Navigation Links
Hijacked supplies for pathogens
Date:7/23/2010

When it infects the lungs, the Legionnaire's bacterium Legionella pneumophila causes acute pneumonia. The pathogen's modus operandi is particularly ingenious: it infiltrates deliberately into cells of the human immune system and injects a host of proteins which then interfere in the normal cellular processes. Scientists from the Max Planck Institute of Molecular Physiology in Dortmund have now discovered how Legionella reprogrammes the cells to ensure its own survival and to propagate. They examined a protein used by the pathogen to divert the material transport within the cells for its own purposes. (Science, July 22, 2010)

During a Legionella infection, the bacteria are engulfed by immune cells and bound by a membrane in the cell interior. Legionella protects itself against destruction by releasing proteins that reprogramme the human cell and exploit it for its own purposes. One of these proteins is DrrA. Previous studies succeeded in demonstrating that DrrA diverts the material transport in human cells in the direction of the pathogen, using what are known as Rab proteins for this purpose.

Rab proteins are switch molecules that coordinate transport vesicles within cells. In this capacity, they ensure that these membrane-bound vesicles reach the correct destination at the right time. Of the total of 60 different Rab proteins, DrrA specifically uses the Rab1 molecule for its own purposes: it deposits Rab1 on the membrane enclosing the bacteria and activates it. As a result, part of the material transport of the human cell is diverted to the vesicle containing the bacterium.

The structural and biochemical analysis of DrrA led the Dortmund-based scientists to make an astonishing discovery: DrrA is not only capable of activating Rab1, it also appears to be able to extend its activated state. To this end, DrrA blocks the switching-off of Rab1 and the necessary recognition site for regulatory proteins by attaching an AMP molecule to Rab1. "The permanent activation of Rab1 by DrrA could ensure increased material transport in the direction of the Legionella containing compartment and hence support its survival," concludes Aymelt Itzen from the Max Planck Institute of Molecular Physiology.

"These results represent an example of how the molecular analysis of bacterial diseases can help us not only to understand the cellular mechanisms involved in an infection, but also the functioning of healthy cells," explains Roger Goody from the Dortmund Institute. In the case of Legionnaire's disease, the study of the bacterial protein DrrA reveals how a human regulatory protein (Rab1) is activated in a targeted way and maintained in an active state. This raises the question as to whether Legionella devised this kind of regulation or whether healthy cells can also control material transport in a similar but hitherto unknown way.


'/>"/>

Contact: Dr. Peter Herter
peter.herter@mpi-dortmund.mpg.de
49-231-133-2500
Max-Planck-Gesellschaft
Source:Eurekalert  

Related biology news :

1. Healthy watersheds can sustain water supplies, aquatic ecosystems in a changing climate
2. Killer bees may increase food supplies for native bees
3. ORNL scientists hone technique to safeguard water supplies
4. Targeting children effective use of limited supplies of flu vaccine and could help control flu spread
5. Scientists urge global action to preserve water supplies for billions worldwide
6. Turning over a new leaf for future energy supplies
7. Polarized light guides cholera-carrying midges that contaminate water supplies
8. Soil-borne pathogens drive tree diversity in forests, study shows
9. Neiker-Tecnalia underlines the need to maintain programs for monitoring pathogens in wildlife
10. Genomes of citrus canker pathogens decoded
11. New technology enables machines to detect microscopic pathogens in water
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Hijacked supplies for pathogens
(Date:5/16/2016)... --  EyeLock LLC , a market leader of iris-based ... IoT Center of Excellence in Austin, Texas ... embedded iris biometric applications. EyeLock,s iris authentication ... with unmatched biometric accuracy, making it the most proven ... platform uses video technology to deliver a fast and ...
(Date:4/28/2016)... First quarter 2016:   , Revenues amounted to ... of 2015 The gross margin was 49% (27) ... operating margin was 40% (-13) Earnings per share rose ... was SEK 249.9 M (21.2) , Outlook   ... The operating margin for 2016 is estimated to exceed ...
(Date:4/15/2016)... 15, 2016 Research and ... Biometrics Market 2016-2020,"  report to their offering.  , ... , ,The global gait biometrics market is expected ... the period 2016-2020. Gait analysis generates ... be used to compute factors that are not ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... ... 2016 , ... While the majority of commercial spectrophotometers and fluorometers use the ... models are higher end machines that use the more unconventional z-dimension of 20mm. ... the bottom of the cuvette holder. , FireflySci has developed several Agilent flow ...
(Date:6/23/2016)... , June 23, 2016 /PRNewswire/ - FACIT has ... Ontario biotechnology company, Propellon Therapeutics Inc. ... and commercialization of a portfolio of first-in-class WDR5 ... targets such as WDR5 represent an exciting class ... in precision medicine for cancer patients. Substantial advances ...
(Date:6/23/2016)... 2016  The Biodesign Challenge (BDC), a university competition ... harness living systems and biotechnology, announced its winning teams ... New York City . The ... projects at MoMA,s Celeste Bartos Theater during the daylong ... senior curator of architecture and design, and Suzanne ...
(Date:6/23/2016)... 2016 Apellis Pharmaceuticals, Inc. today announced ... of its complement C3 inhibitor, APL-2. The trials ... dose studies designed to assess the safety, tolerability, ... in healthy adult volunteers. Forty subjects ... single dose (ranging from 45 to 1,440mg) or ...
Breaking Biology Technology: