What do nucleoside analogs inhibit?
Nucleoside analogs are synthetic, chemically modified nucleosides that mimic their physiological counterparts (endogenous nucleosides) and block cellular division or viral replication by impairment DNA/RNA synthesis or by inhibition of cellular or viral enzymes involved in nucleoside/tide metabolism (Figure 1).
What is the result of a nucleoside analog?
The nucleoside analogues resemble naturally occurring nucleosides and act by causing termination of the nascent DNA chain. They are believed to inhibit viral replication by several mechanisms, either by competitive inhibition of the viral polymerase or by DNA chain termination.
How does nucleoside analogs alter DNA?
Nucleoside analogs are transformed into deoxynucleotide triphosphates and are incorporated into the DNA sequence replacing the cytosine in the process of replication, inhibiting the DNMTs and targeting them for degradation.
How do DNA analogs act to inhibit replication of an RNA virus quizlet?
when incorporated into a virus DNA or RNA during viral replication, nucleoside analog acts to prevent production of new virus. nucleoside analogs take place of natural nucleosides, blocking completion of a viral DNA chain during infection. reverse transcription is halted and virus can’t replicate.
What are structural analogs of nucleotides explain using an example?
Nucleotide analogs are nucleotides which contain a nucleic acid analogue, a sugar, and a phosphate groups with one to three phosphates. Examples include ddhCTP (3ʹ-deoxy-3′,4ʹdidehydro-CTP) produced by the human antiviral protein viperin and sinefungin (a S-Adenosyl methionine analogue) procduced by some Streptomyces.
What are structural analogs of nucleotides?
Structurally, nucleotide analogs are acyclic nucleoside phosphonates (nucleoside monophosphates) that are designed to circumvent the first phosphorylation step necessary for the activation of nucleoside analogs, such as zidovudine, stavudine, didanosine, lamivudine, and abacavir (1.
How is HPV able to keep its genome so small quizlet?
How is HPV able to keep its genome so small? The DNA genome of HPV can only be replicated in the nucleus where host DNA polymerase is found.
When a viral nucleocapsid enters a host cell the capsid must be removed in a process known as?
Penetration or Viral Entry Many unenveloped (or naked) viruses inject their nucleic acid into the host cell, leaving an empty capsid on the outside. This process is termed penetration and is common with bacteriophage, the viruses that infect bacteria.
What do nucleotide analogues do?
Nucleotide analogues represent a major class of anti-cancer and anti-viral drugs, and provide an extremely powerful tool for dissecting the mechanisms of DNA and RNA polymerases.
What step of the influenza life cycle is inhibited by Tamiflu?
Tamiflu binds to the neuraminidase on the surface of the virus particles and hence inhibits the new viral particles’ chemical ability to escape from the infected cell. Hence the influenza virus is restricted to a smaller number of cells and the body’s immune system has a better chance of killing the virus.
How does HPV replicate?
HPV infects dividing basal epithelial cells where its dsDNA episomal genome enters the nuclei. Upon basal cell division, an infected daughter cell begins the process of keratinocyte differentiation that triggers a tightly orchestrated pattern of viral gene expression to accomplish a productive infection.