Hi Everyone. As a microbiology student today i share with you some microbiological topic with you. It's about prion and viroid.
Prions are infectious protein particles. It's weight is 3000 daltons. Its composed of around 253 amino acid. Prions are di not contain DNA or RNA. Prion are smaller than viroids, size is around 2.0 nm. Prions were discovered by stanley B.Prusiner.
Prions are infect animal. Prions causes diseases such as mad cow disease in cows, scrapie disease in sheep and goats etc.
Viroids are small and naked infectious RNA molecules. Its weight is 85,000- 1,30,000 daltons. Viroids were named by T.O.Diener in 1971. Viroids are smaller than viruses size is around 20 nm.
Vitoids infect higher plants. Viroids cause diseases such as potato spindle tuber disease in potato, Tomato cadang cadang disease in tomato etc.