 |
|
Ricin's Deadly Action Revealed by Glowing Probes
August 07, 2008A new chemical probe can rapidly detect ricin, a deadly poison with no known antidote that is feared to be a potential weapon for terrorists and cannot quickly be identified with currently available tests.
The probe, developed by chemists at UC San Diego, glows when bound to a ricin-damaged part of the body's protein-making machinery, they report in the international edition of the journal Angewandte Chemie. Because the test pinpoints the specific injury underlying the poison's toxicity, it could also help to develop drugs to counteract the effect of ricin.
Ricin toxin is among the most deadly. Just 400 micrograms, about the size of a grain of salt, is enough to kill an adult, according to a report by the Congressional Research Service. Several other toxins including saporin and sarcin all cause harm in similar ways.
These poisons nick a crucial loop of RNA that is part of the cellular structure that synthesizes proteins called the ribosome. That small alteration, the loss of a single piece at the apex the loop, is enough to shut down the manufacture of proteins. Damage of this type is unusual in the absence of these specific toxins.
"We found a chemical reporter that detects a relatively rare event, one that is related to the action of the toxin," said Yitzhak Tor, a professor of chemistry and biochemistry at UCSD.
Tor, along with postdoctoral researcher Seergazhi Srivatsan and graduate student Nicholas Greco, created a short string of RNA building blocks, or nucleotides, that will attach to the loop. At one position, matching the site ricin damages, they substituted a synthetic nucleoside that glows when the piece that belongs there is missing. If the toxin has damaged the loop, ultraviolet light shone on the sample will fluoresce bright blue.
"Our reporter probe shows that the reaction is taking place," Tor said. "When there's no toxin, there will be no light emission."
Ricin worries security experts because the toxin, an extract of castor beans, is relatively easy to make and difficult to detect. Right now, tests rely on antibodies that recognize the ricin toxin protein itself, which take at least 48 hours to complete, according to the Centers for Disease Control and Prevention. The new test works quickly; it can reveal the presence of damaged ribosome loops in less than 30 minutes.
Tor's team has developed their probe using isolated RNA loops. These will be the basis for the future design of a sensitive chip that could be used in the field to detect quickly the presence of dangerous toxins.
And because their probe detects the action, rather than merely the presence of the toxin, it could be used to develop ways to help people who have been exposed, Tor said. "Now that we have an assay that senses the toxin's activity, we can try to discover inhibitors of the toxin or antidotes."
The National Institute for General Medical Sciences funded this research.
University of California, San Diego
These poisons nick a crucial loop of RNA that is part of the cellular structure that synthesizes proteins called the ribosome. That small alteration, the loss of a single piece at the apex the loop, is enough to shut down the manufacture of proteins. Damage of this type is unusual in the absence of these specific toxins.
"We found a chemical reporter that detects a relatively rare event, one that is related to the action of the toxin," said Yitzhak Tor, a professor of chemistry and biochemistry at UCSD.
Tor, along with postdoctoral researcher Seergazhi Srivatsan and graduate student Nicholas Greco, created a short string of RNA building blocks, or nucleotides, that will attach to the loop. At one position, matching the site ricin damages, they substituted a synthetic nucleoside that glows when the piece that belongs there is missing. If the toxin has damaged the loop, ultraviolet light shone on the sample will fluoresce bright blue.
"Our reporter probe shows that the reaction is taking place," Tor said. "When there's no toxin, there will be no light emission."
Ricin worries security experts because the toxin, an extract of castor beans, is relatively easy to make and difficult to detect. Right now, tests rely on antibodies that recognize the ricin toxin protein itself, which take at least 48 hours to complete, according to the Centers for Disease Control and Prevention. The new test works quickly; it can reveal the presence of damaged ribosome loops in less than 30 minutes.
Tor's team has developed their probe using isolated RNA loops. These will be the basis for the future design of a sensitive chip that could be used in the field to detect quickly the presence of dangerous toxins.
And because their probe detects the action, rather than merely the presence of the toxin, it could be used to develop ways to help people who have been exposed, Tor said. "Now that we have an assay that senses the toxin's activity, we can try to discover inhibitors of the toxin or antidotes."
The National Institute for General Medical Sciences funded this research.
University of California, San Diego
Ricin Current Events and Ricin News RSSArgonne researchers develop method that aims to stabilize antibodies
Researchers at the U.S. Department of Energy's Argonne National Laboratory have developed a systematic method to improve the stability of antibodies.
Green industrial lubricant developed
A team of researchers from the University of Huelva has developed an environmentally-friendly lubricating grease based on ricin oil and cellulose derivatives, according to the journal Green Chemistry.
NIST researchers 'all aglow' over new test of toxin strength
A new National Institute of Standards and Technology (NIST) assay using a "glow or no glow" technique may soon help the U.S. Department of Homeland Security (DHS) defend the nation against a spectrum of biological weapons that could be used in a terrorist attack.
What are protective effects of anti-ricin A-chain aptamer?
Ricin, a lectin from the castor bean plant Ricinus communis is considered one of the most potent plant toxins. Ricin poisoning can cause severe tissue damage and inflammation and can result in death.
Human trial proves ricin vaccine safe, induces neutralizing antibodies; further tests planned
cientists have completed the first human clinical trial of a recombinant vaccine for the deadly toxin ricin-a potential bioterror threat - and the results indicate the vaccine is safe and effective in eliciting ricin-neutralizing antibodies.
Artificial membranes can reveal biological weapons
Today there is a great need for portable equipment that can quickly detect chemical and biological weapons such as nerve gases, viruses, bacteria, and toxins. In a new dissertation the Swedish researcher Inga Gustafsson shows that artificial membranes can be used for this purpose in future biosensors. Biosensors have already proven to be useful in the detection of impurities in food and water, for example. They have also been used in industrial processes, clinical analyses, and the development of pharmaceuticals. In her dissertation, Inga Gustafsson, Department of Chemistry, Ume'å University, and FOI, the Swedish Defence Research Agency , studies artificial membran
Shield against assassin`s poison
Just a trace of ricin on the sharpened tip of an umbrella was enough to kill the Bulgarian dissident Georgi Markov, after an infamous attack on London`s Waterloo Bridge in 1978. Now a vaccine against this lethal toxin could soon be available - and it may be needed. "A big stash of ricin was found in the caves of Afghanistan," says Ellen Vitetta of the University of Texas Southwestern Medical Center in Dallas, whose team developed the vaccine. "They weren`t collecting it to make stew." Ricin, a natural toxin found in castor beans, is cheap and relatively easy to produce. And as it`s a powder, it is easily turned into an aerosol that can be inhaled. Nor does it take much to kill someone: just
The Biochemist February 2002 issue; THEME: Pretty poisonous
Introduction - The darker end of the spectrum The 'pretty poisonous' entities that are the subject of this issue of The Biochemist have a much darker side - they might be subject to misuse by those with malevolent intent. Toxins and bioregulators have certainly been considered and developed as weapons by some. In the late 20th Century, third-generation biological warfare programmes, such as in the former Soviet Union, used genetic engineering to modify classical agents. Could the knowledge gained by the genomics revolution be misused? An essential factor in preventing this, says Professor Malcolm Dando (Professor of International Security), is that scientists become much more aware of, and c
BBSRC announces its new ROPA awards
The Biotechnology and Biological Sciences Research Council (BBSRC) has announced its 1998 round of Realising Our Potential Awards (ROPAs). BBSRC is making 40 awards under the updated scheme in which awards can be made across all areas of research in each Research Council. The full list of BBSRC awards appears on pp10-11 of the current issue of bbsrc business. Projects of particular interest include: 1. Improving salt tolerance in plants Usually plants will not grow very well in salty conditions. By understanding how plants cope with excess salt scientists may be able to modify them to grow better in adverse saline conditions. This could have significant implications for increased crop prod
More Ricin Current Events and Ricin News Articles
 |
Silent Death, Second Edition by Uncle Fester (Author) This book details the home or clandestine manufacture of poisonous materials, with an emphasis upon guerrilla war applications. Topics covered in detail include nerve gases, ricin, botulin toxin, and much more. The Aum cult in Tokyo used this book as their lab manual. |
 |
Rossini: Piano Works 2 Gioachino Rossini (Composer), Stefan Irmer (Composer) |
 |
Giant Zanzibar Castor Bean 7 Seeds by Hirts Gardens THE CASTOR BEAN is a shrub-like plant with large, long-stemmed leaves that are lobed like fingers. Its spiny, clustered seed pods contain white, bean-like seeds (Botanically speaking, it isn't a true bean, but a Spurge), which typically bear attractive markings in various colours. The plant is native to tropical Africa, but it is grown commercially in California and has become naturalized throughout the southern United States. In northern areas, it is often cultivated, in the warmer months, as an ornamental annual in gardens, providing local gardeners with a castor of thousands.... Giant Zanzibar is a larger variety than common castor bean with more conspicuous veining on the leaves. This is a fast growing plant with huge, palmate, tropical-looking leaves up to three feet across. In... |
![Ricin [Explicit]](http://ecx.images-amazon.com/images/I/51b2evx9eeL._SL160_.jpg) |
Ricin [Explicit] National Lampoon Comedians (Primary Contributor) |
 |
21st Century Complete Guide to Ricin Terrorism and Defense Against Toxin Weapons (Essential NBC Reference Series: Bioterrorism, Nuclear, Biological, Chemical, ... Destruction WMD, First Responder Ringbound) by Department of Defense (Author) This is an up-to-date compendium of authoritative documents and text excerpts from major federal government sources on ricin terrorism, along with a full reproduction of a major military manual on toxins as weapons. Ricin toxin, found in the bean of the castor plant, Ricinis communis, is one of the most toxic and easily produced plant toxins. The toxicity of castor beans has been known since ancient times, and more than 750 cases of intoxication in humans have been described. Although ricin's lethal toxicity is approximately 1,000-fold less than that of botulinum toxin, ricin may have significance as a biological weapon because of its heat stability and worldwide availability, in massive quantities, as a by-product of castor oil production. RICIN (AND ABRIN) TERRORISM... |
|
Le Ricin by Marcel and Eberhardt, Philippe Dubard (Author) | |
![Rossini: Gymnastique d'Ècartement [Hybrid SACD]](http://ecx.images-amazon.com/images/I/513TKQ2AKKL._SL160_.jpg) |
Rossini: Gymnastique d'Ècartement [Hybrid SACD] Gioachino Rossini (Composer), Paolo Giacometti (Composer) |
 |
Red Leaf Castor Bean 10 Seeds by Hirt's Gardens In frost-free areas, castor bean is an evergreen herbaceous or semi-woody large shrub or small tree that gets up to 40' tall and 15' wide. In the tropics, it can have a trunk that is woody near the base and up to a foot in diameter. Elsewhere, castor bean plant grows as an annual that can get 4-15' tall in a single growing season. This is a fast growing, suckering, colony forming plant with decidedly tropical looking foliage. They tend to grow straight up at first, developing branches only later in the season (and in subsequent years for plants that live that long). The huge leaves are palmate, with 5-11 deeply incised lobes. They are glossy purplish or reddish-green and 12-30" across, with long petioles (leaf stems). The stems are watery juicy and reddish or purplish too. The flowers are... |
 |
Ricin (Daylight Gathering) Jack Bruce (Primary Contributor) |
|
Ricin Investigation.(Investigations): An article from: FBI Laboratory Annual Report by Federal Bureau of Investigation (Publisher) This digital document is an article from FBI Laboratory Annual Report, published by Federal Bureau of Investigation on January 1, 2003. The length of the article is 410 words. The page length shown above is based on a typical 300-word page. The article is delivered in HTML format and is available in your Amazon.com Digital Locker immediately after purchase. You can view it with any web browser. Citation Details Title: Ricin Investigation.(Investigations) Publication: FBI Laboratory Annual Report (Report) Date: January 1, 2003 Publisher: Federal Bureau of Investigation Page: 1 Distributed by Thomson Gale |
| © 2009 BrightSurf.com |