Featured Research

from universities, journals, and other organizations

How botulism-causing toxin enters bloodstream

Date:
June 19, 2014
Source:
University of California - Irvine
Summary:
The mechanism by which bacterial toxins that cause food-borne botulism are absorbed through the intestinal lining and into the bloodstream has been discovered by researchers. Their study points to new approaches to blocking this poisonous substance. Botulism is a rare and often fatal paralytic illness due to a neurotoxin produced by Clostridium botulinum bacteria, which can appear in rotted, uncooked foods and in soil.

“By identifying this novel process by which the toxin compound manages to open the door from inside, we can better understand how to seek new methods to prevent these deadly toxins from entering the bloodstream,” Rongsheng Jin said.
Credit: Image courtesy of University of California - Irvine

UC Irvine School of Medicine researchers have discovered the mechanism by which bacterial toxins that cause food-borne botulism are absorbed through the intestinal lining and into the bloodstream. Their study, which appears in the June 20 issue of Science, points to new approaches to blocking this poisonous substance.

Related Articles


Botulism is a rare and often fatal paralytic illness due to a neurotoxin produced by Clostridium botulinum bacteria, which can appear in rotted, uncooked foods and in soil. Listed as a Tier 1 agent by the Centers for Disease Control & Prevention, the botulinum toxin is also a potential biological weapon.

Using a crystal structure of a complex protein compound of botulinum neurotoxin, Rongsheng Jin, associate professor of physiology & biophysics at UC Irvine, and collaborators found that these compounds -- called clostridial hemagglutinin (HA) -- bind with epithelial cell proteins in the intestines of patients, which initiates a process that disrupts the close intercellular seals so that the complex toxin molecules can slip through the epithelial barrier.

"Normally, botulinum neurotoxin molecules are too large to break through this tight junction of epithelial cells," Jin said. "By identifying this novel process by which the toxin compound manages to open the door from inside, we can better understand how to seek new methods to prevent these deadly toxins from entering the bloodstream."

In further tests, he and his colleagues designed a mutated version of the botulism compound, based on the novel crystal structure, in which HA would not bind with the epithelial cell protein E-cadherin.

Remarkably, even though this lab-made toxin compound contains the fully active live toxin molecule, it was not orally toxic when tested on mice because the mutated HA cannot break up the intercellular seals and, therefore, the toxin compound cannot be absorbed through the epithelial layer.

Jin said this approach could lead to the identification of small molecules able to stop HA from binding with epithelial cell proteins, thus preventing the toxin invasion.


Story Source:

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


Journal Reference:

  1. K. Lee, X. Zhong, S. Gu, A. M. Kruel, M. B. Dorner, K. Perry, A. Rummel, M. Dong, R. Jin. Molecular basis for disruption of E-cadherin adhesion by botulinum neurotoxin A complex. Science, 2014; 344 (6190): 1405 DOI: 10.1126/science.1253823

Cite This Page:

University of California - Irvine. "How botulism-causing toxin enters bloodstream." ScienceDaily. ScienceDaily, 19 June 2014. <www.sciencedaily.com/releases/2014/06/140619142210.htm>.
University of California - Irvine. (2014, June 19). How botulism-causing toxin enters bloodstream. ScienceDaily. Retrieved February 1, 2015 from www.sciencedaily.com/releases/2014/06/140619142210.htm
University of California - Irvine. "How botulism-causing toxin enters bloodstream." ScienceDaily. www.sciencedaily.com/releases/2014/06/140619142210.htm (accessed February 1, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Sunday, February 1, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Nanoscale Sensor Could Help Wine Producers and Clinical Scientists

Nanoscale Sensor Could Help Wine Producers and Clinical Scientists

Reuters - Innovations Video Online (Jan. 30, 2015) A nanosensor that mimics the oral effects and sensations of drinking wine has been developed by Danish and Portuguese researchers. Jim Drury saw it in operation. Video provided by Reuters
Powered by NewsLook.com
Dog-Loving Astronaut Wins Best Photo of 2015

Dog-Loving Astronaut Wins Best Photo of 2015

Buzz60 (Jan. 30, 2015) Retired astronaut and television host, Leland Melvin, snuck his dogs into the NASA studio so they could be in his official photo. As Mara Montalbano (@maramontalbano) shows us, the secret is out. Video provided by Buzz60
Powered by NewsLook.com
U.S. Wants to Analyze DNA from 1 Million People

U.S. Wants to Analyze DNA from 1 Million People

Reuters - US Online Video (Jan. 30, 2015) The U.S. has proposed analyzing genetic information from more than 1 million American volunteers to learn how genetic variants affect health and disease. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Rarest Cat on Planet Caught Attacking Monkeys on Camera

Rarest Cat on Planet Caught Attacking Monkeys on Camera

Buzz60 (Jan. 30, 2015) An African Golden Cat, the rarest large cat on the planet was recently caught on camera by scientists trying to study monkeys. The cat comes out of nowhere to attack those monkeys. Patrick Jones (@Patrick_E_Jones) has the rest. Video provided by Buzz60
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


Plants & Animals

Earth & Climate

Fossils & Ruins

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