Antivirals

Question 1

Different types of viruses that are nucleic acid coated in proteins.

Answer 1

DNA viruses, RNA viruses and retroviruses

DNA viruses (e.g., smallpox, herpes), translate the DNA into the mRNA of host

RNA viruses (e.g., COVID, influenza, measles) insert RNA, which acts as mRNA in the host

Retroviruses (e.g., HIV) DNA copy is made of the RNA by viral reverse transcriptase, and then the DNA is integrated into the hosts DNA.

Question 2

mechanism of viral infections

Answer 2

The virus encodes a number of proteins that complete specific tasks that hijack the host, to improve replication of the virus.

Protiens include reverse transcriptases, proteases, integrases (integrate genetic material into host genome), and inhibitor proteins (of DNA repair/immune system).

Question 3

HIV mechanism

Answer 3

9 genes that encode 20 proteins.

Enters into the cell using CD4 and CCR5/CXCR4 receptors.

Makes copy of DNA from RNA using viral reverse transcriptase, and then it is integrated into host DNA

Question 4

Drugs classes targeting HIV and their mechanisms

Answer 4

inhibiting entry:

CD4 inhibitors (enfuvirtide and fostemasavir) inhibit entry of HIV into cell.

CCR5/CXCR4 inhibitors (antibodies against it or block it) ex: maraviroc

fusion inhibitors

inhibiting functions in cell:

HIV reverse transcriptase inhibitors (e.g., nucleotides, nucleosides, and non-nucleosides) inhibit the production of the viral DNA from its RNA

HIV integrase inhibitors (e.g., raltegravir, dolutegravir, elvitegravir) inhibit the integration of the viral DNA into the host DNA

HIV protease inhibitors (e.g., ritonavir, lopinavir) inhibits the protein processing following transcription that is necessary for the HIV-encoded proteins to hijack the host

Question 5

Antivirals for COVID

Answer 5

Sotrovimab is a monoclonal antibody vaccine (no-longer used)

paxlovid is a protease inhibitor of protease for the translation of the proteins in the virus. Ritonavir has also been used

molnupiravir inhibits the replication of the proteins.

Question 6

How do nucleotides-looking compounds treat viruses

Answer 6

They can integrate into the RNA, inhibiting the proof reading of the RNA-replication enzyme. Inhibits transcription.

Remdesivir is a broad spectrum antiviral that utilises this mechanism.