HIV Chemotherapy

Question 1

What is the importance of reverse transcriptase?

Answer 1

Found in HIV
Does NOT have proof reading function = massive mutation rate = drug-resistant strains

Question 2

What is integrase enzyme?

Answer 2

Insertion of viral DNA into host DNA = permanent infection

Question 3

What is protease enzyme?

Answer 3

Generating functional proteins for viral replication = proteolytic cleavage

Question 4

What are nucleotides made up of?

Answer 4

Nitrogen heterocyclic base
Pentose sugar
Phosphate residue

Question 5

What are nucleotides?

Answer 5

Phosphate esters of nucleosides

Question 6

What are nucleotides components of?

Answer 6

Both RNA + DNA

Question 7

What are nucleosides structure?

Answer 7

Purine/pyrimidine base joined to pentose sugar

Question 8

What are the major purines?

Answer 8

Adenine (A)
Guanine (G)
In DNA + RNA

Question 9

What are the major pyrimidines?

Answer 9

Cytosine (C)
Thymine (T)
Uracil (U) - ONLY IN RNA

Question 10

What do bases exist in?

Answer 10

Specific tautomeric forms = preferred forms
H-bonding super important for helix structure

Question 11

Which base does NOT exhibit tautomerism?

Answer 11

Adenine

Question 12

What is the sugar in RNA?

Answer 12

D-ribose
= chiral = polar

Question 13

What is the sugar in DNA?

Answer 13

2’-deoxy-D-ribose

Question 14

What is the D configuration of the sugar?

Answer 14

4-OH points up

Question 15

What is the L configuration of the sugar?

Answer 15

4-OH points down

Question 16

What is the beta anomeric centre configuration of the sugar?

Answer 16

C1 X points up

Question 17

What is the alpha anomeric centre configuration of the sugar?

Answer 17

C1 X points down

Question 18

What does “SIDES” at end of the word mean?

Answer 18

NO PHOSPHATES

Question 19

When there is NO OH what does it mean?

Answer 19

Difference in chemical stability between DNA + RNA

Question 20

What are triphosphate esters for?

Answer 20

Building blocks of DNA + RNA
= change phosphorylation = change shape = change structure

Question 21

What is phosphorylation under control of?

Answer 21

Kinases

Question 22

What does HIV NOT do?

Answer 22

Encode a nucleoside kinase = relies on host’s own kinases

Question 23

What is the primary structure of DNA?

Answer 23

Primer strand
Template strand
Base = no. of H-bonding

Question 24

What can be considered potential antiviral compounds?

Answer 24

Nucleoside analogues of natural substrates
BUT needs to be recognised by enzymes

Question 25

What bit is important of the nucleotide?

Answer 25

Important for molecular recognition Triphosphate ester Heterocyclic base

Question 26

What is the importance of the triphosphate ester?

Answer 26

Charged + electrostatically bound to metal ions within enzyme structure

Question 27

What is the importance of the heterocyclic base?

Answer 27

H-bonded to complementary base on DNA template = preferred tautomeric form

Question 28

What is the importance of the base component?

Answer 28

Specific H-bonds between bases = maintain fidelity of replication of genetic material = RECOGITION

Question 29

Which base analogue can be a problem?

Answer 29

Adenine analogues = readily metabolised by adenosine deaminase to inosine derivatives

Question 30

What is the MOST important in analogues?

Answer 30

Sugar variations

Question 31

Where can we make analogues for sugars?

Answer 31

Furanose positions 2' + 3' = removal/substitution = STOPS polymerisation BUT does NOT change orientation of base + triphosphate