Featured Research

from universities, journals, and other organizations

Poisonous effect of intestinal bacteria explained: Researchers identify site of action of cytotoxin produced by 'hypervirulent' intestinal flora

Date:
September 26, 2011
Source:
Albert-Ludwigs-Universität Freiburg
Summary:
Researchers have discovered the cell receptor for the toxin CDT of the bacterium Clostridium difficile. These germs often cause an inflammation of the colon in patients who have recently received a treatment with antibiotics.

A research group led by Freiburg pharmacologist Prof. Dr. Klaus Aktories and their American colleagues have discovered the cell receptor for the toxin CDT of the bacterium Clostridium difficile. These germs often cause an inflammation of the colon in patients who have recently received a treatment with antibiotics.

The results of the study were published in the Proceedings of the National Academy of Sciences (PNAS).

Antibiotics damage bacteria of the normal intestinal flora, allowing Clostridium difficile germs to proliferate freely. The germs produce two typical toxins that cause an inflammation in the mucous membrane of the colon and destroy it. The consequences are diarrhea and psudomembranous colitis, an infection that is often lethal in older patients.

Due to the rapid proliferation of Clostridium difficile spores, their resistance to many disinfectants, and the frequent use of antibiotics, infections with Clostridium difficile are a major medical and hygienic problem in hospitals around the world. Particularly alarming is the appearance of so-called hypervirulant strains of Clostridium difficile, which produce more of these typical toxins, are resistant to antibiotics, and also produce a third cytotoxin (CDT) that attacks the cytoskeleton directly.

The Freiburg researchers and their colleagues from the Whitehead Institute, USA, identified the cell receptor of this additional toxin of particularly virulent clostridia. In order to find the receptor, the scientists used a new genetic procedure focusing on cancer cells that only possess one set of chromosomes. These cancer cells are susceptible to the CDT toxin of Clostridium difficile and die off from its poisonous effect. It was already known that this CDT toxin binds to a receptor on the surface of the cells, from where it can penetrate into the cell's interior by way of a complex procedure. However, the receptor itself was previously unknown.

The researchers succeeded in demonstrating that cells that are resistant to the CDT toxin are made susceptible to it by the receptor. The findings will enable scientists to develop new strategies to prevent the toxin from entering target cells.


Story Source:

The above story is based on materials provided by Albert-Ludwigs-Universität Freiburg. Note: Materials may be edited for content and length.


Journal Reference:

  1. P. Papatheodorou, J. E. Carette, G. W. Bell, C. Schwan, G. Guttenberg, T. R. Brummelkamp, K. Aktories. Lipolysis-stimulated lipoprotein receptor (LSR) is the host receptor for the binary toxin Clostridium difficile transferase (CDT). Proceedings of the National Academy of Sciences, 2011; DOI: 10.1073/pnas.1109772108

Cite This Page:

Albert-Ludwigs-Universität Freiburg. "Poisonous effect of intestinal bacteria explained: Researchers identify site of action of cytotoxin produced by 'hypervirulent' intestinal flora." ScienceDaily. ScienceDaily, 26 September 2011. <www.sciencedaily.com/releases/2011/09/110926094749.htm>.
Albert-Ludwigs-Universität Freiburg. (2011, September 26). Poisonous effect of intestinal bacteria explained: Researchers identify site of action of cytotoxin produced by 'hypervirulent' intestinal flora. ScienceDaily. Retrieved April 20, 2014 from www.sciencedaily.com/releases/2011/09/110926094749.htm
Albert-Ludwigs-Universität Freiburg. "Poisonous effect of intestinal bacteria explained: Researchers identify site of action of cytotoxin produced by 'hypervirulent' intestinal flora." ScienceDaily. www.sciencedaily.com/releases/2011/09/110926094749.htm (accessed April 20, 2014).

Share This



More Health & Medicine News

Sunday, April 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Nine-Month-Old Baby Can't Open His Mouth

Nine-Month-Old Baby Can't Open His Mouth

Newsy (Apr. 19, 2014) — Nine-month-old Wyatt Scott was born with a rare disorder called congenital trismus, which prevents him from opening his mouth. Video provided by Newsy
Powered by NewsLook.com
'Holy Grail' Of Weight Loss? New Find Could Be It

'Holy Grail' Of Weight Loss? New Find Could Be It

Newsy (Apr. 18, 2014) — In a potential breakthrough for future obesity treatments, scientists have used MRI scans to pinpoint brown fat in a living adult for the first time. Video provided by Newsy
Powered by NewsLook.com
Little Progress Made In Fighting Food Poisoning, CDC Says

Little Progress Made In Fighting Food Poisoning, CDC Says

Newsy (Apr. 18, 2014) — A new report shows rates of two foodborne infections increased in the U.S. in recent years, while salmonella actually dropped 9 percent. Video provided by Newsy
Powered by NewsLook.com
Scientists Create Stem Cells From Adult Skin Cells

Scientists Create Stem Cells From Adult Skin Cells

Newsy (Apr. 17, 2014) — The breakthrough could mean a cure for some serious diseases and even the possibility of human cloning, but it's all still a way off. 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