Navigation Links
Defense mechanism against bacteria and fungi deciphered
Date:1/21/2011

Under standard laboratory conditions, the human beta-defensin 1 (hBD-1), a human antibiotic naturally produced in the body, had always shown only little activity against microbes. Nevertheless the human body produces it in remarkable quantities. The solution to the puzzle was the investigation process itself, as the research group led by Dr. Jan Wehkamp at the Dr. Margarete Fischer-Bosch Institute for Clinical Pharmacology of the Stuttgart-based Robert Bosch Hospital found out.

Before the research group took a new approach to this research, defensins were usually tested in the presence of oxygen, although little oxygen is present, for example, in the human intestine. Starting out from the discovery that a special antibiotic-activating protein of the human body is diminished in patients with inflammatory bowel diseases, Crohn's Disease and Ulcerative Colitis, the working group investigated how defensins act under low-oxygen conditions. During their investigations the scientists found out that under these conditions hBD-1 unfolds a strong antibiotic activity against lactic acid bacteria and yeast.

Furthermore the researchers discovered that another human protein, thioredoxin, is able to activate beta-defensin 1 even in the presence of oxygen. Moritz Marcinowski and Professor Johannes Buchner from the Department of Chemistry at the Technical University of Munich, used circular dichroism spectroscopy to elucidate the differences between the folded inactive and the unfolded active form of the protein.

Surprisingly, while almost all proteins are active only in their folded form, in the case of the small defensin the opposite is true. To activate the beta-defensin 1 the thioredoxin opens the three disulphide bridges that hold the molecule together. The molecule then opens up into the active state. Using this mechanism the body has the opportunity to selectively activate the defensin.

So far the cause of inflammatory bowel disease is unclear. Genetic as well as environmental factors seem to play a role, finally leading to a weakening of the antimicrobial barrier, which is mainly mediated by defensins. Accordingly the identified mechanism might contribute to the development of new therapies to treat affected patients.


'/>"/>

Contact: Dr. Andreas Battenberg
battenberg@zv.tum.de
49-892-891-0510
Technische Universitaet Muenchen
Source:Eurekalert  

Related biology news :

1. Scientists pinpoint key defense against parasite infection
2. SAIC Awarded $23 Million Task Order by Defense Biometrics Identity Management Agency
3. Lockheed Martin and ZyGEM Accelerate DNA Identification for Law Enforcement, Homeland Security and Defense Communities
4. Lockheed Martin and ZyGEM Accelerate DNA Identification for Law Enforcement, Homeland Security and Defense Communities
5. Macrophages: The defense cells that help throughout the body
6. Case Western Reserve awarded $4.7 million from Defense Advanced Research Projects Agency
7. Self-defense strategies of moss
8. Overcoming anthrax bacteriums natural defenses could hold key to new treatments
9. Defense-scale supercomputing comes to alternative energy research
10. ARES Aerospace and Defense Division Receives AS9100 Certification
11. Scientists crack code of critical bacterial defense mechanism
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Defense mechanism against bacteria and fungi deciphered
(Date:6/20/2016)... , June 20, 2016 Securus ... justice technology solutions for public safety, investigation, corrections ... the prisons involved, it has secured the final ... (DOC) facilities for Managed Access Systems (MAS) installed. ... additional facilities to be installed by October, 2016. ...
(Date:6/15/2016)... , June 15, 2016 ... report titled "Gesture Recognition Market by Application Market - Global Industry ... - 2024". According to the report, the  global gesture ... in 2015 and is estimated to grow at ... billion by 2024.  Increasing application of ...
(Date:6/9/2016)... TURKU, Finland , June 9, 2016 ... French National Police deploy Teleste,s video security solution to ensure ... France during the major tournament ... and data communications systems and services, announced today that its ... Police Prefecture to back up public safety across ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... LOUISVILLE, Ky. , June 23, 2016 /PRNewswire/ ... from two Phase 1 clinical trials of its ... double-blind, placebo-controlled, single and multiple ascending dose studies ... and pharmacodynamics (PD) of subcutaneous injection in healthy ... APL-2 subcutaneously (SC) either as a single dose ...
(Date:6/23/2016)... LONDON , June 23, 2016 ... & Hematology Review, 2016;12(1):22-8 http://doi.org/10.17925/OHR.2016.12.01.22 ... Review , the peer-reviewed journal from touchONCOLOGY, ... the escalating cost of cancer care is placing ... a result of expensive biologic therapies. With the ...
(Date:6/23/2016)... ... 23, 2016 , ... ClinCapture, the only free validated electronic ... showcase its product’s latest features from June 26 to June 30, 2016 for ... Disrupting Clinical Trials in The Cloud during the conference. DIA (Drug Information ...
(Date:6/23/2016)... ... June 23, 2016 , ... Velocity Products, a division ... tuned and optimized exclusively for Okuma CNC machining centers at The International Manufacturing ... collaboration among several companies with expertise in toolholding, cutting tools, machining dynamics and ...
Breaking Biology Technology: