How are viruses and prions different?

Answer 1

Prions are infectious agents composed exclusively of a single sialoglycoprotein called PrP 27-30. They contain no nucleic acid. PrP 27-30 has a mass of 27,000 - 30,000 daltons and is composed of 145 amino acids with glycosylation at or near amino acids 181 and 197. The carboxy terminus contains a phosphatidylinositol glycolipid whose components are ethanolamine, phosphate, myo-inositol and stearic acid. This protein polymerizes into rods possessing the ultrastructural and histochemical characteristics of amyloid. Amyloid is a generic term referring to any optically homogenous, waxy, translucent glycoprotein; it is deposited intercellularly and/or intracellularly in many human diseases such as:

• Alzheimer's disease
• Creutzfeldt-Jakob disease
• Down's syndrome
• Fatal familial insomnia
• Gerstmann-Straussler syndrome
• Kuru Leprosy

Viroids are infectious agents composed exclusively of a single piece of circular single stranded RNA which has some double-stranded regions.

• Because of their simplified structures both prions and viroids are sometimes called subviral particles. Viroids mainly cause plant diseases but have recently been reported to cause a human disease.

  Catalytic RNAs are those that have the intrinsic ability to break and form covalent bonds; Viroids are catalytic RNA's (ribozymes) that cleave RNA to produce fragments containing a 5'-hydroxyl and a 2', 3'-cyclic phosphate.

Answer 2

Viruses are non cellular infectious entities which possess DNA or RNA as heredity material enclosed in a protein capsid. Different viruses attack plants animals and bacteria and cause diseases.Viruses are intermediate between living and non living things.

Prions are protein molecules discovered in 1983 that cause mad cow disease and brain infection.They are self replicating by unknown mechanism.

Answer 3

A virus is a small packet of nucelic acid that can insert itself into the host DNA and alter its function to make more copies of the virus which then can spread to other hosts. A prion is a mis-folded protein ie it is not nucelic acid. Quite how it becomes infectious is beyond this little black duck.

Answer 4

Prions are different because they do not infect and replicate in the same way that viruses do. Viruses have RNA or DNA components and use body cells to replicate in. Prions are infectious proteins and they cause a structural change to other proteins that they interact with and that is how they cause damage. Probably the most famous prion disease is Bovine Spongiform Encephalitis (mad cow) where the structural change that the prion causes to the proteins in the brain causes holes to appear in the tissue, making it look like a sponge.

Answer 5

As far as I know, a plasmid and a virus both consist of small lengths of nucleic acid chains, however a plasmid is confined to a living cell, whereas a virus can have a protective protein coat to protect it in the outside environment and to allow it to be transmitted to other uninfected cells. I think that they both can replicate with cell division.

Answer 6

viruses are genetic elements that contain DNA or RNA as their genetic material,and have an extracellular form. Plasmids do not have an extracellular form. Plasmids only have DNA.

Answer 7

Prions do not have any DNA or nucleic acid, but viroid's contain both. This is the primary difference between the two.

Answer 8

Prions lack genetic material such as RNA or DNA