Viruses
Viral Structure
Viruses have small genetic material (DNA or RNA [never both]). The genome, or genetic material, is sourrounded by a protective protein layer called the capsid. The size of the capsid dictates the quanity of genetic information that can be packaged in a viral particle. An envelope is a lipid bilayer that is derived from the host cell membrane during virus budding. Envelopes are not in all viruses. Viruses that have envelopes are less stable than the ones without.
Types of Viruses
The grouping of viruses is based on their shape and structure,if they contain a capsid and/or an envelope and if they consist of either DNA or RNA. One type of virus is the DNA virus which produces RNA to make viral proteins or to join host cells DNA, making new viruses. Another type of virus is the RNA virus. In the RNA virus, the RNA goes to the cytoplasm to produce viral proteins. In addtion, there is the inactivated virus which does not replicate in the host cell. Also, there is the attenuated virus that replicates but does not cause any disease. Furthermore, there is the Retrovirus that contains enzyme reverse transcriptase alongside with RNA. Additionaly, there are viroids which is the smallest known reproducing particle. They are short, single strand RNA with no capsids. They are known to disrupt cells' metabolism. Moreover, there are also prions that are irregular forms of proteins that clump together in brain cells. It defeats cells by blocking their molecular traffic.
Head (Capsid)
Tail
Tail Fibers
How a Virus Invades Your Body...
1798 is when the first successful viral vaccination was created by a man named Edward Jenner. The viral disease was smallpox; it spread through Asia to the Americas. He developed the vaccination from studying people with Cowpox and realized that those people later on couldn't contract smallpox. He then inoculated the people with cowpox to prevent smallpox. It modified how a person was treated with a virus unlike back in the day when they just isolated that person and hoped they'd live through the diesease, they can now prevent or treat the symptoms for the virus. Viral vaccination has changed traditional technologies in the sense that companies can combine gene-sequenced DNA to create a stable format for vaccinations. The major challenge for viral research is viruses themselves. A virus has a capsid that protects it from and viruses can attack a cell without leading to visible syptoms. Also a virus has many strains, so getting a vaccination for one strain of a virus may contract the same viral disease but with a different strain. This application is still under some development, for example HIV phase 1, Hepatitis B, and strains of Influenza are the under the most development in many biotech companies.
