Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Montana State researcher discovers that bile sends mixed signals to E. coli

01.04.2010
Bile secretions in the small intestine send signals to disease-causing gut bacteria allowing them to change their behavior to maximize their chances of surviving, Montana State University research associate Steve Hamner told the Society for General Microbiology during its spring meeting in Edinburgh, Scotland.

An SGM press release said the findings could allow us to better protect food from contamination by these harmful bacteria, as well as understand how they manage to cause disease.

Bile is secreted into the small intestine and exerts an antibacterial effect by disrupting bacterial membranes and damaging bacterial DNA, the release said. While bile is a human defense mechanism, Hamner and his colleagues at MSU and the University of New England found that some bacteria such as Escherichia coli O157:H7 -- an important food-borne pathogen known as E. coli -- have evolved to use the signal to their advantage. These bacteria use the presence of bile as a signal to tell them that they are in the intestine which allows them to adapt and prepare to cause disease.

Hamner's team found that bile causes the bacteria to switch on genes needed to increase iron uptake.

"This is useful in iron-scarce environments -- such as the small intestine -- as iron is an essential nutrient for bacterial growth. By increasing its chances of absorbing iron, the bacterium is maximizing its survival chances," Hamner explained.

E. coli O157:H7 primarily infects the large intestine, and this study provides one explanation why this is the case.

"We found that bile causes the bacteria to turn off genes that promote tight attachment to host cells. Bile may effectively prevent these bacteria from latching onto the epithelial cells that line the small intestine," Hamner suggested.

As bacteria move further down the digestive tract towards the large intestine, the concentration of bile decreases.

"The reduced concentration of bile in the large intestine may then be a signal for the bacteria to switch on their ability to attach to epithelial cells and to prepare to secrete toxins," Hamner said.

Studying the conditions that make these bacteria more likely to attach themselves to cells could help reduce outbreaks of food poisoning.

"By learning how the bacteria attach to food surfaces such as spinach leaves or to host tissues such as the lining of the intestine, we hope to better be able to protect food sources from contamination by these bacteria. Studying how these bacteria interact with hosts such as humans or cows could teach us how to interfere with the way that these bacteria cause disease," Hamner said.

The Society for General Microbiology is the largest microbiology society in Europe, and has over 5,500 members worldwide. Its spring meeting was held March 29 through April 1.

Evelyn Boswell | EurekAlert!
Further information:
http://www.montana.edu

More articles from Life Sciences:

nachricht Climate Impact Research in Hannover: Small Plants against Large Waves
17.08.2018 | Leibniz Universität Hannover

nachricht First transcription atlas of all wheat genes expands prospects for research and cultivation
17.08.2018 | Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Quantum material is promising 'ion conductor' for research, new technologies

17.08.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>