Navigation Links
Overcoming anthrax bacterium's natural defenses could hold key to new treatments

Army scientists have discovered a way to "trick" the bacterium that causes anthrax into shedding its protective covering, making it easier for the body's immune system to mount a defense. The study, which appears in this month's issue of the journal MICROBIOLOGY, could lead to new approaches for treating anthrax infection.

Bacillus anthracis, the causative agent of anthrax, is particularly lethal because of its protective coating, or capsule, which enables the pathogen to escape destruction by the host's immune system. A key bacterial enzyme called capsule depolymerase, or CapD, anchors the capsule to the cell surface. CapD also cuts and releases part of the capsule into small fragments that are thought to interfere with specific parts of the immune system, offering further protection to the bacterium. The rest of the capsule remains intact.

Finding a way to cause B. anthracis to unmask itself, using the bacterium's own machinery, would be a novel approach to defeating the pathogen. So scientists at the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID) induced B. anthracis to make higher-than-normal amounts of CapD, resulting in release of the capsule fragments. This left very little capsule attached to the bacterial cells. As a result, the unprotected bacteria were left vulnerable to immediate detection and destruction by the cells of the immune system.

"By engineering B. anthracis to over-produce CapD, we are effectively turning the bacterium's own weapon on itself," explained Dr. Arthur Friedlander, one of the study's principal investigators. He believes the USAMRIID group's findings could have significant clinical impact.

"Many pathogenic bacteria, including B. anthracis, produce a capsule surrounding them that prevents the infected host from killing them, improving their chances of causing disease," he explained. "Understanding the mechanisms of virulence used by the anthrax bacterium is vital to developing medical countermeasures against it."

Anthrax most commonly occurs in wild and domestic mammals, although it has the potential to be used as a biological threat agent. Symptoms vary depending on the route of exposure; however, mild fever, fatigue and muscle aches usually begin within 4-6 days of exposure. As the bacteria multiply in the lymph nodes, toxemia progresses and the potential for widespread tissue dissemination, destruction and organ failure increases. Severe breathing difficulty, meningitis and shock can follow. Up to 90 percent of untreated cases of inhalational anthrax result in death.

"This study provides significant insight into the pathogenesis of anthrax infection, tracing the connection between B. anthracis gene expression to its effect on host response," said Colonel John P. Skvorak, commander of USAMRIID.


Contact: Caree Vander Linden
US Army Medical Research Institute of Infectious Diseases

Related biology news :

1. Overcoming Taboos, Myths, and Dogmas in Bioethics
2. Einstein scientists move closer to a safer anthrax vaccine
3. Single host gene may hold key to treating both ebola and anthrax infections
4. Early detection and quick response are key to defense against anthrax attack
5. Data published in the New England Journal of Medicine support use of raxibacumab (ABthrax) for the treatment of inhalation anthrax
6. Novel handheld device detects anthrax with outstanding accuracy and reliability
7. New technique used to profile anthrax genome
8. FBI unveils science of anthrax investigation
9. NIST, Army researchers pave the way for anthrax spore standards
10. New decontamination system kills anthrax rapidly without lingering effects
11. Anthrax cellular entry point uncovered
Post Your Comments:
(Date:11/11/2015)... 2015   MedNet Solutions , an innovative SaaS-based eClinical ... is pleased to announce that it will be a Sponsor ... event, to be held November 17-19 in Hamburg ... demonstrations of iMedNet , MedNet,s easy-to-use, proven ... has been able to deliver time and cost savings ...
(Date:11/10/2015)... Nov. 10, 2015 About ... that helps to identify and verify the identity ... considered as the secure and accurate method of ... a particular individual because each individual,s signature is ... especially when dynamic signature of an individual is ...
(Date:11/9/2015)... Calif. , Nov. 9, 2015  Synaptics Inc. ... interface solutions, today announced broader entry into the automotive ... solutions that match the pace of consumer electronics human ... biometric sensors are ideal for the automotive industry and ... Europe , ...
Breaking Biology News(10 mins):
(Date:11/25/2015)... 2 nouvelles études permettent d , ... les souches bactériennes retrouvées dans la plaque dentaire ... . Ces recherches  ouvrent une nouvelle voie ... de l,un des problèmes de santé les plus ... --> 2 nouvelles études permettent d , ...
(Date:11/25/2015)... ANGELES and HOLLISTON, Mass. ... Technology, Inc. (Nasdaq: HART ), a biotechnology company ... that CEO Jim McGorry will present at ... December 1, 2015 at 2:30 p.m. PT. The presentation ... below) for 30 days. Management will also be available ...
(Date:11/25/2015)... , Nov. 25, 2015 /PRNewswire/ - Aeterna Zentaris Inc. ... its business and prospects remain fundamentally strong and ... (zoptarelin doxorubicin) recently received DSMB recommendation to continue ... following review of the final interim efficacy and ... Primary Endpoint in men with heavily pretreated castration- ...
(Date:11/25/2015)... -- Orexigen® Therapeutics, Inc. (Nasdaq: OREX ) today ... discussion at the Piper Jaffray 27th Annual Healthcare Conference ... is scheduled for Wednesday, December 2, at 8:00 a.m. ... will be available for 14 days after the event.  ... Corporate Communications and Business Development , BrewLife(858) 875-8629 ...
Breaking Biology Technology: