第3期:认识细菌(3)

They also keep us healthy by occupying spaces that otherwise might be occupied by disease-causing bacteria. But even good bacteria like E-coli can develop deadly strains.

Bacteria are good or bad and sometimes they are both. Remember Saddam Hussein's biological Arsenal, he raised bacteria with the graceful name of Clostridium botulinum.

It causes botulism a kind of food poisoning we got to know - well before processing methods were improved. When we eat it, we get deathly ill and we die.

It's a very it's about as potent a poison as is known actually pound for pound. It will kill more things than anything else.

Six million times more deadly than rattlesnake venom, it is the most toxic substance on earth. Botulinum toxin could be such a powerful weapon that it's been drafted for war since the 1940s.

Scientists suspected there might be a use for the toxin. Schatz began his study of the toxin while working for Army Intelligence during World War two.

Until his retirement he supplied all the botulinum toxin used in scientific and medical research in the nation. Eric Johnson has worked with him for the past 13 years.

We purify it by several purification steps and there's I would say 50 milligrams of toxin and this vial here which is maybe a million lethal doses. So obviously we're very careful with how we handled on a sample.

After all his years of research Dr. Schatz had the imagination to see another application for the toxin. At first it started with a small bit of pain at the base of the neck and then eventually as I'd be driving the car all of a sudden my head would go to the left.

And the only way I could get it back was to take my hand and push it back.