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:2/1/2016)... Feb. 1, 2016  Wocket® smart wallet ( www.wocketwallet.com ) announces the ... Joey Fatone . Las Vegas , where ... --> Las Vegas , where Joey appeared at ... The new video ad was filmed at the Consumer Electronics Show (CES2016) ... Wocket booth to meet and greet fans. --> ...
(Date:1/22/2016)... January 22, 2016 ... addition of the  "Global Behavioral Biometric ... --> http://www.researchandmarkets.com/research/4lmf2s/global_behavioral ) has ... Behavioral Biometric Market 2016-2020"  report to ... and Markets ( http://www.researchandmarkets.com/research/4lmf2s/global_behavioral ) has announced ...
(Date:1/20/2016)... , Jan. 20, 2016  Synaptics Incorporated ... human interface solutions, today announced sampling of S1423, ... for wearables and small screen applications including smartwatches, ... printers. Supporting round and rectangular shapes, as well ... excellent performance with moisture on screen, while wearing ...
Breaking Biology News(10 mins):
(Date:2/11/2016)... Florida , February 11, 2016 ... PositiveID Corporation ("PositiveID" or "Company") (OTCQB: PSID), a ... announced today that its Thermomedics subsidiary, which markets ... on its growth plan in January 2016, including ... distributors, increasing sequential monthly sales growth, and establishing ...
(Date:2/11/2016)... , ... February 11, 2016 , ... ... medicine, has announced a new agreement with Bankok,Thailand-based Global Stem Cells Network (GSCN) ... phsyicians in 15 Latin American countries, including Mexico, Costa Rica, Dominican Republic, Colombia, ...
(Date:2/10/2016)... -- Early-career researchers from Indonesia ... Uganda and Yemen ...   Indonesia , Nepal , ... Yemen are being honored for their accomplishments in nutrition, ... for mentoring young women scientists who are pursuing careers in agriculture, biology ...
(Date:2/10/2016)... ASAE is introducing a hybrid membership model which will ... of joining or renewing through an organizational purchasing model. ... every employee in any size association or AMC office ... member benefits.   John H. Graham, IV ... allow organizations of any size and their employees to ...
Breaking Biology Technology: