Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Anthrax action shapes up

24.10.2001


Anthrax is under close scrutiny.
© AP/Fort Detrick, US Army


Washington’s Dirkin Senate Office gets a careful clean-up.
© AP/Kenneth Lambert


Researchers find two new leads for anti-anthrax drugs.

As fears over bioterrorism attacks spiral, researchers are making progress towards better anthrax drugs - but these are unlikely to reach the drugstore soon.

Of ten confirmed anthrax cases in the United States by Monday, four have been of the severe, inhaled form against which antibiotics often fail. By the time drugs destroy the bacteria responsible, Bacillus anthracis, the organisms have released enough lethal toxin to kill immune cells in the blood, causing fatal blood poisoning.



Two new discoveries lay the groundwork for drugs that could disable the toxin and, along with antibiotics, save lives.

John Young, of the University of Wisconsin in Madison, and his colleagues have pinpointed the protein, on the surface of human cells, which the anthrax toxin latches onto1. In the lab a synthetic version of this ’receptor’ mops up the poison and protects cells. "It serves as a decoy," Young explains.

Part of the toxin attaches to this receptor, punches a hole in the human cell membrane and injects another part, the ’lethal factor’, which destroys proteins in the cell. A second team, led by Robert Liddington of The Burnham Institute in La Jolla, California, have deduced the structure of this lethal factor2.

With a picture of how the toxin’s proteins attack cells, drug companies can search for chemicals that block their activity, the teams hope.

This promise is unlikely to be realized in time to help the current situation, Young and Liddington caution - most optimistic estimates are that improvements will be a year in the making. "We need to design drugs - not for this time round but for the next one," says Liddington.

Alternative medicine

The current crisis gives the hunt for effective treatments new urgency. What we have is no longer "state-of-the-art", says Richard Corlin, director of the American Medical Association in Chicago, Illinois. The latest work "will lead us to a better treatment", he agrees.

Excessive use of an existing antibiotic, ciprofloxacin, could create its own medical problems, Corlin warns. The drug destroys healthy bacteria in the body, so may leave people open to infection from other pathogens.

Overuse of antibiotics and failure to complete the 60-day course virtually "guarantee the emergence of antibiotic resistant strains" of these pathogenic bacteria, he says, making such infections difficult to treat.

Bioterrorists could potentially engineer antibiotic-resistant anthrax. Manufacturing bacteria able to withstand toxin-targeted drugs would be "almost impossible", says John Collier of Harvard Medical School, who contributed to both studies. It would require expert biochemical knowledge to alter specific protein shapes and interactions.

The anthrax vaccine is also problematic. Developed in the 1960s, it involves injecting a crude mix of the toxin’s protein components to stimulate resistance. Vaccination requires six shots and regular boosters. The vaccine is currently produced only in sufficient quantities for the US military.

Several groups are designing more effective versions using purified proteins, explains anthrax researcher Stephen Leppla of the National Institute of Dental and Craniofacial Reseach in Bethesda, Maryland. These are easily administered and produce long-lasting immunity. "Before too long, we’ll have it," he predicts.

Ultimately, we need a whole new arsenal to fight anthrax, says Collier - a new antibiotic, a safe, efficient vaccine, and drugs against toxins. Realizing this goal requires further funding for research and fast-track approval of candidate drugs, he suggests.

Meanwhile most people agree that heightened awareness remains the best form of defence, catching early, cold-like symptoms in time for the disease to be treated. "The key thing is an appropriate degree of surveillance," says Corbin.

Spore show

Anthrax spores, the persistent, dormant form of the bacterium, can cause infection through the skin and intestine, but inhalation is the most dangerous - around 90% of cases result in death.

Turning anthrax into an effective bioweapon is technically difficult - spores must be milled down into a very fine powder (less than 5 micrometres in diameter) for them to reach the depths of the lungs in sufficient quantities to cause infection. A dose of around 10,000 spores is thought to cause a lethal infection.

Spores sent in letters to media and political organizations in the United States had produced ten confirmed cases by the end of Monday, including one death. The deaths of two more postal workers have been linked to the disease. The source of the letters has not yet been found, and the United States is offering a $1-million reward for information leading to the identification of those responsible.

References
  1. Bradley, K.A., Mogridge, J., Mourez, M., Collier, R.J. & Young, J.A.T. Identification of the cellular receptor for the anthrax toxin. Nature, (2001).

  2. Panniter, A. et al. Crystal structure of the anthrax lethal factor. Nature, (2001).


HELEN PEARSON | Nature News Service
Further information:
http://www.nature.com/nsu/011025/011025-9.html
http://www.nature.com/nsu/

More articles from Health and Medicine:

nachricht A promising target for kidney fibrosis
21.04.2017 | Brigham and Women's Hospital

nachricht Stem cell transplants: activating signal paths may protect from graft-versus-host disease
20.04.2017 | Technische Universität München

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

DGIST develops 20 times faster biosensor

24.04.2017 | Physics and Astronomy

Nanoimprinted hyperlens array: Paving the way for practical super-resolution imaging

24.04.2017 | Materials Sciences

Atomic-level motion may drive bacteria's ability to evade immune system defenses

24.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>