached a common conclusion. Both groups discovered a previously unidentified family of hydrophobic, cell-surface proteins whose eight members (chaplins A-H) are necessary for aerial hyphae formation. In independent experiments, Elliot et al. and Claessen et al. demonstrated that streptomycetes lacking specific chaplin genes were unable to erect aerial hyphae, but that this condition could be restored through the application of exogenous chaplin proteins.

The authors suggest that coating of the aerial hyphae by chaplin proteins may confer hydrophobicity to these structures, allowing them to grow into the air and possibly even preventing back-growth into the moist soil. "The hydrophobic nature of aerial structures could be an ideal property to prevent organisms from fouling in shipping. In our aim to find biological alternatives for antifouling compounds we are currently studying the antifouling properties of these highly surface active proteins," explains Dennis Claessen, of the University of Groningen.

Dr. Dijkhuizen’s group further investigated the role of the chaplin proteins at the soil/air interface, finding that chaplin genes E and H are also expressed in the submerged substrate hyphae. The researchers went on to show that a mixture of chaplin proteins D - H self-assembled into amyloid-like fibrils at the soil/air interface, suggesting that chaplins D-H may help lower the water surface tension to facilitate the breakthrough of aerial structures into air.

The identification of the chaplin proteins in Streptomyces potentially has important implications for its use by the pharmaceutical industry. "Chaplins adopt an amyoid-like structure, and could therefore be used as a model system to find molecules that prevent formation of amyloid fibrils" said Dennis Claessen and Dr. Marie Elliot. Furthermore, this landmark discovery of functional amyloid-like fibrils in Gram-positive bacteria illustrates the diversity of amyloid function across genomes.

Heather Cosel | EurekAlert!

More articles from Life Sciences:

nachricht A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)

nachricht CWRU researchers find a chemical solution to shrink digital data storage
22.06.2017 | Case Western Reserve University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

Im Focus: Optoelectronic Inline Measurement – Accurate to the Nanometer

Germany counts high-precision manufacturing processes among its advantages as a location. It’s not just the aerospace and automotive industries that require almost waste-free, high-precision manufacturing to provide an efficient way of testing the shape and orientation tolerances of products. Since current inline measurement technology not yet provides the required accuracy, the Fraunhofer Institute for Laser Technology ILT is collaborating with four renowned industry partners in the INSPIRE project to develop inline sensors with a new accuracy class. Funded by the German Federal Ministry of Education and Research (BMBF), the project is scheduled to run until the end of 2019.

New Manufacturing Technologies for New Products

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

A new technique isolates neuronal activity during memory consolidation

22.06.2017 | Life Sciences

Plant inspiration could lead to flexible electronics

22.06.2017 | Materials Sciences

A rhodium-based catalyst for making organosilicon using less precious metal

22.06.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>