Featured Research

from universities, journals, and other organizations

Scientists Uncover Amyloid-like Proteins In Bacteria

Date:
July 9, 2003
Source:
Cold Spring Harbor Laboratory
Summary:
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.

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.

Related Articles


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 Wφsten 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.


Story Source:

The above story is based on materials provided by Cold Spring Harbor Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

Cold Spring Harbor Laboratory. "Scientists Uncover Amyloid-like Proteins In Bacteria." ScienceDaily. ScienceDaily, 9 July 2003. <www.sciencedaily.com/releases/2003/07/030709064008.htm>.
Cold Spring Harbor Laboratory. (2003, July 9). Scientists Uncover Amyloid-like Proteins In Bacteria. ScienceDaily. Retrieved December 20, 2014 from www.sciencedaily.com/releases/2003/07/030709064008.htm
Cold Spring Harbor Laboratory. "Scientists Uncover Amyloid-like Proteins In Bacteria." ScienceDaily. www.sciencedaily.com/releases/2003/07/030709064008.htm (accessed December 20, 2014).

Share This


More From ScienceDaily



More Mind & Brain News

Saturday, December 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) — In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Buzz60 (Dec. 19, 2014) — A double-amputee makes history by becoming the first person to wear and operate two prosthetic arms using only his mind. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Prenatal Exposure To Pollution Might Increase Autism Risk

Prenatal Exposure To Pollution Might Increase Autism Risk

Newsy (Dec. 18, 2014) — Harvard researchers found children whose mothers were exposed to high pollution levels in the third trimester were twice as likely to develop autism. Video provided by Newsy
Powered by NewsLook.com
Yoga Could Be As Beneficial For The Heart As Walking, Biking

Yoga Could Be As Beneficial For The Heart As Walking, Biking

Newsy (Dec. 17, 2014) — Yoga can help your weight, blood pressure, cholesterol and heart just as much as biking and walking does, a new study suggests. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins