Featured Research

from universities, journals, and other organizations

Stress Signals Link Pre-existing Sickness With Susceptibility To Bacterial Infection

Date:
August 3, 2009
Source:
The Company of Biologists
Summary:
A new study shows that the stress signaling protein, AMPK, facilitates infection by harmful bacteria. AMPK is chronically elevated in some types of diseases, suggesting that this protein may cause patients with these diseases to be more susceptible to noxious infection.

Mitochondrial diseases disrupt the power generating machinery within cells and increase a person's susceptibility to bacterial infection, particularly in the lungs or respiratory tract. A new study published in Disease Models & Mechanisms, shows that infection with the pneumonia causing bacteria Legionella, is facilitated by an increased amount of a signaling protein that is associated with mitochondrial disease.

Related Articles


Patients with mitochondrial disease exhibit a wide range of symptoms including diabetes, blindness, deafness, stroke-like episodes, epilepsy, ataxia, muscle weakness and kidney disease. The metabolic abnormalities that cause these effects also induce a stress signal intended to help the body overcome its energy deficit. The stress-signal induces the production of more mitochondria, the energy generating 'powerplants' of the body, in the hopes that more mitochondria will result in a better power supply. Researchers now show that the stress-signal associated with mitochondrial disease facilitates the growth and reproduction of the lung-infecting bacteria, Legionella.

Cells with mitochondrial disease increase their production of a signaling protein called AMP-activated protein kinase (AMPK), to promote the generation of more energy producing mitochondria. Infectious bacteria, like Legionella, target the mitochondria and might use them to supplement their own needs and survival requirements. By manipulating AMPK levels, scientists were able to directly influence the ability of bacteria to replicate inside of the single-celled organism, Dictyostelium.

Striking similarities that exist between simple organisms like Dictyostelium and humans allow scientists to use them to understand human disease. Dictyostelium is a free-living amoeba whose rapid movements make it useful to study motility and energy regulation, and in this case, the association between energy regulation and susceptibility to infection. Like humans, Dictyostelium can be infected by Legionella and quickly responds by producing a host of metabolism-associated proteins. Another similarity between humans and Dictyostelium is that both use AMPK as an internal sensor to coordinate energy synthesis with energy needs. However, unlike humans, researchers can infect Dictyostelium with germs like Legionella in a controlled environment and determine the influence of various parameters on the course of infection.


Story Source:

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


Journal Reference:

  1. Lisa Francione, Paige K. Smith, Sandra L. Accari, Paul B. Bokko, Paul Fisher, Salvatore Bozzaro, Phillip E Taylor and Peter L. Beech. Legionella pneumophila multiplication is enhanced by chronic AMPK signalling in mitochondrially diseased cells. Disease Models & Mechanisms, September/October 2009

Cite This Page:

The Company of Biologists. "Stress Signals Link Pre-existing Sickness With Susceptibility To Bacterial Infection." ScienceDaily. ScienceDaily, 3 August 2009. <www.sciencedaily.com/releases/2009/07/090728083247.htm>.
The Company of Biologists. (2009, August 3). Stress Signals Link Pre-existing Sickness With Susceptibility To Bacterial Infection. ScienceDaily. Retrieved March 29, 2015 from www.sciencedaily.com/releases/2009/07/090728083247.htm
The Company of Biologists. "Stress Signals Link Pre-existing Sickness With Susceptibility To Bacterial Infection." ScienceDaily. www.sciencedaily.com/releases/2009/07/090728083247.htm (accessed March 29, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Sunday, March 29, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

S. Leone in New Anti-Ebola Lockdown

S. Leone in New Anti-Ebola Lockdown

AFP (Mar. 28, 2015) — Sierra Leone imposed a three-day nationwide lockdown Friday for the second time in six months in a bid to prevent a resurgence of the deadly Ebola virus. Duration: 01:17 Video provided by AFP
Powered by NewsLook.com
These Popular Antibiotics Can Cause Permanent Nerve Damage

These Popular Antibiotics Can Cause Permanent Nerve Damage

Newsy (Mar. 27, 2015) — A popular class of antibiotic can leave patients in severe pain and even result in permanent nerve damage. Video provided by Newsy
Powered by NewsLook.com
WH Plan to Fight Antibiotic-Resistant Germs

WH Plan to Fight Antibiotic-Resistant Germs

AP (Mar. 27, 2015) — The White House on Friday announced a five-year plan to fight the threat posed by antibiotic-resistant bacteria amid fears that once-treatable germs could become deadly. (March 27) Video provided by AP
Powered by NewsLook.com
House Ready to Pass Medicare Doc Bill

House Ready to Pass Medicare Doc Bill

AP (Mar. 26, 2015) — In rare bipartisan harmony, congressional leaders pushed a $214 billion bill permanently blocking physician Medicare cuts toward House passage Thursday, moving lawmakers closer to resolving a problem that has plagued them for years. (March 26) Video provided by AP
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

 

Health & Medicine

Mind & Brain

Living & Well

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