Featured Research

from universities, journals, and other organizations

Bacteria Fight Back: Biofilms Use Chemical Weapons To Neutralize Or Kill Attacking Amoebae

Date:
July 25, 2008
Source:
Helmholtz Association of German Research Centres
Summary:
Biofilms develop on any surface that bacteria can attach themselves to. The dilemma we face is that neither disinfectants and antibiotics, nor phagocytes and our immune system can destroy these biofilms. Scientists have now identified one of the fundamental mechanisms used by the bacteria in biofilms to protect themselves against the attacking phagocytes.

Biofilm in green, amoebae in red.
Credit: Helmholtz-Zentrum für Infektionsforschung

Bacteria rarely come as loners; more often they grow in crowds and squat on surfaces where they form a community together. These so-called biofilms develop on any surface that bacteria can attach themselves to. The dilemma we face is that neither disinfectants and antibiotics, nor phagocytes and our immune system can destroy these biofilms.

This is a particular problem in hospitals if these bacteria form a community on a catheter or implant where they could potentially cause a serious infection. Scientists at the Helmholtz Centre for Infection Research in Braunschweig have now identified one of the fundamental mechanisms used by the bacteria in biofilms to protect themselves against the attacking phagocytes.

The scientists are now publishing their findings in the PLoS One, together with colleagues from Australia, Great Britain and the USA -- the discovery being that biofilm bacteria use chemical weapons to defend themselves.

Until now, scientists have been unable to understand the root of the biofilm problem -- the inability of phagocytes to destroy these biofilms. Dr. Carsten Matz decided to investigate this problem. As a model for his investigation, this Braunschweig-based researcher decided to look at marine bacteria. They face constant threats in their habitat from environmental phagocytes, the amoebae, which behave in a similar way in the sea as the immune cells in our body: they seek out and feed on the bacteria. So long as bacteria are swimming freely and separately in the water, they are easy pickings for these predators. However, if they become attached to a surface and socialize with other bacteria, the amoebae can no longer successfully attack them. "The surprising thing was that the amoebae attacking the biofilms were de-activated or even killed. The bacteria are clearly not just building a fortress, they are also fighting back," says Carsten Matz.

The bacteria utilise chemical weapons to achieve this. A widespread and highly effective molecule used by marine bacteria is the pigment violacein. Once the defence system is ready, the biofilm shimmers a soft purple colour. If the attackers consume just a single cell of the biofilm -- and the pigment they contain -- this paralyses the attackers momentarily and the violacein triggers a suicide mechanism in the amoebae.

"I feel that these results could offer a change of perspective," says Carsten Matz. "Biofilms may no longer be seen just as a problem; they may also be a source of new bioactive agents. When organized in biofilms, bacteria produce highly effective substances which individual bacteria alone cannot produce." And the scientists hope to use these molecules to combat a specific group of pathogens: Human parasites that cause devastating infections such as sleeping illness and malaria. Amoeba are ancient relatives of these pathogens and thus biofilm-derived weapons may provide an excellent basis for the design of new parasiticidal drugs.


Story Source:

The above story is based on materials provided by Helmholtz Association of German Research Centres. Note: Materials may be edited for content and length.


Cite This Page:

Helmholtz Association of German Research Centres. "Bacteria Fight Back: Biofilms Use Chemical Weapons To Neutralize Or Kill Attacking Amoebae." ScienceDaily. ScienceDaily, 25 July 2008. <www.sciencedaily.com/releases/2008/07/080723094848.htm>.
Helmholtz Association of German Research Centres. (2008, July 25). Bacteria Fight Back: Biofilms Use Chemical Weapons To Neutralize Or Kill Attacking Amoebae. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2008/07/080723094848.htm
Helmholtz Association of German Research Centres. "Bacteria Fight Back: Biofilms Use Chemical Weapons To Neutralize Or Kill Attacking Amoebae." ScienceDaily. www.sciencedaily.com/releases/2008/07/080723094848.htm (accessed July 25, 2014).

Share This




More Plants & Animals News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

How to Make Single Serving Smoothies: Howdini Hacks

How to Make Single Serving Smoothies: Howdini Hacks

Howdini (July 24, 2014) — Smoothies are a great way to get in lots of healthy ingredients, plus they taste great! Howdini has a trick for making the perfect single-size smoothie that will save you time on cleanup too! All you need is a blender and a mason jar. Video provided by Howdini
Powered by NewsLook.com
Boy Attacked by Shark in Florida

Boy Attacked by Shark in Florida

Reuters - US Online Video (July 24, 2014) — An 8-year-old boy is bitten in the leg by a shark while vacationing at a Florida beach. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Goma Cheese Brings Whiff of New Hope to DRC

Goma Cheese Brings Whiff of New Hope to DRC

Reuters - Business Video Online (July 24, 2014) — The eastern region of the Democratic Republic of Congo, mainly known for conflict and instability, is an unlikely place for the production of fine cheese. But a farm in the village of Masisi, in North Kivu is slowly transforming perceptions of the area. Known simply as Goma cheese, the Congolese version of Dutch gouda has gained popularity through out the region. Ciara Sutton reports. Video provided by Reuters
Powered by NewsLook.com
Tyrannosaur Pack-Hunting Theory Aided By New Footprints

Tyrannosaur Pack-Hunting Theory Aided By New Footprints

Newsy (July 24, 2014) — A new study claims a set of prehistoric T-Rex footprints supports the theory that the giant predators hunted in packs instead of alone. 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