Prions exist normally as innocuous cellular proteins. Like all proteins, prion is made up of a sequence of amino acids, and the DNA of the animal host controls the sequence. It is a protein found in nerves and the brain. The causative agent is usually transferred with food. Prion infection is not sensitive to radiation treatment that damages virus genome.
Prions are sensitive to protein denaturing agents, such as phenol and urea.
Prions withstand normal steam sterilization and use of disinfectants. Prusiner took up the challenge to precisely identify the infectious agent and ten years later, in 1982, he and his colleagues successfully produced a preparation derived from diseased hamster brains that contained a single infectious agent. The evidence indicated that the infectious agent was a single protein. In 1997, Nobel Prize in Physiology or Medicine was awarded to Stanley Prusiner for his discovery of an entirely new genre of disease-causing agents and the elucidation of the underlying principles of their mode of action. The prion gene is found in animals, including humans.