The new type H toxin was found in the feces of a child with the disease, according to Stephen Arnon and his colleagues at the California Department of Public Health in Sacramento. They reported their results this week.
The toxin is so deadly, in fact, that simply sniffing it at a dose of billionths of a gram can be lethal. Worse, an injection of only 2-billionths of a gram can kill. For comparison, arsenic , one of the most popular fatal poisons, is lethal at only one-tenth of a gram. Traditional antibodies were only mildly effective at degrading the toxin, and no protective effects were observed when experimenters administered types A-G antibodies to mice or rabbits with the type H toxin.
This is the first time scientists have withheld the gene sequence of a newly discovered substance. Normal protocol dictates researchers publish the data in a public database, called GenBank , but because the toxin is so lethal, it was decided the move was too risky.
These included the infectious disease laboratory at the U. Deadly diseases and toxins routinely pose such a moral threat to scientists, who must decide whether the general public will potentially benefit or suffer from the DNA information being made available. This was the case last year when Stanford University researcher David Relman was one of six members of a U. The popular cosmetic treatment known as Botox utilizes a weak form of the toxin, type A, as its chief ingredient.
Of the current toxin, Relman said releasing the sequencing would be, according to New Scientist , "an immediate and unusually serious risk to society. Botox may be used alone or with other medications.
Botox is a Neuromuscular Blocker, Botulinum Toxin. Botulinum toxin Scientists differ about the relative toxicities of substances, but they seem to agree that botulinum toxin, produced by anaerobic bacteria, is the most toxic substance known.
Its LD50 is tiny — at most 1 nanogram per kilogram can kill a human. Moreover, as your muscles become weaker, they can start to recruit surrounding muscles when you make facial expressions. There is nothing harmful about stopping Botox. Nor are there any dangerous or negative side effects. Your muscles will simply not be as relaxed.
You will have total mobility of the treated area, regardless of how long you received Botox injections. Once the toxin links to this second receptor, it can enter the nerve cell and break a protein needed to deliver molecules that can signal other nerve cells.
By blocking this signaling molecule, tiny amounts of botulinum toxin can cause paralysis and even death through respiratory failure. The bacteria that makes this toxin grows in soil, and can be found inside cans of food that were improperly processed.
Botulinum toxin is the reason for the extreme danger from bulging cans of food. Researchers have been working on the unique nerve-blocking ability of the seven individual botulinum toxins for decades, says botulinum expert Edwin Chapman, UW-Madison professor of physiology and a Howard Hughes Medical Institute investigator.
The research was a close collaboration with Ray Stevens of Scripps, who crystallized the structure that forms when botulinum toxin links to the protein receptor on a nerve cell. This is a snapshot of the first stage of that poisoning. The report on the work, in the journal Nature this week, identified a short section on the protein receptor as the exact spot where botulinum toxin grips the cell immediately before entering it. UW-Madison has long been a center of botulism research. In , Min Dong, a post-doctoral fellow in Chapman's lab, showed that a known protein receptor for one botulinum toxin was a key point of entry into the nerve cell.
The Nature paper is an elaboration on that discovery, which was published in The Journal of Cell Biology.
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