Featured Research

from universities, journals, and other organizations

Fighting bacteria’s strength in numbers

Date:
May 17, 2012
Source:
University of Nottingham
Summary:
Scientists have opened the way for more accurate research into new ways to fight dangerous bacterial infections by proving a long-held theory about how bacteria communicate with each other.

Scientists at The University of Nottingham have opened the way for more accurate research into new ways to fight dangerous bacterial infections by proving a long-held theory about how bacteria communicate with each other.

Researchers in the University's School of Molecular Medical Sciences have shown for the first time that the effectiveness of the bacteria's communication method, a process called 'quorum sensing', directly depends on the density of the bacterial population. This work will help inform wider research into how to stop bacteria talking to each other with the aim of switching off their toxin production.

As some pathogenic organisms are increasingly resistant to traditional antibiotics, medical researchers around the world, including scientists at The University of Nottingham, are trying to find other ways of fighting infection. This new work involves using 'quorum quenching' compounds which interfere with bacterial signalling and disrupt their social lives.

Quorum sensing (QS) is the process by which bacteria communicate and co-operate using signal molecules which control, among other things, the production of toxins. QS is therefore an important factor in a number of bacterial species that cause serious infection in humans including Pseudomonas aeruginosa, a leading cause of death among cystic fibrosis sufferers, and MRSA which is a huge clinical problem in hospitals.

Leading the research at Nottingham, Dr Stephen Diggle said: "The fundamental assumption used to explain QS, is that the production of QS-controlled factors is not beneficial until a sufficient density of cells (a quorum) is present, and that the purpose of QS is to stimulate social behaviours only when high enough bacterial population densities are reached. For a pathogen this makes sense. Why produce toxins when there are not many cells around? Why not wait until a large number are present and coordinate production of toxin on mass which helps to overwhelm a host? This density assumption, upon which the entire QS field is based, has never been experimentally tested until now."

This ground-breaking research has just been published in the leading international journal, Proceedings of the National Academy of Sciences. It shows for the first time that cell density is an important factor in regulating QS in the opportunistic pathogen Pseudomonas aeruginosa. Using a combination of special growth media and molecular techniques, the work has shown that QS signalling occurs in low populations of cells but that there is no benefit to the bacteria of doing so. QS is therefore most useful to the bacteria at high cell densities.

A challenge for researchers in the future is to study this in more natural environments such as infections. Bacteria such as P. aeruginosa use QS to control toxin production and this new research helps to explain how certain infections can suddenly turn life threatening due to massive toxin release. This suggests that carefully controlling bacterial population density within infections could be helpful in avoiding toxin-related damage.


Story Source:

The above story is based on materials provided by University of Nottingham. Note: Materials may be edited for content and length.


Journal Reference:

  1. S. E. Darch, S. A. West, K. Winzer, S. P. Diggle. Density-dependent fitness benefits in quorum-sensing bacterial populations. Proceedings of the National Academy of Sciences, 2012; DOI: 10.1073/pnas.1118131109

Cite This Page:

University of Nottingham. "Fighting bacteria’s strength in numbers." ScienceDaily. ScienceDaily, 17 May 2012. <www.sciencedaily.com/releases/2012/05/120517115341.htm>.
University of Nottingham. (2012, May 17). Fighting bacteria’s strength in numbers. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2012/05/120517115341.htm
University of Nottingham. "Fighting bacteria’s strength in numbers." ScienceDaily. www.sciencedaily.com/releases/2012/05/120517115341.htm (accessed July 28, 2014).

Share This




More Plants & Animals News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
Powered by NewsLook.com
Trees Could Save More Than 850 Lives Each Year

Trees Could Save More Than 850 Lives Each Year

Newsy (July 27, 2014) A national study conducted by the USDA Forest Service found that trees collectively save more than 850 lives on an annual basis. Video provided by Newsy
Powered by NewsLook.com
What's To Blame For Worst Ebola Outbreak In History?

What's To Blame For Worst Ebola Outbreak In History?

Newsy (July 27, 2014) A U.S. doctor has tested positive for the deadly Ebola virus, as the worst-ever outbreak continues to grow. Video provided by Newsy
Powered by NewsLook.com
The New York Times Backs Pot Legalization

The New York Times Backs Pot Legalization

Newsy (July 27, 2014) The New York Times has officially endorsed the legalization of marijuana, but why now, and to what end? 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:
from the past week

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